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1.
The concern related to the drinking of reverse osmosis (RO) water containing low levels of minerals is growing day by day. This study involves the analysis of water samples from various drinking water sources in a rural site, Mirchpur village, an Indus Valley civilization site (grid location: 29° 18′ 42.3″ N, 76° 10′ 33.0″ E) of Hisar, India, along with the health survey of human subjects. The hydrochemistry of water collected from hand pumps, river canals, tube wells, submersibles, and the RO systems installed in various homes was explored for pH, EC, TH, TDS, turbidity, cations (Na+, Ca2+, Mg2+), anions (CO32−, HCO3−, Cl−, SO42−, NO3−, F−), and elements (Fe, Pb, Se) employing the ion chromatography, flame photometry, and ICP-AES techniques. Lead (Pb) and Selenium (Se) were detected in trace amounts (0.30–2.6 μg L−1; 0.10–4.1 μg L−1, respectively) in all the samples, including the samples collected from RO purifiers, but Iron (Fe) was not detected in RO samples even in trace amounts. The F-levels in hand pump water (HPW) and submersible water (SW) (1.9 and 1.7 mg L−1, respectively) and TDS levels in SW (3048 mg L−1) were found to be above WHO and BIS safe limits. TDS levels in the river canal (900 mg L−1), tube well (1104 mg L−1), hand pump (1170 mg L−1), and submersible samples (3048 mg L−1) were found significantly higher as compared to the RO personal water (ROPW; 216 mg L−1) and RO supply water (ROSW; 90 mg L−1). The collected epidemiological data reveals that 21%, 19%, 13%, and 12% of natives reported skin, kidney, hair fall, liver, and stomach issues, respectively, suspecting the crucial role of high TDS and fluoride levels in the area. This study also provides a comparison between the quality of RO and the direct supply water, along with correlation matrices for different parameters, which gives a rationale for the limitations of drinking direct supply water without any purification and RO water containing low mineral content. 相似文献
2.
三峡库区消落带农用坡地磷素径流流失特征 总被引:1,自引:0,他引:1
消落带是三峡库区重要的生态交错带,但自发农用和无序开发可能会造成更多的氮磷流失,进而加剧三峡库区水体富营养化。通过对库区连续3 a的定位监测(2011~2013年),研究了三峡库区消落带农用坡地的磷素流失特征。结果表明:次降雨事件中常规施肥处理的地表径流、壤中流总磷平均浓度分别为0.848±0.153、0.140±0.006 mg/L,其中地表径流中磷的形态以颗粒态为主,壤中流以溶解态的生物可利用磷为主。常规施肥下,地表径流、壤中流磷素年均流失通量分别为0.236±0.004、0.100±0.003 kg·hm 2,地表径流、壤中流磷素流失通量分别占总流失通量的70.2%、29.8%,地表径流是坡地磷素流失的主要途径,但壤中流也是不可忽视的重要途径。与常规施肥处理相比,减量施肥处理地表径流、壤中流磷素流失量分别降低了45.3%、40.0%。建议采取减量施肥的方式,以降低营养盐负荷,保护水环境。 相似文献
3.
Samson G. Mengistu Heather E. Golden Charles R. Lane Jay R. Christensen Michael L. Wine Ellen D’Amico Amy Prues Scott G. Leibowitz Jana E. Compton Marc H. Weber Ryan A. Hill 《Journal of the American Water Resources Association》2023,59(5):1162-1179
Eutrophication, harmful algal blooms, and human health impacts are critical environmental challenges resulting from excess nitrogen and phosphorus in surface waters. Yet we have limited information regarding how wetland characteristics mediate water quality across watershed scales. We developed a large, novel set of spatial variables characterizing hydrological flowpaths from wetlands to streams, that is, “wetland hydrological transport variables,” to explore how wetlands statistically explain the variability in total nitrogen (TN) and total phosphorus (TP) concentrations across the Upper Mississippi River Basin (UMRB) in the United States. We found that wetland flowpath variables improved landscape-to-aquatic nutrient multilinear regression models (from R2 = 0.89 to 0.91 for TN; R2 = 0.53 to 0.84 for TP) and provided insights into potential processes governing how wetlands influence watershed-scale TN and TP concentrations. Specifically, flowpath variables describing flow-attenuating environments, for example, subsurface transport compared to overland flowpaths, were related to lower TN and TP concentrations. Frequent hydrological connections from wetlands to streams were also linked to low TP concentrations, which likely suggests a nutrient source limitation in some areas of the UMRB. Consideration of wetland flowpaths could inform management and conservation activities designed to reduce nutrient export to downstream waters. 相似文献
4.
污染物总量控制制度是我国环境保护制度的重要组成部分。结合污染物总量控制制度的实施现状,分析实施过程中减排基数、核算体系、责任主体等方面存在的问题。提出,改革现行污染物总量控制制度,将总量控制与改革中的排污许可制相融合,落实企业主体责任,将总量指标与环境质量改善挂钩,建立差异化的减排核算体系,并加强日常监管,达到改善环境质量的目标。 相似文献
5.
With the environmental carrying capacity reaching its limits and the decreasing margin benefits of traditional production factors, the green transformation and green development through technological innovations has been a major direction for the future development of Chinese industries. However, the characteristics and heterogeneities of various types of industries call for different approaches regarding technological innovations. How to choose the most effective mode of technological innovation according to the characteristics of a certain industry has been a key issue. This paper measures the green total factor productivity of 32 industrial trades using the Slacks Based Measure(SBM)-DDF method. The effects of three innovation modes in the green transformation of industrial industry, including the independent innovation(Ⅱ), the technology introduction(TI), and the government support(GS), are empirically analyzed based on industry heterogeneity. Results indicate that the green total factor productivities of different industries show significant differences if taking into account the energy input and the undesirable output of pollutant emissions. The green total factor productivities of traditional high input,high pollution, and high energy consumption industrial trades were significantly lower than those with obvious green features. The year of 2009 is a leap year for the industrial green transformation in China. For resource-intensive industries, the II and the GS are the important ways to achieve green transformation. For labor-intensive industries, the TI is the best path to achieve green transformation, while for technology-intensive industries, the II is the primary driving force for the promotion of green developments. In addition, the innovation-compensating effect of the current Chinese environmental regulations to the resource-intensive industries has been revealed. Improving the overall scale and the industrial concentration of the industries is also beneficial for the green transformation of the industries. 相似文献
6.
7.
应用3S技术研究了太湖底质与水质总磷(TP)的分布情况,并结合水华频次分析了其相关性。结果表明:2016—2018年,太湖底质TP年均值在433~537 mg/kg波动,水质TP年均值从0.064 mg/L上升至0.087 mg/L。从空间分布来看,底质TP、水质TP和水华频次均呈现“西高东低”的规律,太湖西部区尤其是竺山湖区是需要开展治理的重点区域。3年间,太湖西部区水质TP上升,而底质TP与入湖河流TP下降,说明内源磷污染是太湖西部区水质TP升高的主要原因,须加强科学清淤。 相似文献
8.
9.
某执行《城镇污水处理厂污染物排放标准》(GB18918-2002)二级排放标准的污水处理厂升级改造要达到一级A标准,其难点之一为改造后总磷达标。为此进行了化学除磷深度处理的单元试验研究,为污水处理厂升级改造除磷工作提供理论依据和数据支持。 相似文献
10.
主要调查研究环渤海湿地芦苇对TC、TN、TP的吸收通量。调查表明,2008年环渤海湿地的芦苇面积为20.08×104hm2。2009年,芦苇总生物量在7月、10月和11月的调查结果分别为267.2×104t、183.4×104t和138.0×104t。7月、10月和11月,芦苇对TC的吸收通量分别为115.58×104t、80.68×104t、64.23×104t;对TN的吸收通量分别为4.03×104t、1.45×104t、0.84×104t;对TP的吸收通量分别为0.37×104t、0.10×104t、0.031×104t。 相似文献