Landscape fragmentation assessment using a single measure

Measurement of fragmentation is crucial for determining its consequences an d to develop policy for nature conservation. We propose a fragmentation mea sure /phi/ which combines, using a multidimensional Euclidean distance, 4 m ain characteristics of fragmented landscapes: total habitat area, total hab itat perimeter, number of patches, and patch isolation. Its properties can be summarized as: 1) /phi/ reflects the overall fragmentation status; 2) ev ery component of /phi/ is accepted as a measure of fragmentation; 3) every component of /phi/ is a normalized variable; 4) every component of /phi/ is easy to compute; 5) average patch size, interior habitat, and habitat conn ectedness are included indirectly in /phi/; 6) /phi/ is independent of the land-use type; and 7) /phi/ can be calculated for raster and vector data. W e show that the normalized values composing /phi/ prevent misinterpretation of features as fragment number or boundary length. A sensitivity analysis, based upon artificial patterns, showed that increasing fragmentation is co rrelated with smaller values of /phi/. Wildlife managers are encouraged to use /phi/ for objective evaluation of fragmented landscapes.