Tracking Ecosystem Shifts, from Microbes to Mammals, with Environmental DNA
Anni Djurhuus, University of South Florida
Global change in climate, environments, and shifts in biodiversity distribution necessitate assessments to provide a baseline measure to gauge undergoing changes. However, cross trophic level assessments of biodiversity are rarely conducted, and the simultaneous biodiversity fluxes from microorganisms to macro-organisms over temporal scales are non-existing but imperative to understand the total community impact. The genetic trace of an organism in a given environment, referred to as environmental DNA (eDNA), allows for the detection of that organism within a given environment. However, no research has yet been done comparing eDNA data across trophic levels.
We present research, using metabarcoding of eDNA, to detect the biological composition and diversity of communities across multiple trophic levels (microorganisms, phytoplankton, invertebrates, and vertebrates). This study spanned two years and samples are collected from Monterey Bay, California and the Florida Keys national marine sanctuaries. Monterey Bay and the Florida Keys represent contrasting environments where we found very different patterns in biodiversity. The biodiversity at Monterey Bay was highly affected by the upwelling that occurs in the region and the Florida Keys biodiversity was more affected by local processes such as precipitation and run-off. Seasonal shifts have previously been observed in individual organisms but not across several domains of life co-currently over seasons and years. This demonstrates a highly promising observation method to detect ecosystem shifts from microbes to mammals using non-invasive sampling techniques.