Northwest China includes Xinjiang Ugyur Autonomous Region, Qinghai Province, Gansu Province, Ningxia Hui Autonomous Region and Shaanxi Province, covering 308×10^4km^2. It is located in the warm-temperate zone and...Northwest China includes Xinjiang Ugyur Autonomous Region, Qinghai Province, Gansu Province, Ningxia Hui Autonomous Region and Shaanxi Province, covering 308×10^4km^2. It is located in the warm-temperate zone and the climate is arid or semi-arid. Precipitation is very scarce but evaporation is extremely high. The climate is dry, the water resources are deficient, the ecoenvironment is fragile, and the distribution of water resources is uneven. In this region, precipitation is the only input, and evaporation is the only output in the inland rivers, and precipitation, surface water and groundwater change with each other for many times, which benefits the storage and utilization of water resources. The average precipitation in this region is 232 mm, the total precipitation amount is 7003×108m^3/a, the surface water resources are 1891×10^8m^3/a, the total natural groundwater resources are 1150×10^8m^3/a, the total available water resources are 438×10^8 m^3/a, and the total water resources are 1996×10^8m^3/a and per capita water resources are 2278 m^3/a. The water resources of the whole area are 5.94×10^4m^3/(a.km^2), being only one-fifth of the mean value in China. Now, the available water resources are 876×10^8m^3/a, among which groundwater is proximate 130×10^8m^3/a.展开更多
Based on affirming the tremendous benefits that water resources of rivers can provide in their exploitation, main environmental problems and their countermeasures have been proposed and analyzed in this paper. It is a...Based on affirming the tremendous benefits that water resources of rivers can provide in their exploitation, main environmental problems and their countermeasures have been proposed and analyzed in this paper. It is argued that multiple measures should be applied to solving those problems by simultaneously carrying out engineering measures, scientific research and also programs to cultivate the society’s awareness, aimed at a sustainable development strategy for exploiting water resources.展开更多
In shallow groundwater agricultural fields, water exchanges between groundwater and soil water happen frequently and intensively. This paper analyzes the regale of subsurface water during the growing period of winter...In shallow groundwater agricultural fields, water exchanges between groundwater and soil water happen frequently and intensively. This paper analyzes the regale of subsurface water during the growing period of winter wheat from October 1998 to June 1999 in Yucheng area. During an 8- month period of winter wheat growth. 456.66 mm of evapotranspiration and 75.61mm of groundwater evaporation were measured with a new model lysimeter. Groundwater at 1.60-2.40 m depth of water tables contributed 16.6% of total water used by winter wheat under natural. precipitation and irrigation treatment.The results showed that a significant proportion of field evapotranspiration was supplied by groundwater evaporation, whereas the role of groundwater evaporation was not considered during irrigation, leading to soil water percolation into groundwater.In order to improve water use efficiency of crops, some measures were put forward in the paper. Effective use of groundwater and soil water is a key countermeasure for sustainable development of water-saving agriculture and Water resource exploitation in Yucheng area展开更多
基金National Natural Science Foundation of China, No.40235053 No.40401012+1 种基金 AIACC, No.AS25 Lanzhou Jiaotong University Foundation
文摘Northwest China includes Xinjiang Ugyur Autonomous Region, Qinghai Province, Gansu Province, Ningxia Hui Autonomous Region and Shaanxi Province, covering 308×10^4km^2. It is located in the warm-temperate zone and the climate is arid or semi-arid. Precipitation is very scarce but evaporation is extremely high. The climate is dry, the water resources are deficient, the ecoenvironment is fragile, and the distribution of water resources is uneven. In this region, precipitation is the only input, and evaporation is the only output in the inland rivers, and precipitation, surface water and groundwater change with each other for many times, which benefits the storage and utilization of water resources. The average precipitation in this region is 232 mm, the total precipitation amount is 7003×108m^3/a, the surface water resources are 1891×10^8m^3/a, the total natural groundwater resources are 1150×10^8m^3/a, the total available water resources are 438×10^8 m^3/a, and the total water resources are 1996×10^8m^3/a and per capita water resources are 2278 m^3/a. The water resources of the whole area are 5.94×10^4m^3/(a.km^2), being only one-fifth of the mean value in China. Now, the available water resources are 876×10^8m^3/a, among which groundwater is proximate 130×10^8m^3/a.
文摘Based on affirming the tremendous benefits that water resources of rivers can provide in their exploitation, main environmental problems and their countermeasures have been proposed and analyzed in this paper. It is argued that multiple measures should be applied to solving those problems by simultaneously carrying out engineering measures, scientific research and also programs to cultivate the society’s awareness, aimed at a sustainable development strategy for exploiting water resources.
基金This study was supported by National Natural Science Foundation of China with grant number! 49890330-4-2 and 49671013
文摘In shallow groundwater agricultural fields, water exchanges between groundwater and soil water happen frequently and intensively. This paper analyzes the regale of subsurface water during the growing period of winter wheat from October 1998 to June 1999 in Yucheng area. During an 8- month period of winter wheat growth. 456.66 mm of evapotranspiration and 75.61mm of groundwater evaporation were measured with a new model lysimeter. Groundwater at 1.60-2.40 m depth of water tables contributed 16.6% of total water used by winter wheat under natural. precipitation and irrigation treatment.The results showed that a significant proportion of field evapotranspiration was supplied by groundwater evaporation, whereas the role of groundwater evaporation was not considered during irrigation, leading to soil water percolation into groundwater.In order to improve water use efficiency of crops, some measures were put forward in the paper. Effective use of groundwater and soil water is a key countermeasure for sustainable development of water-saving agriculture and Water resource exploitation in Yucheng area