prof. nick baer

I am interested in the functional responses of aquatic ecosystems to both anthropogenic and natural perturbations. As human derived impacts continue to alter the landscape, it becomes increasingly important to understand what organisms are present and how they are functioning in aquatic ecosystems. Resource managers are using measures of the aquatic community as signals of potential watershed and water quality impairments. The biotic community, in aquatic environments, provides distinct ecosystem services that are crucial in maintaining levels of primary production, leaf decomposition, nutrient cycling, and secondary production. These functional measurements can help us understand how the biotic community responds to disturbance events. Of particular interest are the foodweb dynamics that rely on terrestrially derived detritus, because they link the aquatic communities to terrestrial patterns and processes.

Lakes and their stream tributaries can have very different basil food resources due to forested stream systems, similar to the ones we see in NH, relying heavily on terrestrial derived leaf material as a major food resource due to low light penetration, and therefore a reduction in primary production such as algae. In contrast, lake and pond systems can have extensive phytoplankton communities which provide a food source to fuel the zooplankton and higher trophic level communities. These aquatic ecosystems can experience bottom-up controls on foodweb dynamics due to natural or human disturbances.

For example, nutrient enrichment from urban or agricultural runoff can alter the nutrient dynamics within streams causing elevated nutrients loadings. Also, road salt applications can cause steady increases in the ion concentrations in stream and lake systems. I am interested in how changes in water chemistry impact the different trophic levels in aquatic foodwebs in both streams and lakes. A desire to understand the complexity of the underlying mechanisms for these changes has motivated my research to date.