Studies On Soil Ecological Degradation And Its Ecological Adaptability Of Bioremediation

Soil ecosystem is an organic integrative system consisting of biotic system, soil system and environment system mutually and harmoniously through material circulation, energy conversion and information transmisson. Soil ecological degradation can be defined as the process and phenomenon of a series of deterioration of soil ecological environment such as structural destruction and functional recession of soil ecosystem, decrease of soil biodiversity and productivity, dcsertification, drought, hardness, acidification and salination of soils, deficit and unbalance of soil nutrients, and loss of soil and water, resulting from human activities and adverse natural environmental conditions. It is related to the definition of soil degradation in soil science and the definition of ecological degradation in ecology, is the focal points of soil science and ecology in the twenty-first centuly. Therefore, restoration and reconstruction of degraded soil ecosystems is not only a hot points of soil science and ecology but also a difficult points that is concerned by the whole mankind and need solving urgently. However, soil scientists usually attached importance to the degradation of soil system itself, neglecting studying the degradation of biotic system. On the contrary, ecologists paid attention to studying the degradation of vegetation system, usually neglecting studying the degradation of soil system and soil biotic system, and was wanting in studying the relationship among vegetation system, soil biotic and soil system. Among the assessment indices of soil ecological degradation and restoration and reconstruction of degraded soil ecosystems, or the assessment indice of biotic activity degradation was paid attention to, it was lack of comprehensive A part of cooperation projectStudy on Land Degradation and its Control in the Typical Region of Dry and Hot Valley of the Jinsha Rivc( by Yunnan Province and the Chinese Academy of Sciences. assessment index system and relationship between above and below ground biodiversity. To be mentioned, it was lack of studying on ecological adaptation of specific species to degraded soil ecological conditions and extremely environmental factors by morpha, physiological ecology and nutrient ecology; it was lack of studying on bioremediation of specific species to degraded soils. Dry and hot valley of the Jinsha River is an extreme type in the dry valley of Hengduan mountain area, and Yuanmou dry and hot valley is the typical region of the dry and hot valley region of the Jinsha River. There is advantageous to the growth and development of tropical and subtropical plants because of abundant light and heat in the region. The region is a typical ecotone due to prominent contradictions of water and heat, and light and soil fertility, low vegetation coverage, and serious loss of water and soil. Vegetation restoration and reconstruction is very difficult because of serious desertification, drought, deficit and unbanlance of soil nutrients, and lower productivity of zonal soils (dry-red soils) and vertisols in this region. Therefore, this project dealt with the vegetation features, soil physic, chemical and biological characteristics, and plant community biomass and biodiversity of two types of different degradation degree of soil ecosystems in the dry and hot valley, discussed the relationships among soil system, soil biotic system and vegetation system, elaborated the process and mechanism of soil ecological degradation from the angle and level of soil ecosystem, biotic community and population by the methods of combining field investigat...