Spatial patterns

In this chapter, the discussion focuses on the spatial variation of species within urban environment. Studies on urban–rural gradients are discussed. These are studies along gradients of disturbance and environmental stress. The extreme heterogeneity of urban environments, where contrasting urban forms are juxtaposed, is recognized as an issue in drawing generalities. Despite this, some limited generalities in the patterns of species richness and density can be detected. The intermediate disturbance hypothesis is discussed and its limitations identified. Examples are presented from a number of taxa where different spatial distribution patterns are observed. There is also a brief consideration of r- and K-selected species and of urban avoiders and adaptors and how their distributions are affected by urban environments. While it is possible to make general statements regarding the distribution of biodiversity across an urban environment, considerable variations exist in terms of individual species.