Blue-Green Algal Mats from Acidified Adirondack Lakes: Mat Structure and Ph Response of Algal Isolates Maureen Ann Leupold the College at Brockport

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Biology Master’s Theses Department of Biology

10-1983 Blue-Green Algal Mats from Acidified Adirondack Lakes: Mat Structure and pH Response of Algal Isolates Maureen Ann Leupold The College at Brockport

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Repository Citation Leupold, Maureen Ann, "Blue-Green Algal Mats from Acidified Adirondack Lakes: Mat Structure and pH Response of Algal Isolates" (1983). Biology Master’s Theses. 33. https://digitalcommons.brockport.edu/bio_theses/33

This Thesis is brought to you for free and open access by the Department of Biology at Digital Commons @Brockport. It has been accepted for inclusion in Biology Master’s Theses by an authorized administrator of Digital Commons @Brockport. For more information, please contact [email protected]. BLUE-GREEN ALGAL MATS FROM ACIDIFIED ADIRONDACK SLAKE : MAT STRUCTURE AND pH RESPONSE OF ALGAL ISOLATES

A Thesis Presented to the Faculty of the Department of Biological Sciences of the State University of New York College at Brockport in Partial Fulfillment for the Degree of Master of Science

Maureen Ann Leupold October 1983 ..''. ...

i· THESIS DEFENSE FOR ..

.Master's·Degree Candidate ...... :=· . APPROVED .. NOT APPROVED llASTER' S DEGREE ADVISORY COMMITl'EE ... I

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. ,/ ali �·{: ..· · Od: r1 19t3 Committee,_ Member ...... Date... •f'•• I.':.•.:., .:"'°"')'!'"~ .. . - ...... , . - .:.:.�_,· � -· ...... - ~:' .:-.- . ·.·· ,,

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...... ··.· ·; ...... , . .,.. -. Acknowledgements

I thank Dr.J.C.Makarewicz for his support, guidance and encourage�ent during all phases of this project,- both in the field and in· the laboratory. ·ram grateful for the ti1Ile he has invested in my education. Sp�ctal thanks to Dr.C.Barr· for his techn'ical help, equi'pm-ent loans and constant enthusiasum. I thank nr.R;·J .M cLean for his advice, assistance in ·algal identificatiorr·and especially the pep talks. I appreciate the additional assistance that the Biology Department provided in the course of my studies at Brockport.

Many fellow students and friends helped with the field work. Pam Green, Ted Lewis, Brian Kent, Julie Warner and Dorothy McKellar all deserve specia1 thanks for �heir strong backs and sure feet. The laboratory assistance provided by Pam Green was greatly appreciated.

Financial assistance was provided by the Department of Biological Sciences and the Research Foundation of SONY. I thank Dr.J.C.Makarewicz, Catharine Owen and Or.R.Thompson for this assistance. I also thank Sigma Xi for a Grant-in Aid of Research awarded to this study.

This work could not have been accomplished without the loving support and encouragement my husband Steve. I am forever grateful for his patience, help and love.

; ; Table of Contents

Introduction------1 Methods------4 Fieldwork------4 Algae Culture Isolation------5

w Ecophene Experiment------6 Dilution Experiments------7 Growth Curves------7 Nutrient Addition------8 Titration Experiment------8 Results------9 Algal Mat Development------9

< Ecophene Experiment------10 Dilution ~xperiments------11 Growth Curves------11 Nutrient Addition------12 Titration Experiments------12 Discussion------14 Taxonomy------14 Algal Mat Development------16 Water Chemistry------21 Literature Cited------24

iii List of Tables

Table l. Location, elevation and surface area of lakes sampled in the Adirondack Mountains of New York during the Summer of 1982.

,, Table 2. Temperature, pH and alkalinity of Adirondack lakes sampled.

Table 3. Partial list of algal genera identified from preserved benthic samples.

Table 4. Dominant blue-green algae in mat systems in acidified lakes.

iv List of Illustrations

Figure 1. Growth versus pH of Schizothrix calcicola isolates from Limekiln Lake, Falls Pond, Big Moose Lake and Wolf Lake.

Figure 2. Results of the Newman - Keules multiple range test.

Figure 3. Growth of Schizothrix calcicola (Limekiln Lake) in reduced strength unbuffered CFig.3a) and buffered (Fig.3b) medium.

Figure 4. Growth curves of Schizothrix calcicola in pH 6.0 and 7.0 (Fig.4a) and pH 4.0 and s.O (Fig.4b) buffered media.

Figures. Growth of Schizothrix calcicola (Limekiln Lake) in half strength buffered (pH 4.0) media with and without added nutrients.

Figure 6. Percent suspended algae versus decreasing pH.

17 ABSTRACT

Seven acidified lakes in the Adirondack mountains of New York, USA were sampled for benthic alga� during the summer of 1982. Benthic cyanophyte mats, dominated by Schizothrix spp. were found in three of the seven lakes sampled (Big ' Moose, pH 4.00-4.40; Limekiln, pH 4.60-5.30; Wolf, pH '3.45-3.70). The blue-green algal mats found -were structurally similar to living str'omatolfte analogs found in other extreme environments� Uhder controll�d �aboratory conditions, unialgal isolates of Schizothrix calcicola (Ag.) Gorn., grew best at or near neutrality but could survive and grow slowly_at low pH ( 4.0, 5.0). Increased nutrient levels appeared to have little affect on growth or I � survival in buffered low pH (4.0) media.� Cultures of �.calcicola were able to raise the pH of unbuffered media three pH units in less than 72 hours. Clumping and aggregation of filaments was enhanced by lowering the pH (to pH 3.5 in 5.5 hours) of actively growing cultures.

vi INTRODUCTION

Increased acidity and the concurrent changes in nutrient and metal concentrations caused by acid precipitation affect all trophic levels in sensitive aquatic ecosystems. Acidified lakes have impoverished zooplankton assemblages.~ (Almer .e..t .a.J.. 1974, Hendrey and Wright 1976, Roff and Kwiathowski 1977, Raddum .e..t .a.J.. 1980, Yan and Struss 1980, Confer .e..t .a.J.. 1983), often dominated by acid tolerant species Ce.g. Bosmina, Polyothera, Diaptomus (Confer .e..t .a.J.. 1983)1. Similarly, phytoplankton species diversity declines with decreasing pH (Almer .e..t .a.J.. 1974, Kwiathowski and Roff 1976, Hendrey and Wright 1976, Yan 1979). In some acidified lakes, aquatic macrophytes are being replaced by mosses (Almer .e..t .a.J.. 1974, Hultberg and Gran 1976, Hendrey and Vertucci 1980) or are being covered by abundant growths of periphytic algae, often dominated by diatoms and filamentous green algae (Lazarek 1982b, Muller 1980). Not only are the benthic fauna reduced or eliminated by the decreased pH C< 6.0) (Okland and Okland 1980) and increased metal concentrations CRaddum 1980) but also by the altered conditions of the lake bottom sediments (Almer .e..t .a.J.. 1978). For example, increased rates of sedimentation of organic debris which is evidence of reduced decomposer activity (Hendrey .e..t .al. 1976, Traaen 1980), may also exclude certain b enthic species (Almer� al. 1978). In general a shift in species composition and 2

a decline in species diversity occurs. Although many organisms, such as fish (Beamish~ .a.J.. 1975, Schofield 1976), are eliminated, acidified lakes are often dominated by the few species which are able to exploit the changed conditions.

•The development of benthic algal mats in lakes acidified by acid precipitation is also a recent phenomenon. These dense, felt-like algal mats which blanket the bottoms of some acidified lakes, are composed primarily of tsmall filamentous blue-green algae (Oscillatoriaceae). Although low diversity cyanophyte mats are known to occur in many extreme environments such as Antarctica lakes, thermal pools and alkaline lakes (Parker .e..t .al. 1981), the mats described in Lake Colden, -New York (Hendrey and Vertucci 1980) and Lake Gardsjon, Sweden (Lazarek 1980) are the first reports from environments below pH five. Blue-green algae have historically been thought to be excluded from acid conditions (Brock 1973). Thus it is surprising to find them as the dominant benthic organisms in acidified lakes.

In Lake G!rdsjon, algal primary productivity of the mat was

-2 -1 32.8 +/- 12.9 mg Cm ~ay~Lazarek 1982). The contribution of blue-green algal mat primary productivity to the total annual primary productivity of acidified lakes has not been estimated, but may be relatively high in these impoverished 3 lakes CLazarek 1983).

The objectives of this study were to document the occurence of cyanophyte mats in Adirondack Mountain lakes, identify and isolate. the maj.or mat_ .forming species. into unialgal cultures ap9 peter�ine tn� efte9ts of pp 9n ,9+9�tp 9f the isolated sp;cie.P-. unger pp�trolled i�boiatory conqttion�, We Jest bere j:jl� hyp.9Jl}esis that the bl��-g_;,eep aJ.gae ·� oj)served. jp Penthic mats in acidif,ied 19ke� are a,cj.dpphJ.ic ecophenes. METHODS

Fieldwork

Seven lakes were chosen based on previously reported pH values (Pfeiffer and Festa 1980) and observations of benthic algal mat development (Lee, personal communication, Vertucci, personal communication). Wolf Lake, Falls Pond and Cellar Pond are small high elevation lakes, reached only by hiking trails (Table 1 >. Equipment, including a small inflatable boat, was backpacked into these areas. Big Moose Lake, Dart Lake, Fourth Lake and Limekiln Lake are larger, lower elevation lakes (Table 1) near accessable roadways.

In all the lakes, surface and bottom water samples were obtained with a Van Dorn water sampler. Within eight hours after collection, alkalinity was analysed by potentiometric titration (American Public Health Association 1975) in June and July, and by the Gran titration procedure (Talling 1973) in August.

Temperatures were measured with a thermistor thermometer. In June and July pH readings were determined from collected water samples with a Corning pH meter equiped with a combination electrode. In August pH was obtained .in .ait.Y.

4 5

Benthic algae samples colle~ted with an Ekman Grab sampler were preserved with Acid Lu~ol's solution. Live materia~ for culturing purposes w~s stored in translucent plastic bottles for return to the laboratory. The Drouet (1968) class,ification and nomenclature system. w,as employed for all " Oscillatoriaceae identification.

Algal Culture Isolation

Algal enrichment cultures were started using Guillards' Woods Hole MBL medium (Nichols 1973). Schizothrix c~lcicola (Ag.) Gorn. was isolated from four lakes into unialgal cultures following the methods of Hoshaw and Rosowski (1973). Attempts tp obtain axenic cultures py centrifugation, ultrasound treatment, antibiotics and surfactants were unsucessful (Hoshaw and Rosowski 1973}. The presence of bacteria in the unialgal cultures was continuosly monitored by inoculating Difeo Nutrient Broth with culture material, streaking plates of Guillards' medium solidifed w~th 1.3% agar and subsequent microscopic examination. Throu~h successive transfers from liquid to solid medium bacterial contai;nination was reduced but not eliminated in the isolates. Aseptic technique was used throughout to minimize bacterial contamination.

Stock cultures of the ~.calcicola isolates were kept in a growth chamber at 20°C with a light ,cycle of 16 hours 6

light, 8 hours dark Cca.3000 lux) under cool white fluorescent tubes. Guillards' medium was modified for all

experimental work and stock cultures by eliminating Na 2 Si04 enabling better control of pH after autoclaving. Stocks were routinely transfered each week. All experiments were begun with seven day old cultures in Pyrex erlenmyer flasks. Cell counts were.with a hemacyto~eter C Improved Neubauer Ruling) by the method of Burnham .et .a.l.El973).

Ecophene Experiment

~.calcicola isolates from Limekiln Lake, Falls Pond, Big Moose Lake and Wolf Lake were grown in a pH range of 4.0 to 7.0. Experimental cultures (initial density~ 5.0 x it cells per ml) contained modified Guillards' medium buffered with 0.2% cyclo acid Ccyclopentanetetracarboxylic acid). pH was adjusted (4.0-7.0) in 0.5 increments using NaOH prior to autoclaving. Each pH level was run in triplicate. Experimental conditions included constant light Cca.3250 lux under cool white fluorescent tube.p) and t!=mperature (20° C) with shaking at 100· RPM. Flasks were randomized daily to insure no positioning effects. At the end of seven days pH was measured and dry weight measur.ements of growth were obtained by ~he membrane filtrati-0n.method of Sorokin (19731. Control filters Cn=lO), rinsed.with deionized~distille'd water, were proc~ssed in the same manner as experi~ental filters Cgrowth~zero). 7

Dilution Experiments

Unbuffered modified Guillards' medium was prepared at 0.10, 0.25, 0.50 and 1.00 strength and adjusted to pH 4.0 with

H2 S04. Limekiln Lake a.calcicola were centrifuged and washe'd two times with 0.1 O ·strength medium. Each nutrient level was run in quadruplicate, starting with 3.4 x 104 t cells per ml. Growth condi·tions duplicated the ecophene experiment except the flasks were not shaken. At tne end of two weeks pH was measured and cell counts were made to determine growth.

The second dilution experiment differed in that the medium was buffered with 0.2% cyclo acid and dilution strengths were 0.125, 0.250, 0.375 and 0.500. Growth was determined by cell counts on day ro.

Growth Curves

Limekiln Lake isolates of ~.calcicola were grown in o.s strength modified Guillards' medium with a pH range of 4.0

to 7.0 buffered with 0.2 % cyclo acid C adju~ted with Tris base to the desired pH level). Washed cells of the Limekiln Lake isolate were inoculated into 30 ml of medium in 50 ml flasks giving an initial cell density of 4.3 x I04 cells per ml. Growth conditions duplicated the ecopherte experiment. For 14 days, triplicate flasks from each pH 8 level were harvested daily for cell counts of suspended and total algae and pH measuremen£s.

Nutrient Addition

Addi trohai. �nutrients, equal1ng the original amount contained in 0.50 strength medium were added to 7 day old cultures of Limekiln�ake�.calcicola. Experimental conditions duplicated the growth curve experiment. On days 7 and 14 cell counts from curtuies with added nutrients and from control cultures with added deionized-distilled water were made.

Titration Experiment

500 ml of 0.50 strength unbuffered modified Guillards' medium in a liter flask was inoculated with Limekiln Lake • • 5 B.calcicola isolates to a starting cell density of 1.5 x 10 cells per ml. The culture was shaken at ca. 50 RPM in a growth chamber under constant light (3150 lux) and ° temperature C20 C). pH of the growing culture was continuously monitored with a Chemtrix pH -meter and a Beckman recorder. Starting at the peak of population growth, density was monitered (by cell counts of suspended algae) as the pH was lowered with a pH Controller connected to an automatic injection syringe containing 0.02 N H 2 S04 • The pH was lowered to 3.5 over s.s hours. RESULTS

Algal Mat Development

Wol� L�ke contains a b�nthic algal mat co�posed primarily of the blue-green alga Schizothrix Friesii CAgardhJ I .) uomont,. .. (Oscillatoriaceae). The mat is dark green,

underlying a�d occasionally growing over.l submerged ,J macroph�tes. Schizothrix Friesii filaments are 3 to 4 ilm in diameter with cell lengths of 5 to 9 ilm and secrete a distinct sheath. The mat is laminated with live filaments on top of discarded sheath material and dead filaments. Diatoms are frequently dispersed within the mat.

The algal mat in Limekiln Lake is extensive in the littoral zone, covering the sediments, logs, rocks and submerged macrophytes. The growth ranges in color from olive-green:., - to greyish tan. The matrix of the mat is formed by' a small \., blue-green alga, Schizothrix calcicola CAgardh.) Gomont, 1.5 to 2.0 ilm in diameter, which secretes a gelatinous sheath. Other cyanophytes, including schizothrix Friesii, Merismodedia sp., Hapalosiphon sp. and Chrococcus sp., are dispersed throughout the densely entangled filaments of Schizothrix calcicola. Diatoms, desmids and the red alga Batrachospermurn sp. are also associated with the mat •

Big Moose Lake contains areas of mat development similar to

9 10

Limekiln Lake but not as extensive. Dense growths of the green alga Mougeotia sp. occurs as periphyton and ( metaphyton. Batrachosperrnurn sp. is also frequently encountered as periphyton.

No cyanophyte mat development was observed in Cellar Pond, Dart Lake, Falls Pond or Fourth Lake, yet the major mat forming Schizothrix species were present in all lake benthos samples. Temperature, pH, and alkalinity of the seven lakes is given in table 2. Of the seven lakes, only Falls Pond had received state sponsered lime applications in 1975 and 1979: private landowner organizations have limed the north bay of Big Moose Lake in the past (Pfeiffer personnel communication, see appendix II). Table 3 is a partial list of the algal genera collected from all the lakes' benthic samples.

1 Unialgal cultures of Schizothrix calcicola were isolated from Big Moose Lake, Limekiln Lake, Falls Pond and Wolf Lake. Schizothrix Friesii from Wolf Lake would not grow in defined media under laboratory conditions (see appendix III).

Ecophene Experiment

All isolates grew best at or near neutral pH (6.5 or 7.0) Cfig.1). A Newman - Keules multiple range test (p = .05) 11

Czar 1974) indicated that generai1y below pH 6.5, no significant difference in abundapce occurred between each pH range for each isolate (fig.2).

Dilution Experiments

Static cultures of Limekiln Lake Schizothrix calcicola in unbuffered media (initial pH 4.00) grew equally well in full and half strength media Cfig.3a). Mean pH Cn=4) was ~-~O in palf strength and 7.84 in futl qtren~th experimental cultures after two week incubation p~riods~ No live algae were found in the 0.10 strength medium C pH after two weeks= 4.05). 15.7% of the inital cell density C 5.32 x ~O 3 cells per ml) was present in the 0.25 strength medium after 2 weeks' incubation C final pH= 3.BO)Cfig 3a). Static cultures, incubated for 10 days in buffered

(pH 4.0), reduced strength media C0.500, 0.375, 0.250, 0.125 >, never reached the initial cell density Cfig.3b). However, cel.l survival qccured at all pH levels ,Cfig.3b).

Growth Curves

Mean daily cell counts of Limekiln Lak~ .Schizothrix calcicola. c,ultures C n=3 > buffered in one u~it increments from ~H 4.0 to 7.0 are given in figure 4. The gr?wth curv.es at pH 6.0 and pH 7.0 are ~y~ical sigmoid curves, displaying exponential growth from .days four to seven 12

Cfig.4a). A-decrease in cell 1 density occurred initially at pH 4.0 by day two followeg by a cyclic but increasing growth pat�ern, At pH 5.0, a slight ipcrease in cell density Dpcurred by d ay two followed by a decline in cell density by day four (fig.4b). Gell density increased in a cyclic pattern f rom day four to fourteen.

Nut�ient Addition

Adding additionial nu�rients to, seven day old cultures caused no significant difference in growth or cell s�ryival between nutrient levels (fig 5). Cell density remained nearly constant in all nutrient levels over the two week incubation period.

Titration Experiment

Limekiln Lake Schizothrix calcicola isolates grown in unbuffered medium initially at pH 5.00 changed the pH to over 8.00 in less than 72 hours. By day three the algae had attached to the flask bottom and sides, forming a green film. By day five the pH had reached 10.20 and dense tufts of attached algae had formed on the bottom. When the pH had reached 10.45 on day six, the solution became greener as the attached algae proceeded to disperse into the solution. On day eight no attached algae were visable and the solution (pH = 10.30) was bright green. As the pH of 13

the solution was lowere~ with B2 S04 , the suspended algae gradually flocculated and settled out of solution. Figure 6 is a graph of the percent of suspended algae C 100% = abundance of suspended cells per ml before titration) versus decreasing pH. Less than 20%.~f the algae was still in suspension ~t pH 4.00. R~attac~ment to the flask bottom

occured two hours after pH 4.00 had been reached.I Sixteen

hours after pH 4.00 had been ~eachedV the• pH had d~opped to

3.62 (no additiq~al ~ SO wps add~d) apd tpe,plgae had formed a loose aggregation, light olive-g~een ~o ~ig~t tan in color. Microscopic examination detected no living cells 24 hours after pH 3.5 was reached. Discussion

Taxonomy

The systematics of blue-green alga~ are in revision primarily because morphological characteristi9s, used in some taxonomic keys (e.g. Prescott 1962, Tiffany and Bri~ton 1952), were observed to vary µnder diffeFent laboratory and field C?nditions for a ~iven al~al isplate. For example, Pearson and Kingsbury (1966) observed that sheath size and consistency, color of trichomes, cell diameter, type of crosswall constriction and macroscopic -morphology of a Lyngbya isolate varied with culture conditions and at times in identical culture coqditions within the same flask. In fact, some Lyngbfa ~henotypes p~oduced in Pearsons and Kingsbury's study would key to Oscillatoria or Phormidium in Prescott's (1962) taxonomic key.

Using stable morphological characteristics of the protoplast, Drouet (1968) reduced 24DO described species of Oscillatoreaceae to 23 species in six genera. Although Drouet's critics generally agree that a revision was necessary, his work has met criticism because of the lack of genetic and physiological studies t9 augment Drouet's morphological observations. Stam and Holleman's (1975,1979) and Stam and Venema's (1~77) works suggest the

14 15

limitations of Drouet's revision and illustrate the difficulty of using current taxonomic keys for identifying the blue-green algae·. They studied 23 strains of Schizothrix calcicola Csensu Drouet>,'"'mostly from the Indiana Culture Collection, driginally identified as nine species of Phorrnidiurn, Plectonerna, Lyngbya and Schizothrix. By'DNA hybridization techniques and comparative morphological studies in varying culture conditions, they observed three differen~ taxa which th~y identified as Phormidium spp.

A similar plasticity in sheath consistency, crosswall constriction, protoplast granulation and cell length was observed in blue-green a1g'ae Isolated from algal mats or sediment samples in this study. Preserved specimens key to

Phorrnidiurn, Lyngbya or Schizothrix in Prescott's (1962) and Tiffany and Britton's (1952) taxonomic keys depending on the condition of the sheath material. Live specimens from laboratory cultures of the· same algae key to Phorrn·idium minnesotense (Tilden> Drduet or Phormidiurn tenue (Meneqhini) Gomont in Tiffany and Britton's (1952) key or

Phormidiurn minnesotense in ~rescott's (1962} key. Drouet's (1963) Schizothrix calcicola description covers the range of variation observed in the ~ield and in laborat6ry cultures of the species isolated in this ·study. Furthermore, when the four strains of ~.calcicofa from tne four acidified lakes are grown in the same defined media, 16 they are identical in morphology and showed a similar pH tolerance (fig. 1). In �eneral, the dominant, but closely related species, forming blue-green: algal mats in acidified lakes are all small filamentous .Oscil,latoriaceae species which secrete extracellular sheath material (table 4).

Algal Mat Development

An algal mat consists of intertwined filaments and extracellular gelatinous material which forms a more or less cohesive fabric (Golubic 1976). When alga1 mats spread over loose sediments they can trap and bind particles and physically stabilize the water sediment interface (Wray 1977, Golubic 1976). As material (silt,sand, detris) is deposited on the mat surface algal filaments penetrate upwards to recolonize the surface, forming layered or laminated structures (Wray 1977). Environmental factors such as light, oxygen supply and ion concentrations can vary along vertical gradients within the developed mats (Golubic 1976). Algal mats can be viewed as minature ecosystems which modify and stablize the microenvironment within the mat (Golubic 1976).

These brganosedimentary structures can form providing-that: Cl) the environment is suitable for growth of the mat ' forming organism; (2) the rate of g'ro�th exceeds the rate of consumption by other organisms; (3) the rate of J 17

sedimentation does not exceed recolonization at the fluid-biosediment interfacei (4) the mat layers accre~e faster than they can be destroyed by boring and burrowing organis~s and erosive or other mechanical and chemical forces (Walter 1976). The resulting structures called stromatolites are well represented in the fossil record and are some of the ol.dest preserved traces of li'fe (>3,.000 million years old) CAwrarnick At .al. 1976). Blue-green algae and bacteria are believed to be the dominant or.ganisms which bui'lt fossil str.omatolites (Awrarnik At .al. 1976). Although relatively rare, modern-day analogs are found throughout the world in a variety of aqueous environments hut are generally restricted to areas of extreme light 1ntensity, temperature, alkalinity and/or sqlinity (Parker ..e.t. .a..i. 1981). Thes~ algal mats are most common in envi~onments of carbonate sedimentation, but are al$O found in environments of elastic silicate ~edimentation (Awrc;unik At .a.l. 1978, Parker .et .a.l. 1981).

We are not aware of any reports in the literature identifying the algal mats found in acidified lakes or other acid environments as stromatolite analogs 1 Walter 1976, Awramik At .al. 1978, Par~e~ ..e.t. .al. 1981). Blue-green algae have historically been thought to pr.efer neutral or alkaline habitats. Brock (1973) states ,that blue-green aJgae are rare or absent below pH 6.0 and do not exist below a pH of 4.0. Yet blue-green algae are well 18 represented .. in the floras of a number of acidified lakes, as phytoplankton (Lind and Campbell 1970, Kwiathowski and Roff 1976, Conroy~ .al. 1976, Hendrey and Wright 1976) and as extensive benthic mat assemblages (Hendrey and Vertucci 1980, Lazarek 1982a, this study). The predominantly blue-green algal mats in acidified lakes are structurally similar to those described as stromatolite I. analogs.

The existence of extens~ve ~lue-green al~~l mats at low pH is surprising in view of Brock's (1973) ~ork that states blue-greens are rare or absent below pH 6.0. Even laboratory studies of optimum pH ranges (Kratz and Myers 1955, McLachlan and Gorham 1962, Allen 1952) and ~ physiological responses at low pH (Coleman and Colman 1981, Kallas and Castenholz 1982a) of blue-gFeen algal cells indicate little or no survival at low pH (generally

survival and slow growth did occur at low pH (figs. 3b, 4b). Batch cultures buffered at low pH (4.0, 5.0), initially decrease in cell density but show a steady increase in cell densities thereafter (fig. 4b). The ! initial decrease is probably caused by the rapid change from a neutral ~reexperimental (pH 7.0, full strength medium) , to an acid experimental (pH 4 •. 0 or 5. O, reduced strength medium) condition. Nevertheless, ~.calcicola did grow at a low pH.

The question arises as to whether Schizothrix is a recent addition or was a previous inhabitant of the plankton or sediments of these acidified lakes. This is difficult to answer because of the lack of a previous data base. However, ~.calcicola is one of the most widely distributed, occuring in both the marine and freshwater plankton and benthos, and hardy of all species of Oscillatoreaceae CDrouet 1963,1968). In this study, ~.~alcicola was found in benthic samples in all seven lakes (pH range 6.15 to 3.45) but had formed algal mats in only two lakes (table 4). While the development of blue-green algal mat.~ is a recent phenomenon in some acid lakes, the dominating mat species may have been in the lake previou~ly.. •

We have established that growth of ~.calc~cola can occur at low pH. Do algal mats develop only from established benthic organisms or can mats develop from planktonic forms 20 of Schizothrix. Our laboratory experiments suggest one mechanism of ~.calcicola mat formation. Suspended filaments of ~.calcicola, growing at high pH, aggregate and settle out of solution and attach to th'e flask bottom forming a· mat-like structure when the pH of the culture is lowered (fig. 6). Although little or no work on blue-greens' flocculation and coagulation is evident, considerable work on the mechanisms involved in coagulation and flocculation of microorganisms Cespcially bacteria) is avail~ble. Coagulation arid floc6ulation of particles occurs when the repulsive forces which keep particles suspended are overcome or reduced (Singley 1971). Microorganisms aggregate due to the interaction of external polymers (such as the polysaccharides in blue-green algal sheaths) which may form bridges of polyme~ chains between cells (Busch and Strumm 1968, Daniels 1980). Many factors influence the bioflocculation process including the growth phase of the microorganism, nutrient concentration and pH (Busch and Strumm 1968, Daniels 1980). A change in pH can reverse the capability of a bacte~ial cell to adhere to adsorbant particles (sediments, flask bottoms). This adherence or adsorption is generally strongest at pH 3.0 to 6.0 (see Daniels 1980). Clumping and settling of blue-green algae filaments ma~ be enhanced further by the gliding movement of the trichomes within their adhering mucilage sheath (Walsby 1968). 21

Water Chemistry

Elevated levels of micronutrientJ ha.ye Been suggested as a possible factor in blue-green algal ..mat development in acid lakes· (Lazarek, personal comm1J'nication). With aciditication, some macronutrients can become, l�ss available. For example phosphorus comp'Ounds coil'l'plex with aluminum, forming precipitates at pH 4.5 to 6.5 (Dickson 1980). Micronutrients (e.g. zinc, manganese, copper,. iron) an'd· heavy metals (aluminum, lead, cadmium, mercury, nickel) ha�e greater solubility at low pH (Moss 1980, Wright and Gjessing 1976, Norton .et .Al. 1981, Schindler .e.t .al. 1980) and· leach from soils, sediments or enter lakes by direct deposition (Haines 1981) becoming more available. Although elevated mictonutrient and heavy metal concentrations are toxic to most organisms some organisms regui�e .increased nutrient concentrations at low pH (Butner 1972) possibily due to an increased net surface charge which hinders nutrient uptake (Langworthy 1978). In preliminary ekperiments on the effect of increased micro and macronutrf�nts at low pH no significant effect on growth was observed •

.s.calcicola growth is not enhanced by elevated micro and macronutrient levels, is not acidophilic and displays only slow growth at Iow pH in the laboratory. Yet it dominates the littoral as algal mats in Limekiln and parts of Big 22

Moose Lakes. The existence of blue-green algae in acid environments may partly be a result of the algal mat system's ability to modify the hydrogen ion concentration within the mat. In our laboratory, cultures of a.calcicola raised the pH of unbuffered media over four pH units in two-week old unshaken cultures. Similarly, Wildman .e..t .a.i.<1974) observed that Anabaena cylindrica, Anacystis nidulans and Nostoc muscorum adjusted the pH of culture media from stress levels (pH 4.0-6.0) to favorable levels (pH 7.0-10.0) and incr:ased the buffer capacity in one week. In an acid, poorly buffered lake, the ability to raise the pH of the mat environment would be advantageous to growth. There is some field evidence of this. In Lake G!rdsjon, Sweden interstitial mat water was found to be higher (pH 5.5-6.2) than the overlying water (pH 4.3-4.7) depending on the time of day (Lazarek 1982a, Lazarek personal communication).

The algal mat may be the result of community succession in an acid environment with a low sediment rate relative to the recolonization rate of the algae. With gradual acidification of lakes the following may happen: (1) the step-wise elimination of acid-intoleran,t algae and macrophytes occurs. In general, environmental extremes tend to exclude or restrict competing eucaryotes in stromatolite analogs (Garrett 1970, Brock 1976, Golubic 1976). (2) Grazing pressure and burrowing is probably 23

reduced as benthic invertebrates decrease in abundance (Raddum 1980, Okland and Okland 1980). Stromatolites reached their greatest diversity and distribution duri ng the late precambrian, before the advent of metazoans: the evolution of grazing, burrowing and competing organisms may have been the controlling factor in the decline of strom�tolites from cambrian times �o the present (Garrett 1970, Gebelein 1976). (3) The acid conditions of the overlying water further enhance clumping and aggregation of algal filaments and reduces decomposition processes, allowing a buildup of dead filaments and sheath materials. The end result through a community succession process is an algal mat wbich can be thought of as a physiologic unit (Lazarek 1982), potentia11r capable of modifying its immediate environment. LITERATURE CITED

Allen. M.B., 1952. The cultivation of the Myxophyceae. Arch.Mi~robiol. 17:34-53. Almer, B., W~Dickson, E.Ekstr6m and E.H~rnstrBm. 1978. Sulfer pollution and the aquatic ecosystem. In: Sulfer in the Environment. J.O.Nri-asgu {ed.}. John Wiley and Sons, New York and Toront,p. 482 p. Almer,B., W.Dickson, E.Ekstr~m, t.B6rnstrrim and a.Miller. 197 4. Effects of acidification on Swj;!di-~h la,k_es. AMBIO. 3:30-36. American Public Health Associ~tion. 1975. Standard Methods fo~ the Examination of Water and Wastewater. 14th edition. Wash. DC. 1139 p. Awramick, S.M., L.Margulis and E.S.Barghoorn. 1976. Evolutionary processes in the formation of stromatolites. In: Stromatolites.M.R.Walter Ced.). Elsevier Scientific Publishing Co., Amsterdam, Oxford, New York. 790 p. Awramick, S.M., C.D.Gebelein and P.Cloud. 1978. Biogeological relationships of ancient stromatolites and modern analogs. In: Environmental Biogeochemistry and Geomicrobiology. Vol.l: The Aquatic Environment. W.E.Krumbein (ed.}. Ann Arbor Science Publishers Inc., Mich. 1055 p. Beamish, R.J., W.u.Lockhart, J.C.Van Loon and H.H.Harvey. 1975. Long-term acidification of a lake and resulting effect on fishes. AMBIO. 4:98-102. Brock, T.D. 1973. Lowet pH limit for the exi~tence of blue-green algae: evolutionary and ecological implications. Science. 179:480-483. Brock, T.D. 1976. Environmental mtcrobiology of living stromatolites. In: Stromatolites. M.R,Walter Ced.}. Elsevier Scientific Publishing Co., Amsterdam, Oxtord, New Yot~. 790 p. Burnham, J.C., T.Stetak and J.Boulger. 1973. An improved method of cell enumeration fo~ filamentous algae and bacteria • .J.Phycol. 9:346-349. Busch, P.L. and w.stumm. 1968. Chemical interactions in the aggregation of bacteria biQflo~culation ip w.sste treatment. Environ.Sci.Tech. 2(1):49-53.

24 25

Coleman, J.R. and B.Colman. 1981. Inorganic carbon accumulation and photosynthesis in a blue-green alga as a function of external pH. Plant Physiol. 67:917-921. Confer, J.L., T.Kaaret and G.E.Likens. 1983. zooplankton diversity and biomass in recently acidified lakes. Can.J.Fish.Aquat.Sci. 40:3.6-42. Conroy, N., K.Hawley, W.Keller and C.Lafrance. 1976. Influences of the atmosphere on.lakes in the Sudbury area. Great Lakes Research. 2Csupp.'l):146•165. Daniels, S.L. 1980. Mechanisms involved in sorption of microorganisms to solid surfaces. In: Adsorption of Mrcroorganisms to Surfaces. G.Bittan and K.C.Marshall (eds.). John Wiley and Sons Inc., ~ew York and Tor~nto. 439 p. Dickson, w. 1980. Properties of acidifierl water. In: Proc.Int.Conf.Ecol.Impact of Acid Precipitation. D.Drablos and A.Tollan (eds.>. SNSF Project, Asa, Norway. Drouet, F. 1963. Ecophenes ~f schizothrix calcicola. Proc.Aca"'d.·Nat.Sci.Phil. 115 (9) :261-281.

·Drouet, F. 196 8. Revision of the Classification of. the Oscillatoriaceae. Monograph 15. The Acad.Nat;Sci. 370 p. Garrett, P. 1970. Phanerozoic stromatolites: noncompetitive ecological restriction by grazing and burrowing animals. Science. 169:171-173. Gebelein, C.D. 1976. The effects of the physical, chemical and biological evolution of the earth. In: Stromatolites. M.R.Walter Ced.). Elsevier Scientific Publtshing Co. Amsterdam, Oxford and. New Y~rk. 790 p. Golubic, s. 1976. Organisms that built stromatolites. In: Stromatolites. M.R.Walter Ced.). Elsevier ~cientific Publishing Co. Amsterdam, Oxford and New York. 790 p. ~ Haines., T.A. 1981. Acid precipitation and its consequences for aquatic ecosystems. Trans.Am. Fisb. Sci. 110:669-.7 07. · .. Hendrey, G.R. and P.A.Vertuccf. 1980. Benthic plant communities in acidic Lake Colden, New York: Sphagnum and the algal mat. In: Proc.tnt.Cortf.Ecol.Impact .ncid Precipitation. D.Drablos and A.Tollan (eds.). 26

. SNSF Project, Asa,Norway. Hendery, G.R. and R.F.Wright. 1~76. Acid precipitation in Norwayt effects ·on aquatic fauna. Great Lakes Reaearch. 2(suP.p.l):192-207. Hendrey, G.R., K.Baalsrud, T.S.Traaen, M.Laake and G.Raddum. 1976. ·Acid precipitation: some hydrobiolQgical changes. AMBIO. 5:224-227. Hoshaw, R.W. and J.R.Rosowski. 1973. Methods for microscoRic algae. ~n: Phycological Methods. J.R.Stie~ (ed.). Cambridge Univ.Press., New York. 448 p. Hultberg~&. and Q.Gran. 1976. Eftecti of acid . precipitatiqn on.m~qrophytes .in oligotrophic Swedish lakes. Great Lakes Research. 2(supp.l):208-217. . r Butner, S.H. (1972). Inorganic nutrition. Ann.Rev.Microbiol. 26:313-181. Kallas, T. .and R.Castenholz. 1982a. Internal, pH and ATP-AQP pools in the Cyanobacterium Synechococcus sp. during exposure to growth inhibiting low pH. J,Bacteriol. 149(1):229-236. Kallas, T. and R.W.Castenholz. 1982b. Rapid transient growth at low pH in the Cyanobacterium Synechococcus sp. J.Bacteriol. 149(1):237-246. Kratz, W.A. and J.Myers. 1955. Nutrition and growth of several blue-green algae. Am.Jour.Bot. 42:282-287. Kwiatkowski, R.E. and J.C.Roff. 1976. Effects of acidity on phytoplankton and primary productivity of selected northern Ontario lakes. Can.JJ3ot. 54:2546~2561. Langwortpy, T.A. 1978. Microbiol life in extreme pH values. In: Microbial Life in Extreme Environments. D.J.Kushner Ced.). Academic Press, New York. 465 p. Lazarek, s. University of Toronto, Toronto, ~anada M5s 1A4. Lazaiek, s. 1980. Cyanoppytan mat communities in acidified l,ak~s., ,Naturwi,.ssenschaften·. 67: 97..:--98. Lazarek, s. 1982a. Structure and function of a Cyanophytan mat community in an acidified lake. Can.J.Bot. 60(11):2235-2240. Lazarek, s. 1982b. Structure and productivity ofr epiphytic algal communities on Lobelia dormanna L. in 27

acidifed and limed lakes. Water, Air and Soil Pollution. 18:333-342. Lazarek, s. 1983. Structural ang functional aspects o! epiphytic and benthic algae in the acidified Lake Gardsjon, Sweden. Phd.Thesis. Univ.of Lund, Lund Sweden. Lee, G. Dept.of Environ.Conservation, ~oose River ·R~creation Area, New York. Lind, o. and R.S.Campbel'i. 1970. Community metabolism in acid and alkaline strip-mine lakes. Trans.Am.Fish Soc. 99:577-582. · . McLachlan, J.L. and P.R.Gorham. 1962. ~ftects of pH and nitrogen sources on growth of Microcystis aeruginosa Kutz.· Can.J.Microbiol. 8:1-11. ~- Moss, B. 1980. Ecology of Freshwaters. Blackwell Scientific Pulblications, Oxford. 439 p. Muller·, P. 1980. Effects of artificial. acidj.fication on the growth of periphyton. Can.J.Fish Aquat.Sci. 37:355-363. Nichols, B.W. 1913. Growth media~ freshwater. In; Phycological Methods. J·. R. Stein Ced;:.) • Cam}:;)rJdge Dniv.Press, New York. 448 p. . Norton, S.A., R.B.Davis, D.F.Brakke, D.W.Hanson, K.H.Kenlan and P.R.Sweets. 1981. Responses of Northern New England Lakes to Imputs of Acids and Heavy Metals. Completion report Project A-048-ME. Land and Water Resources Center, Univ.of Maine at Orono. 90 p. Okland, J. and K.A.Okland. 1980. pH level and food organisms for fish: studies of 1000 lakes in Norway. In: Proc.Int.Confer.Ecol.Impact Acid Precipitation. D.Drabols and A.Tollan (eds.). SNSF Project, Asa, Norway. Parker, B., G.M.Simmons,Jr., F.Love, R.A.Wharton,Jr. and K.G.Seaburg. 1981. Modern stromatolites in Antartic dry valley lakes. Bioscience. 31(9):656-661~ Pearson, J.E. and J~M~Kingsbury. 1966. ~ulturally induced variation in four morphologi~ally diverse bluegreen algae. Am.J.Bot. 53:192-200. Pfeiffer, M.H. Dept.of Environ.Coservation, Ray -~roo~, New Yorkr1 Pfeiffer, M.H. and P.J.Festa. 1980. J\cidity status of 28

lakes in the Adirondack Reigon of New York in relation to fish resources. NY State Dept.of Enviton.Conservation Te~h.Bull. FWP168. Albany, ~Y.

Prescott~ G.W. 1962. Algae of the Western Great Lakes Area. w.c.Brown Co. Dubque, Iowa. 977 p.

J Raddum1 G.G. 1980. Comparison of benthic invertebrates in lakes with different acidity. In: Proc.Int.Conf.Ecol.Impact Acid Precipitation. D.Drablos and A.Tollan (eds.). SNSF Project, Asa,Norway. Raddum, G.G., A.Hoback, E.R.Lomsland and T.Johnsen. 1980. Phytoplankton and zooplankton in acidified lakes in south Norway. In: Proc.Int.Conf.Ecal.Impact Acid ~recipitation. D.Drablos and A.Toll~n (eds.>. SNSF Project, Asa,Norway. Roff, J.C. and R.E.Kwiathowski. 1977. Zooplankton and zoobenthos communities of selected northern Ontario lakes of different acidities. Can.J.Zool. 55:899-991. Schindler, D.W., R.Wagemann, R.B.Cook, T.Ruszczynski and J.Prokopowich. 1980. Experimental acidification of Lake 223, Experimental Lakes Area: background data and the first three years of acidification. Can.J.Fish.Aquat.Sci. 37:342-354. Schofield~ C.L. 1976. Acid precipitation: effects on fish. AMBIO. 5:219-221. Singley, J.E. 1971. Chemical and physical purification of water and wastewater. In: Water and Water Pollution. L.L.Ciaccio Ced.). Marcel Dekker Inc., New York. 1945 p. Sorokin, c. 1973. Dry weight, packed cell ~olume and optical density. In: Phycological Methods. J.R.Stien (ed.). Cambridge Univ.Press, New York. 448 p. Stam, W.T. and H.C.Holleman. 1975. The influence of different salinities on growth and morphological variability of a number 'of Phormidium strains (Cyanophyceae} in culture. Acta.Bat.Neerl. 24(5-6):379-390.

------. 1979. Cultures of Phormidium, Plectonema, Lyngbya and synechococcus CCyanophyceae> under diffe~e.nt conditions: their growth and morphological variability. Acta.Bot.Neerl. 28(1):45-66. 29

Stam, W.T. and G.Venema. 1977. The use of DNA-DNA hybridization for determination of the relationship between some blue-green algae (Cyanophyceae). Acta.Bot.Neerl. 26(4)327-342. Tiffany, L.B. and M.E.Britton. 1952. The Algae of Illinois. Univ.of Chicago Press, Chicago. 407 p. Talling, J.F. 1973. The application of some electrochemical methods to the measurement of ~ photosynthesis and respiration in fresh waters. Freshwat.Biol. 3:335-362. ~ Traaen~ T.s. 1980. Effects of acidity on decomposition of organic matter in aquatic environments. In: Proc.Int.Conf.Ecol.Impact Acid Precipitation. D.Drablos and A.Tollan (eds.>. SNSF Project, Asa, Norway. Vertucci, F. Cornell University, Ithaca, New York. Walsby, A.E. 1968. Mucilage secretion and the movement of blue-green algae. Protoplasma. 65:223-238. Walter, M.R. 1976. Introduction. In: Stromatolites. M.R.Walter Ced.). Elsevier Scientific Publishing Co. Amsterdam, Oxford, New York. 790 p. Wildman, R.B., B.L.Benner, D.D.Held and c.w.schauberger. 1974. Influence of blue-green algae on the pH and buffer capacity of culture media. Proc.Iowa Acad.Sci. 81(4):192-196. Wray, J.L. 1977. Calcareous Algae. Elsevier Scientific Publishing Co. Amsterdam, Oxford, New York. 185 p. Wright, R.F. and E.T.Gjessing. 1976. Acid precipitation: changes in the chemical composition of lakes. AMBIO. 5:219-~23. Yan, N.D. 1979. Phytoplankton community of an acidified heavy metal contaminated lake near Sudbury, Ontario. Water, Air and Soil Pollution. 11:43-55. Yan, N.D. and R.Struss. 1980. Crustacean zooplankton communities of acidic metal-contaminated lakes near Sudbury, Ontario. Can.J.Fish.Aquat.Sci.• 37:2282-2293. Zar, J.H. 1974. Biostatistical Analysis. Prentice Hall Inc. New Jersey. 620 p. TABLE ONE Location, Elevation and Surface Area of Lakes Sampled in the Adirondack Mountains of New York During the Summer of 1982. Lake County of Elevation Surface ·Area N.Y., USA in Meters in Hectares Big Moose Lake Herkimer 556 514.4 Cellar Pond Hamilton , 909 2-�4 Dart Lake Herkimer ·535 56.4 Falls Pond Hamilton 759 15.2 Fourth Lake Herkimer 609 868. 4 Limekiln Lake . Herkimer 575 184·.·4 Wolf Lake t1amilton 793 5.2 TABLE TWO · Temperature, pH and Alkalinity of Adirondack Lakes Sampled.

Lakes pH Temp Alkalinity+ ( o C ) (.ueq/ liter) sur Bot sur .... Bot Sur Bot++ ·Fourth Lake June 82 6.15 6.15 18. 5 17,5 <10 <12 * Limekiln Lake 22 Oct. 81 5 .3 0 4.0 1 Ju+y 82 5.20 5.20 18.0 18. 0 < 2 < 2 * 20 Aug. ~2 4.60 4.60 22.0 22.0 -56 -91 ** Falls Pond 22 June 82 4.50 4. 70 20.0 20.5 < 2 * 21 Aug. 82 4. 20 4. 50 19.4 19.8 -43 17 ** Dart Lake

29 June 82 4. 45 4. 6 o 2 o. O < 2 < 2 * Big Moose Lake

2~ June 82 4.10 4.40 !9.0 < 2 < 2 * 23 Aug. 82 4. 00 4.00 19.0 -45 -94 ** Cellar Pond 30 June 82 3.80 3.70 17.0 15.0 < 1 < 1 * 22 Aug. 82 3.65 3.70 15.2 15.4 -138 -165 ** Wolf Lake 28 June 82 3. 5 0 3. 5 0 23. 0 21.s < 1 * 21 Aug. 82 3,45 3.70 18.5 18. O -122 -14_7 ** + negative alkalinity indicates acidity ++Sur= Surface, Bot= Bottom * alkalinity measured by potentiometric titration ** alkalinity measured by Gran titration analysis. TABLE THREE Partial List of Algal Genera Identified From Preserved .Benthic Samples. Genera Lakes FL LL FP PL BML CP WL Cyanophyta S~bi ,rn:tb t: ix 0 A F F A 0 A HapalQsigbQD 0 A 0 Cbt:QQ~QCC!.1S F F .,.. F F Met:ismQpedia F 0 F F F Mict:Qcystis 0 Chlorophyta MQ1.1gegtia F A 0 Mict:QS£2Qt:a A :aulb2£hsu~te F 0 0 a121·1:: Qgy ta F :eeoimn F 0 F

Diatoms A F A F F A F :aatt:acbos;gez.:mum F F A A

Fourth Lake = FL Limekiln Lake = LL Falls Pond = FP A = Abundant Dart Lake = DL F = Frequent Big Moose Lake = BML 0 = Occasional Cellar Pond = CP = None observed Wolf Lake = WL TABLE FOUR Dominant Blue-green Algae in Mat Systems in Acidified Lakes. Algae pH Lake

Phormidium tenue 4.8 Colden, USA. C=SchizQthrix calcicola) CBendrey and Vertucci 1980) Lyngbya bourrellyana 4.3 Gardsjon, Sweden C=Phormidium amhiguim) (Lazarek 1982) Schizothrix calcicola 4.1 Big Moose, USA C=Phormidiurn minnesotense> s.2 Limekiln Lake, USA (This study) Schizothrix Friesii 3.5 Wolf, USA C=Phormidium indunatum> (This Study) fIGUBi 1

10 �BML / 9

8 /9-...... II E ~WL . • Ii LL 0 7 LC) � ,! Q) 6 1! 1! ? FP bD II I E 5 C Ii ,' .c+-' 4 /! I bD /f I · a, 1! I � 3 /I I � 0 2 I·f ) / / 1 II•/ LL _..o._ , '"� FP o---o..... ' • ---o-- :/T 0 BML �• . .-o:;;,--o-·�/' o/ WL o· "-

4.0 4.5 5.0 5.5 6.0 6.5 7 .0 pH Fig. 1. Growtll versus pK of S.1timothr1x caleieola isolates trOll Liaekiln Lake (LL), Falls Pond (rP), Big Moose Lake (BML), and Volt Lake (WL). Plot ot aeans (n • )). Pooled standard deviation& LL• • 15, FP • .69, BML • 1.86 , WL • .86 mg/50 al. FIGURE 2 Results of the Newman-Keules Multiple Range Test

Schizothrix calcicola pH Level Isolates From: Limekiln Lake Controi t4• 0 4.5 s.o s.s,,6.o .. 7.0116.51 ~ . Falls Po,nd ,CQntrpl L4. o 4.5 s.o s.s 6.0 6.s 1 LL.QJ

f, Big Moose Lake t Control 4.0 4.5 s.o s.s 6.0,16.S 7. o,

Wolf Lake I Control 4.0 4.5 s.o s.s 6.0116.S 7. 01

---~~-J = Range with no significant difference in growth. (measured by dry weight) Control= Zero growth FIGURE 3

Growth 6f Schizothrix calcicol a (Limekiln Lake isolate) in reduced strength unbuffered (Fig.3a) and buffereI d (Fig.3b) 5 medium. Pooled standard deviation Fig.3a = 1.24 x 10 · cells/ml, Fig.3b = 1.37 x 1fcells/ml. Replicates =�. I a. FIGURi 3

5.0

LO 0 .-f X 2.0 E I,... Q) a. (/) Q) 1.0 () Initial Cell Density .34 """::-,.--- ...... ------:...-...... _...,.~_..... -r- ·-- --

.10 .25 .50 1.00 Media Strength - Unbuffered b. ______Initial Cell Density ....;.______, ____ _ 4 .9 v 0....., 2.0- X -E I,... Q) a. 1.0- J!l. -Q) ()

.125 .250 .375 .500 Media Strength- Buffered pH 4.00 FIGURE 4

Growth curves of Schizothrix calcicola in pH 6.0 and 7.0 CFig.4a) and pH 4.0 and 5.0 (Fig.4b) buffered media. I Values represent mean cell count (n = 3 ). A Limekiln Lake isolate was used. Pooled ~tandard deviation: pH 7.0 = 2.49 x 10 6 cell/ml, pH 6.0 = 3.45 x 10 6 cells/ml, pH 5.0 = 2.00 x 104 cells/ml and pH 4.0 = 1.5 x 104 cells/ml. a. FlGU.ttE 4

3 :,.-_ ' ' ' ' ' ' ' pH6 ' ' 2 ' ' I ' I ' I ' I ' ~ ' Q) I ' 0.. ' (/) , ' ' -Q.) 1 I ' I ' • pH7 u I I I

::>. 8 epH5 I I I I I I 6 JI pH4 "1" / 0 / .-i ...., X / ' ' \ I E 4 \ I I lo.... \ I Q) \ I \ \ I I 0.. 1 I (/) ' \ I \ • \ I Q) \ I u 2- ,, i

2 3 4 5 6 7 8 9 10 11 12 13 14

Day FIGURi: 5

r I 6 I '':::::::..- I ..... --- I oi::::1- 5 ...... -. -- -. Control 0...... -----+ ...... X 4 ...... ,..._ .. I . E + Nutrients Ji... 3 Q) l a. I J!). 2 I -Q) ' C.) 1

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Time in Days Figure 5. Growth -of Scnizothrix ealcicola (Liaekiln Lake) in half strength buffered (pH 4.0) aedia with' and without added nutrients. Bars re)?Z'esent standard deviation of a• 4 replicates. FIGURE 6

Plot of percent suspended al9ae CSchizothrix calcicola Limekiln Lake isolate) versus decreasing pH. 100 � = suspended algae before titration. Plot of mean percentage of cell counts/ml. Bars represent standard deviation C n = 3 ) • Percent Suspended Cells

N Q") 00 0 0 0

,_. 0

/ --f / ;- / N I I 00 I / >sJ I a I c: I � I °' ,l / / /

I I I I I I I

w APPENDIX AI

Picture of algal mat in Limekiln Lake 'taken from boat through ca. 0.5 meters of water, August 1982. Jew York State Department of Environmental Conservation urvey & Inventory Unit ay Brook, New York 12977

Henry G. Williams Commissioner

July 25, 1983

Ms. Maureen A. Leupold Dept. of Biological Sciences SUNY College at Brockport Lennon Hall Brockport, New York 14420

Dear Ms. Leupold:

Your recent correspondence to Walter Kretser concerning the New York State liming program has been relayed to this office for reply. The only lake in your listing of seven study lakes which has received state spon sored lime treatments is Falls Pond. This received five tons of hydrated lime in 1975 and 20 tons of agricultural limestone in 1978.

However, private landowner organizations are also in the volunteer li~ing business and, thus, the North Bay of Big Moose Lake has received several lime treatments in the past. I am not personally aware of any liming project at Fourth Lake but it is possible that some individuals are engaged in neutralization efforts. At the present time we do not have any direct control over private liming, although we are attempting to form alize volunteer liming through the Adirondack Conservation Council Volunteer Liming Task Force.

Sincerely,

Martin H. Pfeiffer Lake Acidification Studies Project Leader

MHP/TEF L1MNOLOGISKA I NSTITUTIONEN INSTITUTE OF LIMNOLOGY University of LunJ Lund /\pril 11th, 1~8~

~l;1ureen A. LcupolJ

S LI t e ll ll j V <: r S i t y O f NC \v YO r k t:l)J legc at Brockport BROCKPORT, N.York 14420

Thank you for your Jetter and the abstract from Proceedings or the Rochl'ster Academy of Science. I "'as very glad to hear :1bout your studies. Your letter arrivcJ when I was completing my Ph.D. thesis at the University ur Lund. The thesis will be disputed on the lllth or May, l!l83. In the summary of the thesis, I refer to your short note about h1ul'-grecn algal mats in the Adirondacks, ti> support an idea that the forma.tion of blue-green :llgal mats is not an unusual response to acidification.

J.n 1981, during a stay at the Brookhaven Nat. Laboratory, visitcJ Sl'vcral places in .\dirondacks with the help of the Acid (;roup hut I was not :1ble to collect any samples or hcnthic blue-green algae. The short note by Hendrey & v~rtucci (1980) confirmed my observations. I have samples from a few other places in SweJen where such algal mats occur - the principal algal species all belong to Oscillatoriacae.

You wrote that your algae 1lid not grow in the buffered mcJia. Well, this is exactly what I experienced while trying ' ; to grow my :11 gae on the Camh ridge cyanophycean agar (~CAP Ct~lturc Collection, Cnmhridgc). 2 .

I could not successfully keep algae growing just by changing the pH of the med i u ( range 4. .2-7. 0). I hecame convinced that some other environmental factors (perhaps same microelements) are necessary for the growth of these algae. In fact, I have obtained continuous growth of my algae, retaining their mat structure, in big Petri dishes. The dishes were filled with the sediment from L. Gardsjon and lake water was periodicaly added. In the lake, the pll whithin the mat was around 5-6, measured with a pH-electrode. The electrode could not be used satisfactorily jn the field, and I preferred (for the purpose of the publicatjon) to measure the pH of the water gently p1"Csse

Algal Mat in Wolf Lake

Schizothrix Friesii, the dominant mat forming blue-green algae in Wolf Lake, failed to grow in defined media [Chu# 10, Guillards, Bristols (Nichols 1973)] or soil water medium. Liquid and soild (1.3% agar) substrates were used along with a range of medium dilutions and pH levels. Yet, abundant growth was obtained in a natural sample kept on a window sill in unfiltered Wolf Lake water. It is possible that S.Friesii has specific macro and micronutrient requirements that were not provided in the culture media used. Wolf Lake is very acid CpH ranges 3.45 to 3.70) yet S.Friesii is thriving there. The environmental requirements of this species should be investigated further since reports of blue-green algae from extremely acid environments are rare. A IV

Suggestion for Future Study

Future studies should address the chemical composition of lake waters where mats have developed. It is possible that blue-green algae have greater re~istance to elevated trace metal concentrations. For instance, Oscillatoriaceae species often dominate zinc enriched environments above pH 5.0 (Shehata and Whitton 1980). The microenvironment within mats should be measured .in .s..i.tll for chemical and pH gradients. The bacteria and invertebrate fauna of mat communities should be described.

Reference

Shehata, F.H.A. and B.A.Whitton. 1981. Field and laboratory studies on blue-green algae from aquatic sites with high levels of zinc. Verh.Internat. Verein.Limnol. 21:1466-1471.