Geographical information system-based groundwater quality index assessment of northern part of Kolkata,India for drinking purpose     

Suranjana Banerji  Deblina Mitra 《国际地球制图》2019,34(9):943-958

Groundwater is a resource under stress. In both developed and developing countries, it has been found that increasing human influence has led to the contamination of the groundwater resource. To understand the magnitude of this problem, a study was conducted in 58 wards within Northern part of Kolkata, India, where water samples from tube wells were collected and analysed on essential drinking water quality parameters, prescribed by WHO. Using Principal component analysis, and Water quality index mapping, the aforementioned results have been interpreted. This has helped to depict that not only is the groundwater unsuitable for drinking, but that the parametric values have a tendency to increase abruptly within the shortest of ranges, indicating urban pollution as the root cause of contamination. This paper shall thus discuss the spatial change in groundwater quality in northern Kolkata and suggest measures which might be implemented to secure a sustainable future for the city.  相似文献   

山东铝业公司第二赤泥堆场地下水环境影响评价          下载免费PDF全文

刘国爱  郝建军 《山东国土资源》2000,(3)

山东铝业公司拟建第二赤泥堆场于母猪山石灰石采空区。该堆场运行后将对下游地下水体造成污染 ,pH值将达到 1 1 .3。为此 ,拟采用赤泥、石灰配比为 1∶9的抗渗垫层进行防渗。根据水流运移特征及防渗材料特征 ,评价满足堆场使用 2 0年的最佳垫层厚度为 1 .0m。  相似文献   

A comparative study of mercury contamination in the Tagus estuary (Portugal) and major French estuaries (Gironde,Loire, Rhône)     

G. Figueres  J.M. Martin  M. Meybeck  P. Seyler 《Estuarine, Coastal and Shelf Science》1985,20(2):183-203

Concentrations of mercury were determined for the waters, suspended matter and sediments of the Tagus and of major French estuaries.The Tagus estuary is one of the most contaminated by mercury derived from the outfalls of a chloralkali plant and from other industrial sources. In deposited sediments the median level, 1·0 μg Hg g^?1, is twenty times higher than the natural background and Hg contents depend on the sediment grain-size, age and the distance from waste-outfalls. Suspended matter is more regularly and highly contaminated (median value: 4·5 μg Hg g^?1). In the French estuaries Hg levels in the suspended material decrease with salinity due to dilution and/or remobilization processes. In June 1982, in the Loire estuary, high values of Hg are observed in the middle estuary and attributed to urban and industrial sources.In the Tagus estuary, the general distribution of total dissolved Hg confirms the contamination: it increases seaward from 10 ng 1^?1 in the river to 80 ng 1^?1 in the estuary outlet. The dissolved Hg is almost totally organic in the river, inorganic in the middle estuary due to inorganic Hg effluents and again organic in the lower estuary. This variation is related to the dissolved organic carbon values. The dissolved Hg levels in the Loire Estuary (5–300 ng 1^?1) are much higher than in the Gironde estuary (3–6 ng 1^?1) and of the same order as those observed in the Tagus estuary.  相似文献   

镉在包气带中的迁移与积累特征     

张光辉 《地球科学与环境学报》1995,(2)

本文论述了镉在包气带中迁移积累问题，提出了镉在包气带中的迁移和积累模式并用实验结果与之加以验证，指出了镉在各类土壤中的存在形式及在不同地球化学环境镉的危害性是有所不同的。  相似文献   

贵州土壤环境污染现状及其防治建议   总被引：3，自引：0，他引：3  

张建江  杨胜元  王林 《贵州地质》2008,25(4)

通过贵州省土壤环境污染情况的分析,表明我省土壤环境污染状况严重。规范人类生产生活行为,控制和消除土壤污染源,改善生态环境,保护国家和人民生命财产安全,加强土地资源的保护工作势在必行。  相似文献   

Land-based sources of pollution along the Izmit Bay and their effect on the coastal waters     

Enis Morkoç  Oya S. Okay  Ayşe Edinçliler 《Environmental Geology》2008,56(1):131-138

The degree and the contribution of each point source to the pollution were determined in the Izmit Bay during the period 1999–2000. During 8 campaigns, samples from 11 points in the channels and water samples from 5 points in the coastal sea were collected for chemical analysis. The important pollutant parameters taken into account are inflow of total organic carbon (TOC), total suspended solids (TSS), total phosphorus (TP), total nitrogen (TN), nitrate, ortho-phosphate, ammonia and total polycyclic aromatic hydrocarbons (t-PAHs) in the discharge channels, and TOC, TSS, nitrate, ortho-phosphate, chlorophyll-a, temperature, dissolved oxygen (DO), and salinity in the coastal stations of the Bay. It should be pointed out that the industrial wastewaters entering the bay are partially treated but domestic wastes are discharged directly into the surface waters without any treatment. Of the pollution parameters measured in the channels, the highest concentrations, except TP, were observed in the Dil River and in the Eastern Channel. Concentrations of TOC, TSS, TN, TP, ammonia, nitrate and o-phosphate were found at concentrations of 231, 290, 152, 3.8, 16, 79, and 3.07 mg/L, respectively. Annual inflows of TOC were 21,301, 580, and 775 t/year and for TSS were 26,742, 585, and 1505 t/year in the western, central and eastern parts, respectively. The results show that the water quality of the bay has been deteriorated and 80% of the pollution was caused by Dil River for all parameters measured.  相似文献   

Testing spatial heterogeneity in geographically weighted principal components analysis     

Javier Roca-Pardiñas  Tomás R. Cotos-Yáñez  Rubén Pérez-Álvarez 《International journal of geographical information science》2017,31(4):676-693

We propose a method to evaluate the existence of spatial variability in the covariance structure in a geographically weighted principal components analysis (GWPCA). The method, that is extensive to locally weighted principal components analysis, is based on performing a statistical hypothesis test using the eigenvectors of the PCA scores covariance matrix. The application of the method to simulated data shows that it has a greater statistical power than the current statistical test that uses the eigenvalues of the raw data covariance matrix. Finally, the method was applied to a real problem whose objective is to find spatial distribution patterns in a set of soil pollutants. The results show the utility of GWPCA versus PCA.  相似文献   

The role of fluvial geomorphic processes in the dispersal of heavy metals from mine sites     

Jerry R. Miller 《Journal of Geochemical Exploration》1997,58(2-3)

It is not uncommon for more than 90% of the total metal load in rivers to be transported in the solid phase, either sorbed onto particle surfaces and coatings, or incorporated into mineral grains. Fluvial geomorphic processes are therefore of fundamental importance in the transport and fate of heavy metals derived from mine sites. In this paper, the role of physical processes in the dispersal of heavy metals in river systems are reviewed for channels that have (1) remained relatively unchanged in terms of process and form following the introduction of mine wastes, and (2) exhibited a significant metamorphosis in channel form in response to the influx of mining and milling debris. In general, all processes responsible for the variations in metal concentrations within sediments moving through stable channels also operate in channels undergoing metamorphosis. However, downstream, lateral, and vertical patterns in metal values tend to be more complex where channel transformations have occurred. This complexity results, in part, because temporal and spatial changes in the types, rates, and magnitudes of erosional and depositional processes lead to highly variable stratigraphic sequences of post-mining age, and because greater quantities of contaminated debris is stored along the channel margins where it can be eroded and sporadically redistributed during times of flood.  相似文献   

松树沟超镁铁岩和铬铁岩的微量元素及锶氧同位素地球化学研究     

张泽军 《矿物岩石》1992,(4)

根据岩石学特征,本文全岩样品被分为三组。各组岩石具有不同的微量元素含量和锶氧同位素组成,还呈现不同的变异特征。各类岩石的Rb,Ba,Nb,Sr等元素含量明显高于原始地幔值。这些特征与其他已发表的资料均反映出超镁铁岩和铬铁岩有地幔残余成因和岩浆结晶成因,以及上涌地幔经历过多期部分熔融和大陆岩石圈中壳幔物质混染作用。  相似文献   

Arsenic contamination in surface drainage and groundwater in part of the southeast Asian tin belt,Nakhon Si Thammarat Province,southern Thailand   总被引：2，自引：0，他引：2  

M. Williams  F. Fordyce  A. Paijitprapapon  P. Charoenchaisri 《Environmental Geology》1996,27(1):16-33

The occurrence of human health problems resulting from arsenic contamination of domestic water supplies in Ron Phibun District, Nakhon Si Thammarat Province, southern Thailand was first recognized in 1987. The area has an extensive history of bedrock and alluvial mining, the waste from which is typically rich in arsenopyrite and related alteration products. In 1994 a collaborative study was instigated involving Thai and British government authorities to establish the distribution and geochemical form of As in surface drainage and aquifer systems in the affected area, the probable sources of As contamination, and the potential for problem alleviation. Hydrochemical analyses of surface- and groundwaters have confirmed the presence of dissolved As at concentrations exceeding WHO potable water guidelines by up to a factor of 500. Contamination of the shallow alluvial aquifer system is systematically more severe than the underlying carbonate-hosted aquifer. Deep boreholes may therefore provide the best available potable water source for the local population. The presence of up to 39% of total As as arsenite (H₃AsO₃) within the carbonate aquifer may, however, constitute a hidden toxicological risk, not evident in the shallow groundwater (in which arsenate species account for > 95% of total As). Mineralogical investigations of As-rich tailings and flotation wastes were undertaken to evaluate their likely impact on water quality. The results indicate that although some flotation wastes contain up to 30% As, the rate of leaching is extremely low. Consequently the As loading of drainage emanating from such waste is below the subregional average. Analyses of the silty alluvium that covers much of the central sector of the study area have highlighted As concentrations of up to 5000 mg kg^–1, probably carried by disseminated arsenopyrite. Following sulfide dissolution, the mobility of As in this material may be high (with resultant contamination of shallow groundwater) due to the low Fe content of the soil. On the basis of the data acquired, a range of pollution mitigation schemes are currently under investigation including Fe supplementation of alluvium and microbial degradation of disseminated arsenopyrite.  相似文献