NSF Postdoctoral Fellowship in Biology FY 2010

Walters Annika, Seattle WA

Investigators

Abstract

This action funds an NSF Postdoctoral Research Fellowship for FY 2010. The fellowship supports a research and training plan entitled "Plankton phenology: how shifts at the species level propagate through a lake ecosystem." for Annika Walters. The host institution for this research is The University of Washington, and the sponsoring scientist is Daniel E. Schindler. Ecological dynamics are strongly influenced by climatic conditions. In lakes, warmer water temperatures can shift the timing of key physical processes, including spring ice-breakup and thermal stratification, which can affect the phenology of freshwater plankton species. The challenge is to understand how climate driven effects, for example shifts in the timing of peak abundance for a phytoplankton species, propagate through complex communities. Inter-specific interactions may cause species level impacts to quickly dampen out or to transmit broadly to have effects at the ecosystem level. This study utilizes a 48 year dataset of phytoplankton and zooplankton species abundances from Lake Washington, which has experienced a 1.4 °C increase in water temperature. The aim is to explore variation between species level and aggregate community and ecosystem level responses of plankton to warming. An understanding of how responses "scale up" can inform efforts to detect ecosystem impacts associated with climate change. Training goals include developing advanced skills in statistical analysis and modeling. The project will utilize a variety of time-series analysis techniques including dynamic linear models, multivariate autoregressive models, and spectral analysis. The study contributes to our understanding of climate change and provides opportunities for mentoring undergraduate students. The research supports long-term data collection at Lake Washington and the results will be presented at local lake association meetings, in addition to national scientific meetings and through publications.