The Regional Impacts of Climate Change  Other reports in this
collection  4.3. Vulnerabilities and Potential Impacts for Key
Sectors  4.3.1. Ecosystems  Summary: In responding to climate
change, Australasia's biota may face a greater rate of long-term
change than ever before. They also must respond in a highly
altered landscape fragmented by urban and agricultural
development. There is ample evidence for significant potential
impacts. Alterations in soil characteristics, water and nutrient
cycling, plant productivity, species interactions (competition,
predation, parasitism, etc.), and composition and function of
ecosystems are highly likely responses to increases in
atmospheric CO2 concentration and temperature and to shifts in
rainfall regimes. These changes would be exacerbated by any
increases in fire occurrence and insect outbreaks.  Aquatic
systems will be affected by the disproportionately large
responses in runoff, riverflow and associated nutrients, wastes
and sediments that are likely from changes i