内蒙古土默川平原地下水化学季节性变化特征  

Seasonal changes of groundwater chemistry in Tumochuan Plain of Inner Mongolia

作　　者：刘白薇[1] 董少刚 唐仲华[1] 夏蔓宏 Liu Baiwei;Dong Shaogang;Tang Zhonghua;Xia Manhong(School of Environment,China University of Geosciences(Wuhan),Wuhan 430074,China;College of Ecology and Environment,Inner Mongolia University,Hohhot 010021,China)

机构地区：[1]中国地质大学(武汉)环境学院,武汉430074 [2]内蒙古大学生态与环境学院,呼和浩特010021

出　　处：《工程勘察》2020年第5期34-40,共7页Geotechnical Investigation & Surveying

基　　金：国家自然科学基金(41562020,41002129);内蒙古自然科学基金(2018MS04004)。

摘　　要：通过水文地质调查并结合采样分析,研究了内蒙古托克托县地区地下水水质随季节变化的特征机理。结果表明:大气降水的偏酸性导致丰水期地下水pH值降低;季节变化对本区地下水TDS影响主要表现为丰水期的稀释淋溶作用和枯水期的蒸发浓缩作用。丰水季节随降水进入地下水中的CO2促使含水介质中的硅铝酸盐发生水解,使部分区域HCO3-浓度明显升高。雨季溶解氧随降水补给地下水,氧化富含硫化物的矿物或有机质,会使地下水中的硫酸盐浓度升高;在枯水季节,随着溶解氧的消耗,部分硫酸盐参与有机物的氧化分解,本身被还原,导致其浓度降低。在地下水位埋深浅、农牧业活动剧烈的区域,地表的污染物容易随降水进入含水层,使地下水的CODMn浓度分布随季节发生明显的改变。Through hydrogeological survey and sampling analysis,the mechanism of groundwater quality changing with seasons is studied in Tuoketuo County of Inner Mongolia.The results show that the acidity of atmospheric precipitation leads to the decrease of the pH value of groundwater in wet season;the effects of seasonal changes on groundwater TDS in this area are mainly manifested by the dilution leaching during the wet season and the evaporation and concentration during the dry season;during the wet season,the CO2 entering the groundwater with precipitation promotes the hydrolysis of aluminosilicate in the water-bearing medium,which significantly increases the concentration of HCO3-in some regions;during the rainy season,dissolved oxygen replenishes groundwater with precipitation,and oxidizes sulfide-rich minerals or organic matters,which will increase the concentration of sulfates in groundwater;in the dry season,with the consumption of dissolved oxygen,some sulfates participate in the oxidative decomposition of organic matter,results in a reduction in their concentration;in areas where the groundwater level is shallow and the agricultural and livestock activities are intense,the surface pollutants are easy to follow.Precipitation enters the aquifer,causes the CODMnconcentration of the groundwater to change significantly with the season.

关 键 词：水岩相互作用 脱硫酸作用 淋滤 稀释 土默川平原 

分 类 号：X523[环境科学与工程—环境工程] TU46[建筑科学—结构工程]