OPUS: Linking species traits, community change and environmental change across scales to forecast how animal declines impact ecosystem function

Human alteration of the environment has led to rapid declines in animal populations, particularly in freshwater habitats. When animals are lost, the important roles they play in ecosystems are also lost. Understanding the consequences of these biodiversity declines for the natural services they provide requires long-term data.

Freshwater mussels are a good example. Few people know that they were once abundant and are now rare. They feed by filtering algae and other material from the water.

This “biofiltration” helps with nutrient cycling and provides ecosystem services such as improved water quality for humans. This project will synthesize 30-years of data on mussel distribution, abundance, and community composition across rivers in the Ouachita Highlands of Oklahoma and Arkansas. Information on species biological traits, such as temperature tolerance, body size, and filtration rates, will be used to estimate how mussels help the environment and benefit humans.

This will be combined with climate change projections to predict how these functions may change in the future. Products from this project will include journal articles, a book on mussel ecology, and an educational web site and poster on the mussels of Oklahoma.

Long-term data are needed to understand how Anthropocene declines in animal biodiversity and abundance affects the ecosystem functions they perform, which are a product of interactions among species’ functional traits, the environment, and community composition. This project will synthesize 30-years of data on mussel traits (thermal tolerance, adult body size, life history strategy), mussel community structure (species richness, abundance, and biomass from 8 rivers in one biogeographic region, the Ouachita Highlands), mussel community change, environmental gradients (temperature and flow), and ecosystem function (biofiltration and nutrient cycling and storage) to: (1) Estimate mussel contributions to ecosystem function across spatial scales (mussel bed, river, biogeographic region); (2) Determine how mussel losses and environmental change have altered these contributions, and how this is related to species functional traits; and (3) Use species traits and projections for future stream flows and temperatures derived from downscaled climate models to forecast how these contributions will change in the future. All data will be made publicly available in a web-based, permanent archive.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.