Watershed Restoration: Principles and Practices

Chapter 4: Conceptual Roles of Biological Integrity and Diversity

P. L. Angermeier

doi: https://doi.org/10.47886/9781888569049.ch4

Ecosystems are valuable to society for many reasons. Some value stems from our consumptive uses, such as water supply, agricultural production, or hunting. But a major share of the value—an underestimated share—stems from benefits that are not consumed directly, such as maintenance of life-supporting conditions (including clean air and water), aesthetics, and most recreation. Much of the perceived value of ecosystems is linked directly to a broad array of biological elements, including genes, species, communities of organisms, and landscapes. These elements can be grouped into three categories: taxonomic, genetic, and ecological (Table 4.1). They have evolved through and are maintained by a broad array of natural processes, including mutation, speciation, predation, competition, and disturbance. Human uses of ecosystems can cause direct loss of biotic elements through overconsumption or indirect loss through alteration of key processes.