
Water Saving Irrigation for Rice and Its Effect on Environment
Mao Zhi
Strategic Study of CAE ›› 2002, Vol. 4 ›› Issue (7) : 8-16.
Water Saving Irrigation for Rice and Its Effect on Environment
Mao Zhi
Rice is one of the most important food crops contributing about 40% of the total food grain production in China. Out of about 110 million hectares of area sown food crops, 28% is covered by rice. Since 1980s, the shortage of water resources has become an important problem for agricultural production in rice planing areas and many water saving regimes for rice have been tested, advanced, applied and spread in different regions of China. In this paper, based on the results of experiment and the experience of spread of these new irrigation regimes, the following four main kinds of water saving irrigation regimes in China have been classified viz. (1) combining shallow water depth with “wetting” and “dry” (SWD), (2) alternate wetting and drying (AWD) ,(3) semi-dry cultivation (SDC) and (4) rainwater storage (RS). The standards of field water control and potential of saving water, increasing rice yield and water productivity of these regimes are introduced and explained. The selection and attention points of application for the four regimes are presented and the causes of sustainable saving water and increase in water productivity and the environmental impacts by adopting these regimes are analyzed and discussed.
rice / water saving irrigation / irrigation regime / potential of water-saving / enviromental impact
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