Spatial Pattern and Ecosystem Function: Reflections on Current Knowledge and Future Directions

Relationships between spatial patterns and ecosystem function are briefly reviewed with regard to the current state of the science and its application and some important challenges. Ecosystem functions that are affected by heterogeneity include maintenance of species diversity (habitat) as well as material and energy cycles. Structural diversity and spatial heterogeneity play an important role in all of these functions and require increased attention. Spatial pattern or heterogeneity is important to ecosystem function at all spatial scales from centimeters to kilometers, not just the larger scales. The relevance of spatial patterns to ecosystem function, including the statistical patterns and significance of the relationships, depend on the function or parameters chosen and the spatial and temporal scales of interest. As a consequence, few, if any, general principles exist for interpreting the effects of landscape heterogeneity on ecosystem function. For example, heterogeneity does tend to increase the number of niches available and, hence, the diversity of environmental conditions that are present.Whether the effects of this increased diversity are positive or negative depends on the processes or organisms of interest. One important conceptual challenge in studying landscape heterogeneity is to move beyond the classic patch-corridor-matrix model to approaches that incorporate networks and gradients.