center for synthesis
and analysis of biodiversity

A centre created and developed by the FRB


Global Evaluation of the Impacts of Storms on freshwater Habitat and structure of phytoplankton Assemblages


Coordinator: Orlane Anneville - INRA (France)

Co-leaders: Jason Stockwell - University of Vermont (USA) ; Vijay Patel - US Geological Survey, Alaska (USA)

Postdoctoral fellow: Jonathan Doubek - University of Vermont (USA)

Participants: Gaël Dur - Shizuoka University (Japan); Sami Souissi - University of Lille 1 (France); François Schmitt - CNRS (France); Patrick Venail - Institut Forel, University of Geneva (Switzerland); Emily Nodine - University of Vermont (USA); Nico Salmaso - IASMA (Italie); Chih-hao Hsieh - National Taiwan University (Taiwan); Marc Lajeunesse - University of South Florida (USA); Rita Adrian - Leibniz-Institute of Freshwater Ecology and Inland Fisheries (Germany); Dietmar Straile - University of Konstanz (Germany); James Rusak - Dorset Environmental Science Centre (Canada); Aleksandra Lewandowska - Institute for Chemistry and Biology of the Marine Environment (Germany).

The GEISHA project brings together experts in theoretical ecology, aquatic ecology, limnology, biodiversity, plankton taxonomy impact of extreme events, climate change, statistical analysis, series-temporal meta-analysis, Bayesian approaches, turbulence and nonlinear variability analysis, and multivariate modeling.

GEISHA is cofinanced by the John Wesley Powell Center for analysis and synthesis, Colorado, USA.PowellCenter emblem 11

Learn more about the project on YouTube:



Future climate change is expected to cause more intense and frequent extreme weather events but we currently only have a basic understanding of how these events might alter freshwater phytoplankton communities. Because storms have strong impacts on thermal stratification and mixing dynamics of lakes, which in turn may influence niche availability and phytoplankton succession, we propose to study the impact of storms on the diversity, including taxonomic and functional composition, of freshwater phytoplankton communities. A thinking group (“Storm-blitz”) has been organized within the Global Lakes Ecological Observatory Network (GLEON) to address questions about the impacts of storms on phytoplankton community through sharing of long-term datasets and high-frequency data in lakes across the globe. GEISHA is built within the Storm-blitz framework and will benefit from the involvement and expertise of this group. The goals of GEISHA are to 1) create the time, space, and resources to work as a cohesive unit, 2) gather and standardize the long-term datasets, 3) perform meta-analyses to evaluate the sensitivity of aquatic ecosystems to extreme weather events, and 4) provide new frameworks to explore theoretical questions related to species diversity and succession in aquatic ecosystems.

Phytoplankton, storms, lake, disturbance, episodic events, thermal structure, warming, global change, biodiversity, species richness, taxonomic composition, community assembly, succession, time-series, meta-analysis, ecological observatory networks.


Photo credit: Lake Champain Basin Program 


February 2017

Jason Stockwell presented an overview of the GEISHA project at  the "Supporting Data-Intensive Freshwater and Marine Research: Integrating Informatics, Infrastructure, Databases and Open Science" session at the Association for the Sciences of Limnology and Oceanography (ASLO) meeting in Honolulu, Hawaii. The presentation can be seen below.



March 2017

The GEISHA project was presented to the Asian scientific community during the joint 17th International Symposium on River and Lake Environment and 3rd International Symposium on Aquatic Botany held in Kusatsu City, Shiga Prefecture, Japan, in March 2017. The poster introduced the project, its aim, the data source and the preliminary steps of the project

The poster can be downloaded here.


May 2017

GEISAH presented its conceptual model for how storms may impact the seasonal succession of phytoplankton by interacting with lake features to create conditions for which different traits of phytoplankton may be selected. The poster was presented at the 60th Annual Conference on Great Lakes Research (IAGLR) held in Detroit, Michigan.

The poster can be downloaded here.


September 2018

GEISHA was represented at the first meeting of IAGLR held outside of North America, in conjunction with the 5th European Symposium on Great Lakes. Orlane Anneville was co-organizer of this conference and presented a poster on behalf of the GEISHA group.

The poster can be downloaded here.


October 2018

Orlane Anneville presented their work in the CESAB session entitled « Dealing with heterogeneous data to improve our knowledge of biodiversity dynamics and ecosystem function: perspectives from synthesis projects » at the french ecological conference in Rennes, 2018.