Dr. Dorota Porazinska
The most recent projects are focused on testing the theory of community assembly and address the role of both deterministic (e.g., biogeochemical soil properties, diversity of plants and soil microbes, and traits of species) as well as stochastic (e.g., species pool size and history of species arrival) factors. To test these factors, we conduct observational and experimental studies across environmental gradients in high alpine and polar ecosystems. For example, at the alpine site at the Niwot Ridge of the Colorado Rocky Mountains, we use a natural gradient of plant community complexity (from bare to vegetated soils) to examine how nematode communities assemble and how they affect C and N sequestration. In Antarctica, we use microbial communities of cryoconite holes of the Dry Valleys’ Glaciers to examine how these communities form and function in relation to the characteristics of the Dry Valleys’ landscape. In all studies, we rely on DNA metagenomic sequencing for community analyses and incorporate a variety of biogeochemical measures.
Climate-warming driven changes in snow cover at the Niwot Ridge lead to progressive migration of plants into talus soils creating a gradient of terrestrial environments ranging from bare ground to increasingly vegetated. We use this gradient to study early successional assembly of soil communities. Photo taken August 20, 2015.