Using an index of habitat patch proximity for landscape design

Abstract

A proximity index (PX) inspired by island biogeography theory is described which quantifies the spatial context of a habitat patch in relation to its neighbors. The index distinguishes sparse distributions of small habitat patches from clusters of large patches. An evaluation of the relationship between PX and variation in the spatial characteristics of clusters of patches showed that reduction in the isolation of patches within a cluster produced exponential increases in PX, and that increase in the size of those patches produced a more modest linear increase in PX. Simulations using neutral model landscapes were used to determine the effect of the scale of analysis on PX. Increased size of the neighborhood considered around a habitat patch (proximity buffer) produced linear increases in PX, the slope being dependent on the proportion of the habitat of interest on the landscape. The proximity index was used to evaluate three alternative conservation reserve designs in an agricultural landscape, and comparisons were made among designs consisting of the same area of forest habitat added to the landscape. The `single, large` reserve design produced the greatest increase in mean PX values among forest patches on the landscape when the total area of forest added was >= 842 ha, and the `several, small` reserve design produced the greatest increase when the total area of forest added was

Citation

Gustafson, Eric J.; Parker, George R. 1994. Using an index of habitat patch proximity for landscape design. Landscape and Urban Planning 29 (1994) 117-130