Cumulative impacts and environmental values

Abstract

The degradation, conversion, or loss of ecosystem functions is a ubiquitous outcome of human activities and socioeconomic development. Although mechanisms and pathways of change are complex and span many disciplines, the outcomes of development are often predictable and can result in a global decline in biological diversity as well as in the myriad of other ecosystem services that are the foundation for healthy economies and communities. Even ‘green’ development has associated environmental costs, and the alteration of climate will affect even the most pristine ecosystems as human development reaches formerly distant and undisturbed parts of the globe. While cumulative environmental impacts from natural resource development have been well studied, and there are numbers of environmental impact assessment processes in use, many are not living up to their potential and may in fact be the wrong processes for addressing cumulative impacts at regional scales. Over the long term, sustainable development of any environment will depend on a rigorous and defensible assessment of the resultant cumulative impacts if we are to understand, evaluate, limit, or mitigate projects that exceed the capacity of the local environment. In this Chapter, we examine a variety of approaches and tools used for assessing and managing cumulative impacts. We argue that to effectively anticipate and manage for cumulative impacts, we need cross-sector knowledge of past and proposed development, and the ability to plan at spatial scales appropriate to the environmental integrity of the region rather than the project.