傍河水源地的水动力过程和水质作用机理及其对开采条件的响应

The capacity of regulation and storage and the effect of water quality improvement of riverside well field are two essential problems concentrated on by engineering practices, which are also difficulties in scientific research. During the past years, these two problems become research hotspots mainly because of the highlight of water resources and water environment problems. An experimental riverside well field along the Songhua River near Harbin City is selected as the study area in this study. Based on the previously completed works on hydrogeological investigation and trial test study, the hydrodynamics processes will be characterized by coupling using analytical method and numerical method. Then, modeling and prediction of the impacts of different exploiting layouts and programs on hydrodynamics and water quality will be carried out. In the meantime, corresponding works of indoor sand filter tank experiment are also proceeded. These works are followed by empirical study and corresponding improvement of the established models through field pumping tests. Finally, mechanisms of hydrodynamic processes and water quality effects of riverside well field and their responses to different exploiting programs will be revealed, which are primarily dependent on repeatedly field pumping tests and reduplicative model debugging. Findings of this study are not only helpful in constructing riverside well field in area with high groundwater Fe, Mn and ammonia nitrogen, but also meaningful to regulation of groundwater hydrodynamics by using optimizing exploiting layouts and programs, which are decisive effect on water quality improvement deservedly followed by lowering water treatment cost.

傍河水源地的水量调蓄能力和水质改善效果是工程实践中关注的焦点，但也一直是研究的难点，并且在近些年随着水资源和水环境问题的凸显而成为研究热点。本项目以松花江哈尔滨段一处试验傍河水源地作为研究场地，在已开展的水文地质勘察和预试验研究工作等的基础上，联合应用解析法和数值法建立模型对水动力过程进行刻画，并对不同开采井布局和开采方案对水动力和水质的影响进行模拟预测。同时开展室内渗流槽模拟试验对水质作用及其机理进行揭示。在此基础上开展抽水试验进行实证研究并据此对已建模型进行改进。通过多次抽水试验和对模型进行反复调试，以揭示该非完整河流型傍河水源地的水动力过程和水质作用机理及其对不同开采条件的响应。该研究对于在存在区域性地下水铁、锰、氨氮偏高问题的地区建设傍河水源地，以及如何通过优化设计开采井布局和开采方案等来对地下水水动力条件进行调控，进而改善出水水质从而降低水处理成本具有非常重要的意义。

傍河水源地的水量调蓄能力和水质改善效果是工程实践中关注的焦点，也一直是科学技术研究的难点。本项目以松花江哈尔滨段一处试验傍河水源地作为研究场地，在水文地质勘察和预试验研究工作等的基础上，联合应用抽水试验法、解析法和数值法等对傍河水源地的水动力过程进行了刻画，并对不同开采井布局和开采方式对水动力和水质的影响进行了研究，同时开展室内控制试验对水质作用及其机理进行了揭示。在此基础上开展抽水试验进行实证研究并据此对已建模型进行了改进。通过多次抽水试验和对模型进行反复调试，以揭示该河流非完整切割型傍河水源地的水动力过程和水质作用机理及其对不同开采条件的响应。研究结果显示，开采条件下能够很快形成比较稳定的地下水水位降落漏斗，使开采井能够持续地得到江水的补给，从而能够保证可持续开采。由于能够及时得到江水的补给，开采井及其周边地区不会发生持续性的地下水水位下降。开采井抽水导致的江水渗漏量只占江水流量的很小一部分，因此傍河取水对江水的水资源和河流生态环境的影响甚微。岸滤系统对江水中的内分泌干扰物起到了非常好的净化作用，可以完全去除；对浊度、硝酸盐、硫酸盐等指标也有着很好的净化效果，去除率可以达到50%以上。实验场地的原生地质环境条件（属于区域性问题）对水质提升作用有一定的制约作用，使铁、锰、氨氮等水质指标的提升效果受到影响。地下水与地表水相互转化过程中受到地表水-地下水交错带中各种物理（械过滤、挥发和稀释作用）、化学（吸附、水解、光解、溶解、沉淀、络合、多组分溶质的反应等）和生物（微生物降解和酶催化）作用的影响，从而影响着水化学成分的分布和演化规律。研究目标已全面完成，研究成果为傍河水源地的供水安全提供了重要科学依据，也进一步推动了地表水-地下水相互作用研究工作。相关研究成果已在Science of the Total Environment、Environmental Pollution、Hydrological Processes等期刊发表论文15篇，其中SCI收录13篇，中文核心期刊2篇。