Current Research
Alteration of community assembly & energy flow along the stream to lake continuum
Nutrient drivers of phytoplankton productivity in freshwater are well understood. Despite this, cyanobacteria bloom events remain challenging to predict because we do not fully understand how climate change processes influence the mechanisms underlying these relationships at lake and watershed scales. Our work investigates the role of extreme hydrologic events in determining algal community assembly and energy transfer (carbon flux) along a stream to eutrophic lake continuum. In collaboration with Pablo E. Gutiérrez-Fonseca (UVM RSENR), we are investigating the influence of disturbance sequence (drought or heat wave followed by flood or vice versa) and intensity on the lag time between community turnover in stream and pelagic biota, and changes in energy flow along the stream to lake continuum. This work is funded by USGS award #G24AC00122 to AMM & PEG.
MS student: Jo Delahunt
A disturbance phenology for phytoplankton communities and ecosystem function
Anthropogenic disturbance is not only altering ecosystem function but shifting the amplitude of fluctuation in aquatic ecosystems. Lakes phytoplankton communities are sentinels of ecological change, responding to disturbance and shaping biogeochemical cycles through fluctuation in their biomass, primary productivity, and functional traits. Although algae generally have a doubling time of hours to days, traits such as dormancy and alternative metabolic strategies allow persistence of populations across annual to multi-decadal time scales. This project aims to describe a disturbance phenology framework for algal community assembly that is scalable across space and time in order to predict feedbacks and threshold shifts in lake ecosystem function. This work is funded by NSF DEB CAREER award #2144197.
PhD students: Rachel Cray & Edouard Rugema
On Thin Ice: Future phytoplankton phenology and ecosystem function
Lakes around the world face rapidly warming temperatures coupled with shorter winters, which affects ice cover, and phytoplankton dynamics. We predict that the gradual loss of winter ice and snow cover will dramatically shape lake physical characteristics, which sets the template for phytoplankton species interactions and competitive outcomes. As a lake’s thermal regime shifts, we expect there will be major changes to phytoplankton community interactions and competition, which will alter succession and cyanobacteria bloom patterns. Our work addresses foundational ecological questions related to community diversity and assembly, placed in the context of rapidly changing winter conditions. Collaborators: Rebecca North (U of Missouri), Meredith Holgerson (Cornell), Bella Oleksy (U of Colorado Boulder, and Dave Richardson (SUNY New Paltz). Funded by NSF Macrosystems award #2306896.
Postdoctoral Researcher: Anila P. Ajayan, PhD
