Abstract:

Water productivity refers to the quantity or value of products produced by per unit volume or value of water resources. Improving water productivity is an important direction for the sustainable development of desert oasis. The Hexi Corridor is not only an important ecological barrier of northwestern China， but also a typical irrigated agricultural area in the northwestern China. After more than 70 years of development， the Hexi Corridor has made very significant achievements in oasis irrigation agriculture， national economic development and ecological protection construction. However， low agricultural water productivity still affects the development of oasis profoundly. This paper combs the current status of utilization of water and soil resources in the Hexi Corridor， analyzes the characteristics of oasis soil organic matter and water holding capacity as well as their relationships with water productivity， and proposes the approaches to improve oasis water productivity by increasing soil organic matter and soil water holding capacity. In order to protect the safety and stability of the Hexi Corridor ecological barrier and the sustainable development of oasis agriculture， it is recommended that respecting the process of oasisization in oasis management， protecting irrigated desert soil resources， and restricting the conversion of irrigated desert soil cultivated land with good productivity into non-cultivated land strictly； determining the areas that should be prioritized for improvement according to the soil condition， especially the soil with surface organic matter of 1.0%-1.8% and field capacity between 20% and 25%； in order to realize the improvement of agricultural water productivity in the oasis of the Hexi Corridor.

Key words: Hexi Corridor, oasis, water productivity, soil organic matter, field capacity