Control Act Amendments 1972 and 1977 (33 U.S.C. 466 et. seq.). Endangered 

 Species Act of 1973 (16 U.S.C. 1531-1543), Clean Air Act of 1974 as Amended (42 

 U.S.C. 1 857 et. seq.). Federal Nonnuclear Energy Research and Development Act of 

 1974 (42 U.S.C. 5901-5915), Forest and Rangeland Renewable Resources Planning 

 Act of 1974 (16 U.S.C. 1601), National Forest Management Act of 1976(PL94-588), 

 Federal Land Policy and Management Act of 1976(43 U.S.C. 1701-1781), Soil and 

 Water Resources Conservation Act of 1977 (16 U.S.C. 2002), and the Surface 

 Mining Control and Reclamation Act of 1977 (30 U.S.C. 1201).'.6 



All of these mandates address the protection, inventory, conservation, 

 rehabilitation, or planning of the nation's environmental resources. Many of these 

 statutes represent the organic legislation of federal agencies such as the 

 Environmental Protection Agency, the Water Resources Council, the Council on 

 Environmental Quality, the Bureau of Land Management, and the Office of Surface 

 Mining, all of which contribute to habitat protection. For a compilation of relevant 

 federal laws the reader is referred to Ross^ (prior to 1972) and the U.S. Fish and 

 Wildlife Service.^ Most of the recent legislation is focused on species/ populations, 

 biological integrity, environmental values, or habitat, all of which may be dimensions 

 of habitat protection. Some important common elements of these laws are: 



• The objective projection, within the environmental impact assessment, of the 

 quantitative and qualitative changes in the physical, chemical, biological, and 

 social structures associated with those alternative ways of achieving the 

 proposed objective. The "goodness" or "badness" of each alternative is 

 determined by the decisionmaker(s) and is not made a part of the assessment. 



• The recognition-that man can exploit natural resources to a point where his life 

 support system may begin to break down. They also recognize and reaffirm the 

 NEPA goals that modern industrialized society must legally provide for the 

 maintenance, conservation, and/or rehabilitation of its basic life support 

 system, for both present and future generations. The environmental 

 assessment should determine the long-term as well as the short-term changes of 

 the alternatives and give particular attention to irreversible, unavoidable, and 

 unmitigatable impacts. 



• The capability to quantify the extent and status of natural resource 

 components, their functional interrelationships, and their susceptibility to 

 irreparable damage or loss. 



• The capability to accurately predict the effects on, or losses of, natural 

 resources resulting from man-induced changes. 



• A recognition of the interactions between physical, chemical, and biological 

 components and their relationship to environmental quality. Thus, to varying 

 degrees, an ecosystem approach to impact assessments is defined. 



None of the environmental laws or regulations which require impact assessment 

 prescribe a specific methodology to be used in the collection, compilation, analysis, 

 or evaluation of natural resource information. The common elements provide 

 general guidance in approaching the question of how to design an assessment 

 methodology and thus the role and requirements for data base development. These 

 legal mandates will evolve and become refined, and some new policies will be 

 added.'" A major opportunity for a common theme or approach to impact 

 assessments in the coming decade is related to the ecosystem concept. 



Technical Perspectives 



The ecosystem concept can be applied at both a conceptual and an operational 

 level in ecological assessments.^ The ecosystem represents the top of an operationally 

 definable hierarchy of levels of biological integration, followed by subsystems 

 (communities), system components (populations), and component elements 



11 



