Monster Seminar JAM - Biological Recovery of Lakes from Acidification: Local and Regional
Dr. Shelley E. Arnott, Dept. of Biology, Queen's University.
Many of the worlds ecosystems have been altered by human activities, often resulting in severe environmental impacts, with declines in biodiversity frequently identified as one of the most serious repercussions. An important example is the loss of aquatic biodiversity resulting from regional acid deposition. Sulphur dioxide emissions from mining and smelting activities around Sudbury, Ontario caused the acidification of thousands of lakes and the local extirpation of many aquatic species. Legislative action has resulted in reduced emissions and improved water quality. Despite increases in lake pH, there has been limited evidence of biotic recovery. My research group has been investigating factors that control the re-establishment of zooplankton communities in lakes recovering from acidification in the Sudbury region. Field experiments show strong evidence that both biotic interactions and local environmental conditions act as barriers to recovery. In addition, we have found that regional factors such as the availability of colonists and additional large-scale stressors (climate change, invading species) influence recovery trajectories
Date and Time:
November 20, 2003,
11:00 am - 12:30 pm