Freshwater lakes around the world provide essential ecological and human benefits that range from aquatic habitat to sport and commercial fisheries to safe and reliable drinking water. The goal of the North Temperate Lakes (NTL) Long-Term Ecological Research Program is to understand how and why lakes change over time and to determine the consequences of these changes for these and other basic services. The research focuses on two sets of lakes and their surrounding landscapes. One set lies in the rural, forested, and tourist-dominated Northern Highland Lake District in northern Wisconsin and the other lies in the agricultural and urban landscape around Madison, Wisconsin's capitol. Studies of these contrasting settings provide insights into how individual lakes and groups of lakes across landscapes and regions are affected by phenomena such as shifting climate conditions, large storm events, invasive species, harmful algal blooms, urbanization, and changes in environmental policies. The project implements a number of different approaches to collect data over long time periods and to analyze these long-term observations. Results improve understanding of ecological change in lake districts that is important to anyone concerned with the future of a particular region, its freshwater resources, and the welfare of its residents. Results are also integrated into multiple educational and training activities. The NTL program is committed to supporting diversity in science, and to outreach efforts that communicate scientific findings and expertise to broad audiences, informing individuals, non-governmental organizations, academics, and local, state and federal agencies.
The project will address the overarching question of how biophysical setting, climate, and land use and cover interact to shape lake dynamics and organization in the past, present and future. Activities will be organized in thematic areas that involve (1) documenting, describing, and interpreting long term change in lakes and lake districts; (2) exploring how past and potential future climate conditions influence lake physical, chemical, and biological processes; (3) understanding how and why long-term changes vary spatially within and among lakes; and (4) examining how lakes and lake districts respond to sudden changes, extreme events, or interacting drivers. The work informs and is informed by concepts and models from landscape ecology, disturbance ecology, and multiple causation. Questions will be addressed across a range of scales and topics, including within-lake changes in thermal regime and fish habitat in response to climate, abundance-impact relationships for aquatic invasive species among lakes; watershed organic carbon and phosphorus dynamics, regional water clarity trends, and many others. Research approaches include generating and analyzing long-term observations, experiments, comparative studies of multiple lakes, and diverse modeling and statistical tools. The research group comprises an interdisciplinary team with expertise in biogeochemistry, climatology, paleolimnology, demography, ecology (landscape, ecosystem, community, population, and paleo- ecology), economics, education and outreach, hydrodynamics, hydrology, information management, and microbiology. The multi-scale, multi-faceted NTL research program is designed to detect patterns of long-term change, evaluate and advance concepts to understand causes and consequences of these changes, and build forward-looking models and hypotheses that will be tested using future long-term observations.
