Are there fine-scale spatial patterns in community similarity among temporary freshwater pools?

One expects greater similarity between communities that are close together in space than between communities that are widely separated. This may be due to similarity in environmental conditions, short-range dispersal, or both processes together. We examined whether these mechanisms were important in determining the invertebrate communities in a set of temporary freshwater rockpools within an area of 800 m(2). Adjacent pools tended to share similar environmental characteristics (conductivity, pH, presence of predatory Salamandra salamandra L. larvae and amount of shade). Community dissimilarity was not strongly related to interpool distance. Environmental variables did not explain a significant amount of variation in community dissimilarity, although differences in pH and depth were the best predictors of community dissimilarity. We conclude that dispersal is not limiting in our study system.