United Nations University, Institute for Integrated Management of Resources and Material Fluxes (UNU-FLORES), Ammonstraße 74, 01067 Dresden, Germany; Technische Universität Dresden, Institute for Groundwater Management, 01069 Dresden, Germany.
United Nations University, Institute for Integrated Management of Resources and Material Fluxes (UNU-FLORES), Ammonstraße 74, 01067 Dresden, Germany.
Sci Total Environ. 2018 Sep 15;636:1089-1098. doi: 10.1016/j.scitotenv.2018.04.347. Epub 2018 May 3.
Wastewater irrigation is a common livelihood practice in many parts of the developing world. With the continuous irrigation supply, groundwater systems in these regions perceive adverse impacts due to inadequate infrastructure to treat the wastewater. The current study area, Musi River irrigation system, is one such case study located in the peri-urban Hyderabad of South India. The Musi River water, which is used for irrigation, is composed of untreated and secondary treated wastewater from Hyderabad city. Kachiwani Singaram micro-watershed in the peri-urban Hyderabad is practicing wastewater irrigation for the last 40 years. The current quality of (untreated) wastewater used for irrigation is expected to have adverse impacts on the local aquifers, but detailed investigations are lacking. To elucidate the groundwater quality dynamics and seasonality of the wastewater irrigation impacts on the peri-urban agricultural system, we analyzed the groundwater quality on a monthly basis for one hydrological year in the wastewater and groundwater irrigated areas, which exist next to each other. The spatio-temporal variability of groundwater quality in the watershed was analyzed with respect to wastewater irrigation and seasonality using multivariate statistical analysis, multi-way modeling and self-organizing maps. This study indicates the significance of combining various statistical techniques for detailed evaluation of the groundwater processes in a wastewater irrigated agricultural system. The results suggest that concentrations of the major ionic substances increase after the monsoon season, especially in wastewater irrigated areas. Multi-way modeling identified the major polluted groundwaters to come from the wastewater irrigated parts of the watershed. Clusters of chemical variables identified by using self-organizing maps indicate that groundwater pollution is highly impacted by mineral interactions and long-term wastewater irrigation. The study recommends regular monitoring of water resources and development of sustainable management strategies to mitigate the aquifer pollution in wastewater irrigation systems.
污水灌溉是许多发展中国家常见的生计实践。由于缺乏处理污水的基础设施，这些地区的地下水系统受到了持续灌溉供应的不利影响。当前的研究区域，Musi 河流域灌溉系统，是印度南部海得拉巴市周边的一个这样的案例研究。用于灌溉的 Musi 河水由海得拉巴市未经处理和二级处理的废水组成。海得拉巴市周边的 Kachiwani Singaram 小流域已经进行了 40 多年的污水灌溉。目前用于灌溉的未经处理污水的质量预计会对当地含水层产生不利影响，但缺乏详细的调查。为了阐明地下水质量动态和污水灌溉对城郊农业系统的季节性影响，我们在一个水文年内每月对相邻的污水和地下水灌溉区的地下水质量进行了分析。使用多元统计分析、多向建模和自组织映射分析了流域内地下水质量的时空变异性与污水灌溉和季节性的关系。这项研究表明，结合各种统计技术对于详细评估污水灌溉农业系统中的地下水过程具有重要意义。结果表明，主要离子物质的浓度在季风季后会增加，特别是在污水灌溉区。多向建模确定了主要受污染的地下水来自流域的污水灌溉部分。自组织映射识别的化学变量聚类表明，地下水污染受到矿物相互作用和长期污水灌溉的高度影响。该研究建议定期监测水资源并制定可持续管理策略，以减轻污水灌溉系统中的含水层污染。
