Dr. Susan Ziegler
Canada Research Chair in Environmental Science
Coming to Canada from University of Arkansas, Fayetteville, Arkansas, USA
Studying the impact of nutrient enrichment on the biogeochemical function of watersheds spanning headwater streams to coastal ecosystems.
The research is revealing how nutrient enrichment, a globally significant form of environmental phenomenon, affects the ecological function of aquatic ecosystems in Canada.
When Too Much is a Bad Thing: Nutrient Enrichment in Canada’s Aquatic Ecosystems
A dead zone is an area of water too low in dissolved oxygen to sustain life, and there are at least 146 of them around the world. They range in size from small sections of coastal bays to large seabeds that span some 70,000 square kilometres. What is creating these dead zones? What is killing the fish and other living organisms? Clearly, a complex chain of events is to blame, but the final trigger is the nutrient enrichment caused by atmospheric deposition, agriculture and forestry practices, urban runoff, and sewage within the watersheds.
Dissolved organic matter (DOM) fuels microbial activity in the aquatic ecosystem, which in turn drives the biogeochemical processes — the cycling of critical elements within our environment. In her research as a Canada Research Chair, Susan Ziegler studies the effect of environmental change on nutrient and DOM cycling within the continuum from headwater streams to coastal marine ecosystems. By focusing on numerous streams within contrasting watersheds, she hopes to reveal the interrelated effects of nutrient enrichment and solar UV radiation on DOM biogeochemistry. She is also trying to link watershed processes to the biogeochemistry of coastal ecosystems.
Ziegler’s research program is influencing the fields of both aquatic biogeochemistry and global climate change by clarifying how environmental impacts within watersheds alter an ecologically and globally significant carbon reservoir. In the process, her program is creating educational and research opportunities for scientists engaged in multidisciplinary collaborative environmental science within and outside Atlantic Canada.