US EPA

4132 

Book/Book Chapter 

Introduction: What are ecosystem services? 

Daily, GC 

1997 

Island Press 

Washington, DC 

Societal Dependence on Natural Ecosystems 

1-10 

English 

The purpose of this book is to characterize the ways in which earth's natural ecosystems confer benefits on humanity, to make a preliminary assessment of their value, and to report this in a manner widely accessible to an educated audience. An ecosystem is the set of organisms living in an area, their physical environment, and the interactions between them. Although the distinction between "natural" and "human-dominated" ecosystems is becoming increasingly blurred, our focus is on the natural end of the spectrum, for three related reasons. First, the goods and services flowing from natural ecosystems are greatly undervalued by society. For the most part, the benefits those ecosystems provide are not traded in formal markets and do not send price signals of changes in their supply or condition. This is a major factor driving their conversion to human-dominated systems (e.g., agricultural lands), whose economic value is expressed, at least in part, in standard currency. Second, anthropogenic disruptions of natural ecosystems-such as alteration of the gaseous composition of the atmosphere, introduction and establishment of exotic species, and extinction of native species-are difficult or impossible to reverse on any time scale of relevance to society. Finally, if current trends continue, humanity will dramatically alter or destroy virtually all of earth's remaining natural ecosystems within a few decades. 

Daily, GC 

9781559634755