关键词: 证据权, GIS, 岩溶塌陷, 区划, 预测

Abstract: Weights of evidence (wofe) modeling and its application based on GIS are introduced. Wofe is applied to the zonation of karst collapse. Sensitivity of karst collapse around West Lake of Hangzhou is analysed. The cell size used in the analysis is 10 m×10 m. Spatial data of strata, structure and overburden is extracted from the study area. Spatial association between evidences and karst collapse is analysed, and contrasts are calculated. The studentized contrasts, which serve as a guide to statistical significance of spatial association, give cut off values to convert multiclass evidential data into binary pattern. Five evidences appropriate to the model are finally selected and converted into binary patterns, such as the strata unit, strata boundary of Gufeng formation - Qixia formation and of Huanglong formation - Laohudong formation, proximity to EW-NW trending structure features, proximity to NE trending structure features. Posterior probability of each cell which reflects degrees of karst potential collapse is calculated. The ratio of numbers of known collapses to the numbers of predicted collapses is 0.864, which indicates conditional independence among evidences with respect to karst collapse. The special application of wofe shows that the model is adapted to zonation of karst collapse.

Key words: weights of evidence, GIS, karst collapse, zonation, prediction