Journal of Geographical Sciences ›› 2008, Vol. 18 ›› Issue (4): 483-498.doi: 10.1007/s11442-008-0483-9

• Climate and Environmental Change • Previous Articles     Next Articles

Soil properties related to land-use systems in oases of Sangong river watershed, Xinjiang

LUO Geping, CHEN Xi, XU Wenqiang   

  1. Key Laboratory of Oasis Ecology and Desert Environment, Xinjiang Institute of Ecology and Geography, CAS, Urumqi 830011, China
  • Received:2008-01-17 Revised:2008-05-26 Online:2008-12-25 Published:2008-12-25
  • Supported by:

    National Natural Science Foundation of China, No.40671015, No.40711120200; Project of “Western Light of CAS” Related to Eastern Scholar, No.20051048

Abstract:

Understanding the effect of human activities on the soil environment is fundamental to understanding global change and sustainable development. In the process of transformation of tropical rain forests and semiarid grasslands to farmlands, land degradation usually occurs. But the transformation of arid desert landscape to oasis is found to have quite different consequences. Taking an alluvial plain oasis in the north piedmont of the Tianshan Mountains as a case study, we investigate oasis soil properties related to different land-use systems during the transformation of arid desert to oases. Selected land-use systems consisted of an annual crop field less than 3 years old, annual crop field 3?6 years old, annual crop field more than 6 years old, perennial crop field less than 4 years old, perennial crop field of 4-6 years old, perennial crop field more than 6 years old, abandoned farmland more than 3 years old, woodland field more than 6 years old, ecological forestation field, natural shrubbery field, desert grass land, and saline or alkaline field. Different land-use systems affect significantly the distribution of sand, silt and clay. Sand content in oasis soil tends to decrease with cultivation years but silt and clay contents tend to be increased in the oasis soils. Soil fertility is higher in the land-use systems under strong human disturbance than under weak human disturbance. Oasis soil nutrients also tend to increase with cultivation years. Soils have a significantly lower salinity in the land-use systems under strong human disturbance than under weak human disturbance. Soil organic matter and nutrients of the annual and perennial crop systems in the oasis tend to increase with cultivation time with the oasis soil acting as a carbon sink. These results show that soils are not degraded and the soil quality is gradually improved under rational land use and scientific management patterns, including uniform exploitation of land resources, effective irrigation systems, sound drainage systems, balanced fertilizer application, crushed straw return to soil and transformation of annual crop fields to perennial ones.

Key words: annual crop, perennial crop, carbon sink, land-use system, oasis, soil property