LTREB: Collaborative Research: What Controls Long-term Changes in Freshwater Microbial Community Composition?

University Of Maryland Center For Environmental Sciences, Cambridge MD

Investigators

Abstract

Recent developments in DNA sequencing and molecular technologies have revolutionized the study of microorganisms, revealing their identities and genetic potential, and spawning new ecological concepts in microbial biodiversity. Spatial and temporal patterns in microbial species and their roles in natural ecosystems are controlled by their dispersal attributes (e.g., whether by wind or water) and local growth conditions, but the relative importance of these factors is unknown. This research will characterize these two fundamental controls on the distribution of microbes in Arctic lakes, streams and soils, and will reveal how seasonal, annual and long-term shifts in the populations of microbial species relate to the rapid climatic changes that are occurring in this region. The complex nature of microbial biodiversity is important for understanding human health and disease, and for understanding the consequences of our warming world. Bacteria and other microbes ultimately control the production of carbon dioxide and methane, potent greenhouse gasses, in all ecosystems. In the Arctic there are currently low but rapidly increasing temperatures, thawing permafrost, and much accumulated organic matter all creating a situation ripe for increased bacterial respiration (conversion of organic matter to carbon dioxide). These collective factors could greatly alter regional and global carbon budgets, and hence feedback to further climate changes. This project will also contribute to teaching and outreach through the NSF Research Experience for Teachers program, the LTER-Schoolyard (K-12) program, and other field-based courses and mentoring programs.