The Use and Misuse of Neutral Landscape Models in Ecology

Abstract

Neutral landscape models (NLMs) were developed from percolation theory nearly a decade ago. Since then, the original random percolation maps have undergone adaptive radiation and NLMs now include a diverse array of spatially explicit models based on theoretical distributions derived from fractal geometry and spectral synthesis. The purpose of NLMs is to provide null models of landscape structure as a baseline for comparison with real landscape patterns, or for evaluating the effects of landscape structure on ecological processes. As the use of NLMs has expanded beyond the domain of theoretical landscape ecology to applications in other areas of ecology, there is an increased risk that NLMs will be used inappropriately, or that their function will be misunderstood or misinterpreted. NLMs are being subjected to the same general criticisms levied against null models in other areas of ecology. For this reason, we clarify the purpose of NLMs, review the contributions of NLMs to ecology, and evaluate the appropriate use of NLMs in ecological research. NLMs have already made several contributions to ecology: (I) development of spatial indices to describe landscape patterns; (2) prediction of critical thresholds in ecological phenomena; (3) definition of landscape connectivity; (4) development of species' perceptions of landscape structure; (5) provision of a general model of spatial complexity; and (6) determination of the ecological consequences of spatial heterogeneity. In the future, emphasis on NLMs should shift from theoretical development to application and model testing.