Cultivation Effects on Soil Fertility Dynamics of the oasis croplands in the Southern rim of the Tarim Basin

Cultivation Effects on Soil Fertility Dynamics of the oasis croplands in the Southern rim of the Tarim Basin

Twenty croplands in the Cele oasis, at the southern margin of the Tarim Basin of Xinjiang, were selected, representing 100, 80, 30, 15 and 10 years of cultivation, to investigate the soil fertility over time. After longterm cultivation, significant increases were observed in soil organic matter (SOM) and total macronutrients. The key factors contributing towards the soil fertility index (SFI) were SOM, available potassium (AK) and phosphorus. The values of SFI declined in the following order: 80 (0.95)>100 (0.68)>30 (0.43)>15 (0.41)>0 (0.37)>10 (0.34) years. This suggests that the long-term cultivation practices have demonstrated obvious positive effect on the soil fertility. However, there was a risk of land degradation and deterioration of soil fertility once the cultivated croplands were abandoned in the initial 10 years. .