January 20 @ 1:30 pm – 2:30 pm at LBNL, Building 66 Auditorium
Philippe Van Cappellen, Canada Excellence Research Chair, Ecohydrology, University of Waterloo
Hosted by: Bhavna Arora
About the Speaker
This presentation is now available EESA’s YouTube Channel. Click here to watch the presentation.
Philippe Van Cappellen joined the University of Waterloo as the Canada Excellence Research Chair in Ecohydrology on June 1, 2011. He was previously the Georgia Research Alliance Eminent Scholar in Global Environmental Studies at Georgia Institute of Technology in Atlanta, USA, and Professor of Geochemistry at Utrecht University in the Netherlands. Van Cappellen’s research focusses on the biogeochemistry of soils, rivers, lakes, and coastal environments, the cycles of water, carbon, nutrients and metals, geomicrobiology, geochemical tracers, ecohydrology, global change, and environmental modeling.
The damming of rivers represents one of the major anthropogenic disturbances of the natural cycles of water and nutrient elements on the continents. The associated changes in the environmental flows of nutrients have far-reaching consequences, from individual ecosystems to the global biosphere. While dam reservoirs usually act as sinks of macronutrients, their effects on riverine fluxes and chemical speciation differ markedly from one nutrient element to another. Dams thus fundamentally alter nutrient limitation patterns, trophic conditions and water quality in river ecosystems and receiving water bodies, including lakes, floodplains, wetlands and coastal marine areas. Here, I will present a knowledge-based upscaling framework, which integrates available data on elemental budgets for individual reservoirs, mechanistic models of nutrient cycling in surface water bodies, and a stochastic analysis of model outcomes. The approach enables us to simulate temporal changes in nutrient elimination by damming in all the major river basins of the world. I will illustrate the approach by presenting spatially explicit estimations of phosphorus (P) retention in dam reservoirs for the period 1970-2050. If time permits, I will also discuss our results for nitrogen (N) and organic carbon.