The arid areas in China are mainly located in North China and NorthwestChina. The North China is the main region for food production. There is 31. 19% of the totalfarmland and 26. 01% of the total population, but only...The arid areas in China are mainly located in North China and NorthwestChina. The North China is the main region for food production. There is 31. 19% of the totalfarmland and 26. 01% of the total population, but only 6. 14% of the available water resources ofChina. Groundwater is over pumped (6. 53 X 10~9m^3 every year) in the regions of Beijing, Tianjin,and Hebei Province, so water supply could not meet the water demand there. The distribution of waterin Northwest China is uneven, some inland rivers and lakes are dried up, and desertification hasexpanded since river water in the upper and middle reaches is diverted for irrigation. Up to 2050,population will be up to 1. 6 X 10~9 in China, and industry will be developed fast, therefore 50% ofthe water supply will be used by industry and resident, and water for agriculture will be decreasedyear by year. In the coming 50 years, water demand for agriculture will be increased by 5. 6 x10^9m^3 in the Huanghe (Yellow) River valley, and by 1. 7 x 10~9m^3 in the Northwest China. It willbe impossible for the Huanghe River to meet the water demand, because it always dried up in the coldhalf year since 1984. To avoid water shortage of agriculture in the arid regions, it is necessaryto divert water from the Changjiang (Yangtze) River in the south of China, and to use waterefficiently. It is the best way to use drip irrigation in agriculture, recycle water in industry andresident use, and control water pollution. Otherwise water shortage in the arid regions willrestrict the development of agriculture in China.展开更多
文摘The arid areas in China are mainly located in North China and NorthwestChina. The North China is the main region for food production. There is 31. 19% of the totalfarmland and 26. 01% of the total population, but only 6. 14% of the available water resources ofChina. Groundwater is over pumped (6. 53 X 10~9m^3 every year) in the regions of Beijing, Tianjin,and Hebei Province, so water supply could not meet the water demand there. The distribution of waterin Northwest China is uneven, some inland rivers and lakes are dried up, and desertification hasexpanded since river water in the upper and middle reaches is diverted for irrigation. Up to 2050,population will be up to 1. 6 X 10~9 in China, and industry will be developed fast, therefore 50% ofthe water supply will be used by industry and resident, and water for agriculture will be decreasedyear by year. In the coming 50 years, water demand for agriculture will be increased by 5. 6 x10^9m^3 in the Huanghe (Yellow) River valley, and by 1. 7 x 10~9m^3 in the Northwest China. It willbe impossible for the Huanghe River to meet the water demand, because it always dried up in the coldhalf year since 1984. To avoid water shortage of agriculture in the arid regions, it is necessaryto divert water from the Changjiang (Yangtze) River in the south of China, and to use waterefficiently. It is the best way to use drip irrigation in agriculture, recycle water in industry andresident use, and control water pollution. Otherwise water shortage in the arid regions willrestrict the development of agriculture in China.