| Lake is the main water resource in arid and dry areas, is an indicator of climate change in the region, meanwhile,is also an important component of the water cycle in arid andsemi-arid areas, is an important information carrier of climate change and regional response,Therefore,its formation and disappearance,expansion and contraction has beena hot topic of scientific research.In this paper, based on field survey and collecting relevant data, through using isotopic methods and hydrogechemical methods,we have studied isotopic characteristics and hydrogechemical characteristics of bosten lake, studied isotopic characteristics and hydrogechemical characteristics of river water, studied isotopic characteristics and chemical characteristics of groundwater.The main results are as follows:(1)18 water samples in different water bodies, including river, groundwater and lake in the Bosten Basin were collected in October 2014. Their δD and δ18O vales were measured. The results indicate that: the Bosten Lake mean value of the δD is about-0.36‰,that of the δ18O is for-15.98‰, and with relationship of δD=2.99δ18O-14.91; the river water mean value of the δD is about- 61.81‰, δ18O is for-9.23‰,shows the relationship of δD=6.1δ18O- 5.43; the groundwater mean δ18O value is about-8.11‰,δD is for- 57.01‰, shows the relationship of δD=4.61δ18O- 19.68. The datum of river water, lake water and groundwater are all distributed around the Graig(1961) global and local meteoric water line in δ18O-δD coordinate system.It shows the characteristic of precipitation water. When Comparison our result with previously works, it shows differences. Although it may related to local temperature,precipitation and human activities, we proposed that it should caused by sample distribution difference.(2)The dominant ions of the river, lake and the groundwater were Na+, SO42- and Cl-. The concentrations of the major ions were showing the order of Kaidu River >Bosten Lake>groundwater. From upstream to downstream of the river: The TDS and conductivity were increased. Cl- was continued to decrease. K+, Na+ and SO42- increased in the middle reaches, and then reduced along the river. The contents of Cl- and SO42- changed significantly, while Mg2+ and Ca2+ were relatively stable.The cations concentration was in the order of Na+>Mg2+>Ca2+>K+ while that for anions was SO42->Cl->NO3- both in the Lake and the small washes around it. The concentrations of Ca2+, Mg2+ and Na+ i.e. in the small washes were significantly higherthan those in the main lake. On the contrast,Cl-, NO3- and SO42- i.e. in the main lake were significantly higher than those in the small washes. For nearly half a century, the ionic concentrations in the Bosten Lake were significantly increased by 7.4 times, and especially, the SO42-concentration was as high as 14.83 times that in 1958. Human activities had significant influence on the geochemistry of major ions in the water.The study had important significance for the change of river hydrochemistry, water quality characteristics and water quality protection of rivers and lakes in the arid area of Northwest China.(3)through using inverse distance weighted(IDW) interpolation methods,studied Spatial distribution of δD and δ18O of lake water in the Bosten Lake.The results shows that the Spatial distribution of δD and δ18O in the Bosten Lake is not balance.overall,the Spatial distribution of δD and δ18O in bosten lake tendency is from west to east;This is closely related with the main sources of supply,water quality and water evaporation intensity. |
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