IlliiBiiilifilllll1 3 0263 00262008 4 y 'Iff / .. / / Biological Field Station BUllETin State University of New York College of Arts and Science at OSV\lEGO RICE CREEK I Ref QII lOS 7 .S vol. 1 no. 1 c.2
I 3 0263 00262008 4 t)' -I f / ':...1 CREEK BIOLOGICAL FIELD STATION 'Jol, 'f: ') 1 BULLETIN // Vol.1 Noo1 Spring 1974 I. Lt h" '. ._2'. ( EDITOR Robert I. Shearer Rice Creek Biological Field Station State University College Oswego, New York 13126 323420
1 January, 1974 PREFACE This inaugural issue of the Rice Creek Biological Field Station Bulletin is the first of a series of Bulletins to be produced with the aim of disseminating information developed by the students and staff of Rice Creek Biological Field Station. It is our intention to prepare the Bulletin as information becomes available with an initial goal of two issues a year. Each issue will contain the results of research on one community until the backlog of data developed since 1967 is exhausted. The type of project that produced the data in individual papers will be indicated so that the reader will be able to judge the merit of each research project. Some problems were developed by staff or as a Master's degree research thesis, others were independent studies and class projects by undergraduates and graduates. Some rearrangement of data and narrative has been made to clarify the meaning for Bulletin readers, but in no case has the meaning been changed. The editorial tasks have fallen on Robert Shearer, the Rice Creek Biological Field Station Technical Specialist. Comments on any phase of the Bulletin are solicited and separates of articles are available upon request. George R. Maxwell, II Director, Rice Creek Biological Field Station State University College Oswego, New York
2 TABLE OF CONTENTS Preface -G. R. Maxwell 1 Introduction-R.I.Shearer 3 Limnological Data Collected From Little Sodus Bay 4 A Chemical and Physical Comparison of Little Sodus Bay, Port Bay, Sodus Bay, and Irondequoit Bay -J. E. Kundell 7 The Distribution of Microcrustaceans at the Mud-Water Interface of LittleSodus Bay -R.A.Spafford 32 Phosphate and Nitrate Study of Little Sodus Bay During Winter Ice Cover and Early Spring, 1972 -K. Del Prete 45 Chlorophyll and Phaeophytin Determination of a Phytoplankton Community During and After Ice Cover -N. D. Tritman 52 An Investigation of the Vertical Distribution of the Meiobenthos ofLittle Sodus Bay -R. I. Shearer 59 Seasonal and Vertical Distribution of Zooplankton in Little Sodus Bay -J. G.Bocsor 66 General Notes A Simple and Efficient Benthos Sorting Dish -R. I. Shearer 75 A Modified K. B. Type Corer -J. E. Demers 76
__3 _-" INTRODUCTION This issue contains selected papers from limnological investigations of Little Sodus and neighboring bays along the southern shore of Lake Ontario. Located approximately 15 miles from the Oswego campus, this sheltered bay has provided our classes with one of several excellent study sites at which they can become familiar with procedures in the field of limnology. The first article of this bulletin is a summary of chemical and biological data from Little Sodus Bay collected by previous limnology classes. It is an attempt to arrange the students' classwork into a meaningful form so that their efforts may be appreciated by others. Some of the data may be questionable and such instances are noted. This is to be expected when introducing students to the many different techniques and equipment used throughout the course. Generally the accuracy of these data are excellent and provides one with a "limnological preview" of Little Sodus before reading papers which follow. The more specific papers represent individual efforts as independent studies or partial requirements for advanced studies. Kundell's and Spafford's papers were submitted as a partial fulfillment for the Master of Science Degree in Education under the advisement of R. A. Engel. The remaining papers were completed as a partial requirement for "Problems in Advanced Limnology" which was taught in Spring of 1972 by R. A. Engel. Much of the collection was conducted through the ice and allows us to have a more complete picture of the limnology of Little Sodus Bay. Robert I. Shearer Technical Specialist Rice Creek Biological Field Station State University College Oswego, New York _._....
4 FIGURE 1 Little Sodus Bay /0 /6 /3 9 (... I
5 D.O. pH Total Alkalinity Total Hardness CalciUm Hardness Magnesium Hardness Chlorides Sulfates Silica Iron (Ferric, Ferrous) Specific Conductance Particulates Dissolved Solids: Total Organic Inorganic Methods Used for Chemical Data (See Fold-Out) Winkler Method Sodium azide modification. Phenolphthalein indicator .0227N NaOH titrant expressed as ppm free CO2 Beckman Electromate. Bromcresol green -methyl red indicator. ManVer Indicator Hach Kit expressed as ppm Calcium carbonate. CalVer II Indicator Hach Kit expressed as ppm Calcium carbonate. Total Hardness minus calcium hardness in ppm. Mercuric nitrate method. Diphenylcarbazone Indicator Buffer. Turbidimetric method using SulfaVer III Hach Kit. Heteropoly Blue Method Hach Kit. 1,lO.Phenanthroline Method Hach Kit. YSI Model 31 Conductivity Bridge -expressed in. micromhos/cm. Corrected to 25C. Millipore filter .45 membrane filter used. Particulates expressed in mg/L or ppm. Millipore filtered water evaporated from preweighed Vyco.r dish. .Residue expressed as ppm. Weight loss of total dissolved solids on ignition expressed in ppm. Weight of dissolved solids after ignition expressed in ppm.
Chemical Data Collected by Limnology Classesa at Littl (All values expressed in PPM unless othen methods used L_ Date & Station 1-15-69 Station #3 (Middle) 1-15-69 Station #4 (South) 1-23-10 Station #4 (South) 1-23 10 Station #1 (North) 1-19-11 Station Lake** 1-19-11 Station #1 (North) 1-19-11 Station #3 (Middle) 1-19-11 Station #4 (South) 9-30-11 Station #4 (South) 9-30-11 Station #3 (Middle) 10-14-11*** Station #4 (South) 10_14_1pttttt Station #4 (South) 10-14-11...... Station #4 (South) 9-14-12 Station #2 9-14-72 Station #3 (Middle) 9-13-13 Station #3 (Middle) 9-13-13 Station #4 (So11th) D.O. % Sat. CO2 pH Total Alk. Total Hard. Calc. Hard. Mg. Hard. Chlorides Sulfa S+ B+ 9.8 .3 1l0% 5% 0.0 8.8 1.5 99.0 101.5 130.0 130.0 100.0 100.0 30.0 30.0 35.0 30.0 N/D 21.0 S B 8.6 9.2 100% 140% 2.0 2.0 8.6 8.55 98.0 99.0 130.0 130.0 1l0.0 1l0.0 20.0 20.0 30.0 35.0 N/D S B 9.3 6.4 105% 10% N/D 8.3 1.8 N/D N/D N/D N/D 28.0 N/D S B 10.2 .2 1l0% <3% N/D 8.5 1.6 N/D 140.1 120.4 19.1 41.0 N/D S B 9.1 9.1 105% 13% 0.0 0.0 8.6 8.5 91.5 92.0 134.0 102.0 32.0 20.5 18.0 S B 9.5 1.2 105% 12% 0.0 6.5 8.1 8.1 95.5 115.0 131.0 118.0 19.0 20.5 20.0 S B 9.8 9.9 108% 91% 0.0 0.5 8.1 8.3 99.5 98.5 136.0 102.0 34.0 25.0 11.0 S B 9.8 8.4 108% 93% 0.0 0.0 8.6 8.5 102.5 100.5 132.0 108.0 24.0 24.0 18.0 18.0 S B 1.1 10. N/D 0.0 0.0 8.5 8.6 N/D 106.0 150.0 134.0 126.0 16.0 10.0 21.0 29.5 24.0 N/D S B 8.2 9. N/D 0.0 0.0 8.63 8.5 109.0 98.0 p-34.0 138.0* 124.0* N/D 26.5 28.5 24.0 N/D S B 14.5 N/D 140+% N/D 0.0 N/D 9.0 N/D 19.0 98.0 40.0 29.0 N/D S B 1l.0 N/D 110% N/D 0.0 N/D 8.9 N/D 91.0 100.0 20.0 29.0 30.0 S B 15.1 N/D 140+% N/D 0.0 N/D 9.3 N/D 81.0 30.0 120.0 10.0 28.0 N/I S B 6.6 1.4 15% 80% 0.0 5.0 8.15 8.05 91.0 90.0 126.0 ...26.0 124.0 N/D 2.0 N/D 26.0 26.0 N/r S B 8.1 5.6 90% 80% 0.0 2.25 8.5 9.3 42.5 42.5 28.0 tI.26.0 122.0 102.0 6.0 24.0 27.0 29.0 N/r S B 9.4 1.1 103% 15% 0.0 2.0 8.35 8.1 85.5 90.5 il30.0 100.0 30.0 11. 5* N/I S B 9.1 9.8 106% 110% 0.0 0.0 -8.5 8.5 91.0 90.0 40.0 116.0 24.0 30.4 N/I Value questionable 205, Limnology, taught at S.U.C.0. by R. A. Engel. ** Lake Station (Not +S = Surface Sample; B = Bottom Sample. *** Station #4 (South)++ Specific Conductance in micromhos/cm. corrected to 25 C. used over the yearN/D represents No Data. were in close
"oj 30dus Bay, = noted. 3.ge. ) ++ TotalTotal Spec. Partic-Dis. Dis.Dis. Silica ulatesIron Condo Organic Inorganic .03 Solids 313N/D N/D N/D N/D N/D.03 .04 N/D N/D N/D N/D N/D N/D.06 N/D 310 N/D N/D N/D5.21.5 4.8N/D 301 N/D N/D N/D3.35 0.0 1.4 210.0 94.0 116.0.9 307 122.0 74.0 .0.0 2.61.1 310 196.0 0.0 281 120.05.6 196.0 76.01.05 4.6 124.0 48.00.01.1 310 172.0 1.2 0.0 310 50* N/DN/D N/D0.0N/D 315 0.0 3081.1 21.6* N/D N/D N/DN/D 0.0 318 N/D N/D0.0 1.8 HID313.53 I N/D N/D.48 0.0 1.1 HID313 .40 0.0 N/D N/D HID309 .71 J 224 .141.95 N/D N/D N/D HID223 .761.9512.6219.9 N/D N/D N/D N/Di 218 49.4*1.2 N/D N/D N/D2.1 280.5 3.6N/D "1 N/D N/D N/D1.4 N/D HID233.7 )wn on Figure 1) was north of Little Sodus Bay. Depth 21 M. 1 Figure 1 is an approximate location of the south station sampling. In the case of 10-14-71, the 3 areas sampled ty to the marking on Figure 1. I
7 A Chemical and Comparison of Little Sodus Bay, Port Bay, Sodus Bay, and Irondequoit Bay. James Edward Kundell* INTRODUCTION Approximately thirteen and one half percent of the population of the United States and thirty three percent of the population of Canada inhabit the Great Lakes basin. This area comprises only three and one half percent of the land in the United States (Powers and Robertson, 1966). It is believed that this area may become the fastest growing section of the United States due to its apparent inexhaustible supply of water (Powers and Robertson, 1966). The eutrophication of these lakes, however, may make them unfit as a source of water. Thus, all information pertaining to the pollution and/or eutrophication of these lakes is of importance. In the summer of 1970, a study of four bays along the southern edge of Lake Ontario was undertaken. Port Bay and Little Sodus Bay were studied on 20 August and Sodus Bay and Irondequoit Bay on 21 August. This study was a chemical and physical comparison of the four bays. Biological samples were taken and preserved for identification and enumeration at a future date. DESCRIPTION OF BAYS The four bays studied are located along a fifty mile portion of the southern edge of Lake Ontario (see Figure 1). All of the bays are similar in their geologic formation in that their basins were gouged out, as were the Great Lakes, by the advancing glaciers during the last ice age (Powers and Robertson, 1966). The water level in these bays is now about 75 meters (250 feet) above sea level (Forest, 1968). Due to their proximity to each other, all the bays are exposed to approximately the same major environmental conditions (seasons, temperature variations, precipitation). Characteristics unique to each bay are discussed below. Location of stations are marked on the maps of each bay (see Figures 2, 3, 4, and 5). Little Sodus Bay Little Sodus Bay is the eastern most of the four bays studied (see Figure 2). It is located near the village of Fair Haven, New York, in Cayuga County (Fair Haven Quadrangle: 76' West, 43' North). *Submitted as partial fulfillment for the Master of Science Degree in Education under the advisement of R. A. Engel. I
():) Approximate Scale: 0 5 10 15 20 25 30 35 Miles , , t LAKE ERIE CANADA FIGURE I -GENERAL MAP OF AREA LAKE ONTARIO GENESEE RIVER 3 ST. LAWRENCE RIVER ONEIDA LAKE FINGER LAKES
9 Little Sodus Bay is the second smallest of the four bays studied. It has a surface area of 292 hectares There is one small stream entering Little Sodus Bayo at its southern end. Others may provide water only during periods of rapid water runoff. Therefore, most of the water in the bay enters from Lake Ontario. The village of Fair Haven is located on the south eastern shore of Little Sodus Bay and there are camps along most of the shorelineThe surrounding areao consists mainly of farmland with orchards being prevalent o Port Bay Port Bay (see Figure 3) is located west of North Wolcott, New York, in Wayne County (North Wolcott Quadrangle: 76' West, 43' North). Port Bay is the smallest of the four bays studied with a surface area of 7.6 hectares. This bay has two tributaries, Wolcott Creek and Beaver Creek entering ito There are no villages located near the shores of Port Bay. Camps are located along the eastern and western shores. The southern edge is relatively free of camps due to the marshes (see Figure 3). The surrounding area is rural with much of the land cleared for agriculture. Sodus Bay Sodus Bay (see Figure 4) lies between the villages of Wolcott, New York, and Sodus, New York, in Wayne County (Sodus Point Quadrangle and Rose Quadrangle: 76' West, 43' North). Sodus Bay is the largest of the four bays studied with a surface area of 1327 hectares. Sodus Bay is fed by several tributaries. There are no large population centers located on the shores of Sodus Bay. However, camps are located in various areas along the eastern and western shores of the bay. The northern portion of the bay is relatively free of inhabitants as is the southern portion. The bay south of Route 104 is marshy and set aside as a wildlife sanctuary (see Figure 4)0 The area surrounding Sodus Bay is rural with agriculture, primarily apple orchards, being predominant. Irondequoit Bay Irondequoit Bay (see Figure 5) is located east of the city of Rochester, New York, in Monroe County (Rochester East Quadrangle: 77' West, 43' North). Irondequoit Bay is the second largest of the four bays with a surface area of 652 hectares. It is fed by Irondequoit Creek and several other streams. The water very seldom if ever, mixes with the water of Lake Ontario (Tressler, et al., 1953). The area around Irondequoit Bay is heavily populated by over 100,000 people (Wilson, et 1969)0 The city of Rochester, New York, is located on the western shore and the remaining area is mainly residential.
10 FIGURE 2 L1ttle Sodus Bay ......./8---' 14 13 10 9 II< 13 10_ :Y.
I 11 FIGURE 3 Port Bay /,'l. _'2 6
r 12 FIGURE 4 Sodus Bay
13 FIGURE 5 Irondequoit Bll 1 Kilometer Interval 10 Feet )'.' ,\1.1.
14 METHODS AND MATERIALS Physical Studies All water samples were obtained using a two liter Kemmerer water bottle. Air and water temperatures were obtained using the Whitney Thermometer, Model TC-5A. Wind direction and speed were read with a hand held cup-anemometer. Wind speed is reported in knots. Per cent cloud cover was estimated. Light penetration readings were obtained by using the G. M. Submarine Photome1 Model 268wA310. Results are reported in microamps (conversion to foot candles = microamps X 0.25). Turbidity results were obtained with the Bausch and Lomb Spectronic 20 using one inch test tubes at 450 millimicrons. Secchi disk depths were determined using a black-white quadrant, ten inch diameter secchi disk. Specific conductivity at 25C was obtained with the YSI conductivity bridge with commercial probe 1.0 K. The results are reported in micromhos per centimeter, Particulate concentrations were obtained by heating a millipore filter at 103C for 15 minutes, letting it cool and weighing it. Then, a 500 rnl composite water sample was filtered. The filter was removed, heated at 103C for 15 minutes and reweighed. The difference in weight multiplied by two provides the particulatE l concentration in parts per million. itChemical Studies All water samples were obtained using a two liter. Kemmerer water bottle. The Beckman-Electromate pH meter, Model 1009, standardized at 8.6 pH was used to determine the pH levels. Carbon dioxide levels were obtained by titrating a 25 ml water sample containing phenopthalein with 0.0227N sodium hydroxide The number of milliliters of sodium hydroxide necessary to turn the0 solution pink mUltiplied by 40 is the carbon dioxide level in parts per million. Alkalinity was determined by titrating a 50 ml water sample containing Brom cresol green, methyl red indicators with 0.02N hydrochloric acid. The number of5o milliliters of titrant used multiplied by twenty gives the alkalinity in parts per million. Total hardness was determined by titrating a 50 ml water sample containing "Hach's Man-Vern indicator with a modified EDTA titrant. The milliliters of titra multiplied by twenty provides the total hardness in parts per million as calcium carbonate. Silica concentrations were obtained with a 25 ml water sample using the Heteropoly Blue Method and colorimeter readings on the Hach Colorimeter Model DR 4530B. I
15 Chloride concentrations were determined by using the Mohr Method of titrating a 100 ml sample with standard silver nitrate solution. The milliliters of titrant to change the color from yellow to red multiplied by five gives the chloride concentrations in parts per million. The amount of iron contained in the water samples was determined by using the 1,10-phenanthroline Total phosphate concentrations after acid hydrolysis were obtained by using the stannous chloride method and reading on the Bausch and Lomb Spectronic 20 at 620 millimicrons (Rainwater and Thatcher, 1960). The Azide Modification of the Winkler Method was used to determine the dissolved oxygen (DO) content of the water. A 200 milliliter sample was titrated with 0.025N sodium thiosulfate. The results are reported in parts per million. DISCUSSION OF THE OBSERVATIONS AND RESULTS Physical Characteristics Of all the factors that may affect water and, in turn, be affected by water, light is one of the most important. Since all the bays studied are located between 43' and 43 '. North of the equator, the incidence and quality of the light reaching them ,should be quite similar. By comparing the deck light readings and the surface light readings (see Tables 1, 2, 3, and 4) it is possible to determine approximately what per cent of the available light is reflected. The results of this are listed below. Percent Reflected Light Little Sodus o 1207 o o o Port o 8.7 Sodus 0 12. 70000 000000 These are the mean values for the three stations in each bayo Reid (1961) states that the amount of light reflected from a body of water may vary from 5% to 35% of the total available radiation. The variations obtained are due to the time differences which would produce different angles of incidence and the surface conditions of the water. Once the light has entered the water, it may be absorbed or transmitted. According to Birge and Juday (1929-32), only 47% of the total radiation penetrates to the depth of one meter in distilled water. The other 53% of the radiation is transformed into heat (Reid, 1961). Of the lakes studied by Birge and Juday, the amount of radiation penetrating to the depth of one meter varied from 5% to 40% of the total available radiation (Birge and Juday, 1929-32).
TABLE 116 TEMPERATURE AND LIGHT DETERMINATIONS Little Sodus Bay August 20, 1970 St. #1 St.#2 St. #3 DEPTH TEMP.* LIGHTo PERCENT x TEMP.* LIGHTo PERCENT x TEMP. LIGHTo PERCEI !i l-. 'f :f j ; I I I ! Deck 27.3 3200 4000 Surf. 23.8 2400 100 24.0 3800 1/2 01 23.8 1700 70.8 24.0 2600 1 OJ 23.8 850 35.4 23.9 1600 2 01 23.7 300 12.5 23.9 500 3 01 23.7 90 3.8 23.6 1954 01 23.65 40 1.7 23.5 95 5 01 23.6 15.5 0.6 22.5 45 6 01 23.6 8.5 0.4 21.8 15 7 01 22.7 2.5 0.1 20.9 4.5 8 01 19.8 1.5 0.06 19.1 2.7 9 01 18.4 1.0 0.04 18.0 1.5 10 01 17.5 0.75 0.03 10.7501 16.9 0.50 0.02 *Temperature measured in degrees centigrade Light measured in microamps xPercents are calculated on the surface light readings TABLE 2 100 68.4 42.1 13.2 5.1 2.5 1.2 0.4 0.1 0.07 0.04 24.0 23.95 23.9 23.7 23.6 23.0 22.8 2400 2200 1800 750 300 95 50 30 100 81.8 34.1 13.6 4.3 2.3 1.4 TEMPERATURE AND LIGHT DETERMINATIONS Port Bay Augus t 20, 1970 St. #1 St.#2 St.#3 DEPTH TEMP.* LIGHTo PERCENT x TEMP.* LIGHTo PERCENT x TEMP.* LIGHTo PERCn, Deck Surf. 1/2 01 1 01 2 01 3 01 4 01 5 01 6 01 6.4 01 34.0 24.1 23.9 23.55 23.45 23.4 23.25 3680 3600 1640 360 36 5 1 100 45.6 10.0 1.0 0.1 0.02 24.1 23.65 23.55 23.50 23.4 23.4 23.4 3600 2720 1600 250 45 1.4 1.5 0.4 100 58.8 9.2 1.7 0.05 0.05 0.01 24.4 24.3 24.1 23.8 23.65 23.5 22.7 21. 9 21.75 3040 3040 1280 350 50 9.3 2.3 0.5 0.25 0.20 100 42.1 11. : lot 0.: 0.( 0.( 0.1 0.1 *Temperature measured in degrees centigrade Light measured in microamps xPercents are calculated on the surface light readings
TABLE 3 TEMPERATURE AND Sodus Bay lIGHT DETERMINATIONS Augus t 21, 1970 17 St. #1 St.#2 St.#3 DEPTH TEMP.* LIGHTo PERCENT x TEMP.* lIGHTo PERCENT x TEMP.* lIGHTo Deck Surf 1/2 m 1 m 2 m 3 m 4 m 5 m 6 m 7 m 8 m 9 m 10m 11 m 11 .3m 22.2 23.5 23.4 23.4 23.4 23.4 23.4 23.3 23.2 23.2 23.2 23.2 23.2 19.1 18.3 4480 3760 2720 1480 580 215 105 45 20 5.5 4.3 2.0 1 .0 0.,5 0.4 100 72.3 39.4 15.4 5.7 2.8 1 .2 0.5 0.1 0.1 0.05 0.02 0.01 0.01 23.55 23.5 23.5 23.5 23.5 23.4 23.4 23.35 23.3 23.2 23.1 4400 3840 2560 1520 460 142 64 22.3 11 .2 4.9 2.2 0.75 100 66.7 39.6 12.0 3.7 1 .7 0.6 0.3 0.1 0.05 0.01 24.3 24.3 24.1 23.6 23.3 3680 3440 2000 1360 40 6.5 100 58.1 39. 1. o. *Temperature measured in degrees centigrade light measured in microamps xPercents are calculated on the surface light readings TEMPERATURE TABLE 4 AND lIGHT DETERMINATIONS St. #1 I rondequoi t Bay August 21, St.#2 1970 St.#3 DEPTH TEMP.* LIGHT? PERCENT x TEMP.* lIGHTo PERCENTx .* lIGHTo PERCENT Deck Surf 1/2 m 1 m 2 m 3 m 4 m 5 m 6 m 7 m 8 m 9 m 10m 11 m 12 m 13 m 14 m 15 m 16 m 17 m 18 m 19 m 20 m 21 m 22 m 23 m 20.5 23.7 23.7 23.7 23.7 23.7 23.7 23.7 23.7 23.7 4800 3200 2400 1000 160 40 10 2.5 0.5 0.0 100 75.0 31 .3 5.0 1 .3 0.3 0.08 0.02 0.00 23.8 23,.8 23.8 23.8 23.8 23.8 23.8 23.8 23.8 23.8 23.8 5600 4160 2400 820 190 40 11 .5 3.2 1.a 0.4 0.1 0.0 100 57.7 19.7 4.6 1 .0 0.3 0.08 0.02 0.01 0.002 0.0 24.2 24.2 24.2 24.15 24.15 23.05 23.25 21 .0 19.6 18.9 15.4 13.9 11 .5 10.5 10.0 9.4 8.9 8.6 8.2 7.8 7.6 7.3 7.2 6.9 6.9 4160 3600 2200 1200 320 77 32 10.6 4.0 1 .75 1 .0 0.5 0.1 0 0 0 0 0 0 0 0 0 0 0 0 0 100 61 1 33.3 8.9 2.1 0.9 0.3 0.1 0.05 0.03 0.01 0.00 0 0 0 0 0 0 0 0 0 0 0 0 0 *Temperature measured in degrees centigrade alight measured in microamps xPercents are based on the surface light readings
18 Below are listed the percents of total surface radiation measured at one meter in each of the bays, determined from values presented in Tables 1, 2, 3, and 4. These values are the means for the three stations in each bay. Bay Percent Radiation at 1 meter Little Sodus 37.2 Port o 10.2 Sodus 0 395 Irondequoit 28.1 These values indicate that the water in Little Sodus Bay and Sodus Bay were relatively transparent while the water in Port Bay was not (see Figures 6, 7, 8, and 9). These observations are substantiated by the secchi disk readings for the bays (see Tables 5 and 6). Irondequoit Bay was intermediate in this respect. The euphotic zone is the area of water in which photosynthesis may occur. The lower limit of this zone is the compensation level and is defined as the depth at which organic respiration and decomposition use oxygen at a rate equal to that at which it is produced in a 24 hour period (Reid, 1961). Schomer (1934) found that the compensation level was inversely related to the dissolved color and ranged at depths from 1 to 15 meters. Schomer and Juday (1935) determined the compensation level in several lakes to be the depth at which about one percent of the surface radiation was present. Based on this, the compensation levels for the four bays are as follows. Compensation Level Little Sodus o o 5.0 meters Port oo o o .2.1 meters Sodus o o 4.1 meters Irondequoit 3.5 meters These values were calculated from the means for the three stations in each bay (see Tables 1, 2, 3, and 4). At the three stations where there was a definite thermocline, St. #1 and St. #2 in Little Sodus Bay, and St. #3 in Irondequoit Bay (see Figures 6 and 9), it is located just below the estimated compensation levelo It is also indicated by the graphs that the euphotic zone closely corresponds to the epilimniono According to Reid (1961), this is what might be expected of most temperate lakes during summer thermal stratification. Turbidity values (see Tables 5 and 6) correlate closely with the data already discussed. Port Bay and Irondequoit Bay had the highest turbidity readings while Little Sodus Bay and Sodus Bay had much lower readings. Since turbidity refers to the "opaqueness" produced in water by suspended material (Reid, 1961), it is understandable that particulate concentrations should correlate with the turbidity values Little Sodus Bay and Sodus Bay were low in particulates while Port Bay and Irondequoit Bay were much higher (see Tables 5 and 6). The data indicates that a greater percentage of the particulates in Irondequoit Bay, as opposed to Port Bay, were larger than 0.45 u. This may be due to the deposition of sediment from the Irondequoit Bay watershed (Forest, 1968). Tressler (1953) related a decrease in transparency during April and May to the allochthonus detritus from the erosion of the steep banks.
19 Figure 6 Figure 1 Percent of Surface Radiation Percent of Surface Radiation o 20 40 60 80. 100 o 20 40 60 80 100 1 1 2 2Light Penetration Light Penetration St. #1, St. #2, and St. #3 St. #1, St. #2, and St. #3 Little Sodus Bay Port Bay3 3...--. August 20, 1970 August 20, 1970 .p 4 .p 4 p.. p.. Q) Q) i=l i=l 5 5 6 6 1 1 Figure 8 Figure 9 Percent of Surface Radiation Percent of Surface Radiation o 20 40 60 80100 o 20 40 60 80100 1 1 2 2 Light Penetration Light Penetration St. #1, St. #2, and St. #3 St. #1, St. #2, and St. #3 ...--. ...--. 3 Sodus Bay 3 Irondequoit Bay August 21, 1970 August 21, 1910 .p p.. Q) 4 .p p.. Q) 4 i=l i=l 5 5 6 6 7 1
20 TABLE 5 PHYSICAL DATA Little Sodus Bay and Port Bay August 20, 1970 Little Sodus Bay Port Bay DETERMINATION Time Air Temp. Wind Cloud Cover Secchi Dist (cm) Turbidity (JTU) Top Bottom Specific conductivi Ot(Micromhos/cm at 25 ) #1 11:00 am 270 C 8K 75% 30 26 #2 12:00 N SSW 9K 75% 22 36 #3 12: 30 SW 6K 75% 179 30 22 pm #1 3:00 pm 340 C W7K 40% 71 42 #2 4:00 pm W7K 40% 76 44 44 #3 4:3( W71 40% 86 39 42 Top Bottom Pa rti cul a tes* Depth 284 312 lO.75m 281 305 8 ppm 8.7m 284 289 4.3m 290 4m 290 297 13 ppm 5m 310 302 6.4n *A composite sample made from water from all stations in each bay was tested. TABLE 6 PHYSICAL DATA Sodus Bay and Irondequoit Bay August 21, 1970 Sodus Bay I rondequo it Bay DETERMINATION #1 #2 #3 #1 #2 Time 4:00 pm 4:30 pm 5:00 pm 10:45 am 11 :45 am 1 Air Temp. 22.20C 20.50C Wind NW 11K NW 10K NW 10K NW 11K NW 11K Nl 25% 25% 2!Cloud Cover 10% 10% 10% 102 1Secchi Dist (cm) 186 170 192 80 ( Turbidity (JTU) Top 26 22 1642 42 42Bottom 30 22 16 36 Specific Conductivity (Micromhos/cm at 250C) 879 ETop 285 284 275 728 885 1Bottom 285 282 278 888 Particu1ates* 7.6 ppm 16 ppm Depth 11.3m 8.5m 2.6m 6.8m 8.7m A composite sample made from water from all stations in each bay was tested.
21 Specific conductivity refers to the total amount of ionized material in water (Reid, 1961)0 A mean specific conductivity value for each bay is listed below. Mean Specific Conductivity (micromhos/cm at 25C) Little Sodus 292.5 Port o o .297.8 Sodus o o 281.5 Irondequoit o 9l1.7 Irondequoit Bay differs drastically in specific conductivity from the other bays. Tressler (1953) states that the mean surface specific conductivity in Irondequoit was 563 units (unspecified) in 1939. The mean surface specific conductivity in Irondequoit Bay was 829 micrornhos/cm at 25C (see Table 6). If these units are comparable, then there has been a large increase in specific conductivity since Tressler did his stuqy. Since, geologically, the Irondequoit Bay watershed does not differ from the other three bays and since there appears to have been a dramatic change in the mean conductivity in this bay, the ionized material must have been produced' by the only major difference between the bays--population. The city ot: Rochester, New York, is located on the shores of Irondequoit Bay (see Figure 5) while the other three bays are relatively free of population centers (see Figures 2, 3, and 4). According to Bubeck (1970) the city of Rochester has dumped industrial, storm sewage, and agricultural waste in the bay which have resulted in this high concentration of organic and inorganic material. The specific conductivity values obtained for Little Sodus Bay, 'Port Bay, and Sodus Bay were relatively low compared to the values presented by Berg (1963). He reports the specific conductivity of Lake Erie to be 318 micromhos/cm and for Lake Ontario off Nine Mile Point to be 306 micromhos/cmo West of the city of Rochester is Braddock Bay (see FigUre 1)0 Berg (1963) reports the specific conductivity of this bay to be 459 micromhos/cm. This bay, like Irondequoit Bay, is near a population center, Brockport, New York, and receives pollutants from it (Wilson, et al., 1969). Chemical Characteristics Oxygen content of the .water is dependent upon a number of factors. The release of oxygen by plankton and rooted aquatic plants in the euphotic zone and absorption of oxygen from the atmosphere tend to increase its concentration in the epi1imnion (Reid, 1961). Below the compensation level lies the aphotic zone in which there is insufficient light for photosynthesis to occur. Oxygen deficiencies may exist in this region even though the cooler temperature of the water would allow a much higher concentration of oxygen (Theroux, 1943). Oxidation of organic material occurring here depletes the amount of oxygen (Welch, 1952). Thus it is possibleto have a clinograde DO curve formed (Reid, 1961). A clinograde DO curve was present at St. #1 in Little Sodus Bay, St. #1 in Sodus Bay, and St. #3 in Irondequoit Bay (see Figures 10, 12, and 13). This was made possible by the greater depth available at these three stations; all other stations being too shallow for the formation of a clinograde DO curve and/or distinct thermocline. It should be pointed out that
22 at these three stations, the start of clinograde DO curve, thermocline, and compensation level were all located at nearly the same depth. It is apparent in comparing this stuqy of Irondequoit Bay to Tressler's, which was done in 1939, that therehas been little change in the DO conditions during this time (Tressler, et al., 1953). At St. #3, Tressler found no oxygen below ten meters during the month of August, as was the case in this stuQy (see Figure 13). The DO concentrations were within the range obtained by Tressler (see Table 8). The oxygen determinations (see Tables 7 and 8) indicate that Little Sodus Bay, Sodus Bay, and Irondequoit Bay are all eutrophic lakes. This is apparent since each had a thermocline and an oxygen deficient hypolimnion (Ruttner, 1963). Tressler (1953) substantiates this for Irondequoit Bay. St. #3 in Port Bay (see Figure 11) appears to have had a partial thermocline accompanied by a decrease in :00 However, due to the shallowness of the bay, DO was still present at the bottom. This lack of thermocline and/or clinograde DO curve does not mean that Port Bay was not a eutrophic condition. This orthgrade oxygen curve can also be present in a eutrophic lake (Ruttner, 1963). In general, it may be expected that the carbon dioxide content of the water would be opposite that of the oxygen. This is due to their antithetic roles in the photosynthesis-respiration cycle (Reid, 1961). Values obtained for carbon dioxide concentrations in the four bays agree with this prediction (see Tables 9 and 10). The highest carbon dioxide content was obtained at the bottom of St. #3 in Irondequoit Bay (see Table 10). Tressler (1953) relates this high carbon dioxide content to the inflow of "polluted water" from Irondequoit Creek, the high decomposition of organic matter at the bottom, and the lack of circulation of the bay water with that of Lake Ontario. There was no free carbon dioxide present in the surface water from any of the bays nor in the bottom samples from several of the stations (see Tables 9 and 10). This situation was produced by the photosynthetic activity occurring at the ( time the samples were taken. The data for pH, carbon dioxide, hardness, and alkalinity indicate that these are basic, hard water lakes (see Tables 9 and 10). This, in part, is due to the limestone bedrock in the area (Berg, 1963). It is apparent from the data that Irondequoit Bay differed from the other three bays by having much higher alkalinity concentrations (see Tables 9 and 10). Tressler (1953) found the highest mean alkalinity in midsummer to be 150 ppm. The mean alkalinity for Irondequoit Bay determined by this study was 188 ppm (see Table 10). Tressler (1953) relates the high alkalinity to the inflow of Irondequoit Creek. He states that the "polluted water" from this creek flows along the bottom of the bay and is trapped in the deeper parts of the lake. Tressler (1953) also adds that the great amount of decomposition occurring on the bottom also affects the alkalinity. Berg (1963) relates the blooms of blue-green algae and diatoms to the presence \I of silica in water. Reid (1961) states that these organisms may 'remove much of the silica from the water. Tressler (1953) found diatoms to be common during a large
23 FIGURE 10 I?ISSOLVED OXYGEN AND TEMPERATURE CURVES Sodus Bay 20, 1970 St. #1 St. #2 St. #3 D. o. (ppm) D. O. (ppm) D.O. (ppm) o 5 1015 51015 o 51015S.......-.........---.,-.-.-s........---...,....----.,......----5 5 10 1 15 "----'l.....-I-I--o+--t--P--... 15 --t--+-............ 15'--+--O+-.....-........-t--....... o 5 1015 2025 30 35 o 5 101520253035 o510152025 30 35 Temp. (OC) Temp. (OC) Temp. (OC) FIGURE 11 DISSOLVED OXYGEN AND TEMPERATURE CURVES Port Bay August 20, 1970 St. #1 St. #3 D.O. (ppm) D.O. (ppm) S0 5 1015sO 0 5 1015 20 25 3035 o 5 10 15 2025 3035 0 5 1015 20 25 30 35 Temp. (OC) Ter2p. (OC) Temp. (OC) 5 DO Temp. 5 +.:> P; (1) 10 10 15 15 S 0 10 5 10 15
24 FIGURE 12 DISSOLVED OXYGEN: AND TEMPERATURE CURVES Sodus Bay August 21, 1910 S 0 St. #1 D.O. (ppm) 5 10 15 0 S St. #2 D.O. (ppm) 5 10 15 0 S St. #3 D.O. (ppm) 5 10 15 5 DO Temp. 5 DO Temp. 5 DO Temp. 10 10 10 15 15 15 0 5 10 15 20 2530 35 0 5 101520253035 Temp. (DC) Temp. (DC) FIGURE 13 DISSOLVED OXYGEN AND TEMPERATURE CURVES AND Irondequoit Bay August 21, 1970 St. #1 St. #2 D.O. (ppm) D.O. (ppm) o 5 1015 5 1015s0S+----'--""T"""+--.-.. I DO Temp. DO Temp 5 5 5 10 10 10 15 15 15 o 5 10 15 20253035 0 5 1015 20253035 Temp. (DC) Temp. (DC) 20 25 o 5 1015 2025 30 35 Temp. (DC) FIGURE 14 DISSOLVED OXYGEN TEMPERATURE CURVES Irondequoit Bay August 21, 1970 St. #3 D.O. (ppm) 5 10 15 Temp. 0 5 10 152025 30 35 Temp. (DC)
25 (ppm; TABLE 7 DISSOLVED OXYGEN Little Sodus Bay and Port Bay August 20, 1970 Little Sodus Bay Port Bay STATION DEPTH DO (ppm) DEPTH DO #1 Surface 9.6 Surface 8.0 #1 7m 6.9 #1 10.25 m (Bot.) 0.0 4 m (Bot.) 6.3 #2 Surface 8.0 Surface 7.7 #2 7m 0.0 #2 8.5 m 0.0 5 m (Bot.) 5.4 #3 Surface 5.8 Surface 5.6 #3 4.3 m (Bot.) 3.7 6.4 m (Bot.) 1 .2 TABLE 8 DISSOLVED OXYGEN Sodus and Irondequoit Bay August 21, 1970 Sodus Bay I rondequoi t Bay STATION DEPTH DO (ppm) DEPTH DO (ppm) #1 Surface 7. 1 Surface 7.7 #1 8 m 7.1 #1 11 3 m (Bo t. ) 4.1 6.8 m (Bot.) 7.3 #2 Surface 6.2 Surface 8.0 #2 6 m 4.8 6 m 7.4 #2 8.5 m (Bot.) 4.7 8.7 m (Bot.) 6.6 #3 Surface 10.5 Surface 9.2 #3 6 m 2.2 #3 10m 0.0 #3 2.6 m (Bot.) 8.0 23 m (Bot.) 0.0
26 TABLE 9 CHEMICAL DATA Little Sodus Bay and Port Bay August 20, 1970 Littl e Sodus Bay Port Bay DETERMINATION* pH ( Sur) pH (Bot) CO 2 (Sur) CO 2 (Bot) Al kal i nity Ca rbonate (Sur) Bicarbonate (Sur) Ca rbona te (Bot) Bicarbonate (Bot) Hardness Total Calcium Sil i ca Chlorides I ron Phosphate** St. #1 9:.#2 8.7 8.7 7.65 7.5 0 0 8 8 4 4 84 82 0 0 112 104 132 126 96 94 2.6 2.1 18 25 0.02 0.03 +320ppb -20ppb St.#3 8.5 7.9 0 4 4 88 0 92 124 106 1.55 25 0.02 St. #1 St. #2 9.35 9.25 9.2 9.0 0 0 0 0 14 14 94 96 10 10 96 100 136 136 106 104 2.8 3.2 31 30 0.12 0.09 +750ppb -50ppb St. 8.8 7.7 0 4 2 112 0 116 158 106 3.5 30 0.16 i I All chemical determinations except pH and Phosphates reported in parts per million. t !: ** A composite sample was made from water from all stations in each bay. I, TABLE 10I I CHEMICAL DATA Sodus Bay and Irondequoit Bay August 21, 1970I Sodus Bay I rondequoi t Bay DETERMINATION* ST. #1 ST.#2 ST.#3 ST. #1 ST.#2 ST.#3 pH (Sur) 8.6 8.5 8.9 9.0 9.1 9.15 pH (Bot) 8.4 8.4 8.6 9.0 9.0 7.5 CO2 (Sur) 0 00 0 0 0 C02 (Bot) 0 0 0 0 020 Al ka1i nity Carbonate (Sur) 2 1 2 24 24 30 Bicarbonate (Sur) 88 83 74 152 156 150 Ca rbonate (Bot) 1 2 4 22 26 0 Bicarbonate (Bot) 87 86 82 156 154 240 Hardness Total 108 122 114 320 322 326 Calcium 90 94 86 232 240 200 Sil i ca 2.25 2.13 2.30 1.8 1.9 4.3 Chlorides 32 35 31 142 142 180 Iron 0.04 0.04 0.04 0.14 0.11 0.07 Phosphates** 190ppb 50ppb 1100ppb 50ppb All chemical determinations except pH and Phosphates reported in parts per million. ** A composite sample was made from water from all stations in each bay.
27 part of the year and blue-green algae to be most common during August and September in Irondequoit Bay. It is difficult to'determine the effect that the plankton had on the silica concentrations since measurements would have to be made at various times during the year and it has not been ascertained if blue-green algae and/or diatoms were even present when the samples were taken. Ruttner (1963) states that the concentrations of chlorides may be high when salt beds are located in the watershed. Salt strata underlie the entire Finger Lakes region (Berg, 1963)0 Since this region lies just south of the bays and' since the watersheds of these bays originate in this area, it is likely that the chlorides are carried in by inflowing water. Little Sodus Bay has the lowest chloride concentrations and is the only one of the bays without a distinct tributary. In 1910, the chloride content of Lake Erie was 7 ppm but in 1964, it had increased to 23 ppm (Owmbey and Kee, 1967). Arnold (1971) states that the chloride concentrati.on in Lake Erie is now 26 ppm. Dobson (1967) calculated the increase in chloride concentrations in Lake Ontario at 19% per decade. Weiler and Chawla (1969) place the chloride concentrations of Lake Ontario at 27.5 ppm. These values are relatively close to those obtained for Little Sodus Bay, Port Bay, and Sodus Bay (see Tables 9 and 10). However Irondequoit Bay has chloride concentrations five times those found in the other bays (see Table 10). Tressler (1953) did not determine the chloride concentrations for Irondequoit Bay in 1939. Weiler and Chawla (1969) relate the increase in chloride concentrations in Lake Ontario to the activities of humans. Owmbey and Keey (1967) determined the sources of chlorides in Lake Erie to be: Source Percent Upstream Watershedoo27 Municipal Wastewaters 4 and Highway Saltingll o Since the city of Rochester, New York, is located on the shores of Irondequoit Bay, it is that the comparatively high chloride concentrations are due to its effluent. McKee and Wolf (1963) state that the following concentrations of chloride will not normally be deleterious to the specified use: Use Chloride Concentration Domestic Water Supply o.250 ppmo Industrial Water Supply o 50 ppm Irrigation IOO ppmo Stock and Wildlife150 ppm The mean chloride concentration obtained for Irondequoit Bay was 155 ppm (see Table 10). This high chloride content renders this water unfit for industry, crops, and wildlife.
2 28 i b I .I i Iron concentrations in water are usually below 0.2 ppm (Reid, 1961). Thj was true in all four of the bays studied. The mean iron concentration for thE bays were: Mean Concentration of Fe Little Sodus .o.04 ppm Port oo OQOo ppm oOQooooOo02 ppm Irondequoit0.12 ppm Berg (1963) reports the iron content for Lake Ontario off Nine Mile Point to t 0.05 ppm, in Braddock Bay to be 0.43 and in Lake Erie, 0.47 ppm. Thus, t iron concentrations for the bays studied is not a major influence in the eutre cation of these bays. Skoch and Britt (1969) state that Ilof all the nutrients, phosphorus may'" be the initial factor in the development of eutrophic conditions." Phosphorus is necessary for energy transfer in cells and thus necessary for life to exist (Reid, 1961). If phosphorus (phosphate) is in very low concentrations in a be of water, it may act as a limiting factor. The mean total phosphorus content of most lakes ranges from about 10 to parts per billion 1961). The phosphate values obtained for the four bE vary greatly. Sodus Bay (190 ppb) contained the least followed by Little Sodt Bay (320 ppb), Port Bay (750 ppb), and Irondequoit Bay (1100 ppb). Thus, it j apparent that the phosphate values for the bays studied were extremely high, especially for Irondequoit Bay. There appears to be two factors which enter into the variation in phosphE content of the bays. The first is the human activities in the watershed and t second is the size of the bay. Since the areas surrounding Little Sodus Bay, Bay, and Sodus Bay are all similar in human activity (agriculture) it is like] that the volume of water in each determines the phosphate concentration-the larger the the greater the dilution of phosphates, and the lower the concentration. Based on this, it could be predicted that Sodus Bay would haVE the lowest phosphate concentration followed by Little Sodus Bay and Port Bay j that order. This is the condition depicted by the results (see Tables 9 and ] This, of course, does not take into consideration the size of'the watershed, t poor sewage treatment conditions for the camps, or the decomposition at the be and in the marshy.areas. Neil, Johnson, and Owen (1967) state that "the chief sources of fertilitJ (nitrates and phosphates) of the Great Lakes are land drainage and sewage effluents." It is doubtful if sewage effluent could cause the entire phosphat content in Little Sodus Bay, Port Bay, and/or Sodus Bay due to the scarcity oj populated areas around these bays. However, raw sewage does enter the bays fl the surrounding areas. This area, as Berg (1963) points out, is known as the "Fruit Belt." name is derived from the fact that many orchards are located here due to the moderating effect of the lakes on the weather. It is probable that fertilize] are used in these orchards and thus, this is likely to be a major source of pl phates for Little Sodus Bay, Port Bay, and Sodus Bay.
29 Irondequoit Bay differs from the other three bays in that its watershed is populated by over 100,000 people (Wilson, et al., 1969). Sewage is a major source of nitrates and phosphates (Neil, et al., 1967). Forest (1968) states that besides high concentrations of phosphates, coliform counts indicating serious fecal pollution were also found. Thus, it is probable that sewage is a major source of phosphates in Irondequoit Bay. Another major source of phosphates in a metropolitan area would be from the use of detergents. Heinke (1969) states that "in the United States, detergents contribute more than twice as much phosphorus as human waste." Phosphates may comprise as much as fifty percent by weight in detergents and are used because of their synergistic or "wetting" effect in hard water. Thus, in a populated area, detergents may act as a major source of phosphates. CONCLUSIONS From the study of Little Sodus Bay and Port Bay on the 20 of August, 1970, and Sodus Bay and Irondequoit Bay on the 21 of August, 1970, it was determined that all the bays show characteristics associated with eutrophication. The highest rate of eutrophication was found in Irondequoit Bay, followed by Port Bay Little Sodus Bay, and Sodus Bay. Factors contributing to eutrophication are size of bay and human activity in the watershed. Effluent from the city of Rochester, New York, is the major cause of the extreme eutrophication of Irondequoit Bay. The quality of the water has deteriorated during the past thirty years. Port Bay's eutrophic condition is due to its relatively small water volume. Little Sodus Bay's inter-change with Lake Ontario is probably important in lessening its rate of eutrophication while the large size of Sodus Bay is the prime factor in retarding its rate of eutrophication. REFERENCES Arnold, D. E. 19710 Lake Erie Alive But Changing. The Conservationist. Vol. 25, No.3. NYS Dept. of Environmental Conservation, Albany, N.Y. Berg, C. o. 1963. Middle Atlantic Limnology In North America, Edited by David Go Frey. The Univ. of Wis. Press. Birge, E. A., and C. Juday. 1929a. Penetration of solar radiation into lakes, as measured by the thermopile. Bull. Natl. Research Council, 68:61-76. -----. 1929b. Transmission of Solar radiation by the waters of inland lakes. Trans. Wise. Acad. Sci. Arts Lett., 24:509-580. -----. 1930. A second report on solar radiation and inland lakes. Trans. Wise. Acad. Sci. Arts Lett., 25:285-335. -----. 1931. A third report on solar radiation and inland lakes. Trans. Wise. Acad. Sci. Arts Lett., 26:383-425.
30 -----. 1932. Solar radiation and inland lakes. Fourth Report. Observations of 1931. Trans. Wise. Acad. Sci. Arts Lett., 27:523-562. BUbeck, R. 1970. Water temperature and dissolved oxygen The Rochester Committee For Scientific Information, Rochester, N. Y. Dobson, H. H. 1967. Principal ions and dissolved oxygen in Lake Ontario. Proc.-Tenth Conf. on Great Lakes Res. Int. Ass. for Great Lakes Res., Ann Arbor, Michigan. Forest, H. S. 1968. Landfills threaten Irondequoit Bay. The Rochester Comm. For Sci. Inf., Rochester, N. Y. Heinke, G. W. 1969. Hydrolysis of condensed phosphates in Great Lakes Waters, Proc.-Twelfth Conf. On Great Lakes Res. Into Ass. for Great Lakes Reso, Ann Arbor, Michigan. McKee and Wolf. 1963. Water quality criteria, California State Water Quality Control Board. Neil, J. H., M. G. Johnson and G. E. Owen. 1967. Yields and sources of nitrogen from several Lake Ontario watersheds. Proc.-Tenth Conf. On Great Lakes Res. Int. Ass. for Great Lakes Res., Ann Arbor, Michigan. Owmber, C. R. and D. A. Kee. 1967. Chlorides in Lake Erie. Proc.-Tenth Conf. I' On Great Lakes Res. Int. Ass. for Great Lakes Res., Ann Arbor, Michigan. Powers, C. F. and A. Robertson. 1966. The aging Great Lakes. Scientific American, Rainwater, F. H. and L. L. Thatcher. 1960. Methods for collection and analysis of water samples. Geological Survey Water Supply Paper 1454. u. S. Government Printing Office, Washington, D. C. I' Reid, G. K. Ecology of Inland Waters and Estuaries, Reinhold Pub. Corp. New York. Ruttner, F. 1963. Fundamentals of Limnology. Univ. of Toronto Press, Toronto, Canada. Schomer, H. A. 1934" Photosynthesis of water plants at various depths in lakes of northeastern Wisconsin o Ecology, 15:217-218. Schomer, H. A. and C. Juday. 1935. Photosynthesis of algae at different depths in some lakes of northeastern Wisconsin. I o observations in 1933. Trans. Wise. Acad. Arts Lett., 29:173-193. Skoch, Edwin J. and N. W. Britt. 1969. Monthly variations in phosphate, and related chemicals found in the sediment in the island area of Lake Erie 1967-68 with reference to samples collected in 1964, 1965, and 1966, Proc.-Twelfth Conf. on Great Lakes Res. Int. Ass. for Great Lakes Res., Ann Arbor, Michigan.
-l 1 31 1 Theroux, F. R., E. F. Eldridge, and W. L. MaIlman. 1943. Laboratory manual .for chemical and bacterial analysis of water and sewage. McGraw Hill Book Co., Inc., New York. Tressler, W. L., T. S. Austin, and E. Orban. 1953. Limnological factors in Irondequoit Bay. Am. Midland Nat. Weiler, R. R., and V. K. Chawla. 1969. Dissolved mineral quality of Great Lakes waters. Proc.-Twelfth Conf. on Great Lakes Res. Int. Ass. for Great Lakes Res., Ann Arbor, Michigan. Welch, P. S. 1952. Limnology, Sec. Ed., McGraw Hill Book Co., Inc., New York. Wilson, D. J., J. E. Hubard, R. Stewart, and G. G. Berg. 1969. Eutrophication of Braddock Bay. I. nutrients from Brockport, The Rochester Committee for Sci. Inf., Rochester, New York. ] -1 1 ., -
32 The Distribution of Microcrustaceans at the Mud-Water Interface of Little Sodus Bay l By Robert AQ Spafford* INTRODUCTION Vertical diel migrations of various zooplankters have been observed and studied by a large number of people for a number of years. Many of these studies have included the distribution of microcrustaceans throughout va!ious _levels of the water column. Studies concerning this distribution of :populations in the water column include those made by Cushing (1951), Davis (19'55), Woodmansee and Grantham (1961) and Hazelwood and Parker (1961). Other published reports have dealt with the distribution of zooplankters in the benthic environment Some of these benthic studies have shown that microo crustaceans frequently inhabit anaerobic conditions, either below the substrate, or in the water column, at, or near, the mud-water interface. Observations of microcrustaceans living under these anaerobic conditions were made as early as sixty years ago by Juday (Moore, 1939). Subsequent studies that reveal similar observations have been reported by Moore (1939), Eggleton (1931), Deevey (April, 1941), and Woodmansee and Grantham (1961). Woodmansee and Grantham (1961) found that, in one study made by them, a zooplankter, Mesocyclops edax, was present in well oxygenated regions of the water column at certain times of the day, roughly 'corresponding to a period from sunset to sunrise. They hypothesized that edax moved into the oxygenated regions from either the benthic or hypoplanktonic regions, both of which were well within the area of completely depleted oxygen of the lake being studied. It has been further hypothesized that many microcrustaceans may concentrate at the mud-water interface during relatively long periods when this zone is completely devoid of dissolved oxygen. Deevey (Oct., 1941) reports that "no metazoan has been shown to carry on1 autotrophic anaerobic respiration under laboratory conditions Nothing has been found in a of the more recent literature that would contradict this finding, although it is a well known observation that various unicellular and subcellular forms of life are apparently well adapted to survival in an oxygenless environment0 In his report on marine bottom samples, Lackey (1961) concludes that much more emphasis needs to be placed on the study of, and the importance of, the mud-water interface and the biochemical exchanges that occur there. Because of the observations made by several of the authors previously cited in this section, it would appear that a similar need exists in relation to fresh-water environments. *Submitted as partial fulfillment for the Master of Science Degree in Education under the advisement of R. A. Engel.
33 Kinne (1964) states that "most of our knowledge on adaption in Crustacea is based on results obtained on macroscopic forms, especially decapods. Ther' a great need for information on smaller forms such as ostracods, copepods, cirripeds, and the like." The same author goes on to report that "in spite 0 considerable literature on respiration in Crustacea, little is known about acclimation to different levels of oxygen and carbon dioxide." There appears to be a definite lack of information concerning the relati, ship and possible importance of the mUd-water interface to the distribution 0 microcrustaceans and their apparent ability to withstand significant periods, extremely low, and sometimes, totally zero oxygen tensions. If further work is to be done in the area of the mud-water interface, it is important that techniques be developed for obtaining representative sample: from the extremely narrow band that often forms the interface. Lackey (1961) points out that one of the major problems involved in surveying the populatioJ of this particular environmental niche, is that of securing a representative sample from an undisturbed mud-water interface. He further points out that "this becomes increasingly difficult" when one cannot conveniently see the ZOJ that is being sampled. Various attempts at using dredges and cores have been tried. Both of these methods may work adequately well for sampling benthic environments, but often produce samples that are less than desirable from the mud-water interface (Frolander and Pratt, 1962) because they sample too deep or yield too few organisms mixed with large quantities of sediment. [, At this point it might become apparent that scuba diving might be a mean of securing representative samples, since the diver would be able to actually see the area that is being sampled. Perhaps, under certain ideal conditions, this would be the most satisfactory approach to the problem of securing sampl However, several drawbacks soon become apparent. For example, even when trai divers are available, they are limited as to the depth that can be reached. Furthermore, temperature in deepwater and during the colder seasons becomes serious limiting factor. It may also be questioned as to whether or not the can secure a sample without disturbing the "delicate" environment at the mud-interface. It, therefore, seems desirable that some convenient methods be developed obtaining adequate numbers of representative organisms from a relatively undi portion of the mUd-water interface. It would be desirable if these methods a techniques could be used in any depth and at any season of the year, particul in the colder climates. With the above factors in mind, the main objectives of this project were as follows: 1. To develop a device that would permit the obtaining of a representat sample of populations, microcrustaceans in particular, inhabiting the mUd-water interface; 2. To devise a method of obtaining an accurate determination of the oxygen at the mud-water interface; 3. To test the above sampling devices and techniques; and
34 4. To conduct a search of the literature for reports of studies pertaining to the sampling of chemical, physical and biological factors, and anaerobic conditions at and near the mud-water interface. It is appropriate at this time to express appreciation to Mr. J. Eddy Demers for his valuable assistance in the field work of this project, particularly his abilities as a scuba diver.1 SAMPLING TECHNIQUES -ZOOPLANKTERS: The device illustrated in Figure 1 was rather simple and inexpensive to construct. A few materials were purchased locally, but most were obtained from an accumulation of materials on hand. It consists, basically, of a bulb type rectal syringe (obtainable in any drug store) contained within a plastic housing to which the trigger mechanism is attached. A length of rubber tubing is connected to the syringe at one end, with the other end inserted into a 2 inch length of stiff, plastic tubing, which in turn, is held in place by a spring type metal clip. The clip slides in a slot in the plastic housing so that the level and angle of the tube opening is completely adjustable. A piece of metal plate was added to the bottom of the complete unit to add a sufficient amount of weight to make the device relatively stable. The triggering mechanism consists of a simple hose clamp that is closed manually at the surface and opened upon being struck by the messenger which is released after the device is in position on the bottom. Before being lowered, the syringe bulb is compressed as much as possible and the hose clamp closed to prevent the bulb from filling with air. During the last meter, before reaching the bottom, care should be taken to lower the unit as gently as possible so as to minimize of the mud-water interface. After the device is in position, the messenger is released and sufficient time is allowed to permit the bulb to fill with water before raising the unit to the surface. Experimentation indicates the length of time required for the bulb to fully expand, as it depends on the size of the bulb and the diameter of the tube opening. It should be noted at this point that, during a search of the literature .. following the development of the above described device, it was found that the] I device was remarkably similar to an "ooze sucker" originally developed by Rawson (1930) and subsequently modified by Moore (1939). '1 Upon being brought to the surface, the water in the bulb is transferred to.' glass stoppered bottles or jars by detaching the tubing from the clip, placing it in the container and squeezing the bulb. It is a good idea to be sure all the water is extracted from the bulb and tubing, either by repeated squeezings, or by rinsing thoroughly with clear water, before taking the next sample. The bulb used by the author in constructing the sampling device consistantly delivered a sample of from 185 mI. to 190 mI., large enough to obtain a representative sample, but not so large as to require undue time in counting organisms The author transferred the collected water samples directly from the sampling device to 200 ml. screw top, wide-mouth jars. A sufficient amount of 10% formalin was added to kill the zooplankters, which settled to the bottom over a period of 12 to 24 hours. The samples were then examined by decanting off the water with a 25 ml. pipette, starting at the surface. Each 25 mI. subsample was examined in a
lD -,, e '. \ t \ \ \ \ I:I .; . I" II Ii I, ,Iii, ,"ii .' I' i: !' i' i' ,i i" Ii 35 CD C) g c. C ,<1-CD C.-a. '-!.c Ei 0) .c E :J .c'm!c :J CD:J._ CD+Jm ,-' 0!'--0 I Q. CJ) '-0 1'\" Ci cO) +-" ..... CD .-.0 0) I 0) 0 0)' :-::' '-.Q CD i Q. -0 .c o '>:J 0 0 C::Jo (f) a: I a: UJI+J -: C'J'cr5 Ld CO i FIGURE 1
36 petrie dish under a dissecting microscope, but usually no plankters were found in any subsample above the bottom 25 ml. or 50 ml. SOME COMMENTS ON THE SAMPLING DEVICE: It has previously been mentioned that the device described is very similar, in principle, to one developed by Rawson and subsequently modified by Moore. In his report, Moore (1939) states that "this ooze sucker was the most satisfactory instrument for qualitative collections. However it is not suitable for quantitative work since: (1) it disturbs the finely divided ooze as it settles onto the bottom; (2) it collects only those organisms near the surface of the deposits; and (3) its efficiency is probably different on muck bottom and on sand bottom." It should be pointed out here, that Moore's studies were concerned primarily with the benthic fauna of the lake being studied, rather than specifically with the mud-water interface. Therefore, his criticism that the ooze sucker collects only those organisms near the surface of the deposits does not seem to be a valid one when it is the mUd-water interface from which the sample is intended to be taken. Moore's criticism that the ooze sucker disturbs the finely divided ooze as it settles to the bottom is probably valid and would also apply to the device developed for this project. However, if a large diameter ring, such as that used on Moore's own device, were attached to the sampler to support the mechanism on the bottom at a distance considerably away from where the sample was actually being taken, this defect should be overcome, or at least minimized. A ring with a diameter of no more than two feet should be sufficient, based on the calculations of the actual area from which a typical sample is drawn, as discussed subsequently in this report. It is felt that the design of Moore's device would be greatly improved by the omission of the funnel-like structure at the end of the collecting tube. It would ,appear that the funnel, itself, would cause a good deal of disturbance and deflection of water and organisms away from the collecting area. Moore's final criticism, that regarding the difference of efficiency on different types of substrates, is a valid one and should be considered whenever quantitative data is desired. However, the difference in efficiency may, or may not, be as great when samples are desired from the interface rather than from the benthos. An attempt has been made to determine the area from which the sample collected by the sampling device is drawn. Assuming that water taken into the sampler is being drawn equally from all directions, because of equal pressures, then, if the hose'was positioned with the opening essentially on the bottom, water taken in would be drawn from a hemisphere with the flat base formed approximately on the substrate. The hemisphere would have a radius of approximately 4.5 cm. by way of the following calculation: = 190 cc. (190 cc. being an average sized sample)
I 37 Thus, if the hose were positioned so that the opening was on the bottom, or essentially so, the maximum amount of water would be drawn from the lowest portions of the hemisphere, as illustrated below: e = .5 cm. thick 1 cm. thick 1 cm. thick 1 cm. thick 1 cm. thick Layer "a" represents approximately 32% of the total sample Layer "b" represents approximately 28% of the total sample II LB\Yer "c" represents approximately 22% of the total sample -, Layer d" represents approximately 14% of the total sample Layer "e" represents approximately 4% of the total sample Theoretically, the area of the substrate from which samples are removed by this 2 2 method would be about 64 cm, or about .0064 m, the area of the flat base of a hemisphere having a radius of 4.5 cm. This would appear to be the ideal position for the hose, since the maximum distance from which the water would be drawn would be a 4.5 cm. above the mud-water interface and would collect the greatest amount of water possible from the interface itself. Using the latter method, with the opening of the hose less than 1/2 cm. above the bottom of an aquarium tank containing highly turbid water, suspended particulate matter beyond about 4 cm. above, and lateral to, the opening did not seem to be noticeably disturbed by the intake of water into the sampler. This would appear to be consistant with the theory outlined previously. During the course of this project, the question asto what thickness is to be given to the mud-water interface could not be avoided. Obviously, the interface cannot, under most natural conditions, be considered to be sharply delineated, as the water coming into contact with the flat, glass bottom of an aquarium tank. In any natural body of water, depending on currents, general turbulence and type of substrate, there could reasonably be expected to be some degree of intermingling of particulate matter forming the substrate with the lowest layers of water. The zone of transition from water to mud could, conceivably, extend from a few millimeters to several centimeters in thickness. While the interface is, indeed, a difficult zone to define, it, I believe, can be assumed that the more dense the substrate, the more sharply defined will be the zone-comprising the transition from water to substrate. For example, solid rock and sand would normally create a more sharply defined interface than would muck or fine silt. Also, considering that the species of microcrustaceans being stUdied are capable of varying degrees of locomotion, and the fact that the contact of the water sampler with the substrate would cause some degree of turbulence and disturbance of the habitat, however slight, it is felt that a sample inclUding water taken from no more than 4.5 cm., or even 5 or 6 cm., above the substrate could be considered representative. Also, since we are concerned here with the apparent ---------
38 ability of these microcrustaceans to live in a completely deoxygenated zone, the zone of depleted dissolved oxygen would, in many cases, extend far above the 4 or 6 cm. from which they are being taken by this method of sampling. In concluding these remarks on the validity of the sampling device for quantitative purposes, it should, also, be pointed out that, even though it may not provide for a completely representative quantitative sample, it would certainly be adequate for comparative studies as to the relative number of organisms at the mUd-water interface at different times. This conclusion is made on the basis that the volume of the sample collected is always about the same and that it can be assumed that each sample would be drawn from a similarly shaped hemisphere of water. Thus, one should be able to use the device to observe any significant increase or decrease in populations in a series of samples taken over a period of time SAMPLING TECHNIQUES -OXYGEN: The device that was developed for the collection of zooplankters from the mUd-water interface is not suitable for collecting water samples for oxygen analysis by the Winkler method because of there always being a certain amount of air trapped in the bulb and/or rubber hose. Additional sources of error in trying to secure an accurate determination of the dissolved oxygen could be incurred as a result of the presence of oxidizing and reducing substances which are frequently encountered at and near the substrate (Beadle, 1958) and from the presence of silt and other "dirt" contaminating the water sample. Techniques have been developed by several people that attempt to overcome some of the problems mentioned above. Some techniques that might be modified for adaption to collecting water samples at the mud-water interface for oxygen analysis have been published by Cole (1932), Beadle (1958), and Ericksen (1963). However, Fremling and Evans (1963) have developed a method of obtaining clean water samples for oxygen analysis at the mudwater interface which would be suitable for this type of study. The method devised by Fremling and Evans consists of a polyethylene bag filled with tap water and sealed with rubber bands. The water filled bag is lowered to the bottom and, since polyethylene is permeable to oxygen, diffusion will continue until the partial pressure of dissolved oxygen is the same inside the bag as in the natural water on the outside. The bag is then raised to the surface and the water inside is analysed by the Winkler method. In trying to utilize this method of determining the dissolved oxygen concentration, several problems were encountered and subsequently overcome. First, it was found that most of the commercial polyethylene bags (Glad Bags, Baggies, bread wrapper, etc.) readily developed leaks at the seams. Out of 17 plastic bags, representing 4 different kinds and types, all were found to develop leaks in the seams during the process of filling and closing the bag. The presence of holes, of course, causes the bag to lose most of its water and "go flat", as was, apparently, the case several years ago when this method was tried by another Oswego student. The problem of leakage was overcome by reinforcing the side seams and the bottom of the bag with thin, plastic, electrician's tape. The possibility of developing leaks is also substantially reduced by not completely filling the bag with water, but filling it only about half way. This reduces the pressure on the seams, as well as allowing the bag to lay more flatly on the substrate.
39 ::; I .1 I I I, I' iiI, ii,i Ii 'i'I III ,I !\ I Of course, no air can be allowed to remain in the bag if accurate dissolved oxygen analysis is to be expected. This is best accomplished, as Fremling and Evans suggest, by placing the half-filled bag in a bucket of water, or the lake, if surface lake water is being used to fill the bag, and sealing the top opening underwater with rubber bands, after all the air has bubbled out. Because it takes 30 to 48 hours for the water on the inside of the bag to reach an equilibrium with that in the lake, it will usually be necessary to mark the position of the bag with a bouy, or some other type of marker, so that it can be retrieved at a later time. Since Little Sodus Bay, the area under consideration in this project, is navigable by large boats and is heavily used during the summer months, it was impractical to use a floating type marker. As a result, this method of determining the dissolved oxygen at the mUd-water interface was not used at the area being studied. Perhaps a marker that was submerged, but still visible and retrievable from a boat, would be a solution to this problem. However, the above described method was used in another lake (Millsite Lake, Jefferson County, New York) to determine if it could be utilized in future studies of the mUd-water interface. The following data and 'results were obtained: A polyethylene bag (Glad Bag, manufactured by Union Carbide Corp.), with a capacity of about two quarts, was reinforced and filled about half way with tap water having a dissolved oxygen concentration of 7.4 ppm. The bag was then suspended at a depth of one meter in water that had a DO of 9.6 ppm. After a period of 38 hours, the bag was retrieved and the water analysed. The water in the bag was found to have a DO of 9.3 ppm, and a second analysis of the lake water taken at the time of retrieving and again at a depth of one meter, produced a DO of 9.3 ppm. From the results obtained in this one trial, it would appear that the method would be suitable for oxygen analysis at the mud-water interface of Little Sodus Bay, providing the problem of marking the location of the bag can be overcome. The water samples collected for actual oxygen analysis in this initial study were collected in a Kemmerer Water Sampler carried to the mud-water interface and held horizontally, just above the substrate, by a scuba diver. Care was taken not to disturb the mud, to avoid including dirt in the water sample. The Kemmerer sampler was then closed manually and hauled to the surface where the sample was fixed immediately. Final DO concentrations were determined in the lab within 2 hours of collecting by the Winkler method. SOME COMMENTS ON OXYGEN SAMPLING: It might appear that the modified Fremling and Evans technique might be inconvenient to use because of the long duration of time required for equalization of oxygen partial pressures to occur. This COuld, indeed by a serious drawback to the technique. However, it should also be pointed out here that once summer stagnation sets in and a zone of zero dissolved oxygen has been formed, it usually remains for a period of time and it may not be necessary to check the amount of dissolved oxygen each and every time a population sample is taken from the same location, once it has been determined that zero oxygen conditions do exist. Or, perhaps a series of oxygen analysis at regular time intervals ,could be made as a check on the dissolved'oxygen in'the area.
l 40 According to data published by Fremling and Evans in, their report, this sampling technique resulted in measurements that were within 0.2 ppm of measuremehts obtained with mechanical samplers. This amount of error is very close to the amount of error found to be present in the Winkler method of analysis, which, according to Carpenter (1965), is 0.10 ppm. It is felt that the apparent accuracy of the technique and the fact that it enables a clean sample to be obtained from a narrow band at the mud-water interface, much of the objection concerning the time required to obtain a sample is overcome. RESULTS: Physical -Chemical Data: Date: July 30, 1970 Location: Little Sodus Bay, Lake Ontario, Fair Haven, New York Time: 11:30 am -1:00 pm Air Temperature: 80F. Depth: 10.5 meters Dissolved Oxygen: 0.0 ppm Biological Data: a) The first sample was taken with the sampling device described. The unit was carefully lowered to the bottom and opened. The total sample consisted of a volume of 185 ml. The intake opening was in a horizontal position at the lowest end of the adjustment slot. The sample was transferred to a 200 ml. jar and fixed within 2 hours of collection by the addition of 10% formalin. Upon examination of the sample, the following microcrustaceanswere observed: Cladocera (Bosmina) -52 Copepods (Cyclops, Mesocyclops and Diaptomus; The majority of individuals were immature and there was 1 gravid female.) 65 Ostracods Theae were very numerous and no attempt was made to determine the actual number. b) The second sample was taken by a scuba diver descending to the bottom and placing an open, clear, plastic tube, 5.0 em. in diameter into the substrate about 3 cm. The ends of the tube were then plugged with rubber stoppers and the tube brought to the surface. Within 2 hours the water was decanted off (approximately 2 -3 Mm. of the uppermost layer of silt was included) and transferred to a 200 ml. jar. The volume of this sample was 136 ml. The sample was then fixed by addition of 15% formalin. This sample was taken for comparative purposes. The following observations were made: Cladocera (Bosmina) -4 Copepods (Cyclops, Mesocyclops, Diaptomus; The majority of individuals were immature and there were 2 gravid females.) 58 Ostracods -These were very numeroUs and no attempt was made to determine the actual number.
41 c) The following data was then calculated: Sample #1: Cladocera 281/liter Copepods 351/liter Sample #2: Cladocera 29/1iter Copepods 427/1iter Sample #1: Cladocera 8,112/m2 of substrate Copepods 10,140/m2 Sample #2: Cladocera 2,000/m2 Copepods -29,000/m2 COMMENTS ON RESULTS: There appears to be little correlation between the numbers of individuals collected with the two sampling techniques, particularly when projected to a concentration per meter2 One explanation that can be offered for the discrepancy is that many of the copepods observed in Sample #2 may have initially been located in the substrate and emerged into the water column between the time of collection and fixing, two hours later. It might, also, be noted here that the cladocerans seemed to be much more numerous in Sample #1 than in Sample #2. Perhaps, being somewhat smaller in size, and less motile, than the copepods observed, they were more readily drawn into the bulb than were the copepods. DISCUSSION: One of the stated objectives of this project was to conduct a search of the literature for previously published studies which might provide findings and information relative to an investigation of microcrustaceans irthabiting the mudwater interface and their apparent ability to survive periods of extremely low, or non-existent, dissolved oxygen. While there is considerable published information concerning the respiratory requirements, habits and adaptions of many macroscopic forms of life, including the larger forms of Crustacea, there appears to be minimal information available concerning the respiratory requirements, and habits related thereto, of microscopic forms of Crustacea. It has, also, been found' that a considerable amount of the available findings relating to the problem are a result of laboratory investigations, rather than in situ studies (Comita, 1965) Woodmansee and Grantham (1961), after finding a significant portion of a population of Mesocyclops edax in 02 free waters throughout several 24 hour periods conducted a brief laboratory investigation and found that M. edax was apparently able to survive' in oxygen-free water for at least 6 hours ,-bu't"COuld not survive in the same environment for 12 hours. Another study (Hazelwood and Parker, 1961) indicates that the number of Daphnia is positively correlated with dissolved oxygen concentrations and that Daphnia apparently requires a minimum concentration of approximately Img/l for survival. Deevey (Oct., 1941) reports that although many of the profundal bottom inhabitants, including several species of microcrustaceans, of eutrophic lakes are apparently able to perform respiration successfully at extremely low oxygen tensions and which reach zero at intervals of
42 several days, prolonged exposure to oxygen-free environments is evidently fatal. Eggleton (1931) states that "evidence now 'available indicates that the members of the profundal benthic fauna are facultative rather ,than obligatory 'anaerobes' and that they endure rather than select an anaerobic environment." If this is the case, what adaptions are the members of this fauna able to make in order to survive this severe condition for what appear to be long periods of time? There are many reports that several of the microscopic Crustaceans are able to encyst themselves as an effective means, apparently, of surviving anaerobic conditions (Moore, 1939; Deevey, April, 1941; Deevey, Oct., 1941). However, there are also reports, (Deevey, April, 1941) that a prolonged oxygenless environment does not prevent emergence from the encysted condition of Canthocamptus staphlinoides Pearse. It seems that, although encystment may be an effective method of enduring oxygenless conditions, it may not be entirely induced or controlled by the mere depletion, or even the complete lack, of oxygen, but rather a combination of factors. Another, apparently, effective means of enduring severe oxygen stagnation may be an adjustment of metabolism. Irving (1964) states that "specialization of animals, adapting certain species to environments that vary periodically or occasionally in 02 supply, provides a great diversity of examples of the time dUring which their metabolism can accelerate or even proceed before the 02 supply must be made up through the lagging respiratory exchange." The implication here is, I believe, that an oxygen debt is created periodically, and then consumed during period of low, or depleted oxygen. This would concur with the findings of Woodmansee and Grantham (1961). Evidently, during the period of depleted oxygen, the metabolism of many organisms is reduced. Irving (1964) found that the metabolic rate of Gammarus limnaeus, a common amphipod, was less during periods of depleted oxygen than during periods when the dissolved oxygen was abundant. Kinne (1964) has found that aquatic crustaceans, in particular, are faced with problems of low oxygen pressures. He reports that certain species of Daphnia are able to synthesize additional amounts of hemoglobin when kept in water of low 02 pressure for a period of days. He also reports similar adjustments of respiratory pigments in other Cladocera during periods of depleted oxygen. Kinne goes on to emphasize that these functional changes may be expressed as a result of either genetic or nongenetic adaptions, and that these adaptions "may be effective continuously or during limited periods only; may persist beyond immediate usefulness; and may be different in different life-cycle stages." Upon completing this initial search of recent literature on the subject, it has become even more obvious than at the outset, that a great many questions remain to be answered about the chemical, physical and biological relationships that may exist at the mud-water interface of fresh-water Qodies. This project has merely tried to point out, and attempt to solve, some of the technical problems that have limited study of the interface in the past. It has, also, attempted to point out and define some of the problems of adaption with which some organisms inhabiting low oxygen conditions at the mUd-water interface are faced. SUMMARY: Devices and techniques have been developed and modified, and suggestions have been made for this improvement. While it is obvious that the device developed for the sampling of zooplankters may have certain shortcomings, it is felt that it does
------succeed in obtaining a sample of water.from a relatively narrow band, just above the sUbstrate. While the samples collected may not be 100% accurate, quantitatively," it does appear to obtain a representative sample, qualitatively, since there were no organisms observed in Sample #2 that were not present in Sample #1. Further, it can be assumed, I believe, that if the device is used in a consistant manner at all times, the type of, and amount of, error will be more or less constant. It would, therefore, follow that samples collected at different times can be compared relative to each other for a valid quantitative analysis. An initial review of the pertinent literature has been made in an attempt to define some of the problems concerned with the mud-water interface. As a result of this project, a base has been prepared from which further investigation can be pursued with greater depth and more extensive field observationa REFERENCES: Beadle, L. C. 1958. "Measurement of Dissolved Oxygen in Swamp Waters. Further Modification of the Winkler Method." J . of Exper. BioI., 35: 556-566. Carpenter, James H. 1965. "The Accuracy of the Winkler Method for Dissolved Oxygen Analysis." Limnol. and Oceanog., 10:135-140. Cole, Arch E. 1932. "Method for Determining the Dissolved Oxygen Content of the Mud at the Bottom of a Pond." Ecology, 13:51-53. Comita, Gabriel W. 1965. "Oxygen Uptake in Diaptomus siciloides Lilljeborg." Limnol. and Oceanog., 10:466-468. Cushing, D. H. 1951. "The Vertical Migration of Planktonic Crustacea." BioI. Rev., 26:158-192. Davis, C. C. 1955. "The Marine and Fresh-Water Plankton." Michigan State University Press. Deevey, Edward S. 1941. "Notes on the Encystment of the Harpacticoid Copepod Canthocamptus staphylinoides Pearse." Ecology, 22:197-199. April, 1941. 1941. "Limnological Studies in Connecticut." Ecol. Mono., 11:413-455. October, 1941. Eggleton, Frank E. 1931. "A Limnological Study of the Profundal Bottom Fauna of Certain Fresh-Water Lakes." Eco1. Mono., 1:231-331. Eriksen, Clyde H. 1963. "A Method for.Obtaining Interstitial Water From Shallow Aquatic Substrates and Determining the Oxygen Concentration." Ecology, 44:191-193. Fremling, C. R. and J. J. Evans. 1963. "A Method for Determing the Dissolved Oxygen Concentration Near the MUd-Water Interface." Limno1. and Oceanog., 8:363-364. '"'. =s:m:;:aa 3
iI 44 Frolander, H. F. and Ivan Pratt. 1962. "A Bottom Skimmer." Limno1. and Oceanog., 7:104-106. Hazelwood, Donald H. and Richard A. Parker. 1961. "Population Dynamics of Zooplankton." Ecology, 42:266-274. Irving, Laurence. 1964. "Comparative Anatomy and Physiology of Gas Transport Mechanisms." Handbook of Physiology, Section 3: Respiration, Vol. I. Ed. Fenn and Rahn; American Physiological Society, Washington, D. Co Kinne, Otto. 1964. "Animals in Aquatic Environments: Crustaceans." Handbook of PhYsiology, Section 4: Adaption to the Environment. Ed. Dill, Adoh and Wilbur; American Physiological Society, Washington D. C. Lackey, James B. 1961. "Bottom Sampling and Environmental Niches." Limnol. and Oceanog. 6:271-279.I Moore, George M. 1939. "A Limnological Investigation of the Microscopic Benthic Fauna of ,Douglas Lake, Michigan." Ecol. Mono., 9:537-5820 ( Rawson, Donald S. 1930. "The Bottom Fauna of Lake Simcoe and Its Role in the Ecology of the Lake." Univ. Toronto Studies, BioI. Series; 34:1-183. I Woodmansee, R. A. and B. J. Grantham. 1961. "Diel Vertical Migrations of Two Zooplankters in a Mississippi Lake." Ecology, 42:619-628. lI l I t. l l b.
45 If ;1 i!Phosphate and Nitrate Study in Little Sodus Bay, New York During Winter Ice Cover and Early Spring, 1972 By Kathleen Del Prete* INTRODUCTION The purpose of this study was to measure nutrient concentrations in Little Sodus Bay during winter ice cover and early spring conditions. The nutrients under study included nitrates and various forms of phosphate. Three sampling periods were chosen, with three depths sampled each time, to follow the nutrients both periodically and vertically. One sample obtained during the second sampling .date to follow horizontal nutrient concentrations within the bay. The values obtained in this study may be related to companion studies on the zooplankton and benthic populations during this same time period. Also, the phosphate concentrations may be compared to values obtained at other times of the year to give a general indication of the nutrient relationships within the bay. No effort was made in this study to relate nutrients and productivity, except for observations made in the sample collections and the course of the chemical analyses. MATERIALS AND METHODS Samples were collected with a plastic Kemmerer sampling device, refrigerated and stored in plastic bottles for analysis. Analyses were carried out in accordance with Standard Methods (Thirteenth Edition, 1971): a cadmium reduction was used for nitrate analysis, and the molybdate blue method with an extraction step was used for phosphate analysis. Soluble and particulate phosphate was determined by filtration through a .45p Millipore membrane filter. The first two sampling dates were conducted during ice cover on the bay, the Kemmerer being lowered through a hole in the ice and taken first at the surface (0 meters), intermediate (4 meters), and bottom (7 meters) depths. Storage bottles for the phosphate determinations had been previously washed in a 10% HCl solution, as was all glassware used in the phosphate analysis. No special treatment was given the nitrate sample bottle, and after the first sampling period all samples to be analysed were carried in these acid-rinsed bottles; this was done only for convenience in transporting samples. Nitrate analysis was performed the same afternoon as sampling using a cadmium reduction with Hach chemicals (2 NitraVer IV pillows/50 ml sample) and colorimetric analysis in the Bausch and Lomb Spectronic 20 Colorimeter/Spectrophotometer using 1" tubes at It was felt that nitrate represented the major nitrogen complex in the bay waters, and so, analyses for nitrite or ammonium nitrogen were not performed. IL !-*Submitted as partial requirement for Problems in Advanced Limnology, Bio. #298, taught by R. A. Engel.
46 Phosphate analysis was conducted using an isobutanol-benzene extraction step with the molybdate blue method. Soluble phosphate was determined after filtration through a o45p Millipore membrane filter; this filtration step was performed within two to three hours after sample collection, except for the first sgmpling date when a two day delay occurred. Prior to analysis samples were refrigerated in acidwashed plastic bottles. Double distilled water blanks were subjected to the same treatment as were the samples. Samples of 200 to 300 ml volume were used for total phosphate analysis, employing an acid digestion step. Extraction with isobutanol-benzene followed, and 50 ml samples were read after a l5-minute color development period at 625 mp. Orthophosphate analysis was attempted with a 200 ml sample following the first sampling date o However, the phosphate concentrations were too low to be accurately measured, having over 97% transmittance. Optimal Spec. 20 transmission falls within the 20% to 80% range. A larger sample volume was attempted using standard phosphate concentrations (up to 500 ml volume) with the standard 50 ml isobutanol-benzene extractant and also with a proportional increase in the extractant, but neither method proved satisfactory (Table I). Phosphate determinations were thus limited to total phosphate concentrations: total soluble, total particulate and soluble, and total particulate phosphate. Table I Results of Experimentation of Orthophosphate Methods Against Known Standards. a Using standard procedure (50 ml isobutanol-benzene and 15 ml.molybdate II)o Standard Volume Transmittance Measured (p) (p) ppm. (ml) (%) ppm. 0.1 200 58.5 00 093 0.1 500 99 0.2 200 35.3 0.193 0.2 500 100 b. Using 100 ml isobutanol-benzene and 25 ml molybdate II 0.1 500 83 0.012 0.2 500 72 0.022 RESULTS In Table II are listed the nitrate and phosphate values obtained from Little Sodus Bay on the three sampling dates. The majority of the samples were obtained at Station #3 (See Figure 1, Page 4), and included from three depths in the water column. The second sampling period varied somewhat in that an additional sample was obtained in shallower water, Station #2, of about 5.5.meter depth. This sample was obtained to check horizontal nutrient gradients within the area. Also, several phosphate values from the taken in September. and October, 1971 were used for comparison.
TABLE II Phosphate and Nitrate Values. in Little Sodus Bay, New York During Winter Ice Cover and Early Spring, 1972 Nitrate: Station 3 Date 2/25 3/24 4/28 Station 2 3/24 Phosphate: Station 3 Date &Type 2/25 Total part.soluble Total soluble Total part. 3/24 Total part.soluble Total soluble Total part. 4/28 Total part.soluble Total soluble Total part. Station 2 3/24 Total part.soluble Total soluble Total part. Surface 1.23 ppm 2.00 1.10 1.85 ppm Surface 0.14 0.11 0.03 0.12 0.025 0.095 0.056 0.010 0.046 0.11 0.04 0.07 De.:e.ths 4 M. 5.5 M. 7 M. (Bottom) 0.90 ppm 0.86 ppm -0.85 1.08 1.08 Depths 4 M. 5.5 M. 7 M. (Bottom) 0.09 0.125 0.085 0.125 0.005 0.0 0.04 0.01 0.03 0.070 0.050 0.005 0.001 0.065 0.049 *(Nitrate values expressed as ppm N03 ; phosphate values expressed as ppm P04)
48 Sampling date FebruarY 25 The initial sampling was conducted during ice cover of about18-inch thickness. Nitrate analysis was performed the same afternoon;phosphate analysis was conducted the following week. It is generally believed that storage of samples prior to phosphate analysis may either increase the real concentration due to bacterial or enzymatic decomposition of organic phosphorus, or may decrease the concentration due to utilization by growing bacteria and plankton or absorption onto the detritus or sample bottle. The dela;y in filtration with this sample may have resulted in the similar values of soluble and soluble-particulate phosphate observed; or more likely, because of the low productivity under the ice, most of the phosphate was actually soluble rather than particulate. Nitrate concentrations show a decrease toward the bottom of the water column. This might be expected, since any surface or ground water runoff into the bay would be warmer and less dense than the water under the ice. This runoff water could easily contain nitrate compounds, as could rainwater or melted snow. In one study of the Lake Ontario watersheds (Neil, et al., 1967) it was estimated that the nitrogen yield from rural watersheds during February, March, and April constituted 58% to 69% of the annual contribution, and that the ratio of nitrogen to phosphorus was 8 to 1 for rural watersheds. This is the case here, with nitrate concentrations much higher than phosphate concentrations, most likely the result of ground and surface water runoff. Higher nutrient concentrations would be expected near the bottom due to bacterial decomposition of organic matter. However, no such increase was observed; nitrate values were fairly constant below the surface. The large amount of dissolved oxygen near the bottom (13.4 mg/l) may indicate that there is in fact no oxygen depletion due to decomposition as would be expected during winter stagnation. This high dissolved oxygen content might possibly be due to a failure to sample close enough to the substrate to record any oxygen depletion. The phosphate concentrations are almost equal at the surface and bottom of the water column. This would be expected from ground or surface water runoff and bottom bacterial decomposition contributing respectively to surface and bottom water nutrients. The 4-meter phosphate measurement is somewhat lower, possibly due to lack of nutrient input in this region. Sampling date March 25 Samples obtained at this time were taken under an ice cover of about 12 inches. An additional sample was taken. at the surface of Station 2 to determine horizontal nutrient concentrations. Nitrate analysis showed an increase in surface nitrate concentrations, as would be expected due to increasedsurface and ground water runoff. The intermediate sample obtained here (at 5 meter depth) indicates a nitrate concentration very similar to the previously reported values for the 4 meter and 7 meter samples at this station. The sample taken at Station 2 near the surface shows a value comparable' to the surface sample at Station 3. The soluble-particulate phosphate concentrations were slightly lower than previously, while the soluble phosphate value was considerably lower. This ma;y mean that a larger percentage of the phosphate is being tied up in particulate form. r,__
"'7 This is supported by the observation of more particulate matter on the filter paper from these samples. The productivity of the bay may be increasing, however slightly, as the ice cover is decreasing. Again, the surface phosphate concentrations at both Stations 2 and 3 are comparable, indicating that nutrient conditions are probably fairly uniform in this area of the bay. Sampling date April 28 This final sample period was conducted after the ice was gone and air temperatures had started to increase. The proximity of this sampling station to the ice stations is estimated at about 100 feet. The open-water station was in approximately 8 meters of water. As the nitrate concentrations indicate, the bay was experiencing spring overturn. Nitrate values are equal at 1.10 ppm as N03, which is lower than the surface values obtained on the previous two sampling dates. It is to be expected that even with further spring runoff from the surrounding area, nitrate values will monitor their use by the increasing algal population. Phosphate concentrations have dropped markedly, especially the soluble !phosphate values. This also indicates use or storage by algae. Many more organisms I were collected on the filter paper from these samples than were previously. The Isoluble phosphate values reported here can only be considered roughly since with the small amount of phosphate present, very little color development resulted (over 90% transmittance). Experimental error may account for the discrepancies observed among the samples. The data obtained from the three sampling dates when plotted (Fig. 1) follow a general nutrient relationship. Nutrients tend to accumulate during the winter due to decreased productivity and increased bacterial decomposition; early spring values decrease as the vernal maximum approaches; summer values are low unless additional nutrients are supplied. due to cultural inputs from an increased summer population; autumn nutrient values may still record moderate concentrations until the time of an autumn maximum if it occurs. A more detailed study over a longer period of time might better illustrate the seasonal nutrient distribution in Little Sodus Bay. DISCUSSION Both phosphorus and nitrogen, in their various compounds, are essential nutrients to organisms. The abundance of either of these nutrients may enhance productivity within a given body of water. The molybdate blue method of phosphate determination has been criticizeci by some (Rigler, 1968) as not representing the true orthophosphate content of the water sample. The "soluble reactive phosphate" is that phosphate in the water which is readily available to organisms and is not the same dissolved inorganic orthophosphate which is measured by standard methods. Actually, the phosphate measured exceeds that which is available by a factor anywhere from 10 to 100 (Rigler, 1968). It was determined in this study that orthophosphate values obtained by the molybdate blue method were too low for accurate readings, and that a more sensitive
-----50 Figure 1. Periodic distribution ,of nitrate and phosphate values. Nitrate Concentrations at Various Depths Little Sodus Bay St. #3 2.0 1.5 N03 (ppm) 1.0 I 7 M. I 0.5 0.15 0.10 P04 (ppm) 0.05 2/25 ,3/24 4/28 Phosphate Concentrations Throughout the Year Little Sodus Bay St. #3 (Surface values) total part.-soluble ,, I,, total ,." ... ,Isoluble ...... ". ,,,, J M AM JJ A S N Months of the Year 1972 F (Dotted lines represent expected values. September and October values were taken from previous Limnology class sampling and inserted as expected values.)
method should be employed. Strickland and Parsons (1965) make note of Stephens' (1963) method for phosphorus concentrations in the range of 0.00018 to 0.009 mg/l as P (0.00054 to 0.027 mg/l as P04). It seems obvious from this simple study that within Little Sodus Bay, phosphorus may well be the limiting nutrient. Nitrate values exceed by a factor of 10 the wintertime phosphate values, and are probably derived by rural runoff into the bay. Nitrate is more easily leached from the soil than phosphate (Ruttner, 1964), so presumably the major source of phosphates to the b8 would be from the summer influx of vacationers. It would be interesting to check nitrate and phosphate values at that time. CONCLUSIONS 1. Wintertime nitrate concentrations immediately under the ice show an increase up until the time of spring overturn. 2. Wintertime orthophosphate values are extremely low, at least as low as 0.01 ppm as P04. 3. Total soluble and particulate phosphate values increase during winter ice cover, and then decrease during the time of spring production maximum. Total phosphate concentrations never exceeded 0.14 ppm as P04 during this study. REFERENCES American Public Health Association Standard Methods for the Examination of Water and Wastewater, Thirteenth Edition. 1971. pp. 233-234, 518-522, 530-532. Neil, J. H., M. G. Johnson, and G. E. Owen. 1967. Yields and Sources of Nitrogen for Several Lake Ontario Watersheds, Proc. lOth Conf. Great Lakes Research, 1967, International Assoc. Great Lakes Research, p. 375. Rigler, F. H. 1968. Further Observations Inconsistent with the Hypothesis that the Molybdenum Blue Method Measures Orthophosphate in Lake Water. Limnol. & Oceanography, 13(1):7-13. Ruttner, F. 1964. Fundamentals of Limnology. Univ. of Toronto Press, Toronto, Canada, pp. 75, 80, 90. Strickland, J. D. H. and T. R. Parson. 1965. A Manual of Sea Water Analysis. Fisheries Research Board of Canada, Ottowa, 1964, pp. 55-58. '.
Chlorophyll and Phaeophytin Determination Of A Phytoplankton Community During and After Ice-Cover By Neil D. Tritman* ABSTRACT Changes in the quantity of chlorophyll in a community of phytoplankton at three levels in the water column were followed through three sampling dates. These dates spanned the interval just prior to the spring thaw and just after the thaw. The values obtained were then related to the phytoplankton population present at each level to discuss possible quantitative and qualitative relationships. INTRODUCTION Ice cover provides a unique set of conditions for the phytoplankton. The amount of light entering the water is at a very low level due in part to the low angle of the winter sun and also to the possibilities of ice-cover on the water surface which may be further covered by a layer of snow. All of these factors act together to significantly reduce to a minimum the amount of light entering. the water. This has a great impact on the vertical distributions of the phytoplankton present. The temperature at this time of year likewise is at a very low level ranging from zero degrees at the ice surface to four or five degrees down through the water column. It is important to note here that the layers of water receiving the most light are also the coldest layers in the water column (Wright, 1964). This also plays a key role in explaining the phytoplankton population and its chlorophyll content found at a given layer in the water column. Chlorophyll concentrations are measured spectrophotometrically. Chlorophyll (a) attains an fl,bsorption peak at 663 mp. Under natural conditions chlorophyll occurs with phaeophytin and can be converted to the latter with the introduction of acid which removes magnesium from the chlorophyll heme. Like chlorophyll, phaeophytin also attains an absorption peak at 663 mp but less strongly than an equivalent amount of chlorophyll. From this decrease in extinction when the sample is acidified the amount of chlorophyll can be calculated. Corrections for the extinction due to turbidity is measured at 750 Illfl. It is important to point out that as the phytoplankton population increases, so does the turbidity which can be seen from the results. This has an important impact on the phytoplankton connnunity because as the turbidity increases the amount of light penetration decreases. Thus we can ree how a phytoplankton population can be kept in check through natural conditions. *Submitted as partial requirement for Problems in Advanced Limnology, Bio. #298, taught by R. A. Engel. It -----_..._--=.
53 METHODS AND MATERIALS Little Sodus Bay, a body of fresh water which lies about ten miles west of Oswego at approximately 76 40 min. west longitude and 25 min. north latitude (Station #3), was the site of my sampling which tood place on three dates: February 25, 1972, March 3, 1972, and April 28, 1972. The first two dates represent an interval of ice-cover and the April sampling date was just after the spring thaw. Samples were taken with a four liter plastic Kemmerer water sampler at depths of 0, 4, and 7.5 (bottom) meters respectively. These samples were immediately transferred to plastic containers and returned to the lab where they were preserved with formalin and refrigerated to prevent any population changes. The samples were thoroughly mixed and 1500 ml. of each sample was then poured through a .45r millipore filtration system coated with MgC03. This layer of magnesium carbonate is .used to keep the suspension basic to prevent the formation of phaeophytin and also to increase the retention of particles on the filter. The filter was then removed and placed in a tissue grinding tube containing approximately 4 mI. of 90% acetone, and ground until homogenous. The suspension was then placed into a centrifuge tube along with the washings of the grinding tube and pestle and the total volume was brought up 'to ten milliliters. This mixture was then centrifuged at approximately 5000 RPM's for five minutes. The absorption of the supernatant was then measured at 663 mp and at 750 with the Bausch & Lomb Spectronic 20 using a 1 cm. light path. The readings were recorded and then the sample was acidified using 0-1 mI. of a 04N sqlution of RCI and recentrifugedo The absorption was again measured at 663 mp and at 750 mr. This value represents the absorption of the phaeophytin. The unacidified corrected extinction and the acidified corrected extinction are then computed by 3 following set of equations: uElcm. AE663 uE663 AElcm. = A E750 663 u Eu50 lightpath rcm:l 663 lightpath ( cm. ) the total pigment can be calculated by the following: 1000Pt = X-K-X vol. extract (mI.) !vol. filtrate (1) = pg.!l. whereK is the extinction coefficient (89 for chlorophyll and 56 for phaeophytin). The extinction due to chlorophyll is calculated by: = The extinction due to phaeophytin is computed: Elcm. =UE1gw. ... E lcm phae 6 ::s chI The quantities of either chlorophyll or phaeophytin are computed by the following equation: P h Elcm. or phae X 1000 vOl o extract (ml.) pg.!l.chIorpae-chI = X vol. filtrate (1.) (Method taken from Yentsch, 1965).
-The quantity of chlorophyll in case was essentially that of chlorophyll a and chlorophyll b. The population of the phytoplankton samples were assayed by the following procedure: Thirty milliliters of each preserved sample from each depth level was placed into a sixty milliliter separatory funnel. Into each funnel was added Lugol's solution in the ratio of one part Lugol's solution to one hundred parts of sample. This Lugol's solution acts to stain and facilitate sedimentation of the particulate matter. After a period of no less than 48 hours, the bottom ten milliliters was drawn off, of which one representative milliliter was taken. One drop of this one ml. aliquot was then placed on a glass slide with a cover-slip and observed under the 430X objective of a Bausch &Lomb compound microscope. Ten fields were observed and species were identified and counted. The following equation was then used to determine the total population in a 1500 ml. sample: amount of sample on slide X # of fields counted =F ; area of field # of algae counted X F = # of algae on slide; # of algae on slide x 20 x 1000 = # of algae in a 1.0 liter sample. A multiplication factor of 20 is used here since one drop on the slide is equivalent to 1/20 of a milliliter. Genera present were keyed out using Needham and Needham, 1966. TABLE 1 Absorption Readings of Processed Samples (Unacidified and Acidified). Date Depth Unacidified Absorption Acidified Absorption 2-25-72 o M. u E663 = .118; u E 750 = .011 A E663 = .286; AE750 = .188 4 M. = .178; uE750 = .122 AE663 = .217; A E750 = .164 7.5 M. uE663 = .135; uE750 = .052 A E663 = .241; A E750 = .169 3-3-72 o M. uE663 = 0097; uE750 = .026 AE663 = .137; A E750 = 0071 u uAA_ 4 M. E= .103; E -0 E= .180; E-.132; 750 - 53 663 663 750 7.5 M. = .123; = .019 E663 = .293; -.194u E663 uE 750 AAE 750 u A_ A4-28-72 o M. -1 .134E=.195; E-.205; E=750 - 09 663 663 750 -A4 M. = 0 268; uE750 -.149 = .287; E= .194 750 7.5 M. uE = .193; uE -1 AE=.223; A E =.167750 - 29 663 663 750
55 2 Absorption Readings of Processed Samples (Unacidified and Acidified) Date Depth P:t E lC!.=ch hae 2-25-72 o M. 3 0 14 JIg./l. 0007 .035 4 M. 1 064 JIg./l. .003 .019 7.5 M. 2.46 pg./l. .012 .021 -3-3-72 o M. 2.10 pg./l. .005 .023 4 M. 1.50 pg./l. 0002 .018 7.5 M. 3.06 pg./l. 0005 0036 4-28-72 o M. 2.54 pg./l. .015 .028 4 M. 3.48 JIg./l. .025 .022 7.5 M. 1.87 pg./l. .007 .018 TABLE 3 Quantities of Chlorophyll, Phaeophytin, and Enumeration of Cells Date Depth Cells/I.fchl 2-25-72 o M. 0.52 flgo/lo 4.18 pg./l. 2.1 X 105 4 M. 0.22 pgo/l. 2 026 pg./le 7.3 X 10 4 7.5 M. 0.89 pg./l. 2.51 pg./l. 5.3 X 10 5 3-3-72 o M. 0.37 pg./l. 2 075 flg!l. 6.6 X 10 4 4 M. 0.15 pg./l. 2 0 15 JIg./l. X 10 4 705 M. 0.37 pog./l. 4.30 p.g./l. 2.2 X 10 5 4-28-72 o M. 1.09 pag./l. 2.74 p.go/l. 7.3 X 10 5 4 M. 1.84 Jlg./l. 2.63 pg.!l. 2.9 X 106 7 5 M. 0.52 JIg./l. 2 0 15 pg./l. 6.8 X 104..
TABLE 4 Phytoplankton Genera Identified From Little Sodus Bay. Date 2-25-72 3-3-72 4-28-72 Depth o M. Division Bacillariophyta Navicula sp. Asterionella sp. Fragilaria sp. Tabellaria sp. Division Bacillariophyta Navicula sp. Asterionella sp. Fragilaria sp. Tabellaria sp. Stephanodiscus sp. Division Chlorophyta Chlamydomonas sp. Division Bacillariophyta Navicula sp. Asterionella sp. Cyclotella sp. Fragilaria sp. Tabellariasp. Stephanodiscus sp. Division Chlorophyta Chlamydomonas sp. 4 M. Division Bacillariophyta Navicula sp. Asterionella sp. Tabellaria sp. Stephanodiscus sp. Division Bacillariophyta Navicula sp. Cyclotella sp. Asterionella sp. Fragilaria sp. Stephanodiscus sp. Division Chlorophyta. Chlamydomonas sp. Division Bacillariophyta Navicula ap. Asterionella sp. Cyclotella. sp. Fragilaria ap. Tabellariasp. Stephanodiscus sp. Synedra.sp. Meridion sp. Division Chlorophyta sp. 7.5 M. Division Bacillariophyta Navicula sp. Asterionella sp. Fragilaria sp. Tabellaria sp. Stephanodiscus sp. Division Bacillariophyta Navicula sp. CyClotella sp. Asterionella sp. Fragilaria sp. Tabellaria sp. Stephanodiscus sp. Division Chlorophyta Chlamocdomonas sp. Division Bacillariophyta Navicula sp. Asterionella sp. Tabellaria sp. Stephanodiscus ap. Synedra sp. Meridion sp. Division Chlorophyta Chlamocdomonas sp
DISCUSSION The results on the first sampling date shows a definite vertical distribution in the population and chlorophyll content in the water column. The bottom sample reveals a greater population and chlorophyll count than either the four meter sample or the surface. This generally appears to hold true on both sampling dates during the ice cover. The retreat of the ice brings about a change in the vertical distribution of the phytoplankton and chlorophyll and seems to be greatest at the four meter level. To understand these changes it is necessary to understand the influence of ice and snow cover on the aquatic community. During the first sampling date there was an ice cover of approximately one foot with about one inch of snow covering it. On the second sampling date there was two to three inches of snow covering the ice. The effect of this blanket over the water causes a vertical migration of the phytoplankton to the near surface regions to capture a maximum of the little light that passes through the covering. This would account for a higher chlorophyll and phytoplankton count at the surface than at the four meter level (Wright, 1964). The large readings from the bottom samples are due most probably to dead phytoplankters which have settled out from the upper layers and have not as yet been ingested or decomposed. The third sampling date shows a marked increase in chlorophyll and population count. Here a shift has occurred in the maximum distribution from the surface to the four meter level. At this point there is no longer a canopy over the water and light penetration therefore has greatly increased. The living phytoplankton shifts down to a zone where the photosynthesis: light ratio is at a maximum. The increase in population can,be attributed to the warming of the waters thus becoming a compatible medium for more species of phytoplankton and phytoplankton all ready in abundance to increase further. Likewise the chlorophyll content at this time The various species found are listed in the table, most abundantly of which were the Bacillariophyceae. The main purpose of this study was to relate the total chlorophyll ,content to the community present at sampling. There have been several significant papers published concerning the relationships between biomass and chlorophyll. Chlorophyll content of phytoplankton is often used as a criterion of biomass and can be determined more accurately but the chlorophyll content in relation to other criteria is often considerably variable. It has been found (Jorgensen and Neilsen, 1965) that during the period of minimal temperature, plankton algae adapt themselves primarily by varying the concentration of pigments, photosynthetic enzymes and other enzymes. Due to this increase of the amount of cell enzymes at these low temperatures, the total organic matter per cell increases while the photosynthetic pigments remain unchanged. In regards to photosynthetic carbon production, comparisons were made between marine plankton and natural populations which-led to the development of several mathematical expressions which predicted the amount of carbon production from measurements of light and chlorophyll content within the euphotic zone (Ryther and Yentsch, 1957). The weakest aspect of this formula was the varying amount of photosynthesis per unit chlorophyll at light saturation. The maximum rate of photosynthesis per unit pigment in natural phytoplankton populations is dependent on the percentage of non-photosynthetic products (phaeophytin) which increases with depth while the capacity for light uptake decreases. The presence of the non-photosynthetic pigments accentuates low carbon fixation per unit pigment values especially near the base of the euphotic zone, in this case being between 5.75 and 6 meters (Vanderbeck and Tritman, 1972). These non-photosynthetic pigments however, cannot account for all of the decreased efficiency of pigment in the photosynthetic process. There appear to be several other degraded chlorophyll forms that might account for the decrease in the efficiency of the pigment ...:<:;:..
When a natural population initially low in phaeophytin is placed in darkness there occurs a rapid increase in the amount or percentage of phaeophytin, a value comparable to that found at the base of the euphotic zone which results in the loss in the capacity for light uptake by carbon. This is inversely true with photosynthetic pigments which decrease as a function of depth in the light limited portion of the euphotic zone (Yentsch, 1965). Thus the general picture is one of decreasing continuity in the phytoplankton photosynthetic unit with water depth which is made apparent by 1) The presence of an increasing portion of the pigment as non-photosynthetic decomposition products, and 2) Low photosynthetic efficiency. Therefore it can be seen that as the light penetration decreases logarithmically, the capacity for photosynthetic carbon production and the percentage of total pigment as chlorophyll follows this trend. It is difficult to make accurate determinations using chlorophyll as a sole determining factor. Perhaps a better approach would be to use chlorophyll measurements to confirm other methods of photosynthetic carbon production. The main problem that I encountered while doing this study was a lack of time and foresight. There are many other tests that I would like to have run, mainly to give a more complete picture of the physical and chemical data at the time of each sample such as light penetration, temperature, D.O., and cloud cover just to mention a few. Also there were a great many other research papers which I would have liked to report on concerning diurnal chlorophyll fluctuations, and the diurnal migration of the phytoplankton themselves. These two topics alone could have contributed greatly to this study and these are only two out of so many others that I encountered. LITERATURE CITED Jorgensen, E. G. and E. S. Nielsen. 1965. Adaptation in Plankton Algae. pp. 39-46. In: C. R.Goldman, ed., Primary Productivity In Aquatic Environments. Mem. 1st. Ital. Idrobiol., 18 Suppl., University of California Press, Berkeley. Needham, J. G. and P. R. Needham. 1966. A Guide To The Study of Fresh-Water Biology. Holden-Day, Inc., San Francisco. Ryther, J. H. and C. S. Yentsch. 1957. The Estimation of Phytoplankton Production In The :Ocean From Chlorophyll and Light Data. Limnol. and Oceanog. 2:281-286. Wright, R. T. 1964. D,ynamics of A Phytoplankton Community In An Ice-Covered Lake. Limnol. and Oceanog., 9:163-177. Vanderbeck, M. and N. D. Tritman. 1972. A Limnological Study of the Light and Current Parameters -of Little Sodus Bay. Unpublished. Yentsch, C. S. 1965. The Relationship Between Chlorophyll And Photosynthetic Carbon Production With Reference To The Measurement Of Decomposition Products Of Chloroplastic Pigments. pp. 325-346. In: C. R. Goldman, ed., Primary Productivity In Aquatic Environments. Mem:-Ist. Italo Iaroliol., 18 Suppl., University of California Press, Berkeley. -C .==.=
An Investigation of the Vertical Distribution of The Meiobenthos of Little Sodus Bay By Robert I. Shearer INTRODUCTION Many studies concerning the population and distribution of zooplankton throughout the water column have been carried on throughout the years. Plankton sampling methods and techniques have enabled us to obtain statistically accurate samples and correlate their numbers and distribution to various physical and chemical parameters which have also been accurately determined. It has been known for sometime that planktonic forms frequently inhabit areas of anerobic conditions. Men like Woodmansee and Grantham (1961) have discovered that frequently microcrustaceans such as Mesocyclops edax can exist in the oxygen deficient hypolimnion for great lengths of time. Often similar planktonic forms are discovered while sorting through benthic samples and passed off as being picked up as the sampling apparatus was lowered through the water column. In a study of the microscopic benthic fauna of Douglas Lake by Moore (1939), he discovered a wide variety of organisms which inhabit such anerobic environments. He used a device called an ooze sucker in his work to study this area indicated as the mud-water interface. In this study Moore found that both active and encysted species of Copepoda were buried in the substrate when examining some core samples to check for stratification. It is well established that the harpacticoid copepod Canthocamptus staphylinoides will be found encysted when subjected to prolonged periods of anerobic conditions (Deevey, 1941). This has often been the case with many of the harpacticoid copepods. Considering that many of the other forms react in some what the same manner, there obviously accumulates in the sediment a great population of inactive forms. Further investigation of work done below the mud-water interface reveals active copepod forms not generally associated with the benthic region. Studies of the stratification of these forms have been conducted by Cole (1953), Pennak (1940), and Smyly (1964). Here again there is a problem of obtaining indicative samples and incorporating them with physical and chemical information. For this reason most of the information available on stratification of meiobenthos is of the descriptive and taxonomic nature. It is the purpose of this study to develop a sampling technique which could be conveniently used from a grab-type benthos sampler. It should be regarded as merely an introduction to the study of the meiofauna and its vertical distribution in the sediments. Using the principle of the soft-mud sampler (Elgmork, 1962) and some of the techniques used by Stanczykowska (1966), a mini-core technique was developed which could be used in connection with a 6" Eckman dredge. Taxonomic identification of the organisms was intentionally kept general. I feel this technique should be further tested to confirm it as an accurate sampling device. *Submitted as partial requirement f0r Problems in Advanced Limnology, Bio. #298, taught by R. A. Engel.
60 METHODS AND MATERIALS The mini-core illustrated in Figure 2 was adapted from a 50 cc plastic disposable syringe. Both ends were sawed off leaving a hollow plastic tube with a rubber tipped plunger. The shaft of the plunger was calibrated with marks at 1 cm. intervals. The bottom of the hollow tube was used to line up the calibration marks when making the 1 cm. sections of the core. The stations referred to throughout, middle (#3) and shallow (#2), are pointed out on the map (See Figure #1, Page 4) and have been used by classes at the Rice Creek Biological Station for other limnological investigations. The depths on the day of sampling (May 5, 1972) were 9.5 m and 1.5 m respectively. One Eckman dredge was taken from each station usin: g a 6" Eckman. It was important to have as little disturbance within the dredge as possible. Special care was taken when pulling the sample through the water and into the boat. Two mini-cores were randomly inserted into the sediment of the dredge. Rubber stoppers were placed in the top and bottom of each core by hand before removing them from the dredge. After removal from the dredge the bottom stopper was replaced with a plunger and the top stopper was carefully removed. By using the calibration marks on the plunger, one centimeter thick sections of the core could be scraped into a sample jar using the flat edge of a knife. This was done for each of the cores until 6 strata were obtained. The samples were then transported to the laboratory where they were immediately processed as in the manner illustrated in Figure 1. The two methods of processing cores were an attempt to discover to what extent smaller forms passed through the #80 sieve. Retained material and one portion of the split sample were fixed in a 10% formalin solution. The incubated samples were kept in finger bowls in case significant numbers of organisms passed through the sieve. The fixed samples were then sorted under a dissecting scope at lOX magnification. DISCUSSION OF RESULTS The sampling procedure as described earlier rather well considering that it was the first attempt. Although no problems were encountered with the sorting of the samples fixed immediately, the incubated samples proved to be of little value upon examination. There appeared to be activity in the samples at various periods as indicated by apparent changes in the pattern of sediment in the fingerbowls. However, upon fixation and examination no forms could be located. Hence these samples were not completely worked over. Perhaps the magnification of lOX was not sufficient to locate the organisms responsible for the sediment rearrangement. On the results of the non-incubated samples, Tables 1 and 2 seem to show some similarity between cores from the same station. However, this is merely a superficial observation and not substantiated with any statistics. Table 3 appears to indicate that a 6 cm. core is nearly deep enough to accurately sample the meiobenthos in a silt bottom. However, the results shown on the shallow station would seem to indicate that a deeper core would be
METHODS AND MATERIALS: Figure 1. Method of Sampling Middle Station Shallow Station 1 Eckman 1 Eclonan Figure 2. Mini-core adapted for use in Eckman dredge (Approximately 3/4 scale) /\1st CorestratA S'eve I _\ retained material fixed incubated material passed 1 week fixed through incubated 1 week 12.5 inside diameter 2.6 cm. 3Area of core opening =5.3 cmVol. of each 1 cm. 3 "core strata =5.3 cmhollow tube made cm from 50 cc. disposable syringe marks indicating 1 cm. levels 7 89101112 each sample split/\1/2 1/2 /\ Core #80 1920 2'1 2"2 2'3 24 Sieve ....L 13-r15-=t17 18.J each sample split1\ 1/2 1/2 retained material fixed incubated material passed 1 week fixed through incubated 1 week
TABLE 1 Breakdown of Organisms from 2 Mini-Cores at Middle Station (Depth 9.5M) A. 1st Core / Group Strata in em. 0-1 1-2 2-3 3-4 4-5 5-6 Group Total -Group % of Total Organisms Total #/Core "0 OM til 0"0P'0 uu 28 6 4 a a a 38 39% "d til OM "d o 0 ri P< al 0 uu 12 7 0 a a a 19 19% OM OM 0riP< '&al 0 zu 5 a 1 0 a a 6 6% "dOM 0 CJ M til CJ 0 CIf P< p
'0 uu 38 1 a a a a "d tilOM "d o 0 riP< al 0 uu 1 a a a a a tilOM "d OM 0riP< p.,Q) ;j P< al 0 zu a a a a 1 a "d OM 0 CJ CJ 0 al P< ::x::u 10 1 a a a a 0 CJ al til 0 18 a a a a 1 til Q) Q) al '..c::CJ 0 tlOOMri 0 a a a 3 a 1 til Q) "d 0 1d S Q) z 1 1 3 a a a til Q) til til al tlO tlO J%:l 4 a 1 1 a a alOMP
64 TABLE 3 Vertical distribution of meiobenthos within individual layers. (Percentages of total numbers of organisms from two cores per station are in parenthesis) Middle Station (#3): Substrate type -silt and clay # Organisms/lO.6 cm3 o 20 40 60 80 100 120 (65%) 0-1 1-2 Depth 2-3in cm. layers 3-4 4-5 5-6 Shallow Station (#2): Substrate type -plant detritus and sand.like particles. # Organisms/10.6 cm3 o20 40 60 80 0-1 /(40%)1 1-2 Depth 2-3in cm. layers 3-4 4-5 5-6
advisable in the detritus and larger sand particle bottom types. Table 2(B) shows that the increase shown in Table 3 from 3% to 11% is due to ostracods found in the 5-6 cm. strata. Their occurrence is most likely possible due to the macro-granularity of the substrate at the shallow station. In summation it is felt that the described sampling technique has definite merit when attempting to investigate the stratification of the meiobenthos in soft sediments. Further experimentation should be conducted with varying lengths and diameter cores to statistically test their efficiency in sampling the meiofauna. Gray (1971) has conducted these experiments and used the Index of Dispersion test to determine the replication necessary to establish the spatial variability of the meiofauna. REFERENCES Cole, G. A. 1953. Notes on the Vertical Distribution of Organisms in the Profundal Sediments of Douglas Lake, Michigan. Amer. Mid o Nato, 49:252-256. Deevey, E. S. 19410 Notes on the Encystment of the Harpacticoid Copepod Canthocamptus staphylinoides Pearse. Ecology, 22:197-199. Elgmork, K. 1962. A Bottom Sampler for Soft Mud. Hydrobiologia, 20:167-172. Gray, J. S. 1971. Sample Size and Sample Frequency in Relation to the Quantitative Sampling of Sand Meiofauna, p. 191-197, in Proceedings of the First International Conference on Meiofauna, Smithsonian Contributions to Zoology, Number 76, N. C. Hulings', editor. Moore, G. W. 1939. A Limnological Investigation of the Microscopic Benthic Fauna of Douglas Lake, Michigan. Ecol. Monogr., 9:537-582. Pennak, R. W. 1940. The Ecology of the Microscopic Metazoa. Ecol. Monogr. 10:540-596. Smyly, W. J. P. 19640 An Investigation of Some Benthic Entomostraca of Three Lakes in Northern Italy. Memo 1st. Italo Idrobiol. 17:33-56. "I Stanczykowska, A. 1966. Some Methodical Problems in Zoomicrobenthos Studies. Ekol o Pol., (A) 14:385-393. Woodmansee, R. A. and B. J. Grantham. 1961. Diel Vertical Migrations of Two Zooplankters in a Mississippi Lake. Ecology, 42:619-628. ........:..._._=. -.
Seasonal and Vertical Distribution of Zooplankton in Little Sodus Bay By J. George Bocsor INTRODUCTION The history of work on zooplankton communities begins essentially with the work of Birge and Juday during the later years of the 19th century. Birge (1898) obtained an extensive series of 3 meter samples over a two year period from Lake Mendota. He worked mainly with planktonic crustaceans, and noticed that the vertical distribution of these was related to seasonal thermal stratification. These organisms were relatively evenly distributed throughout the water column during the cold months and were found mainly above the thermoclines during stratification periods. Diel migration, although at first not detected, was later found by Birge to be confined to the uppermost 1 to 2 meters. Juday (1904) confirmed many of Birge's findings, concerning diel migration in 30 southeastern Wisconsin lakes. Since then a great many projects have been undertaken to study zooplankton. However, as Pennak (1957) has pointed out; for the most part these studies neglected to investigate the two most important aspects of zooplankton populations; namely 1) the structure of limnetic zooplankton communities in terms of species occurring at anyone time, and 2) the structure in terms of the relative abundances of the various species present. A few of the more recent studies directed at providing insight into these very basic problems concerning planktonic communities are discussed below. In considering these it is helpful to bear in mind the following quote from Elton (1946): "The ability of certain groups of species mostly separated by generic characters, to exist together on the same area while drawing upon a common pool of resources is one of the central unsolved problems of animal community structure and population dynamics." SOME RECENT STUDIES Pennak (1957) working on several Colorado lakes, used vertical series of samples taken at discrete depths with a plankton trap. He found that at anyone sample time these Colorado lakes contain 1 to 2 species of Copepoda; 1 to 3 species of Cladocera; and 3 to 7 species of Rotifera. The mean number of species for the 27 lakes sampled tended to increase from the spring (March to May) period, to the fall (Sept. to Nov.) period. December to February averages were slightly lower for the Copepoda and Rotataria. Pennak notes that it is rare to find two species of the same genus together, except for certain apparently cosmopolitan species like Keratella quadrata (Rotataria) and K. cochlearis. and that when these are found together one is generally much more abundant than the other. In addition there appeared to be little difference in the abundance of species between limnetic communities in tropical, temperate or subarctic regions. *Submitted as partial requirement for Problems in Advanced Limnology, Bio. #298, taught by R. A. Engel.
As Pennak describes the structure of limnetic planktonic communities, it is interesting to note that he finds the most abundant species of copepod, cladoceran, or rotifer nearly always to comprise over 50% of the entire population of that particular group when a vertical tow, or a vertical series of samples was considered. Generally he found that the most abundant rotifer accounted for 64% of all other rotifers. The second most abundant rotifer accounted for 20%, and all other species totaled 16% or more. These results will be compared to the findings in this study. Vertical migrations of zooplankton were studied by Swain, et ale (1970). A highly significant point is made by Swain, that certain oftl1e periodic pulsations in abundances at certain stations might best be explained as resulting from subsurface water currents, especially when horizontal tows were made against the currents. The same fluctuations -were also observed in other areas, to be independent of current directions. The 24 hour tows made for 1967, 1968 and 1969, all show considerable variance in density of organisms with the periods of the peaks somewhere between 2 to 4 hours, to as much as 12 hours. Most of the apparent vertical movement of the organisms occurred above the 20 meter level as shown by the relatively low and constant amplitude of densities below this stratum. Swain reported also, that the rotifers cochlearis quadrata were found in nearly equal abundances. Asplanchna sp. represented the dominant form in that section of the lake. Although the usual diel migration patterns appeared to be represented, there appeared also to be considerable vertical oscillation of the short period variety, although the amplitudes did not vary as much, as for the 12 hour periods o Culver and Brunskill (1969) noted some vertical distribution differences amongnauplii and more mature stages of copepods o Diaptomus and Daphnia appeared to be dominant at the surface at night, along with cyclopoid nauplii. The migrations were believed to be restricted to the mixolimnion of the lake -through a depth of about 16 meters from surface. Williams (1966) did an extensive study of the species composition and abundance of rotifers in major U. S. waterways, including several of the Great Lake rivers. He found that rotifers were the most numerous metazoans in the 128 stations that were sampled. Williams states that the ratio of rotifers to other metazoans was approximately 30 to 10 Each dominant genus was found to have only one dominant species at anyone time, as was reported by many of the earlier investigators. The exact degree ofddominance is not given however. The greatest numbers of rotifers were found between May and November, with many rotifers disappearing during the winter. Keratella cochlearis was found at c'ertain stations at all seasons of the year, but still reduced during the winter months. The sample stations in this study were all located in rivers rather than lakes, and the comparison with lake rotifer populations must be made with caution. For example, the common lake species of rotifer, Kellicottia longispina and Filinia longiseta were not dominant in the rivers studied. Of the five most abundant genera that Williams lists for the Niagara River, Keratella and Polyarthra are the two that correspond in relative abundance to the abundances found in this
study. For this particular river a count of 248.7 per liter for 5 genera was obtained. The St. Lawrence River at Massena, a fairly cold water river, yielded Keratella and Polyarthra as dominants but the absolute numbers for the 5 dominant genera were lower than for the Niagara River (63.9/liter). In nearly all cases Keratella or Polyarthra or both, were clearly the dominant genera. Indications are that these two genera would eventually assume dominance in Little Sodus Bay, as the waters warmed later in the summer. This will be discussed later on in this paper. METHODS AND TECHNIQUES Sampling was done at a single station (Station 3) in Little Sodus Bay, approximately 150 meters from the western shore, and about 1/4 way of the length of the bay. The depth at the station was 7 1/2 meters, and samples were taken with a 4 liter plastic Kemmerer bottle. Samples were taken at the surface; at 4 meters and at about 7 meters. The February 25 and March 24, 1972 samples were taken un-er an approximately 9 inch ice cover. The surface samples on these dates were taken just below the ice, while the ice free surface sample of April 28, 1972 was taken with the bottle just submerged. The 4 liters of water was strained through the bucket of a Wisconsin net (No. 20 mesh size). The organisms were washed from the bucket into a 20 ml vial and allowed to settle. Water was carefully decanted off, and 5% formalin was added as a preservative. In preparation for counting, the organisms were again allowed to settle for at least 24 hours, and the volume of preservative was reduced to 10 mI. The 10 ml sample was then to suspend the organisms, and a large aperature pipette was used to withdraw an aliquot of 1.0 ml. This was transferred to a SedgwickRafter cell, and allowed to settle. The entire 1.0 ml aliquot was counted and an average of 3 aliquot counts was obtained for each sample except the April 28 bottom, 4 meter and surface samples. Only 2 slides were counted for each of these samples due to the large number of organisms present. The keys of Edmundson (1966) were used for all identifications. All organisms were keyed to at least the genus level. The average number of each organism present in the three slides was rounded off and then corrected for counts per liter, and the total count per liter was obtained by cumulating these individual abundances. The per cent of the total of each species or group was then calculated and compiled in Table 1, along with the numbers per liter. Figure I, is a graphic representation of the percentage information in Table 1. J' '-"i:Y<_
--FIGURE 1 February 25,1972. March 24, 1972 April 28, 1972 20 40 60 80% 20 40 60 80 % 20 40 6080% Notholca sp. K. quadrata K. cochlearis Polyarthra sp. Kellicottia sp. Ascomorpha sp. Filinia sp. Cyclops sp. Cyclopoid copepod Nauplii Bosmina sp. Notholca sp. K. quadrata K. cochlearis Polyarthra sp. Kellicottia sp. Ascomorpha sp. Ascomorphella sp. Filinia sp. Cyclops sp. Cyclopoid copepod Nauplii Bosmina sp. Chydorus sp. Notholca sp. K. quadrata K. cochlearis Polyarthra sp. Kellicottia sp. Ascomorpha sp. Ascomorphella sp. Asplanchna sp. Cyclops sp. Cyclopoid copepod Nauplii Ostracoda (l) CJ al l--t ;j (/) Ul l--t (l) +J (l) ::8 ..:r 5 +J +J o f:Q --_
Seasonal and Vertical Distribution of Zooplankton In Little Sodus Bay Depth 2/25/72 3/24/72 4/28/72 Notho1ca sp. 50/1it. 16% 7/lit. 9% 23/1it. 11% Kerate11a quadrata 16 5 0 0 14 6 Kerate11a coch1earis 33 11 9 11 5 2 Po1yarthra sp. 97 32 8 10 100 46 Kellicottia sp. 8 3 0 0 1 1 OJ Ascomorpha sp. 7 2 11 13 0 0 () til trl Ascomorphe11a sp. Asp1anchna sp. 0 0 0 0 0 0 0 0 0 0 0 0 ;::l (/) Filinia sp. 2 1 0 0 1 1 Cyc1ops.sp. 16 5 28 34* 10 5* Cyc1opoid copepod 38 13 17 21 10 5 Nauplii 32 11 2 2 53 24 Ostracoda 0 0 0 0 0 0 Bosmina sp. 2 1 0 0 1 1 N = 301/lito N = 82/lit. N = 218/lito Notho1ca sp. 40/1it. 17% 13/lit. 10% 46/lit. 13% Keratella quadrata 13 5 11 8 85 23 Kerate11a coch1earis 29 12 8 6 4 1 Po1ya,rthra sp. 5Q 21 29 21 113 31 Ke1licottia sp. 8 3 3 2 10 3 Ul Ascomorpha sp. 13 5 9 7 1 1 OJ +' OJ Ascomorphe11a sp. Asp1anchna sp. 3 0 1 0 0 0 0 0 0 0 0 0 ...::t Filinia sp Cyclops sp. 0 19 0 8 0 17 0 13 3 23 1 6 Cyc1opoid copepod 19 8 26 19 16 4 Nauplii 48 20 16 12 58 16 Ostracoda 0 0 0 0 0 0 Bosmina sp. 0 0 2 1 3 1 Chydorus sp. 0 0 2 1 0 0 N = 242/lito N = 136/lit. .N = 362/lit. Notho1ca sp. 16/1ito 10% 10/lito 10% 29/lit. 9% Kerate11a quadrata 25 16 28 29 183 55 Kerate11a coch1earis 30 19 4 5 0 0 Polyarthra sp. 38 25 18 19 48 15 Ke11icottia sp. 10 6 9 9 3 1 Ascomorpha sp. 0 0 7 7 1 1 S 0 +' +' 0 f:Q Ascomorphel1a sp. Asplanchna sp. Filinia sp. Cyclops sp. 3 1 0 6 2 1 0 4 0 0 0 4 0 0 0 5 0 0 0 3 0 0 0 1 Cyc1opoid copepod 7 5 8 8 8 2 Nauplii Ostracoda 17 2 11 1 8 0 8 0 56 0 17 0 Bosmina sp. 0 0 0 0 0 0 N = 155/lit. N = 96/lit. N = 331/lit o *Several females with eggs -. -..' .. .... -,
RESULTS AND DISCUSSION With regard to the vertical distribution obtained on anyone date, there appears to be little significant difference between the 3 levels. Keratella sp. (probably K. quadrata) does however appear to become more abundant toward the bottom. On February 25, the percentages from surface to bottom are 5%, 5% and 16%. For March 24, these are 0%, 8% and 29%. For April 28, they are 6%, 23% and 55%. Calculated numbers per liter of this species of rotifer, for these dates also shows an increase in absolute numbers from surface to bottom. It is perhaps significant that the other species of the same genus cochlearis) appears to show a negative correlation from surface to bottom, with the abundance of K. quadrata. This would seem to support the finding of Pennak (1957), that it is unusual to find two species of the same genus coexisting, and that when one does find this, one species is clearly dominant over the other. While the degree of dominance is not as great here, generally less than 50%, it would seem that the more abundant one species becomes, the less abundant the other. Swain, et al. (1970) has found that these two species do coexist in nearly equal abundances, but it is difficult to compare such findings based on different lakes and different sample methods, and different times ofthe year. Pennak does in fact consider these two species cosmopolitan in their distribution. On the reports of Birge (1898), there would seem to be little justification for expecting great vertical distribution differences on the first two sample dates, since the entire water column should have been at this time of the year. Birge reported an even distribution of planktonic crustaceans during the cold months. The present study does not provide evidence for any diel migration since the samples were taken during the same time of day under relatively similar light conditions, at least for the first two sample dates. Another dominant rotifer, Polyarthra, also seems to be evenly distributed with some noticeable increase in numbers at the 4 meter and surface levels on April 28, after ice-out. None of the samples in this study indicate the relative abundances of the dominant species which Pennak describes. For none of the samples obtained here does the abundance of the dominant rotifer exceed 50% of all other rotifers as Pennak has suggested. Neither are the rotifers present in the abundances of 30 to 1; rotifers to other metazoans (Williams, 1966). Examination of abundances of rotifers in the April 28 sample, reveals that the two species quadrata and Polyarthra sp. are nearly equally represented when the entire water column is considered, and that taken together they do exceed .50% of all other rotifers. This change from the ice cover data suggests that population composition may be about to change considerably as the water begins to stratify and the incident light energy increases. The abundances of the cyclopoids and nauplii are more difficult to interpret because of the smaller numbers present. February 25 data shows that the nauplii predominate numerically. On March 24, the situation for the surface and 4 meter sample at least seems to be reversed, while on April 28 the nauplii again predominate. -------,.' "'OS..., j r 6 i _.a
-The presence of females with eggs in the surface sample of March 24 and April 28, may have a direct bearing on the relative and absolute increase of nauplii on the April 28 date. Two significant trends can be discerned when considering the relative abundances of the various groups (especially the rotifers). First, there is a discernable difference in distribution of species for the entire water column between the two ice cover samples and the ice-out samples in April. Second, there is a definite reduction in overall population densities for the March 24 samples. Less definite is an overall increase in the densities for the April 28 samples. Concerning the first difference listed, the abundance of most of the rotifers especially, are generally of the same order of magnitude (certainly no one species is dominant to the extent that Pennak and Williams reported), for both February 25, and March 24 sets of samples. However with the April 28 sample, some trends toward dominance, especially of quadrata and Polyarthra are quite definite. Rather than a fairly uniform distribution of most species, and a relatively low density of organisms, by April 28, the abundances seem to be readjusting to a situation where a few species are very abundant (dominant) while most species are increasingly rare. Concurrently, the total numbers per liter increase also. The other anomaly is the considerable reduction in density for the three March 24 samples. Undoubtedly some population changes are occurring, especially among the planktonic crustaceans, but the changes in relative abundances of the rotifers are not too marked or consistent. When the entire water columns for both dates (Feb. 25 and March 24) are considered, the difference seems to be mainly a reduction in density for the second date. Perhaps the most plausible account for this would be the influence of SUb-surface currents (Swain, et al., 1970), which may have been present at the station location at that particular time. Such currents could conceivably diminish non-selectively the density of the zooplankton populations, thus accounting for a decrease in numbers but no significant change in the per cent representation of each species. It should also be noted, that the overall number of species or groups remains fairly constant throughout the sample period, and it can be assumed that these species constitute the usual winter fauna of the bay. Undoubtedly as Williams (1966) has observed, other species will take their places at other times of the year. CONCLUSIONS Pennak (1957), discusses two concepts of niche: "niche" as habitat locations and "niche" as differences in food requirements. I would like to consider these distinctions and especially how they could be used to explain the first difference between the two winter samples and the April 28 sample as described above. In the sense of the term "niche" which refers to the heterogeneity of the substrate which makes available an assortment of habitat to a diversity of zooplankters, any water environment is relatively homogeneous. Except for temperature stratifications and differences in oxygen content, the limnetic environment does not provide a heterogeneous or widely diversified set of conditions for which the organisms could develop specific adaptations. It is essentially a "buffered" environment in this sense. r fit ------------
73 The alternative concept of "niche" refers to the energy or food requirements of various organisms. It would seem that if two taxonomically different organisms coexist, that they must ipso facto have different niche requirements, whether or not these differences are readily apparent to the anatomist or physiologist. Invariably, the process of evolutionary adaptation which these organisms have undergone, and which resulted in a characteristic phenotype, must have involved the integration of some very "minute" differences in the supplies of food energy, the end result being a particular species, distinct from all others, and specifically adapted to that energy (food) source under that particular set of conditions. It would seem, furthermore, that in an environment eharacterized by relatively low amplitude fluctuations in some physical factors, and a relatively homogeneous nature with regard to other physical factors; that the nature and diversity of the available food energy would be a determining factor in the number of species such an environment could support. This diversity in available food energy need be no more complex a phenomenon, than say, a range in size of organic particles which zooplankters would eat. Conceivably, such a diversity in food particle size, to use an example, could supply the "niches" for several species of organisms, each specifically adapted to utilize particles of a certain size range most efficiently. The limnetic zooplankton community is indeed a remarkably simple one in terms of structure and in terms of the number of species it supports. The number appears to be about 10 to 12 genera at anyone time for the community studied here. This fact seems to be in harmony with the postulate that limnetic communities are food "niche" limited. During the colder months (February and March) especially with ice cover, there appears to be a relatively stable, evenly distributed population of about 10 genera, with no one species especially dominant over the others. If we assume that conditions for population increases are at their low point with regard to temperature and availability of food, then the situation found here is readily accounted for. Conditions simply are not such that any "blooms", whether for one species or more, can occur. By April, the situation begins to change. Increasing temperatures, increased oxygen, and mixing of nutrients by winds on the ice free bay, along with increased sunlight, make more food energy available, and those organisms present, which happen to be most efficient at utilizing .the food energy available will tend to increase in numbers, (e.g. quadrata, and Polyarthra). These become dominant, presumably at the expense of the potential for increase in other species. When conditions are such that more biomass can be supported by a given unit of environment at a particular time, it seems that living things will find some way to exploit the possibility. On .the evolutionary time scale this has resulted in the development of new species, while on the scale of seasonal changes, the response is in terms of increases in numbers of certain segments of the existing community. While this does not solve Elton's problem, this may be the general direction that offers the best hope of an eventual answer ... '-.-,\19 2..
REFERENCES Birge, E. A. 1898. Plankton studies on Lake Mendota. II. The crustacea of the plankton from July 1894, to December 1896. In: Frey, D. S., ed. Limnology in North America, University of Wiscon;in Press, Madison, Wisconsin. pp. 16-21. Culver, D. A. and G. J. Brunskill. 1969. Fayetteville Green Lake, N. Y. V. Studies of 10 production and Zooplankton in a Meromictic Marl Lake. Limnology and Oceanography, 4(6):862. Edmondson, W o To, ed. 1966. Freshwater Biology. John Wiley and Sons, Inc. N. Y. 1248 pp. Elton, C. 1946. Competition and structure of ecological communities. Journal of Animal Ecology, 15:54-68. Juday, C. 1904. The diurnal movement of plankton Crustacea. In: Frey, D. S., ed. Limnology in North America, University of Wisconsin Press, Madison, Wisconsin. pp. 16-21. Pennak, R. W. 1957. Species composition of limnetic zooplankton communities. Limnology and Oceanography, 2(3):222-232. Swain, W. R.; R. W. Magnuson; J. D. Johnson; T. A o Olson, and T. O. Odlaug o 1970. Vertical migration of zooplankton in western Lake Superior. Proc. 13th Conference on Great Lakes Research. International Association of Great Lakes Research. 619-639. Williams, Louis S. 1966. Dominant planktonic rotifers of major waterways of the U. S. Limnology and Oceanography, 11(1):83-91. I $!. ;..-.... ,,_t ----._------:lIr .....
GENERAL NOTES A Simple and Efficient Benthos Sorting Dish By Robert I. Shearer In.the process of sorting meiobenthos samples under a dissecting microscope it was discovered a great deal of time was wasted covering the same area when an ordinary petri dish was used as a sorting dish. At first the problem was solved by inverting a smaller petri dish inside and adding the sample. This later proved inadequate as the sample would leak into the center of the smaller dish. With a little fabrication. this sorting dish and microscope stage resulted and has proved to be extremely beneficial when sorting or counting organisms in a sample where magnification from a dissecting scope is adequate. It is a very inexpensive and easily constructed item and has proven invaluable in our laboratory teaching and individual research. The dish (Figure 1) is constructed by cementing the bottom of a 60 x 15 mm petri dish inside the bottom of a 100 x 15 mm petri dish using an epoxy cement. This leaves a circular trough approximately 2 cm. wide. A reference mark may be placed on the bottom of dish with a felt marking pen so that the user can determine when one sweep of the dish has been completed. An adapter (See Figure 2) to hold the dish in place on the microscope staging can be easily constructed of 1/4" plexiglassand epoxy cement. This adapter allows the user to rotate the dish with one finger and leave the other hand free to use a probe or forceps in removing the organisms. Various size petri dishes could be used according to magnification requirements or personal preference. Using the described dishes we are able to achieve a lOX magnification of the entire trough diameter with a Bausch &Lomb Model BFB-l Stereo Loom microscope with lOX eyepiece. Depending on the personal preference one can also cement a plastic retainer across the trough so that organisms will not migrate in the dish as it is rotated. r I Figure 1 Figure 2 Sorting Dish Microscope Stage Adapter 88 f'e.. ,at., 'F -_. _... _SA ....,. -c' -.' .-_--:.,.=-----
IV GENERAL NOTES (continued) A Modified K. B. Type Corer By J. Eddy Demers The need for an inexpensive, but effective core sampler produced this prototype. Generally copied from the better known but considerably more expensiveK. B. Corer, this model is constructed of materials easily obtained from any hardware store, but compared favorably with the K-B Corer in actual field tests. The specific dimensions can be worked out during the construction and modified to suit needs. The body of the corer (See Figure 1) is composed of two (2) 5 1/2" cast iron flanges with 2 1/2" threaded openings separated by lengths of 1/4" threaded rod inside, 8" long, 1/2" galvanized pipe acting as tubular spacers. A 2' long 2 1/2" OD galvanized pipe protrudes from the bottom with an 8" length of the same diameter pipe extending from the top. A combination of a short length of 2 1/2" OD pipe with a reducer allows for the use of a smaller diameter 1 1/2"OD pipe (See Figure 2). The tripping mechanism (See Figure 3) is comprised of flat metal with an angled piece as the spring loaded pivot release for the 'plunger'. The messenger slides down the attached line striking the angled portion of the tripping mechanism releasing the plunger. This drops to cover the opening in the flange below which is covered by rubber gasket material. 'Suction' holds the sediment in the core until the suction is broken by raising the plunger. Figure 1 Figure-3 (Drawings not to scale.) Figure 2 ._---_.,.---._._.... _..... .--;;:';';;'iii? -soCd0 CJ o