He also examine effects on wetlands, the Great Lakes, urban ecosystems, coastal waters and the open ocean. Over the past 35 years, he has advanced new analytical techniques, established and maintained long-term measurements and experiments, and developed a series of research and predictive models that simulate transformations of major chemical elements in forest vegetation, soil and surface waters in response to air pollution, climate and land disturbance. Beyond theory, he is interested in testing ‘in situ’ strategies to reverse the damaging effects of acid rain and mercury contamination and eutrophication. Current research includes using models, field experiments and measurements to examine: ecosystem effects of changing climate and acidic, nitrogen and mercury deposition; the effectiveness of “green” water infrastructure in storm water management; and ecosystem restoration.