The vulnerability of ecosystem trophic dynamics to anthropogenically induced environmental change: A comparative approach

The chapter, "The vulnerability of ecosystem trophic dynamics to anthropogenically induced environmental change: A comparative approach" was written by the listed authors including Jessica L. Clasen (Douglas College Faculty). The Ecological Dissertations in the Aquatic Sciences (Eco-DAS) symposia bring together 35-40 recent PhD recipients for one week in alternate years. Eco-DAS VIII was held in 2008. Eco-DAS is sponsored by the Center for Microbial Oceanography: Research and Education (C-MORE), the University of Hawai`i School of Ocean and Earth Science and Technology (SOEST) and its Department of Oceanography, and the Association for the Sciences of Limnology and Oceanography (ASLO). The Proceedings of Eco-DAS VIII includes nine chapters published in open access. <p>We employed a comparative approach to review the vulnerability of the trophic interactions within aquatic systems to global threats associated with anthropogenic activities. The goal of this chapter was to identify and characterize mechanisms by which human-mediated environmental threats may modulate trophic dynamics across aquatic ecosystems. Trophic dynamics include some of the most obvious and pervasive factors influencing ecosystems and were used as a metric because of their importance and commonality across all aquatic environments. Our use of trophic dynamics proved to be insightful, illustrating that the flow of energy through aquatic food webs will be (or already has been) altered by invasive species, land-use change, nutrient loading, exposure to ultraviolet radiation, overharvesting, acidification, and increasing global temperatures. The response of trophic dynamics to these threats was often similar across oceans, estuaries, lakes, and rivers. This similarity proved to be interesting given the differences in both the level of concern expressed by scientists and the predicted variability in environment-specific responses. As the trophic interactions of an ecosystem are at the root of its function and structure, examining trophic dynamics could be an informative method for evaluating the response of aquatic environments to global threats. If future analyses validate the use of trophic dynamics as a metric, it is our hope that trophic dynamics can be used by scientists and politicians to mitigate the effects of human actions.