Landform Effects on Ecosystem Patterns and Processes

Abstract

U nderstanding the form, behavior, and historical context of landscapes is crucial to understanding ecosystems on several temporal and spatial scales. Landforms, such as floodplains and alluvial fans, and geomorphic processes, such as stream erosion and deposition, are important parts of the setting in which ecosystems develop and material and energy flows take place. Over the long term, geomorphic processes create landforms; over a shorter term, landforms are boundary conditions controlling the spatial arrangement and rates of geomorphic processes. Ecosystems respond to both landforms and geomorphic processes. The history of geomorphic processes may be expressed directly in the composition and structure of vegetation, where geomorphic events and vegetation develop together. Geomorphic processes operating before the establishment of existing vegetation, or those subtly coexisting with the vegetation, may have their greatest influence on vegetation through controlling patterns of soil properties across a landscape, as in toposequences