湖南境内沅水流域地质灾害形成因素分析

沅水流域流经湖南省的西部地区，由于地质环境和社会经济背景的特殊性，已成为湖南省地质灾害的主要分布区。通过对流域内地质灾害发育特征的归纳，着重从自然影响因素和人类活动两个方面来分析流域内地质灾害的形成。主要采用灰色关联理论来分析流域内大气降水、地形条件和人类活动等3个主要致灾因子的关联度，其结果分别为0．8332、0．6589和0．5654，从而来探求流域内地质灾害灾变机理的规律性，为流域内各个地区的防灾减灾提供依据，最大限度减少地质灾害所造成的经济损失，促进流域内社会、经济、生态环境的可持续发展。

FORMATIONAL FACTORS ANALYSIS ON GEOLOGICAL HAZARD OCCURRING THROUGHOUT THE YUANSHUI WATERSHED IN HUNAN

The Yuanshui watershed flows throughout the western region of Hunan Province. It appears to be a main area for the development of geological hazards in the province due to the specialties of the regional geological conditions and socio-economic development background. This study approaches the development processes of geological hazards from viewpoints of physical actions and anthropogenic activities, based on understanding the growth characters of geological hazard. The major hazard-caused factors including atmospheric rain fall, topographical features and anthropogenic activities, are considered for understanding the relation to the development of hazards using Gray correlation theories. The study shows that the above three correlation factors are 0.8332, 0.6589 and 0.5654 respectively. Therefore, the regularities regarding the formation and development processes of geological hazards occurring in the area are summarized. The present study results set a basement for us to make strategy decision on hazard protection and reduction, as well as minimizing economic losses so as to keep a sustainable development for the area.