Heavy Metal Load Of Soil, Water And Vegetables In Peri-Urban Delhi

Peri-urban lands are often used for production of vegetables for better market accessibility and higher prices. But most of these lands are contaminated with heavy metals through industrial effluents, sewage and sludge, and vehicular emission. Vegetables grown in such lands, therefore, are likely to be contaminated with heavy metals and unsafe for consumption. Samples of vegetables i.e., spinach (Spinacia oleracea L.) and okra (Abelmoschus esculentus L.); soil and irrigation water were collected from 5 peri-urban sites of New Delhi to monitor their heavy metal loads. While heavy metal load of the soils were below the maximum allowable limit prescribed by the World Health Organization (WHO), it was higher in irrigation water and vegetable samples. The spinach and okra samples showed Zn, Pb and Cd levels higher than the WHO limits. The levels of Cu, however, were at their safe limits. Metal contamination was higher in spinach than in okra. Spatial variability of metal contamination was also observed in the study. Bio-availability of metals present in soil showed a positive relationship with their total content and organic matter content of soil but no relationship was observed with soil pH. Washing of vegetables with clean water was a very effective and easy way of decontaminating the metal pollution as it reduced the contamination by 75 to 100%.     

Irrigation Efficiency and Quality of Irrigation Return Flows in the Ebro River Basin: An Overview

The review analysis of twenty two irrigation efficiency (IE) studies carried out in the Ebro River Basin shows that IE is low (average IE)_avg(= 53%) in surface-irrigated areas with high-permeable and shallow soils inadequate for this irrigation system, high (IE)_avg(= 79%) in surface-irrigated areas with appropriate soils for this system, and very high (IE)_avg(= 94%) in modern, automated and well managed sprinkler-irrigated areas. The unitary salt (total dissolved solids) and nitrate loads exported in the irrigation return flows (IRF) of seven districts vary, depending on soil salinity and on irrigation and N fertilization management, between 3–16 Mg salt/ha⋅ year and 23–195 kg NO)₃ ⁻-N/ha⋅ year, respectively. The lower nitrate loads exported from high IE districts show that a proper irrigation design and management is a key factor to reduce off-site nitrogen pollution. Although high IE’s also reduce off-site salt pollution, the presence of salts in the soil or subsoil may induce relatively high salt loads (≥14 Mg/ha⋅ year) even in high IE districts. Two important constrains identified in our revision were the short duration of most surveys and the lack of standards for conducting irrigation efficiency and mass balance studies at the irrigation district level. These limitations {emphasize the need for the establishment of a permanent and standardized network of drainage monitoring stations for the appropriate off-site pollution diagnosis and control of irrigated agriculture.     

Geo-spatial analysis of land–water resource degradation in two economically contrasting agricultural regions adjoining national capital territory (Delhi)

The present study was aimed at characterizing the soil-water resource degradation in the rural areas of Gurgaon and Mewat districts, the two economically contrasting areas in policy zones-II and III of the National Capital Region (NCR), and assessing the impact of the study area's local conditions on the type and extent of resource degradation. This involved generation of detailed spatial information on the land use, cropping pattern, farming practices, soils and surface/ground waters of Gurgaon and Mewat districts through actual resource surveys, standard laboratory methods and GIS/remote sensing techniques. The study showed that in contrast to just 2.54% (in rabi season) to 4.87% (in kharif season) of agricultural lands in Gurgaon district, about 11.77% (in rabi season) to 24.23% (in kharif season) of agricultural lands in Mewat district were irrigated with saline to marginally saline canal water. Further, about 10.69% of agricultural lands in the Gurgaon district and 42.15% of agricultural lands in the Mewat district were drain water irrigated. A large part of this surface water irrigated area, particularly in Nuh (48.7%), Nagina (33.5%), and Punhana (24.1%) blocks of Mewat district, was either waterlogged (7.4% area with 0.05 ppm). In fact, sub-surface drinking waters of some areas around battery and automobile manufacturing units in Gurgaon and Pataudi blocks were associated with exceptionally high (>0.1 ppm) Ni concentrations. In general, the ground waters of waterlogged or potentially waterlogged areas in the rural areas of Mewat were more contaminated than the ground waters in the rural areas of Gurgaon district with deeper (>5 m) water depths.Though Cr concentrations in the surface and sub-surface irrigation waters of both Gurgaon and Mewat districts were far above the maximum permissible limit of 1 ppm, their bio-available soil-Cr concentrations were well within permissible limit. Even bio-available Ni concentrations in agricultural lands of Gurgaon district associated with Ni contaminated sub-surface irrigations were well within desirable limit of 0.20 ppm. This was primarily attributed to the calcareous nature of the soils of the study area. About 35% of Gurgaon district and 59% of Mewat district irrigated with poor quality waters were salt-affected. These waterlogged/potentially waterlogged calcareous-salt affected soils of Mewat district were having acute zinc (Zn) deficiency (<0.6 ppm). Some areas with extremely high iron (Fe: 20-25 ppm) and Mn (10-25 ppm) concentrations were also noticed in the Gurgaon, Nuh and Punhana blocks. Generation of reduced conditions owing to paddy cultivation in areas with 3-3.5 m water depths appeared to be the main cause of such point contaminations. Extensive cadmium (Cd) contamination was also noticed in the waterlogged sodic agricultural lands of Nagina village in Mewat district associated with a large scale scrap automobile and battery business. The study could document the processes and provide spatially accurate information to the managers (e.g., National Capital Region Planning Board) and the concerned citizen groups. It could, in fact, clearly point out that dumping of industrial and domestic wastewaters especially from NCT-Delhi into river Yamuna and, to some extent, from NCT-Delhi re-located hazardous industrial units into Najafgarh drain tributaries at Delhi-Gurgaon boundary, and poor "off-farm" water management practices were the main reasons for extensive (point/non-point source) land-water degradation in Gurgaon and Mewat districts of NCR.     

基于分形求和模型的克拉玛依市空气质量评价

以克拉玛依市4个区2012年的大气自动监测数据为样本,基于分形求和模型,分析大气污染物的分布特征,利用分维数确定污染物浓度分布的随机程度,计算 SO2、NO2、PM10的大气环境背景值与标准值,确定适合于评价区域的ORAQI指数计算公式,并与 API指数作对比。ORAQI指数计算结果显示,克拉玛依市全年环境空气质量基本呈现“U”字形变化,春夏季大气质量好于秋冬季,全年空气质量有明显的季节变化,4个区中克拉玛依区空气质量相对较差,乌尔禾区空气质量最好。相对于 API指数的均匀分布结果,ORAQI指数具有更好的次要污染物体现能力,可以综合体现所评价的各项污染因子的贡献。     

Evaluation of groundwater quality and its suitability for drinking and agricultural use in Thanjavur city, Tamil Nadu, India

As groundwater is a vital source of water for domestic and agricultural activities in Thanjavur city due to lack of surface water resources, groundwater quality and its suitability for drinking and agricultural usage were evaluated. In this study, 102 groundwater samples were collected from dug wells and bore wells during March 2008 and analyzed for pH, electrical conductivity, temperature, major ions, and nitrate. Results suggest that, in 90% of groundwater samples, sodium and chloride are predominant cation and anion, respectively, and NaCl and CaMgCl are major water types in the study area. The groundwater quality in the study site is impaired by surface contamination sources, mineral dissolution, ion exchange, and evaporation. Nitrate, chloride, and sulfate concentrations strongly express the impact of surface contamination sources such as agricultural and domestic activities, on groundwater quality, and 13% of samples have elevated nitrate content (>45 mg/l as NO₃). PHREEQC code and Gibbs plots were employed to evaluate the contribution of mineral dissolution and suggest that mineral dissolution, especially carbonate minerals, regulates water chemistry. Groundwater suitability for drinking usage was evaluated by the World Health Organization and Indian standards and suggests that 34% of samples are not suitable for drinking. Integrated groundwater suitability map for drinking purposes was created using drinking water standards based on a concept that if the groundwater sample exceeds any one of the standards, it is not suitable for drinking. This map illustrates that wells in zones 1, 2, 3, and 4 are not fit for drinking purpose. Likewise, irrigational suitability of groundwater in the study region was evaluated, and results suggest that 20% samples are not fit for irrigation. Groundwater suitability map for irrigation was also produced based on salinity and sodium hazards and denotes that wells mostly situated in zones 2 and 3 are not suitable for irrigation. Both integrated suitability maps for drinking and irrigation usage provide overall scenario about the groundwater quality in the study area. Finally, the study concluded that groundwater quality is impaired by man-made activities, and proper management plan is necessary to protect valuable groundwater resources in Thanjavur city.     

Secondary desertification due to salinization of intensively irrigated lands: The Israeli experience

Secondary salinization of intensively irrigated lands is an increasingly alarming redesertification process experienced in many irrigated regions of the developed countries. The major cause is a profound interference in the geochemical/salt balances of irrigated regions. A case-in-point is the recent salinization of the Yizre'el Valley, a 20,000 ha intensively irrigated region in Israel. The extremely intensive and advanced agroecosystem developed in the region since the 1940s included pumping and importing irrigation water by the National Water Carrier, large-scale reclamation and reuse of municipal sewage water, winter flood impoundment in reservoirs for summer irrigation, and cloud seeding to enhance rainfall. Modern irrigation methods were applied, including sprinkler, trickle, moving-line, and center-pivot systems. Water use efficiency at any level was very high. Nevertheless, large-scale salinization of regional water resources and many fields had developed in the mid-1980s. Reconstructing and evaluating the water and salt balances of the Yizre'el Valley (using Cl as the representative salt constituent) shows that as water use in the valley increased to about 60 million m³ per year, the importing of soluble salts by water totaled 15,000 tons of Cl per year. Recirculated salt — salt picked up by impounded surface water and applied to fields — increased significantly and in the late 1980s amounted to more than 9,000 tons Cl per year. The source of recirculated salts was the accumulated salts in soils and in the shallow aquifer in the valley, which were leached by floodwater or drained or infiltrated into reservoirs, grossly and adversely affecting water quality. Analysis of the Yizre'el Valley's case points to the utmost importance of maintaining the geochemical balances in addition to increasing irrigation efficiency. An irrigated region may achieve geochemical balance by the following means: limiting the extent of irrigated areas, developing a well-maintained drainage system that drains tail-water and salinized shallow-aquifer water, and devoting a significant portion of water for regional leaching. The sustained long-term productivity of irrigated lands in arid zones crucially depends on correctly managing water and soil resources. Regional management of irrigated lands to prevent secondary desertification will be aimed at carefully balancing the undisputed benefits of irrigation with the long-term (on time scales of 10 to 100 years) detrimental processes set in motion when irrigation is introduced to arid and semiarid zone soils.     

A multi-lysimeter investigation on the mobility and persistence of pesticides in the loam soil of the Fucino Plain (Italy)

In order to evaluate the impact of intensive horticulture on the water resources of the Fucino Plain, one of the most important agricultural settlements of Central Italy, the mobility and persistence in the soil of five commonly used pesticides was investigated by means of multi-lysimeter experiments. The fate of simazine, carbaryl, dicloran, linuron and procymidone was evaluated in the laboratory under experimental conditions simulating as closely as possible both pesticide application and irrigation practices required by the local crops. An efficient extraction procedure followed by chromatographic analysis, allowing the simultaneous determination of the applied chemicals, was used to monitor the pesticide residues in the soil columns as a function of time from application and depth. The experiment, carried out for about 60 days, revealed that soil contamination apparently involves only the surface layer since none of the investigated pesticides was detected at depths greater than 20-30 cm. However, the five pollutants exhibit a quite different behaviour that can be related to their physico-chemical properties.     

TOXIC TRACE ELEMENT POLLUTION IN GROUND WATERS AROUND PATANCHERU AND BOLARAM INDUSTRIAL AREAS, ANDHRA PRADESH, INDIA: A GRAPHICAL APPROACH

Patancheru and Bolaram are satellite industrial towns nearHyderabad with over 300 large andmedium scale pharmaceutical, heavy engineering, paints, paperand chemical factories. The industriesof the area generate a cumulative 8 × 10⁶ l/day ofeffluents which are being directly dischargedon to surrounding land, irrigation fields, and surface waterbodies which finally enter into theNakkavagu River a tributary of the Manzira River. The presentstudy on abundance and distributionpattern of toxic trace elements indicates the quantitativeaspect of pollution in the Nakkavagu Basin.Migration patterns drawn for TDS, toxic elements such as Cu,As, Se, Zn, B, Cr and iron indicate thatpollutants discharged by the industries are entering thesurface and groundwater system (aquifers) andare also migrating towards the Manzira River furtherdeteriorating the entire hydrological setup of the area.Entry and dispersion of pollutants in the hydrological systemis shown by distribution diagrams. Aconservative estimate indicates that the effect of pollutantson the agricultural lands and water bodiesextends 0.25 to 0.5 km to either side of the Nakkavagu Riverover a length of 25 km. In addition tothis, the movement of pollutants with ground water in thedownstream direction worsened thehydrological system and increased the possibility ofgeo-accumulation of pollutants in biota. Openwells, dug wells and tanks have become useless and redundantas the concentrations of Cu, Se, As,B, Cr and Fe have increased to 5 to 10 times the permissiblelimits. Several villages have beenaffected by the toxic pollutants in the area. The groundwatersystem is polluted over a large area asshown in elemental migration diagrams and is not potable.Tentatively an area of 20 sq km can becategorized as the worst affected by various pollutants.     

Use of multivariate indicator kriging methods for assessing groundwater contamination extents for irrigation

Multivariate geostatistical approaches have been applied extensively in characterizing risks and uncertainty of pollutant concentrations exceeding anthropogenic regulatory limits. Spatially delineating an extent of contamination potential is considerably critical for regional groundwater resources protection and utilization. This study used multivariate indicator kriging (MVIK) to determine spatial patterns of contamination extents in groundwater for irrigation and made a predicted comparison between two types of MVIK, including MVIK of multiplying indicator variables (MVIK-M) and of averaging indicator variables (MVIK-A). A cross-validation procedure was adopted to examine the performance of predicted errors, and various probability thresholds used to calculate ratios of declared pollution area to total area were explored for the two MVIK methods. The assessed results reveal that the northern and central aquifers have excellent groundwater quality for irrigation use. Results obtained through a cross-validation procedure indicate that MVIK-M is more robust than MVIK-A. Furthermore, a low ratio of declared pollution area to total area in MVIK-A may result in an unrealistic and unreliable probability used to determine extents of pollutants. Therefore, this study suggests using MVIK-M to probabilistically determine extents of pollutants in groundwater.     

Environmental impact from agrochemicals in Bali (Indonesia)

Irrigation of paddy has been practised for centuries in Bali, based on the use of upland weirs for diverting river waters to irrigate downstreams lands ranging from upland terraces to flat coastal plains. While in earlier times, traditional irrigation practices have met the island's food needs, in recent decades an increasing population has increased food requirements to levels surpassing the productivity of traditional methods. Government assistance programs were initiated beginning in about 1960, and a major new program, called the Bali Irrigation Project, is now being implemented. These programs recognize that little additional farm lands will be available, hence their objective is to increase productivity through intensified agriculture, including the use of high-yield rice varieties and increasing amounts of agricultural chemicals, including both fertilizers and pesticides. The feasibility study for the Bali Irrigation Project included an evaluation of the pollutional effects of agricultural chemicals used in Bali. The study showed that past use of hard organochlorides has pervasively polluted the island's soil and water resources and, while the Government's programs now use only relatively degradable chemicals, considerable environmental damage has already occurred and much care will be needed in avoiding the use of hard toxics in the future. The study also indicated no adverse effects from increased use of fertilizers.     

Modeling of Cr contamination in the agricultural lands of three villages near the leather industry in Kasur,Pakistan, using statistical and GIS techniques

Kasur is one of the hubs of leather industry in the Punjab, Pakistan, where chrome tanning method of leather processing is extensively being used. Chromium (Cr) accumulation levels in the irrigation water, soil, and seasonal vegetables were studied in three villages located in the vicinity of wastewater treatment plant and solid waste dumping site operated by the Kasur Tanneries Waste Management Agency (KTWMA). The data was interpreted using analysis of variance (ANOVA), clustering analysis (CA), and principal component analysis (PCA). Interpolated surface maps for Cr were generated using the actual data obtained for the 30 sampling sites in each of the three villages for irrigation water, soil, and seasonal vegetables. The level of contamination in the three villages was directly proportional to their distance from KTWMA wastewater treatment plant and the direction of water runoff. The highest level of Cr contamination in soil (mg kg^?1) was observed at Faqeeria Wala (37.67), intermediate at Dollay Wala (30.33), and the least in Maan (25.16). A gradational variation in Cr accumulation was observed in the three villages from contaminated wastewater having the least contamination level (2.02–4.40 mg L^?1), to soil (25.16–37.67 mg kg^?1), and ultimately in the seasonal vegetable crops (156.67–248.33 mg kg^?1) cultivated in the region, having the highest level of Cr contamination above the permissible limit. The model used not only predicted the current situation of Cr contamination in the three villages but also indicated the trend of magnification of Cr contamination from irrigation water to soil and to the base of the food chain. Among the multiple causes of Cr contamination of vegetables, soil irrigation with contaminated groundwater was observed to be the dominant one.     

Assessment of irrigation water quality. A proposal of a quality profile

Water quality indices provide a simple and understandable tool for managers on the quality and possible uses for irrigation water, however an individual quality factor alone is not enough to evaluate the irrigation water quality because it could be restrictive and sometime it could give an unfavorable qualification. The aim of this paper was propose a quality profile of irrigation water using the preexisting water quality indices to be applied to arid and semi-arid regions. As a case studied, the water of the Del Molle River (Nogolí, San Luis, Argentina) was researched. Samples were collected during the period October 2005-May 2006. Conductivity, pH, total hardness, sulphate, nitrate, nitrite, alkalinity, chloride, sodium, potassium, TDS, DO and phosphate were analyzed. The irrigation water quality, according to Riverside Norm, belongs to C(2)-S(1) class, according to Wilcox Norm as excellent to good, according to Scott quality factor it is good and according to SAR < 10 and according to RCS it is recommendable. From the obtained data, it can be concluded that the water quality profile was good, so it is useful for normal irrigation agriculture.     

Evaluation of electrochemical processes for the removal of several target aromatic hydrocarbons from petroleum contaminated water

Ground and surface water contamination resulting from the leakage of crude oil and refined petroleum products is a serious and growing environmental problem throughout the world. Consequently, a study of the use of electrochemical treatment in the clean-up was undertaken with the aim of reducing the water contamination by aromatic pollutants to more acceptable levels. In the experiments described, water contamination by refined petroleum products was simulated under laboratory conditions. Electrochemical treatment, using aluminium electrodes, has been optimised by full factorial design and surface response analysis in term of BTEX and PAHs removal and energy consumption. The optimal conditions of pH, current density, electrolysis time, electrolyte type, and electrolyte concentration have then been applied in the treatment of real water samples which were monitored as petroleum contaminated samples. Treatment results have shown that electrochemical methods could achieve the concentration of these pollutants to undetectable levels in particular groundwater and surface water, hence, they can be highly effective in the remediation of water contaminated by aromatic hydrocarbons, and the use of these processes is therefore recommended.     

Environmental contaminants in nonviable eggs of the endangered Mississippi sandhill crane (Grus canadensis pulla)

Our objectives were to determine if concentrations of environmental pollutants and microbial contamination in nonviable eggs of the endangered Mississippi sandhill crane (Grus canadensis pulla) contributed to egg failure. Six eggs collected in 1990 and four in 1991 contained only background levels of organochlorine pesticides and polychlorinated biphenyls (PCBs), and tests for microbial contamination were all negative. Two eggs contained late dead embryos, but neither revealed obvious abnormalities. Three eggs contained potentially harmful concentrations (23, 39, 146 pg/g, wet mass) of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs), based on 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TCDD-EQ) for combined compounds. Because of the scarcity of material suitable for laboratory examination and the endangered status of the crane, we recommend that nonviable eggs continue to be monitored for toxic pollutants.     

Evaluation of Pb (II) biosorption utilizing sugarcane bagasse colonized by <Emphasis Type="Italic">Basidiomycetes</Emphasis>

The contamination of water resources by metallic ions is a serious risk to public health and the environment. Therefore, a great emphasis has been given to alternative biosorption methods that are based on the retention of aqueous-solution pollutants; in the last decades, several agricultural residues have been explored as low-cost adsorbent. In this study, the ability of Pb (II) biosorption using sugarcane bagasse modified by different fungal species was evaluated. The presence of carbonyl, hydroxyl, and carboxyl groups in the biosorbent was observed by spectroscopy in the infrared region. By scanning electron microscopy, changes in the morphology of modified material surfaces were observed. The highest adsorption capacity occurred at pH 5.0, while the shorter adsorbate-adsorbent equilibrium was at 20 min, and the system followed the pseudo-second-order model. The maximum biosorption in isotherms was found at 58.34 mg g^?1 for modified residue by Pleurotus ostreatus U2-11, and the system followed the Langmuir isotherm. The biosorption process was energetically spontaneous with low desorption values. This modification showed great potential for filters to remove Pb (II) and provide the preservation of water resources and animal health.     

黄河口的水质、底质污染及其变化

分析了2001年在黄河口附近所取的3处水样和3处泥样中污染物的含量,并与历史数据进行了比较.利用<地表水环境质量标准>(GB3838-2002)和美国国家海洋大气管理局(NOAA)水体泥沙质量标准等分别对水体和底泥中的重金属(砷)和氮磷污染进行了评价.认为黄河口的水污染严重,主要污染物为汞和氮;泥沙污染尚不严重,但污染物的增长率高;水体中较高的氮含量和泥沙中氮含量的迅速增高可能会对渤海湾的富营养化情况产生影响.     

Water quality associated public health risk in Bo, Sierra Leone

Human health depends on reliable access to safe drinking water, but in many developing countries only a limited number of wells and boreholes are available. Many of these water resources are contaminated with biological or chemical pollutants. The goal of this study was to examine water access and quality in urban Bo, Sierra Leone. A health census and community mapping project in one neighborhood in Bo identified the 36 water sources used by the community. A water sample was taken from each water source and tested for a variety of microbiological and physicochemical substances. Only 38.9% of the water sources met World Health Organization (WHO) microbial safety requirements based on fecal coliform levels. Physiochemical analysis indicated that the majority (91.7%) of the water sources met the requirements set by the WHO. In combination, 25% of these water resources met safe drinking water criteria. No variables associated with wells were statistically significant predictors of contamination. This study indicated that fecal contamination is the greatest health risk associated with drinking water. There is a need to raise hygiene awareness and implement inexpensive methods to reduce fecal contamination and improve drinking water safety in Bo, Sierra Leone.     

新疆某县河流水质现状评价及其变化趋势分析

利用新疆某县境内主要河流的水质监测资料,依据水质评价标准《地表水环境质量标准》(GB 3838-2002),评价了某县境内主要河流的环境质量,采用季节性肯达尔法进行趋势分析检验。结果表明,新疆某县境内河流水质总体优良,水质级别为Ⅰ、Ⅱ类,可以作为饮用水源地、农田灌溉用水、一般工业用水的水源。从趋势分析检验结果看,水质基本稳定,没有受到明显的人为污染。     

Irrigation water quality and the benefits of implementing good agricultural practices during tomato (Lycopersicum esculentum) production

The implementation of good agricultural practices (GAP) from irrigation water to the tomato packaging process enhances the safety of fresh produce and its value throughout the food chain. The aim of the present study was to show that fresh produce farms that apply and enforce GAP could reduce the presence of Salmonella in finished produce. Samples were collected biweekly from six packing houses from the central region of Sinaloa, México, for the isolation of Salmonella spp by the ISO 6579:2002 method, and the isolated strains were serotyped and genotyped by the Kauffmman-White scheme and pulsed field gel electrophoresis (PFGE), respectively. Salmonella strains were detected in 13 (36.1 %) irrigation water samples, while only two tomato samples were positive (5.5 %). Eight different serotypes were identified in irrigation water, and Salmonella Oranienburg (34 %) was the most prevalent; however, only Salmonella Agona and Salmonella Weltevreden were present on tomatoes. Salmonella Oranienburg was the most widely dispersed and variable serotype, with 10 different PFGE profiles. Salmonella Weltevreden was isolated from both types of samples, albeit with distinct genetic profiles, implying that the sources of contamination differ. These results confirm the utility of implementing good agricultural practices to reduce Salmonella contamination in irrigation water and the packaging process.     

流域重点工业污染源识别特征成分谱建立技术

研究了基于生产排放全过程、多相、多类污染物并举的污染源识别特征成分谱建立技术。首先建立污染源排放完整图谱,包括原辅料、中间物质、产品、各工艺废水污染物、水处理设施进口和出口污染物等。然后从排放完整图谱中解析出特征污染物。对于废水中的常规污染物和金属污染物,采用与受纳水体浓度相比较的方式得到污染源识别特征污染物,建议将浓度超过受纳水体1倍的污染物定为特征污染物。对于有机污染物,将质量分数之和大于90%的污染物集定为特征有机污染物,并按照有机物类别进行分类。最后开发建立动态的水污染源排放数据库。应用该技术建立了石化行业典型企业的排放特征成分谱,发现这些特征组分具有很好的代表性,为水污染源的识别提供了基础数据。