Study On Salinization And Groundwater Control Measures Of Keleya Oasis

The reasonable and effective regulation of the groundwater is an important part of theground water and salt movement law，but also one of the important method of prevention of siolsalination. Soil salination is a direct result of the decline in land productivity，crop output rate，it has become increasingly serious major issues facing today＇s society of agricultural production.Under this background，in the context，through the field survey and research in the variousvillages and towns within the keleya Oasis，gaining the underlying data，and using a theoreticalcalculationgs way of a combination of classical statistics and geostatistics，and field-proven，initially proved regional groundwater depth， shallow groundwater dynamic reserves andsalinization of the type and extent. On the basis of the proposed groundwater control measures，drainage way out and saline land treatment of other types of measures，so as to provide thetheory and practical experience support to the arid area of oasis agricultural production，ecological restoration，water resources＇s rational and efficient use and regional sustainabledevelopment.Initially formed the following conclusions：1. The coefficient of variation of Groundwater depth of the study area is great than30%，belong to the strong variation. By single-sample Kolmogorov-Semirnov （K-S） test and foundtheir values follow a normal distribution，in line with the requirements of geostatistics andsemi-variance model，and it is fitted with Gaussian model.2. The groundwater depth and the spatial characteristics of the mineralization degree showthe opposite trend from south to north on the terrian，the groundwater depth becomes smaller，while the groundwater salinity is gradually increasing trend. The seasonal changes ofgroundwater depth is obvious，the groundwater depth changes generally lag behind changes inthe amount of surface water runoff and irrigation.5～9months for the high-water period，October to April the following year for the low-water period，dynamic changes in groundwaterdepth trends were as follows：began to rise in march，the groundwater depth reached the highest in may，and then began to deline，maximum depth after September，then the groundwater depthbegan to rise.3. Seasonal changes in groundwater quality（salinity，TDS）showing：began to decline inmarch，reached the highest in september，and then began to rise slowly，significant seasonalvariation. The reason of Groundwater environment change is due to the impact of the study area，agricultural irrigation，the infiltration of local irrigation is extraction of groundwater to irrigatepart of the irrigation return flow，resulting in the increase of the ion cotent of shallowgroundwater；Water chemistry characteristics in turn of Cl+SO4+Na and HCO₃+SO₄+Na+Mg；Lower part of the water chemistry type is HCO₃+Cl+Na。Hydrochemistry of the groundwaterfollows the law of the arid zone of groundwater migtation. PH>8.0，indicating that the soil isalkaline； Generally，each ion decreases with increasing soil depth.4. Total water resources of the keleya oasis is basically out of the Yamaguchi river runoff andpiedmont groundwater lateral seepage sum，the total water resources of about10.787×10⁸m³，of which the surface water of the keleya river basin is10.477×10⁸m³，natural groundwaterrecharge is0.310×10⁸m³. The keleya basin groundwater composed from two parts of thepiedmont lateral recharge of0.310×108m3and plain areas of precipitation recharge，plaindistrict，very little precipitation and strong evaporation，recharge the formation of very unstable，most fo year can not form the supply，it actually should only consider the piedmont lateralrecharge of0.310×10⁸m³，so that the natural groundwater recharge of the basin，that is，groundwater resources in the real sense of only0.310×10⁸m³.5. Keleya River Basin into the groundwater amount of3.64×10⁸m³，natural groundwaterrecharge is0.310×10⁸m³，groundwater resources of natural groundwater recharge and conversionrecharge groundwater together is3.95×10⁸m³，natural groundwater recharge and conversionrecharge，respectively，7.85%，92.15%of the total recharge. Should be noted that this value is onlya general sense of groundwater resources，rather than the true sense of the“resources”. Largenumber of the repeated measures of the transformation of water resources，the use of groundwateris necessary and meaningful. But we must have a clear concept，such sa taking the channel seepage control measures to improve water use efficiency，is to reduce the transformation of waterresources on the repeated measures；as the construction of water to tap underground water，and useof water resources into the repeated measures. However，both of which can not increase the waterresources utilization.6. By the analysis of Water balance，to better reflect the relationship of the conversion andsupply of surface water and groundwater，to provide a theoretical basis for the use anddevelopment of surface water and groundwater. Through short-term and long-term salt and waterbalance calculation and analysis show that：the irrigation area in the state of the salt accumulation，the average irrigation area salt accumulation19.00×10⁴T. Long term planning related projects tobe implemented，such as strengthening the water-saving irrigation measures to improve thedrainage system，irrigation district per year will be able to achieve desalination annual desalination19.83×104T，desalination of pre-main irrigation area historical salt accumulation gradually cameto the irrigation area terrain Order of the lower northern desert vent area，then the irrigation area toachieve the water and salt balance，and will enable the project area salinity dynamics in theconversion to a virtuous circle. Salt and water balance analysis，and salt drainage needs，dischargeof groundwater outside the District in the planning period is not less than1.05×10⁸m³. inaccordance with diving evaporation scale （1.77×10⁸m³），irrigation drainage scale （1.05×10⁸m³），groundwater exploitation in the initial size （1.20×10⁸m³） and the implementation of the project，This estimate is less than2.0m shallow groundwater drawdown of1.26m，can achieve the requiredagricultural areas critical depth of groundwater depth.7. The row with the actual salt according to the irrigation district agricultural drainage，groundwater control measures to determine the measures for the next row and well ranked，andinitially set out to row the project，including dry row6，row38， he electromechanical wellsscale of350. drainage of the discharge area were the introduction of the irrigation area innorthern desert area and the row Rukeliya River river.