Strategies for growth and survival of antarctic oasis lake biota
Central and northern ranges of the Pensacola Mountains were studied during early November to February summer seasons of 1963-1964 and 1965-1966 and for shorter periods in several later years. No avian visits were observed in the Neptune Range in 1963-1964. However, in 1965-1966, numerous but uncounted visits by skuas to the large midden of a 40person helicopter base facility in the north-central Neptune Range were doubtless attracted by the abundant helicopter, LC-130 Hercules, and R4D aircraft activity that summer throughout the Pensacola Mountains. During work in January 1974 and November-December 1976 and 1978 in areas of the Dufek Massif and the Forrestal Range, lying north of the Neptune Range, birds were sighted on but a single occasion: in midDecember 1978, two snow petrels were seen from afar flying over Davis Valley (82°30' S 51° W) at the northeast end of Dufek Massif (Reynolds fieldnotes). Near the south margin of the Filchner Ice Shelf and only about 500 kilometers from the Weddeli Sea, this broad ice-free valley containing a small pond, algal mats, and abundant meltwater would appear to be attractive to seabirds. The sighting of the two birds in but 4 days of work in the valley suggests that it is.
Strategies for growth and survival of antarctic oasis lake biota
BRUCE C. PARKER, ALFRED T. MIKELL, and GEORGE M. SIMMONS, JR. Biology Department Virginia Polytechnic Institute and State University Blacksburg, Virginia 24061
The primary aim of our 3-year study was to characterize the extent to and mechanisms by which organisms native to the unusual southern Victoria Land lakes are adapted for survival and growth under certain environmental extremes. The second year report addressed adaptations of algae, heterotrophic bacteria, and an aquatic moss to low light, low temperature, hypersalinity, and high concentrations of dissolved oxygen. We also discussed adaptations of the lakes' modern algalbacterial stromatolites to nonturbulence and the absence of metazoa (Parker et al. 1982a). Additional new information on these lakes include Cathey and others (1982); Kaspar and others (1982); Love and others (1982, 1983); Parker and others (1982b, c); Seaburg, Kaspar, and Parker (in press); Seaburg and Parker (in press); Simmons and others (1983); and Wharton, Parker, and Simmons (in press). During this third year, we have furthered our understanding of the adaptations to low light, low temperature, high dissolved oxygen; also, we have obtained new 220
References
Axelrod, B. 1979. Observations of south polar skuas at Dome C. Antarctic Journal of the U.S., 14(5), 173. Eklund, C. R. 1964. The antarctic skua. Scientific American, 210(2), 94-100, Halle, L. J . 1973. Eagle of the South Pole. Audubon, 75(2), 84-89. Reynolds, R. L. 1978. Field notes (personal communication). Ricker, J. 1964. Bird records of Victoria Land, 1962-63. The Emu, 64(1), 20-27. Rugh, D. J . 1974. Bird sightings in Marie Byrd Land. Antarctic Journal of the U.S., 9(4), 103-104. Schmidt, D. L. 1983. Personal communication. Schmidt, D. L., and A. B. Ford. 1963. U.S. Geological Survey in the Patuxent Mountains. Bulletin of the U.S. Antarctic Projects Officer, 4(8), 20-24. Splettstoesser, J . E 1981 Bird sightings in the Ellsworth Mountains and other inland areas. Antarctic Journal of the U.S., 16(5), 177-179. Watson, C. E. 1975. Birds of the antarctic and sub-antarctic. (Antarctic Research Series, American Geophysical Union). Washington, D.C.: American Geophysical Union.
evidence for phosphorus limitation and stromatolite structure, distribution, and lipid content. Low light. Seaburg and others (in press) have produced the first estimate of the photosynthetic quantum efficiency for a phytoplankton community in high latitude polar ecosystems, namely for Lakes Bonney, Fryxell, Hoare, and Vanda. Their estimates indicate that the phytoplankton of these four lakes either (1) convert light to organic matter more efficiently or (2) trap light more efficiently than freshwater or marine phytoplankton elsewhere. During the 1982-1983 field season microbial mat from the anoxic depths of Lake Fryxell fixed significant levels of carbon-14 bicarbonate (H 14CO 3 ) and carbon-14-acetate at in situ low-light levels. This suggests the presence of the anaerobic photosynthetic bacteria (e.g., Rhodospirillaceae, Chromatiaceae and/or Chlorobiaceae). Low temperature. Seaburg and Parker (in press) examined freshwater Virginia algae isolated from both cold (less than 6°C) and warm (greater than 20°C) habitats using methods identical with those applied earlier to antarctic lake algal isolates (Seaburg, Parker, and Simmons 1981). Comparison of data shows clearly that the antarctic lakes have a significantly higher proportion of algal taxa adapted to good growth at the colder temperatures and correspondingly are more frequently inhibited by the warmer temperatures. Experiments during the 1982-1983 field season also showed that dark respiration measured as carbon-14 dioxide ("CO,) evolution from unilabeled glucose in lake water was highest at about 12°C, less but still appreciable at 4°C, and severely inhibited at 20°C. Oxygen effects. Mikell, Parker, and Simmons (1983) have shown that high dissolved oxygen levels simulating those of the sub-ice waters of southern Victoria Land lakes severely inhibit the growth and metabolism of planktonic bacteria from the ANTARCTIC JOURNAL
oxygen saturated oligotrophic alpine Mountain Lake, Cues County, Virginia. All evidence points to an intracellular site of oxygen or oxygen byproduct inhibition. These results are in striking contrast to similar experiments conducted on the planktonic bacterial communities of the antarctic lakes where bacterial growth and metabolism were not inhibited and sometimes apparently stimulated by high dissolved oxygen levels (Mike!! and Parker in preparation). Phosphorus limitations. In situ phosphorus-33-labeled phosphate (33PO4 3) uptake rates by plankton have been conducted in the four lakes during three austral summers (Seaburg et al. in preparation.) A total of 40 tracer and 20 nontracer level experiments showed that, while turnover times for natural phosphate (PO4 3) pools were much longer than for temperate latitude lakes, phosphorus probably is a major limiting nutrient for plankton growth and productivity. Notable exceptions are at lake depths where light is severely limiting, phosphorus has accumulated, or plankton densities are very low. Stromatolites. A unique feature of at least five southern Victoria Land lakes are the benthic bluegreen algal-bacterial-diatomaceous mats which have formed modern stromatolites, representing the only cold freshwater stromatolites presently known on Earth. Various stromatolite types occur in Lakes Bonney(B), Chad(C), Fryxell(F), Hoare(H), and Vanda(V) ranging to various depths. These include columnar liftoff (B, C, F, H), aerobic prostrate (B, C, F, H, V), anaerobic prostrate (F, H, V), and pinnacle mats (B, V). Other types of mats, such as floating, frozen in ice, and moat mats are ephemeral and do not form stromatolites. Wharton and others (in press) have presented details of the mat distribution, stratigraphic features, and algal species composition and have discussed the more important variables influencing their growth and form. Recently we have begun to examine the lipids extracted from select stromatolites, including free fatty acids, fatty acid triglycerides, hydrocarbons, sterols, and steroids (Orcutt and Parker, unpublished). The undegraded, excellent preservation of these lipid components with increasing depth of select stromatolitic cores from these lakes reinforce the findings of Simmons and others (1983) that chlorophyll and adenosine triphosphate were very stable in antarctic lake sediments in contrast to temperate lake sediments. From our preliminary survey of the lipids it has become clear that the major groups of micro-organisms occurring in the stromatolitic mats and cores (e.g., diatoms, bluegreen algae and bacteria, yeasts) reflect the lipid composition. Examination of the lipids from deeper cores should contribute significantly to an understanding of biochemical diagenesis of cold freshwater stromatolites and possibly the rates and pathways of carbon cycling within these lakes.
1983 REVIEW
References Cathey, D. D., C. M. Simmons, Jr., B. C. Parker, W. H. Yongue, and M. R. VanBrunt. 1982. Protozoan colonization of artificial substrates in two Antarctic lakes. Transactions of the American Microscopial Society, 101(4), 353-367. Kaspar, M., C. M. Simmons, Jr., B. C. Parker, K. C. Seaburg, R. A. Wharton, Jr., and R. 1. L. Smith. 1982. A species of Bryum Hedw. from Lake Vanda, Antarctica. The Bryologist, 85(4), 424-430. Love, F. C., C. M. Simmons, Jr., R. A. Wharton, Jr., and B. C. Parker. 1982. Methods for melting dive holes in thick ice and vibracoring beneath ice. Journal of Sedimentology and Petrology, 43, 644-647. Love, F. C., G. M. Simmons, Jr., R. A. Wharton, Jr., B. C. Parker, and K. C. Seaburg. 1983. Modern Conophyton-like algal mats discovered in Lake Vanda, Antarctica. Geomicrobiology Journal, 3(1), 33-48. Mike!!, A. T., and B. C. Parker. In preparation. Response of the heterotrophic community to in situ high dissolved oxygen in Lake Hoare, Antarctica, Applied and Environmental Microbiology. Mikell, A. T., B. C. Parker, and C. M. Simmons, Jr. 1983. Sensitivity of an oligotrophic lake planktonic bacterias community to oxygen stress. Applied and Environmental Microbiology, 46(3), 545-548. Orcutt, D., and B. C. Parker. Unpublished data. Lipids extracted and identified from modern stromatolites in Lakes Bonney and Hoare, using gas-liquid chromatography and mass spectroscopy. Parker, B. C., C. M. Simmons, Jr., M. Kaspar, A. Mikell, F. G. Love, K. C. Seaburg, and R. A. Wharton, Jr. 1982a. Physiological adaptations of biota in antarctic oasis lakes. Antarctic Journal of the U. S., 17(5), 191-193. Parker, B. C., G. M. Simmons, Jr., K. C. Seaburg, D. D. Cathey, and F. C. T. Allnutt. 1982b. Comparative ecology of plankton communities in seven Antarctic oasis lakes. Journal of Plankton Research, 4(2), 271-286. Parker, B. C., C. M. Simmons, Jr., R. A. Wharton, Jr., K. C. Seaburg, and F. C. Love. 1982c. Removal of organic and inorganic matter from Antarctic lakes by aerial escape of bluegrass algal mats. Journal of Phycology, 18, 72-78. Seaburg, K. C., M. Kaspar, and B. C. Parker. In press. Photosynthetic quantum efficiencies of phytoplankton from perennially ice covered Antarctic lakes. Journal of Phycology. Seaburg, K. C., and B. C. Parker. In press. Seasonal differences in the temperature ranges of growth of Virginia algae. Journal of Phycology. Seaburg, K. C., B. C. Parker, and C. M. Simmons, Jr. 1981. Temperature-growth responses of algal isolates from Antarctic oases. Journal of Phycology, 17, 353-360. Seaburg, K. G., B. C. Parker, C. M. Simmons, Jr., and R. A. Wharton, Jr. In preparation. Phosphorus—A major limiting nutrient for Antarctic dry valley lakes. Polar Biology. Simmons, C. M., Jr., R. A. Wharton, Jr., B. C. Parker, and D. Anderson. 1983. Chlorophyll and adenosine triphosphate levels in Antarctic and temperate lake sediments. Microbial Ecology, 9, 123-135. Wharton, R. A., Jr., B. C. Parker, and C. M Simmons, Jr. In press. Distribution, species composition, and morphology of algal mats (stromatolites) in Antarctic dry valley lakes. Phycologia.
221
Strategies for growth and survival of antarctic oasis lake biota
BRUCE C. PARKER, ALFRED T. MIKELL, and GEORGE M. SIMMONS, JR. Biology Department Virginia Polytechnic Institute and State University Blacksburg, Virginia 24061
The primary aim of our 3-year study was to characterize the extent to and mechanisms by which organisms native to the unusual southern Victoria Land lakes are adapted for survival and growth under certain environmental extremes. The second year report addressed adaptations of algae, heterotrophic bacteria, and an aquatic moss to low light, low temperature, hypersalinity, and high concentrations of dissolved oxygen. We also discussed adaptations of the lakes' modern algalbacterial stromatolites to nonturbulence and the absence of metazoa (Parker et al. 1982a). Additional new information on these lakes include Cathey and others (1982); Kaspar and others (1982); Love and others (1982, 1983); Parker and others (1982b, c); Seaburg, Kaspar, and Parker (in press); Seaburg and Parker (in press); Simmons and others (1983); and Wharton, Parker, and Simmons (in press). During this third year, we have furthered our understanding of the adaptations to low light, low temperature, high dissolved oxygen; also, we have obtained new 220
References
Axelrod, B. 1979. Observations of south polar skuas at Dome C. Antarctic Journal of the U.S., 14(5), 173. Eklund, C. R. 1964. The antarctic skua. Scientific American, 210(2), 94-100, Halle, L. J . 1973. Eagle of the South Pole. Audubon, 75(2), 84-89. Reynolds, R. L. 1978. Field notes (personal communication). Ricker, J. 1964. Bird records of Victoria Land, 1962-63. The Emu, 64(1), 20-27. Rugh, D. J . 1974. Bird sightings in Marie Byrd Land. Antarctic Journal of the U.S., 9(4), 103-104. Schmidt, D. L. 1983. Personal communication. Schmidt, D. L., and A. B. Ford. 1963. U.S. Geological Survey in the Patuxent Mountains. Bulletin of the U.S. Antarctic Projects Officer, 4(8), 20-24. Splettstoesser, J . E 1981 Bird sightings in the Ellsworth Mountains and other inland areas. Antarctic Journal of the U.S., 16(5), 177-179. Watson, C. E. 1975. Birds of the antarctic and sub-antarctic. (Antarctic Research Series, American Geophysical Union). Washington, D.C.: American Geophysical Union.
evidence for phosphorus limitation and stromatolite structure, distribution, and lipid content. Low light. Seaburg and others (in press) have produced the first estimate of the photosynthetic quantum efficiency for a phytoplankton community in high latitude polar ecosystems, namely for Lakes Bonney, Fryxell, Hoare, and Vanda. Their estimates indicate that the phytoplankton of these four lakes either (1) convert light to organic matter more efficiently or (2) trap light more efficiently than freshwater or marine phytoplankton elsewhere. During the 1982-1983 field season microbial mat from the anoxic depths of Lake Fryxell fixed significant levels of carbon-14 bicarbonate (H 14CO 3 ) and carbon-14-acetate at in situ low-light levels. This suggests the presence of the anaerobic photosynthetic bacteria (e.g., Rhodospirillaceae, Chromatiaceae and/or Chlorobiaceae). Low temperature. Seaburg and Parker (in press) examined freshwater Virginia algae isolated from both cold (less than 6°C) and warm (greater than 20°C) habitats using methods identical with those applied earlier to antarctic lake algal isolates (Seaburg, Parker, and Simmons 1981). Comparison of data shows clearly that the antarctic lakes have a significantly higher proportion of algal taxa adapted to good growth at the colder temperatures and correspondingly are more frequently inhibited by the warmer temperatures. Experiments during the 1982-1983 field season also showed that dark respiration measured as carbon-14 dioxide ("CO,) evolution from unilabeled glucose in lake water was highest at about 12°C, less but still appreciable at 4°C, and severely inhibited at 20°C. Oxygen effects. Mikell, Parker, and Simmons (1983) have shown that high dissolved oxygen levels simulating those of the sub-ice waters of southern Victoria Land lakes severely inhibit the growth and metabolism of planktonic bacteria from the ANTARCTIC JOURNAL
oxygen saturated oligotrophic alpine Mountain Lake, Cues County, Virginia. All evidence points to an intracellular site of oxygen or oxygen byproduct inhibition. These results are in striking contrast to similar experiments conducted on the planktonic bacterial communities of the antarctic lakes where bacterial growth and metabolism were not inhibited and sometimes apparently stimulated by high dissolved oxygen levels (Mike!! and Parker in preparation). Phosphorus limitations. In situ phosphorus-33-labeled phosphate (33PO4 3) uptake rates by plankton have been conducted in the four lakes during three austral summers (Seaburg et al. in preparation.) A total of 40 tracer and 20 nontracer level experiments showed that, while turnover times for natural phosphate (PO4 3) pools were much longer than for temperate latitude lakes, phosphorus probably is a major limiting nutrient for plankton growth and productivity. Notable exceptions are at lake depths where light is severely limiting, phosphorus has accumulated, or plankton densities are very low. Stromatolites. A unique feature of at least five southern Victoria Land lakes are the benthic bluegreen algal-bacterial-diatomaceous mats which have formed modern stromatolites, representing the only cold freshwater stromatolites presently known on Earth. Various stromatolite types occur in Lakes Bonney(B), Chad(C), Fryxell(F), Hoare(H), and Vanda(V) ranging to various depths. These include columnar liftoff (B, C, F, H), aerobic prostrate (B, C, F, H, V), anaerobic prostrate (F, H, V), and pinnacle mats (B, V). Other types of mats, such as floating, frozen in ice, and moat mats are ephemeral and do not form stromatolites. Wharton and others (in press) have presented details of the mat distribution, stratigraphic features, and algal species composition and have discussed the more important variables influencing their growth and form. Recently we have begun to examine the lipids extracted from select stromatolites, including free fatty acids, fatty acid triglycerides, hydrocarbons, sterols, and steroids (Orcutt and Parker, unpublished). The undegraded, excellent preservation of these lipid components with increasing depth of select stromatolitic cores from these lakes reinforce the findings of Simmons and others (1983) that chlorophyll and adenosine triphosphate were very stable in antarctic lake sediments in contrast to temperate lake sediments. From our preliminary survey of the lipids it has become clear that the major groups of micro-organisms occurring in the stromatolitic mats and cores (e.g., diatoms, bluegreen algae and bacteria, yeasts) reflect the lipid composition. Examination of the lipids from deeper cores should contribute significantly to an understanding of biochemical diagenesis of cold freshwater stromatolites and possibly the rates and pathways of carbon cycling within these lakes.
1983 REVIEW
References Cathey, D. D., C. M. Simmons, Jr., B. C. Parker, W. H. Yongue, and M. R. VanBrunt. 1982. Protozoan colonization of artificial substrates in two Antarctic lakes. Transactions of the American Microscopial Society, 101(4), 353-367. Kaspar, M., C. M. Simmons, Jr., B. C. Parker, K. C. Seaburg, R. A. Wharton, Jr., and R. 1. L. Smith. 1982. A species of Bryum Hedw. from Lake Vanda, Antarctica. The Bryologist, 85(4), 424-430. Love, F. C., C. M. Simmons, Jr., R. A. Wharton, Jr., and B. C. Parker. 1982. Methods for melting dive holes in thick ice and vibracoring beneath ice. Journal of Sedimentology and Petrology, 43, 644-647. Love, F. C., G. M. Simmons, Jr., R. A. Wharton, Jr., B. C. Parker, and K. C. Seaburg. 1983. Modern Conophyton-like algal mats discovered in Lake Vanda, Antarctica. Geomicrobiology Journal, 3(1), 33-48. Mike!!, A. T., and B. C. Parker. In preparation. Response of the heterotrophic community to in situ high dissolved oxygen in Lake Hoare, Antarctica, Applied and Environmental Microbiology. Mikell, A. T., B. C. Parker, and C. M. Simmons, Jr. 1983. Sensitivity of an oligotrophic lake planktonic bacterias community to oxygen stress. Applied and Environmental Microbiology, 46(3), 545-548. Orcutt, D., and B. C. Parker. Unpublished data. Lipids extracted and identified from modern stromatolites in Lakes Bonney and Hoare, using gas-liquid chromatography and mass spectroscopy. Parker, B. C., C. M. Simmons, Jr., M. Kaspar, A. Mikell, F. G. Love, K. C. Seaburg, and R. A. Wharton, Jr. 1982a. Physiological adaptations of biota in antarctic oasis lakes. Antarctic Journal of the U. S., 17(5), 191-193. Parker, B. C., G. M. Simmons, Jr., K. C. Seaburg, D. D. Cathey, and F. C. T. Allnutt. 1982b. Comparative ecology of plankton communities in seven Antarctic oasis lakes. Journal of Plankton Research, 4(2), 271-286. Parker, B. C., C. M. Simmons, Jr., R. A. Wharton, Jr., K. C. Seaburg, and F. C. Love. 1982c. Removal of organic and inorganic matter from Antarctic lakes by aerial escape of bluegrass algal mats. Journal of Phycology, 18, 72-78. Seaburg, K. C., M. Kaspar, and B. C. Parker. In press. Photosynthetic quantum efficiencies of phytoplankton from perennially ice covered Antarctic lakes. Journal of Phycology. Seaburg, K. C., and B. C. Parker. In press. Seasonal differences in the temperature ranges of growth of Virginia algae. Journal of Phycology. Seaburg, K. C., B. C. Parker, and C. M. Simmons, Jr. 1981. Temperature-growth responses of algal isolates from Antarctic oases. Journal of Phycology, 17, 353-360. Seaburg, K. G., B. C. Parker, C. M. Simmons, Jr., and R. A. Wharton, Jr. In preparation. Phosphorus—A major limiting nutrient for Antarctic dry valley lakes. Polar Biology. Simmons, C. M., Jr., R. A. Wharton, Jr., B. C. Parker, and D. Anderson. 1983. Chlorophyll and adenosine triphosphate levels in Antarctic and temperate lake sediments. Microbial Ecology, 9, 123-135. Wharton, R. A., Jr., B. C. Parker, and C. M Simmons, Jr. In press. Distribution, species composition, and morphology of algal mats (stromatolites) in Antarctic dry valley lakes. Phycologia.
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