基于GIS与AHP耦合技术的土地沙漠化模型研究

晋陕蒙 (西 )地区的土地沙漠化受控于多种因子 ,在详尽分析了土地沙漠化的各种因子基础上 ,确定了母质类型、植被覆盖、地貌类型、沟壑密度、土地利用类型、矿山开发面积、大风强度七个致灾因子 ,并分别建立了它们各自的子专题层图。利用先进的层次分析法 (AHP)确定了影响沙漠化的各致灾因子的权重系数 ,通过地理信息系统 (GIS)与AHP的耦合技术 ,对各子专题层图进行了加权复合叠加 ,利用频率和频数分布直方图 ,确定出土地沙漠化的分区阈值 ,构建了土地沙漠化危险度评价的多源地学信息复合叠加模型 ,并对土地沙漠化危险度进行了分区评价 ,共划分为五个区 ,即强度区、中度区、轻度区、潜在区、未沙区。土地沙漠化评价模型的建立 ,为土地沙漠化的分区评价与预测提供了理论依据 ,使评价结果更科学、合理、准确。

Study on Desertification Assessment Model based on GIS and AHP

The desertification is determined by multi geological elements in the area around Shanxi province and Inner Mongolia Autonomous Regions. Based on the geological elements analyses, seven dominating factors are selected, i.e.soil, vegetation, landform, ravine, land use, mine digging and wind intensity, and the thematic layers of each one are constructed. Each layer's weight is determined through AHP(Analytical Hierarchy Process) technique, and the layers are superimposed according to the respective weights. The coupling model based on GIS and AHP is established for desertification assessment, and the study area divided into five grades, i.e. strong, middle, weak, latent and none grade. This construction of coupling model has laid a theoretical base for desertification studying and made it more quantificational, standard and comprehensive.