Air Pollution Effects on the Diversity and Structure of Communities

As ecological units, biotic communities consist of aggregations of populations, interacting with other biotic and abiotic components of the ecosystem. Communities thus possess a set of emergent properties not understandable solely from inferences derived from the study of their constituent populations (O’Neill et al. 1986). Ideally then, delineating air pollution effects upon communities would involve measuring community attributes rather than attempting to infer community responses from individual plant or population measurements. However, the great body of air pollution effects literature is primarily based on individual organism responses, which provide little basis for inferring community response. Data limitations are especially acute when considering perennial plant communities, the focus of this chapter.