JOURNAL OF NATURAL RESOURCES ›› 2019, Vol. 34 ›› Issue (4): 853-866.doi: 10.31497/zrzyxb.20190414

• Resource Evaluation • Previous Articles     Next Articles

Technical efficiency of crop irrigation and its determinants in the arid areas of Northwest China

LI Gui-fang1(), ZHOU Ding-yang2, SHI Min-jun3()   

  1. 1. School of Economics, Renmin University of China, Beijing 100872, China
    2. School of Natural Resources, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
    3. School of Public Affairs, Zhejiang University, Hangzhou 310058, China
  • Received:2018-08-09 Revised:2019-01-27 Online:2019-04-20 Published:2019-04-20

Abstract:

The shortage of water resources has become a hard constraint to the sustainable development of the arid areas of Northwest China. Increasing the technical efficiency of crop irrigation (TECI) and reducing agricultural irrigation water use may be one of the possible ways to ease the contradiction between water supply and demand. Based on the survey data of farmers in Zhangye city in 2014, this paper uses the DEA-Tobit model to analyze the TECI and its determinants in different types of irrigation zones in the middle reaches of the Heihe River Basin. The results show that there is a certain improvement space of TECI of main crops in the typical irrigation zones. With the other inputs unchanged, if the TECI reaches the current highest level in different types of irrigation zones, in order to produce the same amount of the seed maize and maize, the irrigation water can be reduced by 34.47% and 38.15% in the plain irrigation zone; in order to produce the same amount of the cotton, seed watermelon and maize-wheat (inter-corn), the irrigation water can be reduced by 48.42%, 34.82% and 22.99% in the northern desert irrigation zone; in order to produce the same amount of the wheat, potato, barley and maize, the irrigation water can be reduced by 14.48%, 30.75%, 25.50% and 35.96% in the mountain irrigation zone. In addition, the coefficient of variation of the TECI in different irrigation zones is negatively related to the proportion of cropland area, and there is a significant difference in the production management level of farmers who grow the same crop in the same irrigation zone. What's more, the fragmentation degree of cultivated land and the expansion of cultivated area have negative effects on the TECI in different irrigation zones, improving the quality of cultivated land has a significant positive effect on main crops in the northern desert irrigation zone. Increasing well water irrigation has a positive effect on crops such as maize in plain irrigation zone and wheat, potato, maize in mountain irrigation zone, and there is an inverted U-shaped relationship between irrigation frequency and the TECI. However, the influence of farmers' demand for cultivation and the attitude towards risk need to be judged based on specific conditions. Therefore, determining the production scale, accelerating the optimization and reorganization of cultivated land and improving the quality of cultivated land, rationally guiding the use of well irrigation, and enhancing the water conservancy facility and the flexibility of river water irrigation are the main ways to improve the TECI in the Heihe River Basin.

Key words: Zhangye city, Heihe River Basin, irrigation zone, technical efficiency of crop irrigation, DEA-Tobit model