Department of Biological Sciences, Faculty of Science, Yarmouk University, Irbid, 21163, Jordan.
Department of Earth and Environmental Sciences, Faculty of Science, Yarmouk University, Irbid, 21163, Jordan.
Environ Monit Assess. 2019 Feb 9;191(3):153. doi: 10.1007/s10661-019-7292-8.
The purpose of this study is to examine the impact of treated wastewater irrigation on agricultural soils and vegetables along the upper reach of Zarqa River (Jordan). Multiple samples of reclaimed wastewater, soil pits from farms, and vegetables (spinach, parsley, cabbage cauliflower, radish, and onion) were collected and analyzed for pH, total dissolved solids (TDS), and/or NO and NO contents. The average levels of NO and NO in treated wastewater samples varied from 167.2 to 209.9 mg/l for NO and from 80.3 to 106.1 μg/l for NO. Values of TDS and pH exhibited relatively comparable spatial patterns, with higher values in the downstream channel and lower in the upper reach, adjacent to Al-Samra Wastewater Treatment Plant. The average values of NO and NO showed broadly decreasing trends down-gradient towards King Talal Dam. In soil pits, a marginal increase of pH values with depth was noted, whereas TDS showed a remarkable decrease in soil profile by ~ 2 to 3 folds. Concurrently, the levels of NO and NO in all soil pits markedly decreased from top to bottom. In vegetables irrigated with treated wastewater, substantially elevated levels of NO were observed, compared with those irrigated with rainwater, with leafy vegetables demonstrating higher levels than the root crops. Spinach exhibited higher capacity for NO accumulation (4614.1 mg/kg), while onion showed the lowest content (1722 mg/kg). The highest NO level was observed in parsley (1.19 mg/kg), and the lowest concentrations were found in cauliflower (0.25 mg/kg). The markedly high accumulation of NO in vegetables is an indicator of pollution activities around Zarqa River and poses potential health risks to humans when they are consumed.
本研究旨在探讨经处理废水灌溉对扎尔卡河上游农业土壤和蔬菜的影响。采集了再生废水、农场土坑和蔬菜（菠菜、欧芹、白菜、花椰菜、萝卜和洋葱）的多个样本，并对其 pH 值、总溶解固体（TDS）和/或硝酸盐和亚硝酸盐含量进行了分析。处理后废水中硝酸盐和亚硝酸盐的平均含量分别为 167.2-209.9mg/L 和 80.3-106.1μg/L。TDS 和 pH 值的变化呈现出相对可比的空间模式，下游河道的数值较高，而靠近 Al-Samra 污水处理厂的上游河道数值较低。硝酸盐和亚硝酸盐的平均含量呈向下游国王塔勒大坝逐渐降低的趋势。在土坑中，随着深度的增加 pH 值略有增加，而 TDS 在土壤剖面中显著降低了 2-3 倍。同时，所有土坑中硝酸盐和亚硝酸盐的含量从上到下都明显降低。在使用处理后的废水灌溉的蔬菜中，硝酸盐的含量明显高于雨水灌溉的蔬菜，叶菜类蔬菜的硝酸盐含量高于根茎类蔬菜。菠菜对硝酸盐的积累能力最高（4614.1mg/kg），而洋葱的含量最低（1722mg/kg）。 parsley 中的硝酸盐含量最高（1.19mg/kg），花椰菜中的硝酸盐含量最低（0.25mg/kg）。蔬菜中硝酸盐的高度积累表明扎尔卡河流域附近存在污染活动，食用这些蔬菜可能对人体健康造成潜在威胁。
