HR: 11:26h
AN: H52C-05 INVITED    [Abstracts]
TI: Impacts of Climate Change on the Resilience of a Eutrophic Lake
AU: * Collins, D B
EM: dbcollins@wisc.edu
AF: Center for Sustainability and the Global Environment, Nelson Institute for Environmental Studies University of Wisconsin-Madison, 1710 University Ave, Madison, WI 53726, United States
AU: * Collins, D B
EM: dbcollins@wisc.edu
AF: Center for Limnology, Universty of Wisconsin-Madison, 680 North Park St, Madison, WI 53706, United States
AU: Carpenter, S R
EM: srcarpenter
AF: Center for Limnology, Universty of Wisconsin-Madison, 680 North Park St, Madison, WI 53706, United States
AU: Foley, J A
EM: jfoley@wisc.edu
AF: Center for Sustainability and the Global Environment, Nelson Institute for Environmental Studies University of Wisconsin-Madison, 1710 University Ave, Madison, WI 53726, United States
AU: Turner, M G
EM: turnermg@wisc.edu
AF: Department of Zoology, 430 Lincoln Dr, Madison, WI 53706, United States
AB: Phosphorus-limited lakes are believed to exhibit two meta-stable states: one characterized by low levels of phosphorus (P) and algae in the water column, and the other by high levels of P and turbid, eutrophic conditions. While brief spikes in P-loading from the watershed may cause the lake to shift from clear to turbid conditions, the turbid conditions may sustain themselves even after the loading drops by switching on recycling of P from the sediments. There are thus thresholds associated with lake P levels separating clear from turbid states, and associated with these states is a degree of resilience to environmental variability. In Wisconsin's seasonally eutrophic Lake Mendota, the long-term driver of lake quality is agricultural activity in the watershed, through manure and fertilizer application. This supply is mediated by the hydrological fluxes imposed by the prevailing climate. Lake Mendota's climate is expected to shift the balance of precipitation from snow towards rainfall, advance the onset of snowmelt and soil thaw, and lead to more variable summer precipitation, with concomitant effects on runoff and P loading. Using a distributed ecohydrological model of P fate and transport, we explore how scenarios of future climate change may affect the thresholds and resilience of Lake Mendota's trophic states to agricultural practices in the watershed.
DE: 0438 Diel, seasonal, and annual cycles (4227)
DE: 0439 Ecosystems, structure and dynamics (4815)
DE: 1813 Eco-hydrology
DE: 1871 Surface water quality
DE: 3305 Climate change and variability (1616, 1635, 3309, 4215, 4513)
SC: Hydrology [H]
MN: 2007 Fall Meeting