摘要
通过对2006～2008年锡林河主要径流期内13个河水断面239个水样以及同期地下水和大气降水主离子水化学进行分析，结合锡林河流域的气象和水文资料，利用Piper三线图和Gibbs图分析了锡林河河水的水化学特征及主离子组成变化特征．结果表明，锡林河河水TDS变化范围在136．7～376．5mg·L^-1之间，平均245．1mg·L^-1，为低矿化度河水；河水中主要阳离子以Ca2＋为主，阴离子以HCO3^-为主，河水的水化学类型从HCO3-—Ca2＋过渡到HCO3--Ca2＋·Mg2＋；河水主离子平均浓度年内、年际变化均不大，年内变化表现在5月主离子浓度高于其他月，年际变化表现为主离子在2007年的平均浓度均较小；空间上，Ca2＋、Na＋、Mg2＋、K＋、Cl^-和HCO3^-的浓度呈现沿程逐渐增加的趋势，SO4^2-的浓度变化呈先增加后减小的趋势；河水中主离子浓度值介于大气降水和地下水之间，并且十分接近地下水浓度，说明地表水同时受大气降水和地下水补给并主要依靠地下水补给；Gibbs图显示河水离子组成主要与流域内的岩石风化有关，流域有一定量的蒸发岩存在，但蒸发岩对水化学的贡献弱于碳酸盐岩．
Under the increasing pressure of water shortage and steppe degradation, information on the hydrological cycle in the steppe region in Inner Mongolia is urgently needed. Major ions are widely used to identify the hydrological processes in a river basin. Based on the analysis results of 239 river water samples collected in 13 sections along the Xilin River system during 2006 to 2008, combined with data from groundwater and precipitation samples collected in the same period and the meteorological and hydrological data in the Xilin River Basin, hydrochemical characteristics and the chemistry of major ions of the Xilin River water have been studied by means of Piper triangle plots and Gibbs diagrams. The results showed that： （1）the total dissolved solid （TDS） in river water mainly ranged between 136.7 mg·L^-1 and 376.5 mg·L^-1 , and （2） it had an increasing trend along the river flow path. （3）The major cations and anions of river water were Ca2＋ and HCO3- , respectively, and the chemical type of the river water varied from HCO3- -Ca2＋in the headwater area to HCO3- -Ca2 ＋ · Mg2 ＋ in the lower part. （4） The variation in the concentration of major irons in surface water was not significant at the temporal scale. Usually, the concentration values of major irons were much higher in May than those in other months during the runoff season, while the values were a bit lower in 2007 than those in 2006 and 2008. Except for SO42- , the concentrations of other ions such as Ca2＋ , Na ＋ , Mg2＋, K ＋ , Cl- and HCO3- showed a upward trend along the river flow path. Comparing major ion concentrations of the river water with those of local groundwater and precipitation, the concentration in river water was between those of precipitation and groundwater but was much closer to the concentration of groundwater. This indicated that the surface water was recharged by a mixture of precipitation and groundwater, and groundwater showed a larger impact. The Gibbs plot revealed that the chemical compositions of the river water were mainly affected by rock weathering in the drainage area.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2014年第1期131-142,共12页
Environmental Science
基金
国家自然科学基金项目(41271085)
中德合作项目(German Science Foundation(DFG)
FG 536)
关键词
主离子
地表水
水化学
时间变化
空间变化
锡林河流域
major ions
surface water
hydrochemistry
temporal variation
spatial variation
Xilin River Basin
