Ecological effects of pollution and disturbance

The broad theme of my research is the effects of "natural" and "anthropogenic" stressors on the structure and function of ecosystems. This work is placed within a broader context in my book: Environmental Ecology. The Impacts of Pollution and Other Stresses on Ecosystem Structure and Function. Second Edition. (Academic Press, 1995).

A longer-term aim of this research is to describe convergent patterns of ecological changes (usually representing degradation) that occur when ecosystems are stressed either: (1) chronically for a longer period of time, for example by toxic chemicals or climate; or (2) acutely for a shorter period of time, for example by episodic events of chemical pollution or physical disturbance.  

My most central research activity has examined the actual or potential changes of biodiversity values, site quality, and carbon storage associated with forest harvesting, silvicultural use of herbicides, and conversions of natural forests into intensively managed plantations. Component studies related to the ecological effects of forestry have included the following:

 (1) phytosociological changes occurring during secondary succession after clear-cutting, herbicide spraying, and plantation establishment.

 (2) temporal changes in standing crops of biomass, carbon, and macronutrients in above-ground vegetation, forest floor, and soil during forestry-related secondary succession.

 (3) potential implications for site fertility and acidification of the large nutrient and biomass removals that occur during forest harvesting.

 (4) effects on the abundance and species richness of animal wild life associated with physical and phytosociological changes in habitat caused by forestry activities.

 (5) the net flux of nutrients and other chemicals from watersheds variously influenced by forest, bog, and anthropogenic land-uses.

 (6) the autecology of plant species prominent in various stages of secondary succession, with particular emphasis on the relatively dynamic first two decades after disturbance associated with forestry harvesting or plantation establishment.

 (7) integrated studies of risks to the ecological integrity of Fundy National Park associated with its insularization by the extensive development of forestry plantations in its peripheral area.

Bill Freedman

George S. Campbell Professor of Biology 
Biology Department 

Education

• 1978, PhD, U. Toronto
• 1975, MSc, U. Toronto
• 1974, BSc (Hons), U. Toronto

Award

• 2006, Canadian Geographic Society: Canadian Environment Award, Gold Medal Level, in the category of Community Awards for Conservation

Publications

Dr. Freedman is widely published, with more than 92 referreed articles, 6 books, 5 edited volumes and numerous refereed and non-refereed conference and workshops and magazine articles

       
Website:  Faculty page

Email: Dr. Bill Freedman