| Chahaertan Oasis is located on the edge of the Ulan Buh Desert, and it is one of the topten agricultural irrigation area of Alxa League. The oasis has arid climate, scarce precipitation,intensive evaporation, and fragile ecological environment. Groundwater is the only source ofwater in Chahaertan Oasis, and it is the most important factor to maintain the production andlife of local residents. However, due to the lack of scientific management of groundwater,excessive groundwater exploitation, there are some problems with varying degrees inIrrigation techniques and crop planting structure, and it lead to the problems such asgroundwater tables declining year by year, water quality degradation and soil salinization inoasis. Ecological protection and agricultural development of oasis are under serious threat.Chahaertan Oasis with area of27.7km2, and the problems in the process of utilization ofgroundwater resources in which have the typical of groundwater resources research of thenorthwest arid desert oasis.Through the research methods of field investigation combined with field test, the statusof development and utilization of groundwater resources and the groundwater dynamicwere investigated, and the groundwater resources carrying capacity of oasis was determinedand then the suggestions on the sustainable utilization of groundwater resources wereproposed. The main results of this paper are as follows:(1) The observational data of groundwater regime indicate that the cumulative drawdownof single well of observation wells had reached the depth of6-10meters and a decline of0.27-0.45meters in average annual; The embedded depth of groundwater level of62observation wells of Jilantai lake-basin changed in the range of0.2-1.17meters. It means thatgroundwater withdrawal is greater than the recharge. The use of groundwater resourcesbelongs of the type of consumed-runoff, and it’s in a non-stable-dewatering process.(2) Agricultural structural adjustment is given priority to corn and oil sunflower in theoptimized configuration scheme. Corn acreage change from982.4hm2of status quo to150.33hm2in2015,151.13hm2in2020and153.8hm2in2025. Oil sunflower acreage change from 223.3hm2of status quo to718.4hm2in2015,855.47hm2in2020and829.73hm2in2025.Groundwater withdrawal of oasis decrease from20million m~3/a of status quo to7.029millionm~3/a in2015,7.029million m~3/a in2020and6.548million m~3/a in2025.(3) There is an analysis of the result of agricultural structure of configuration schemefrom the perspective of agricultural virtual water, and we obtained that the virtual watercontent of spring wheat, spring corn, oil sunflowers melons and vegetables respectively was800m~3/t,460m~3/t,776m~3/t,62m~3/t,66m~3/t by calculating. And then we obtained the totalof virtual water content of the present year respectively was4706191m~3,5231209m~3and5321888m~3, which was different of planned annual of7274038m~3,and the result verify theresults of the rationality and reliability of agricultural structure.(4) We made a further study on the groundwater sustainable use in Chahaertan Oasis, andthen put forward some measures of exploiting groundwater based on the sustainabledevelopment:①Desert oasis should decide agriculture by water and decide development bywater and compress cultivated area of agriculture and adjust crop-planting structure;②Tostrengthen groundwater management and control the amount of groundwater mining;③Toformulate reasonable irrigative system, and transform backward irrigative way, to employhigh-effectively water-saving irrigative method. Meanwhile, the special analysis of thetechnology of introducing high yield water-saving crops and the technology of water-savingirrigation shows that: the introduction of cotton and millet-based high yield water-savingcrops and implementing the technology of drip irrigation under film has high economic andecological benefits in Chahaertan Oasis. It is feasible to extend. |
PDF Full Text Request