土地利用/覆被变化对地质灾害发育的影响研究

2018年8月印度喀拉拉邦遭受强降雨，引发大量地质灾害，造成巨大的经济损失和人员伤亡。为研究农业化进程中土地利用/覆被变化对地质灾害发育的影响，探求适宜的人地协调发展模式，以该地区受灾最严重的伊都基为研究区，基于已有的灾害点数据，利用Google Earth高分辨率遥感图像目视解译获取研究区灾害发生前8 a(2010年)和灾害发生时（2018年）的土地利用数据，基于Landsat TM/OLI数据提取的归一化植被指数计算研究区植被覆盖度，对比分析该地区地质灾害的发育与土地利用/覆被变化之间的关系。研究结果表明：(1)伊都基地区灾害点主要集中在中北部地区，分布在种植林、种植灌丛、建筑物、道路等人类活动影响较大的区域，该区域灾害点占总灾害数的80.46%；(2)伊都基地区灾害点的土地利用变化虽然较小，总体变化率为37%，但土地利用变化主要发生在种植灌丛、种植林等与人类活动密切相关的土地利用类型中；(3)伊都基地区植被覆盖度下降率为16.70%，在空间分布上，灾害点易发区域与植被覆盖度下降区域有较强的关联性。

Research on the Impact of Land Use/Cover Change on Geological Disaster Development

An extreme rainfall event hit Kerala in India， in August 2018， triggering a large number of geological disasters， causing serious economic losses and casualties. In order to study the impact of land use and its changes during the process of agriculturalization on the development of geological disasters， and to explore a suitable man-land coordinated development model， based on the disaster point data of Idukki， which is the most severely affected area， this paper obtained the land use data of each disaster point in 2010 and 2018 from Google Earth high-resolution remote sensing images and Landsat TM/OLI data extraction normalized difference vegetation index calculation of vegetation coverage to analyze the relationship between geological disasters and land use and its changes. The results show that： ①disasters in the study area are mainly concentrated in the north-central region， where planting forests， planting shrubs， buildings， roads， and other lands with human activities influence accounted for 80.46% of the total disasters； ②although land use change at the disaster site in the study area is few with the overall rate of 37%， however the changed land use are closely related to human activities， such as planted shrubs， planted forest land； ③the vegetation coverage decline rate in the study area was 16.70% ， while disaster susceptibility areas had a better response to areas with reduced vegetation coverage spatially.