Spatial and auto correlation of ecological change: disturbance and perturbation analysis in Circeo National Park ( south Latium, Italy)

摘要

"Ecological change" has different meanings: disturbance and perturbation. In this study, disturbance and perturbation were both spatially characterized using Normalize Vegetation Index (NDVI) delta maps (25 years: 1984- 2009) derived by Landsat 5TM imagery. In Circeo National Park, the ecological change spatial pattern was characterized using geostatitsc techniques. Instead, the spatial correlation of data was performed elaborating Euclidean Distance (ED) maps of urban and industrial areas and combining ED maps with disturbance cartography. At 45° a strong anisotropy was revealed by the empirical semivariogram of NDVI losses density, whereas NDVI's gains showed isotropy. The perturbation corresponds to processes of forests re-colonization, whereas the disturbance was human-induced.