Population, Community and Ecosystem Collapse and Recovery: Lessons Learned and Remaining Challenges For The Future Of Ecosystem Management
Wednesday, August 7, 2013: 1:30 PM-5:00 PM
101D, Minneapolis Convention Center
Andrea S. Downing
Andrea S. Downing
Increasing human population and its needs for food, housing, and energy, put ecosystems worldwide under escalating pressures, resulting in damaged ecosystems, disturbing declines in vital natural resources, and an alarming and continuous loss of biodiversity. Many ecosystems are beyond disturbed and have collapsed, i.e. significantly changed their structure, functioning, and, with it, the services they provide for people. For instance, an increasing proportion of fisheries worldwide is either fully- or over- exploited. Agricultural activities resulting in habitat destruction and high nutrient and chemical input into the environment have significantly reduced soil and water quality. Populations of many species around the globe are threatened by the environmental alterations that are a consequence of the changing climate. Understanding the drivers of this change is the first step in the process of recovery. Populations, communities and ecosystems have a capacity to withstand certain pressures that allows them to recover close to their previous state. Many biotic and abiotic factors play important roles in restoring system structure and functioning after disturbances. Ecological factors such as a species’ life-history, trophic position and strength of population regulation govern the population growth rate, which in combination with landscape or environmental factors may determine the population recovery potential.
More often, however, systems may never fully recover to their previous state, due to many indirect effects of a specific disturbance and interactions present in the system. Systems may even switch into an alternative stable state, thus seriously compromising recovery to the desired state. In this session, we present examples of population, community and ecosystem key features and processes in preserving or compromising desired system states and in determining their potential for recovery. The speakers presenting cover ongoing findings in empirical and theoretical research.