The McMurdo Dry Valleys is a polar desert ecosystem which composes the largest ice-free area in Antarctica, with the exception of perennially ice-covered lakes and ponds. The lakes in the valleys are the only landscape unit that support metabolic activity year-round. Recent increases in air temperature and solar radiation have led to a chain of disturbances altering the environmental conditions of these lakes. In this study, we test the impact of climatic disturbances on microbial communities in Lake Bonney, one of the lakes in the MDV. Through an integrated approach of combining field studies on natural communities in the lake (in situ) and laboratory experiments on algal isolates (ex situ), this study will attempt to understand how phytoplankton, eukaryal and bacterial communities respond to simulated disturbances. Results from the in situ experiments showed that the moat is a unique and stressful environment for under-ice communities and that under-ice shallow communities are highly sensitive to climatic disturbances. The ex situ experiments showed that certain phytoplankton species, like the chlorophytes, are more resistant to environmental alterations and thus will outcompete other phytoplankton species.