Linking Land-Use Decision Making, Water Quality, and Lake Associations to Understand Human-Natural Feedbacks in Lake Catchments

People around the world benefit greatly from the critical services provided by freshwater lakes, such as drinking water, recreation, and fisheries. However, human activities can contribute to pollution and the growth of harmful algal blooms that degrade the lake waters that people rely upon and enjoy. This can generate a strong incentive for behavioral change. For example, citizen-driven lake associations often form in response to deteriorating water quality, and are becoming increasingly effective in driving changes in land management and policies that greatly improve lake environments. 

This project examines the linkages between land use, lake water quality, and local communities in three contrasting U.S. lake systems. Insights from these lake systems will in turn inform the study of human-natural system dynamics across thousands of other lakes throughout the northeastern and midwestern U.S. An understanding of these relationships and feedbacks will help inform the development of effective programs and policies to protect and enhance lake water quality.

This project investigates the nature and extent of linkages among human and natural systems in lake catchments. The project will develop a novel coupling framework that links process-based human and natural system models to trace the effects of land-use decisions on nutrient fluxes through lake ecosystems; represent how hydrological and limnological processes transform nutrient loads into changes in the water quality metrics valued by people; and determine how water quality changes feed back into human decision making by affecting property values and collective action by citizen groups. For three contrasting catchments in the northeastern and midwestern U.S., the project explores these linkages by deriving essential management variables that describe the critical drivers of human-natural system dynamics and the relationships between those drivers. These results provide an integrated foundation for a suite of statistical approaches that will be used to scale up and extrapolate the results to a diverse set of lake catchments representative of continental-scale gradients. These complementary activities will generate insight into broad-scale human-natural system dynamics, extending scientific understanding to enhance decision making to protect the valuable natural systems provided by lakes.