四川盆地紫色土丘陵区水土流失及防治对策

四川盆地丘陵区是该省水土流失最严重的地区。也是该地区生态环境恶化、自然灾害频繁、农村经济落后、人民生活贫穷的重要原因。文章根据四川盆地丘陵区水土流失面积大、强度高的特征及其致害因素，探讨了水土流失原因。水土流失破坏生态环境及耕地资源，淤积江河湖库，加剧水旱洪涝灾害，造成土壤肥力下降，土壤蓄水抗旱能力降低。由此提出了一些相应的防治措施——加强生态环境建设，整治坡面水系，搞好农田基本建设，强化人口／管理等，从而使水土流失得到控制，生态环境得到改善。加强对紫色砂页岩丘陵区的治理，合理开发利用土地，提高土地利用率和生产率，不仅利于四川盆地丘陵区的经济发展，而且对改善长江上游乃至整个长江流域的生态环境也具有重大的现实意义。

Soil erosion and the controlling countermeasures for the purple soil hilly areas in the Sichuan Basin

Soil erosion of hilly areas in the Sichuan Basin is more serious than any other regions in Sichuan Province, and it is an important reason that ecological environment is deteriorating, natural disaster is frequent, rural economy is laggard and people living conditions are hard. Based on the serious features and induced factors of soil erosion in hilly areas of Sichuan Basin, this paper probed into the causes and harm of soil erosion including destroying ecological environment and farmland resource, sedimentation of rivers and lakes, deterioration of flood and drought disasters, reduction of the soil fertility and the capacities of the water storage and drought resistance. Therefore some controlling countermeasures are put forward in order to further control soil erosion and improve the ecological environment, such as ecological environment construction, overland flow improvement, farmland construction and population management. So the land can be reasonably exploited and utilized and utilization ratio and productivity in the purple sand shale hilly areas can be improved. These are not only neccessary for the economic development in hilly areas in Sichuan Basin, but also has grand practical significance and profound influence to improve ecological balance of the Yangtze River watershed.