Correlation of alpine vegetation degradation and soil nutrient status of permafrost in the source regions of the Yangtze River, China

The impacts of alpine vegetation degradation on the main soil nutrients in the permafrost were studied by the comparative analysis of typical plots in the source regions of the Yangtze River. It is found that vegetation degradation has a severe effect on the content of the main soil nutrients, especially in the topsoil (0–10 cm) where the soil nutrients content were changed. There are good correlations between soil organic matter (SOM) and total nitrogen (TN), total phosphorus (TP) and total potassium (TK) in alpine soil. The change to soil nutrients increases concomitantly with the increasing intensity of vegetation degradation. Soil nutrients change dramatically in the thermokarst lakes in the surrounding area where vegetation is severely degraded. The ratio of SOM, TN, TP and TK in different soil layers of the adjacent thermokarst lakes is 5.88, 5.14, 3.86 and 4.43, respectively. The vegetation degradation accelerates the degradation of alpine soil environment in alpine frozen soil.