Soil Properties And Vegetative Rehabilitation Techniques In A Typical Dry-hot Valley Of The Jinsha River Basin

Taking the Yuamnou Dry-hot Valley, typical of the Jinsha River Dry-hot Valleys as a case, the relationships of plant growth to soil conditions were analysed based on the assessment of soil properties and soil quality in this region. The soils in the region were characterized by thin layer, weak structure, gravel/fragmental composition, compacted surface and drought, etc. Soil water properties are important factors affecting vegetative rehabilitation in spite of low soil organic content and lack in soil nutrients. Decline in soil infiltration rates causes the deterioration of soil water properties, resulting in soil drought. Human intervention such as overgrazing resulted in a great decline in soil infiltration rates, which are an important reason for soil degradation and soil drought The experimental results showed that plant biomass and productivity increased significantly with the increase of soil infiltration rates. Despite the same tpyes of soils in this region (the majority is dry red soil), different types of soil parent materials/rocks imposed an important influence on soil infiltration due to soil degradation such as the removal of soil material and appearance of gravels/rock fragments. As a result, plant growth is closely related to the types of rocks.As far as vegetative restorage techniques is concerned, an integrated natural-socioeconomic measure which is not passively adapt to local socioeconomic conditions, but an active method was proposed based on a comprehensive consideration for soil conditions and socioeconomic ones.