In the face of such complexity and the sometimes fierce conflict that attends it, managers need the best available information and tools. This report responds to a request to the National Research Council from the Department of Defense (DOD), which recognized that many of the lands that it owns or controls have potentially high value for the protection and maintenance of biodiversity. The primary purposes for which these DOD lands are managed requires that they be held in relatively large blocks and that they not be developed for commercial or residential uses. Although the military uses affect natural conditions, often much of the lands remain relatively free of major impacts on biodiversity. The Committee on Noneconomic and Economic Value of Biodiversity in the Board on Biology of the National Research Council's Commission on Life Sciences was charged with examining "how current scientific knowledge about the economic and noneconomic value of biodiversity can best be applied in the management of biological resources" (see appendix A, "Statement of Task"). This report reviews current understanding of the value of biodiversity and the methods that have been developed to assess that value in particular circumstances.
Although not denying that improved methods of valuation can aid decision-making, the committee and its report have focused on a more fundamental challenge. Specifically, important differences in opinion about decisions regarding biodiversity are likely to arise from differences in the ethical frameworks that people use to value biodiversity. The most precise economic analysis showing that a housing subdivision will generate greater economic benefit for society than the protection of a nature reserve will hold relatively little sway over the views of a person who believes that it is morally wrong to cause the extinction of a species that is found only in that nature reserve. As much as managers might like to simplify decision-making processes to a straightforward assessment of economic costs and benefits, the reality of the most important decisions that our society faces is far more complex. Wise decisions regarding social goods are made by weighing a variety of legitimate measures of importance or value.
This report differs from many recent ones that have focused solely on measures of the economic value of biodiversity in that it seeks to embrace the range of value frameworks that legitimately can be used to determine the merits of alternative courses of action regarding biodiversity. Recognizing that improved methods can enhance the process of decision-making within any framework for assigning value, we also provide a summary of state-of-the-art methods for establishing value. But we focus even greater attention on methods for weighing input from stakeholders with different frameworks for determining the value of different actions to yield sound resource-management decisions.
The wide range in the kinds of values that people attribute to maintaining biodiversity and in the basic philosophies that lie behind these values led to the committee's conclusion that the processes making decisions involving biodiversity are of greater importance than the techniques that assign values to any one of the philosophical postures. Choosing the appropriate decision process has two