Limnology and Aquatic Microbial Ecology of Byers Peninsula: A Main Freshwater Biodiversity Hotspot in Maritime Antarctica
Open Access
- 21 October 2019
- Vol. 11 (10), 201
- https://doi.org/10.3390/d11100201
Abstract
Here we present a comprehensive review of the diversity revealed by research in limnology and microbial ecology conducted in Byers Peninsula (Livingston Island, South Shetland Islands, Antarctica) during the last two decades. The site constitutes one of the largest ice-free areas within the Antarctic Peninsula region. Since it has a high level of environmental protection, it is less human-impacted compared to other sites within the South Shetland archipelago. The main investigations in Byers Peninsula focused on the physical and chemical limnology of the lakes, ponds, rivers, and wetlands, as well as on the structure of their planktonic and benthic microbial communities, and on the functional ecology of the microbial food webs. Lakes and ponds in Byers range along a productivity gradient that extends from the less productive lakes located upland to the eutrophic coastal lakes. Their planktonic assemblages include viruses, bacteria, a metabolically diverse community of protists (i.e., autotrophs, heterotrophs, and mixotrophs), and a few metazooplankton species. Most of the studies conducted in the site demonstrate the strong influence of the physical environment (i.e., temperature, availability of light, and water) and nutrient availability in structuring these microbial communities. However, top-down biotic processes may occur in summer, when predation by zooplankton can exert a strong influence on the abundance of protists, including flagellates and ciliated protozoa. As a consequence, bacterioplankton could be partly released from the grazing pressure exerted by these protists, and proliferates fueled by external nutrient subsidies from the lake’s catchment. As summer temperatures in this region are slightly above the melting point of water, biotic processes, such as those related to the productivity of lakes during ice-free periods, could become even more relevant as warming induced by climate change progresses. The limnological research carried out at the site proves that Byers Peninsula deserves special attention in the framework of the research in extreme environments. Together with nearby sites, such as Signy Island, Byers Peninsula comprises a featuring element of the Maritime Antarctic region that represents a benchmark area relative to the global distribution and diversity of aquatic microorganisms.Keywords
This publication has 81 references indexed in Scilit:
- Protection of Antarctic microbial communities – ‘out of sight, out of mind’Frontiers in Microbiology, 2015
- Insights into deglaciation of the largest ice-free area in the South Shetland Islands (Antarctica) from quantitative analysis of the drainage systemGeomorphology, 2014
- Maritime antarctic lakes as sentinels of climate changeInternational Journal of Design & Nature and Ecodynamic, 2012
- Virophage control of antarctic algal host–virus dynamicsProceedings of the National Academy of Sciences of the United States of America, 2011
- Biogeographical distribution and ecological ranges of benthic cyanobacteria in East Antarctic lakesFEMS Microbiology Ecology, 2006
- Planktonic microbial assemblages and the potential effects of metazooplankton predation on the food web of lakes from the maritime Antarctica and sub-Antarctic islandsReviews in Environmental Science and Bio/Technology, 2006
- Remarkable Diversity of Phototrophic Purple Bacteria in a Permanently Frozen Antarctic LakeApplied and Environmental Microbiology, 2003
- Benthic diatom flora of freshwater and saline lakes in the Larsemann Hills and Rauer Islands, East AntarcticaAntarctic Science, 2003
- The microbial composition of three limnologically disparate hypersaline Antarctic lakesFEMS Microbiology Letters, 2000
- Mixotrophic cryptophytes and their predators in the Dry Valley lakes of AntarcticaFreshwater Biology, 1999