| 引用本文: | 姜欣,朱林,许士国,谢在刚.水源水库季节性分层及悬浮物行为对铁锰迁移的影响——以辽宁省碧流河水库为例.湖泊科学,2019,31(2):375-385. DOI:10.18307/2019.0207 |
| JIANG Xin,ZHU Lin,XU Shiguo,XIE Zaigang.Effects of seasonal stratification and suspended sediment behaviors on the mobilization of manganese and iron in a drinking water reservoir-A case of Biliuhe Reservoir, Liaoning Province. J. Lake Sci.2019,31(2):375-385. DOI:10.18307/2019.0207 |
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| 摘要: |
| 铁和锰是氧化还原敏感的元素，水源水库热分层引起的底层水体缺氧造成了沉积物中铁和锰的释放，对城市供水造成了极大的影响.以往鲜有悬浮物行为对铁和锰在水库水-沉积物界面迁移影响的研究，于2014年2月-2015年2月对碧流河水库深水区的水、悬浮物以及沉积物铁和锰的垂向分布特征进行综合调查分析，并进一步分析铁和锰的季节性变化规律及悬浮物行为对其的影响.Spearman相关分析结果表明铁浓度与总悬浮固体、总氮和总磷的相关性较大；锰浓度与总悬浮固体、溶解氧、pH和总氮的相关性较大.进一步讨论分析表明碧流河水库的热分层、底层缺氧以及沉积物再悬浮是影响铁和锰浓度的重要因素，水库铁和锰的季节变化规律存在差异.分层期溶解态的锰在底层累积，平均浓度达到0.18 mg/L，而沉积物中溶解态的铁释放很少.混合期水库的中上层锰浓度升高，达到了0.07 mg/L.沉积物的再悬浮是水库底层水体中铁的主要来源，底层颗粒态铁的平均浓度约为0.3 mg/L.絮凝的颗粒物以及其吸附的锰在水库长期悬浮，难以沉积到水库底部，使得悬浮物中Mn的含量显著高于表层沉积物，约为沉积物的7倍.建议应在碧流河水库采用分层取水、水库曝气以及联合供水等措施，以减少铁和锰的浓度升高对供水产生的影响，保障大连市城市供水安全. |
| 关键词: 铁 锰 悬浮物 分层 水源水库 碧流河水库 |
| DOI：10.18307/2019.0207 |
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| 基金项目:国家自然科学基金项目（51327004）资助. |
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| Effects of seasonal stratification and suspended sediment behaviors on the mobilization of manganese and iron in a drinking water reservoir-A case of Biliuhe Reservoir, Liaoning Province |
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JIANG Xin1, ZHU Lin1, XU Shiguo1, XIE Zaigang2
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1.Institute of Water and Environmental Research, Faculty of Infrastructure Engineering, Dalian University of Technology, Dalian 116024, P. R. China;2.Management Bureau of Biliuhe Reservoir, Dalian 116221, P. R. China
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| Abstract: |
| Iron and manganese are both redox-sensitive elements and important chemical indicators of drinking water quality. The anaerobic hypolimnion caused by thermal stratification results in the release of iron and manganese from sediments in water-supply reservoirs. The exceeding concentration of them may have a great impact on urban water supply. Little research has focused on the relationship between suspended sediment behaviors and the mobilization of iron and manganese in the water-sediment interface of reservoirs. To demonstrate the seasonal variation of iron and manganese and the influence of suspended matter on its behavior in the Biliuhe Reservoir, we comprehensively investigated and analyzed the vertical distribution characteristic of iron and manganese in water, suspended sediments, and sediments from February 2014 to February 2015. According to the results of Spearman correlation analysis, the concentration of iron is highly correlated with total suspended solids, total nitrogen, and total phosphorus, while, the concentration of manganese is significantly correlated with total suspended solids, dissolved oxygen, pH and total nitrogen. Further analysis results indicate that the thermal stratification, the anaerobic hypolimnion, and the resuspension of sediments significantly affect the concentration of iron and manganese in the Biliuhe Reservoir. The average dissolved manganese concentration accumulates on the bottom layer to 0.18 mg/L in the stratified season, while the dissolved iron releases very little from the sediment. The manganese concentration of the surface and middle layers increase to 0.07 mg/L in the mixing season. Because the average concentration of particulate iron in the bottom layer is approximately 0.3 mg/L, the resuspension of sediments may be the main iron source in the bottom layer of the Biliuhe Reservoir. In addition, the flocculated particulate matter and its adsorbed manganese could stay in the reservoir for a long time, so that the content of manganese in the suspended matter is about 7 times higher than that in the surface sediments. Thus, to reduce the impact of elevated iron and manganese concentrations on water supply in the Biliuhe Reservoir, the most effective management practices focused on multi-level intake, hypolimnetic aeration, and amalgamated waterworks, which could ensure the safety of urban water supply in Dalian. |
| Key words: Iron manganese suspended sediment stratification drinking water reservoir Biliuhe Reservoir |
