关键词: 碳源, 溶磷能力, 氮源, 白网链霉菌, 遗传稳定性

Abstract: The Tarim Basin is one of the regions with the most serious land desertification in China. In this study, the spatial and temporal variations of land desertification in the Tarim Basin during 2000-2014 were monitored and analyzed using RS and GIS technologies based on the vegetation coverage from Normalized Difference Vegetation Index (NDVI) data of MODIS. Besides, the impacts of climate change and human activities on the desertification for the Tarim Basin were investigated. The results showed that: (1) The Tarim Basin was characterized by the largest proportion of severe desertification (64.63%), followed by moderate desertification (17.70%), and slight desertification (9.95%), and nondesertification was the least (4.18%). The gravity center of the severe desertification migrated to the northeast part in the past 15 years, with a migration distance of 21.08 km. (2) During the past 15 years, the severe desertification area decreased at a rate of 0.0076 km²·a^-1. However, the moderate desertification area increased rapidly, with an average annual rate of 0.0169 km²·a^-1, the slight desertification area had a slightly increasing trend with a rate of 0.0093 km²·a^-1, and the proportion of nondesertification increased significantly with a rate of 0.0289 km²·a^-1. (3) The changes of desertification were the results of the interaction of climate change and landuse change. Annual precipitation was closely related to annual average vegetation coverage with a correlation coefficient of 0.45. At the same time, the expansion of cultivated land area, which had increased by 13.18×10³ km² during the last 15 years, accelerated the desertification processes of the peripheral oasis area.

Key words: genetic stability, phosphate solubilization capacity, nitrogen source, carbon source, Streptomyces albireticuli