摘要
This study aimed to evaluate the spatial and temporal variations of molybdenum(Mo)in the downstream water body of a Mo mine during three hydrologic periods(wet,dry and medium seasons).The physical properties in Luhun Reservoir reflected seasonal variations in different hydrological periods.The redox potential(ORP)and dissolved oxygen(DO)increased in the dry season.The concomitant decrease in temperature(T),conductivity(COND)and total dissolved solids(TDS)were lowest in the wet season.The p H value did not change significantly during the three hydrologic periods.The distribution of Mo in the dry season was high in upstream and low in downstream areas,which was significantly different from that of the wet and medium seasons.The total Mo concentration in wet(150.1μg/L)and medium season(148.2μg/L)was higher than that in the dry season,but the TDS(288.3 mg/L)and the percentage dissolved Mo(81.3%)in overlying water was lowest in the wet season.There was no significant relationship between the dissolved Mo and the total Mo with TDS.In the dry season,the mean total Mo concentration was 116.3μg/L,which was higher than the standard limit value(70μg/L)for drinking water(US EPA-United States Environmental Protection Agency recommended value 40μg/L).Non-point source pollution is the main characteristic of mining area pollution,which was closely related to rainfall.Thus,the Luhun Reservoir contains substantial Mo pollution,which was a significant concern given that it is used as a source of drinking and irrigation water.
基金
supported by the National Natural Science Foundation of China(Nos.41701546 and 41877368)
the Youth Innovation Promotion Association CAS(No.2017059)
the Key Scientific Research Project of Colleges and Universities of the Henan Education Department(No.17A570001)
the North China University of Water Resources and Hydropower Research Project for highlevel talents。
