An argument for ecosystem level monitoring

One objective of environmental monitoring programs is documentation of qualitative and quantitative environmental changes in response to external stresses, including chemical contamination. Chemical contaminant, biological, and ecological measurements have been used as environmental monitors. Contaminant monitoring allows estimation of exposures; biological and ecological monitoring allow estimation of uptake and effects.Measurements of ecosystem homeostasis such as nutrient cycling processes have been shown to be good ecosystem level monitors. The rate of dissolved nutrient loss from ecosystems has been conclusively shown to increase as a function of chemical contamination until a new equilibrium is reached, the pollutant input has become negligible, or until nutrient pools have been depleted. Consequently, nutrient pools in environmental strata and in biota are altered and eventually depleted by chemical stress.The use of nutrient cycling to determine sensitive responses to and long-term changes for chemical contamination is an essential monitoring strategy for environmental management and compliance purposes. Measurements of export (rapid response) and pools (long-term consequences) are within current technology, are cost-effective, and allow rapid implementation of remedial measures or environmental controls.Paper presented at a Symposium held on 20–21 April 1982, in Edmonton, Alberta, Canada.