Grantee Research Project Results
2007 Progress Report: Eutrophication Thresholds – Assessment, Mitigation, and Resilience in Landscapes and Lakes
EPA Grant Number: R832445Title: Eutrophication Thresholds – Assessment, Mitigation, and Resilience in Landscapes and Lakes
Investigators: Carpenter, Stephen R. , Foley, Jonathan A. , Turner, Monica G.
Institution: University of Wisconsin - Madison
EPA Project Officer: Packard, Benjamin H
Project Period: September 1, 2005 through June 30, 2007 (Extended to August 31, 2008)
Project Period Covered by this Report: July 1, 2006 through June 30,2007
Project Amount: $299,999
RFA: Exploratory Research: Understanding Ecological Thresholds In Aquatic Systems Through Retrospective Analysis (2004) RFA Text | Recipients Lists
Research Category: Aquatic Ecosystems , Water
Objective:
Eutrophication, a persistent environmental problem characterized by turbid water, toxic algae, fish kills, waterborne disease, and loss of ecosystem services, may be related to important thresholds in the phosphorus (P) cycle. We will address two main questions: (1) what thresholds in the transport and cycling of P in linked terrestrial-aquatic ecosystems cause lakes to switch between clear-water and eutrophic states? (2) How can thresholds for transport and recycling of P be manipulated to mitigate eutrophication, or increase resilience of clear-water lakes against eutrophication? The research will conduct a retrospective analysis of the Yahara watershed and its major lakes (near Madison, Wisconsin), using a substantial historical database of land characteristics and limnology. Changes in this watershed are emblematic of those in many agricultural, urbanizing regions of the United States.
Progress Summary:
We published two theoretical papers. These show the conditions under which changes in variance can provide advance warning of regime shifts in ecosystems subject to input of pollutants.
We have completed the component of the project for modeling P in Lake Mendota. This involved completing the last 10 years of P budget calculations, leading to a total of 30 years of data, and then writing computer programs for Bayesian analysis of the lake threshold model using these data. A manuscript based on the results is presently in review.
We hired a postdoc, Dr. Daniel Collins (Ph.D. MIT 2006) to conduct the watershed modeling described in the proposal. He started work in August 2006.
Since hiring Collins, we have made progress on the watershed portion of the project. Collins has obtained the bulk of the necessary data, and selected the most suitable watershed model for the project, taking into consideration data availability, practical implementation and development, and ultimate communication of the results. Calibration of the model is underway in conjunction with sensitivity analyses of watershed response to climate change scenarios
Because of the time required to recruit Dr. Collins, we requested a cost-free extension which was approved by EPA. The focus of Dr. Collins's work in the next 6-12 months is to complete model calibration, conduct experiments on the roles of land use and climate change in the delivery of phosphorus to the Yahara Lake system, and publish the results.
Journal Articles on this Report : 2 Displayed | Download in RIS Format
| Other project views: | All 8 publications | 4 publications in selected types | All 4 journal articles |
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Brock WA, Carpenter SR. Variance as a leading indicator of regime shift in ecosystem services. Ecology and Society 2006;11(2):9. |
R832445 (2006) R832445 (2007) R832445 (Final) |
Exit Exit Exit |
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Carpenter SR, Brock WA. Rising variance: a leading indicator of ecological transition. Ecology Letters 2006;9(3):311-318. |
R832445 (2006) R832445 (2007) R832445 (Final) |
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Supplemental Keywords:
RFA, Ecosystem Protection/Environmental Exposure & Risk, Scientific Discipline, Air, Aquatic Ecosystem, Aquatic Ecosystems & Estuarine Research, Ecological Risk Assessment, Atmosphere, Air Pollution Effects, climate change, Environmental Monitoring, environmental history, lakes, water quality, anthropogenic impact, estuarine research, ecological thresholds, ecosystem indicators, modeling ecosystem change, ecosystem response, ecosystem stress, eutrophication, trophic interactions, land use, aquatic ecosystems, landscape changeProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.