Karst Peak Clump Depression Ecological Environment Characteristic And Herb Productivity

In the karst peak-cluster depression area of the northwest of the Guangxi Zhuang clan Autonomous Region, because of the agricultural mode of production of "slash-and-burning cultivate" for a long time makes this area soil erosion serious and soil nutrient melts barrenly. The land was unreasonable in utilization of resources now and the agricultural production structure was too single, which had already become the restriction factor of agricultural sustainable development of this area. The herbage prevents soil erosion improve soil fertility and promote such function as the structural adjustment of agricultural production, etc.. Introduce herbage into the agricultural production of the karst peak-cluster depression areas, regard herbage as the tie. Through growing grass raise the domestic animal and combine agriculture, husbandry, forestry with. Given the combination of ecological benefits, economic benefits and social benefits as well as promote local agriculture sustainable development.To solve those problems this thesis has studied ecological environment factor characteristic and under this special environmental condition on the basis of combining forefathers studies. Moreover it has analyzed interrelation between each ecological factor and four herbages. The main conclusion was as follows:There were very great differences between the depression and hillside field in the peak clump depression system of the karst. The sunshine time of the hillside field and content of soil moisture in the ecological environment factors were obvious less than that of the depression, Total sunshine time depression have 1025.4 h the whole year, hillside field only 710.1 h, which 69.25% of the depression only. The hillside field soil layer was bad to reserve water and the impact of precipitation on hillside field was smaller than on the depression. The soil 15～20 cm water content in the depression is 34.8% in the abundant rainfall June, while the hillside field are 24.9%. There was a structure of inversion with warm top and cold bottom in the clump depression system, air temperature is lower by 3 degrees Centigrade than the hillside field in high-temperature season in the depression, soil 20 cm is lower by 4 degrees Centigrade than the hillside field. Obviously, the difference was remarkable.