| Guizhou province is located in the center of a widespread karst region in southwest of China which is the largest one in the world. The province is undergoing the process of rocky karst desertification, which apparently deteriorated in recent years. Furthermore, it becomes an obstacle to the development of local economy and improvement of local citizen s living standards. It is well known that detailed study on the mechanism of rocky desertification lays the bases to harness it, however, the present researches are mainly focused on qualitative analysis and is obviously lacking in quantitative ones. Currently, there is no a uniform standard to classify the karst rocky desertification. Moreover, the mechanism of soil degradation is still uncertain in process of rocky desertification, which brings a great obstacle to the control of rocky karst desertification process.This paper made quantitative analysis of the roles of soil and vegetation degradation in the process of rocky desertification, in order to confirm the nutrient elements' co-variances within soil- vegetation system and to analysis the variances of soil and vegetation and the co-variance between them in the process. Catchments named Cha'erpu in Huajiang gorge in Guizhou province was been taken as an example. The analysis also aimed to confirm that whether the method to classify rock karst desertification from a point view of landscape could embody the essence of the desertification. The following conclusions were drawn from the analysis.(1) The soil in the studied area was featured as following: Its pH values ranged from 6.9 to 7.8; values of total and changeable calcium being high; rich in nitrogen; organic matters, available contents and total nutrients also being high except that for potassium.(2) The ashes of plants in rocky karst desertification regions were rich in calcium and nitrogen, lacking of iron, zinc, potassium and phosphorus. Meanwhile,...
|
PDF Full Text Request