Regional-Scale Patterns

Abstract

In this chapter we emphasize that regional processes shape local diversity and that the realized diversity represents the interplay of local and regional processes. Local diversity is predicted by the number of species in the regional species pool. This species pool is a result of speciation, extinction and migration among regions. At smaller scales, environmental disturbance, stochastic extinctions, productivity, predation, competition, dispersal and facilitation modulate diversity patterns limited by the size of the regional species pool. Using examples from different biogeographic regions, we illustrate how community variability varies across spatial scales and how the balance between local and regional environmental variability determines the structure of benthic assemblages.