Three Stages of the Groundwater Chemical Properties Reacting on the Intermittent Water Deliveries in Lower Tarim River,China
塔里木河下游地下水化学特征对输水响应的阶段性研究

Based on the monitored data of groundwater chemical properties and groundwater depth influenced by five intermittent water deliveries in the lower reaches of the Tarim River,the regulation of groundwater chemistry varying was analysed,the variations in groundwater chemical properties unfolded a clear threestages changing character under the influence of water deliveries: the initial stage-concentrations of major ions and total dissolved solids(TDS) increasing; the intermediate stage-the concentrations decreasing;the late stage-the chemical properties increasing once more.The variation of groundwater chemistry resulted from many factors,such as the salinities in soil profile,the quality of transported water,the distance from watercourse,the amount and the season of the delivery.However,"salts coming with the water flow,and leaving with it" is the main reason that led to the increase and decrease of chemical properties at first stage and second stage,and with the uprising water level,more and more salinities in soil profile dissolved into ground water and the severe evaporation resulted the concentrations of major ions and TDS increase at late stage.Furthermore,the variations of groundwater chemistry at the intermission of water deliveries have close relationship to the three stages.It should be pointed out that the mode of water transport in surface scope is infeasible due to the climate characteristics of the lower reaches of the Tarim River.