DIFFERENCES IN MICROBIAL COMMUNITY STRUCTURE BETWEEN THE RED RIVER AND WINNIPEG RIVER IN MANITOBA, CANADA

Microbes play a dynamic role in nutrient and carbon cycling within riverine ecosystems so it is vital to understand their ecology and distributions in light of anthropogenic influences, particularly in systems heavily impacted by eutrophication like the Lake Winnipeg watershed. The two main inputs to Lake Winnipeg are the Red River, dominated by agricultural land use, and the Winnipeg River, which is primarily forested. While 70% of the water entering Lake Winnipeg comes from the Winnipeg River, 70% of the excess phosphorous comes from the Red. In 2002 we initiated an ongoing microbial community monitoring program in collaboration with local First Nations to conduct repeat seasonal sampling at 20+ sites in the Lake Winnipeg watershed including the Red, Assiniboine, La Salle, Seine, Brokenhead, and Winnipeg Rivers. Using Oxford Nanopore shotgun metagenomic sequencing, we conducted metagenomic binning to reconstruct draft genomes for the most abundant taxa in these rivers. As in other large metagenomic surveys like the Genome Resolved Open Watersheds database, we found a core of common taxa across river systems, but distinct compositions in each river. Significant seasonal and interannual variability were evident as well, indicating that ongoing monitoring is needed. Going forward we aim to include additional environmental parameters to gain a more complete understanding of the factors leading to changes in microbial community structure in this watershed.

Presentation Preference: Poster

Primary Presenter: Maria Garcia, University of Manitoba (garcimds@myumanitoba.ca)

Authors:

Maria Garcia, University of Manitoba  (garcimds@myumanitoba.ca)

Debosmitha Sen, University of Manitoba  (send@myumanitoba.ca)

Eric Collins, University of Manitoba  (eric.collins@umanitoba.ca)