A framework for monitoring indicators of ecological sustainability in tropical forestry

Certifying ecologically acceptable forest management requires monitoring forest conditions and the environmental impacts of management activities. Through adaptive management, assessments that reveal excessive environmental impacts require revision of the management plan so that the ecological functions and attributes of forest ecosystems are maintained within acceptable limits. But how are these acceptable limits determined? And how can 'normal' or 'natural' conditions be defined when these are temporally or spatially variable. To determine the desired biological state of a forest indicator baseline values, together with some measure of variability under natural conditions, are needed. A useful Ecological Criteria and Indicator set should, therefore, provide objective standards for evaluation, and these standards should account for spatial and temporal variation in indicator states as well as resilience to anthropogenic disturbance. A framework is presented, within which the standards for assessing ecologically sustainable forest management might be defined. The published literature is drawn upon to determine the responses of selected indicators to natural and anthropogenic disturbances. Using these values we can begin to predict expected ecological conditions of a sustainably managed forest given information on forest type, disturbance intensity and time since disturbance.