盐池县地质灾害遥感调查及空间分布特征分析

宁夏盐池县地处黄土高原区，地质灾害较为频繁。以SPOT6、RapidEye、无人机以及LandSat8 OLI等多源遥感数据为基础，通过研究遥感影像特征，建立地质灾害解译标志，共解译出滑坡125处、崩塌84处、泥石流19处、地面塌陷区3处。结合区域地理地质环境特征，总结了研究区地质灾害点的基本特征，并利用GIS技术对灾害点进行点密度分析，在此基础上划分了7个集中分布区，归纳了盐池县地质灾害点的空间分布特征及规律；同时，对研究区地层构造、植被、地形等因素与地质灾害点空间分布特征的相关性进行了讨论。研究结果表明:盐池县地质灾害点具有规模小，灾害轻；点密度整体南高北低，且南部聚集、北部分散;地层、植被、坡度、坡向等因素与地质灾害有着密切的联系。

Survey of geological hazards by RS and the spatial distribution characteristics in Yanchi county

Yanchi county in the Ningxia Autonomous Region lies in the Loess Plateau, where ecological environment is weak and severe geological hazards frequently occur. Based on the RS data such as SPOT6, RapidEye, LandSat8 OLI and UAV, 125 landslides, 84 collapses, 19 debris-flows and 3 surface collapses are interpreted by examining the RS image characteristics and by building interpretation indication of geological hazards. According to regional geographical and geological environmental characteristics, the basic features of the geological hazard points are summarized. Seven concentrated distribution regions are divided and the spatial distribution characteristics of geological hazard points are characterized on the basis of the point density analysis by employing the GIS technology. This paper uses the spatial analysis function of GIS to discuss the relationship between the geological hazard spatial distribution and vegetation and topography. The results show that geological hazard points in the study area are characterized by small size, low hazard and such threat objects as village, farmland and country roads. Point density is high in the south and low in the north, suggesting that the hazard points are concentrated in the south and dispersed in the north, and the concentrated region is located in Mahuangshan-Xuejiapan. The strata, vegetation, slope and aspect are related to geological hazards.