provides a structure for knowledge that uses the common sense of biologists familiar with a regional biota, much as economic indices use common sense about economic conditions (e.g., Dow-Jones Average, Index of Leading Economic Indicators). Properly conceived and used, multimetric approaches based in sound biology are statistically rigorous (Fore et al., 1994). They provide a way to summarize complex information in a single quantitative expression while preserving information about each biological attribute. Properly selected measures of biological integrity can be used to determine whether life-support systems are degraded and identify the factors responsible for degradation. They may even be used to track the success of restoration programs.
If we are to stem biotic impoverishment and reverse environmental degradation, we must
Two disciplines of fundamental importance to human society, engineering and ecology, have expanded at unprecedented rates during the twentieth century. Most practitioners of one of these disciplines have only limited knowledge about the other, and fundamental conceptual differences have limited their interaction. Engineering developed to improve the lot of humans; most engineering incorporates only the chemical and physical dimensions of the natural world. The failure of engineering to recognize the importance of biological limits and connectivity within biological systems is matched by the failure of ecology to contribute to the resolution of important societal problems.
Engineers and ecologists fail to address the right problem at the right time. Engineers are accustomed to others defining problems for them to solve, or they propose inappropriate solutions to perceived problems. Ecologists spend too much time trying to understand problems before they take action. They may be incapable of contributing useful solutions because they get lost in the details of natural environmental variation.
Today societal realities compel both disciplines to improve their craft by