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1.
通过调查黑河流域地下水中的硝酸盐、亚硝酸盐、氨氮等离子含量,分析了黑河流域地下水中硝酸盐、亚硝酸盐、氨氮等含量的空间分布特征,并依据地下水供水适宜性划分表,通过叠加计算,对黑河流域地下水"三氮"进行质量区划。结果表明:黑河流域地下水硝酸盐污染呈现出线状和面状污染的趋势,亚硝酸盐氮和氨氮呈点污染特性,污染不具有区域性和连续性。黑河流域可以直接饮用(Ⅰ—Ⅲ类水)的地下水资源占91.1%、经适当处理可以饮用(Ⅳ类水)的地下水资源占7.19%、不能直接饮用的地下水资源(Ⅴ类水)占1.71%。 相似文献
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《地下水》2017,(5)
利用2012-2017年蚌埠市城市地质调查地下水水样测试结果,采用单项组分评价法和综合评价法进行地下水质量评价,采用单要素污染指数和迭加型指数法进行污染评价。地下水质量综合评价结果显示,蚌埠市河漫滩区浅层孔隙水Ⅳ、Ⅴ类水所占比重较大。地下水污染评价结果显示,未受污染的占11.54%,轻度污染的占23.08%,中度污染的占15.38%,重度污染的占50.00%。蚌埠市河漫滩区浅层地下水污染形势总体较为严峻,应加强区域地下水保护,编制专项水污染防治规划,加强地下水监测,建立并完善地下水动态监测网络,提升地下水污染防治能力,遏制地下水污染恶化,改善水环境质量,有效保护蚌埠市河漫滩区地下水资源的质量。 相似文献
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通过测试地下水样品中“三氮”含量,采用非致癌风险评价模型进行健康风险评价.结果表明,与《地下水质量标准》（GB14848—2017）限值对比,硝酸盐氮超标率8%,主要分布在研究区东南部及西南部区域;氨氮超标率10%,主要分布在中部及南部区域.地下水中Ⅰ、Ⅱ、Ⅲ类水质占比83%;Ⅳ及Ⅴ类水水质占比17%.地下水样品中“三氮”总非致癌风险指数及总致癌性风险指数均低于美国环境保护署推荐的健康风险评价标准.整体上研究区“三氮”污染程度相对较轻,“三氮”污染区域主要分布于人类活动密集地区.健康风险评价可为地区地下水中“三氮”污染监控和治理提供技术参考. 相似文献
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《地下水》2021,(4)
以河南新乡市凤泉区重金属污染典型区为研究对象,采用单因子污染评价方法,基于3项无机毒理指标、5项毒性(类)重金属指标(中深层无砷指标)和26项有机指标,对浅层和深层地下水污染进行综合评价,结果显示:研究区内浅层地下水污染现象较为明显,受一定的硝酸盐氮、毒性(类)重金属污染,其中浅层地下水未污染(Ⅰ级)和轻污染(Ⅱ级)样品占总样品的12. 7%,中污染(Ⅲ级)样品数占总样品数的21. 8%,重污染(Ⅳ、Ⅴ、Ⅵ级)样品数占总样品数的65. 5%,且主要为极重污染(Ⅵ类);中深层地下水未污染(Ⅰ级)和轻污染(Ⅱ级)样品占总样品的70%,中污染(Ⅲ级)样品数占总样品数的10%,重污染(Ⅴ)样品数只占总样品数的20%,无极重污染水样,深层地下水整体为未污染和轻污染。在后期应加强区域地下水监测网络建设,探索污染组分的迁移转化规律,尽快开展地下水污染场地的修复治理工作。 相似文献
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针对地下水质量评价中综合评价法的不足,应用信息熵计算评价指标的权重,并充分利用有序分隔概念,建立了基于熵权的属性识别模型。选择TDS、COD、总Fe、总Mn、Cl-、SO42-、NO2-、F-作为评价指标,运用基于熵权的属性识别法对开封南郊垃圾场浅层地下水进行地下水质量评价。评价结果表明,基于熵权的属性识别法所得的评价结果水质明显优于综合评价法所得的结果;研究区内各样本的评价指标中,SO42-和NO2-的权重最大,Cl-、COD、总Fe和F-的权重次之,TDS和总Mn的权重最小;Ⅰ类、Ⅱ类、Ⅲ类、Ⅳ类和Ⅴ类水在研究区内的分布面积所占比例分别为1.7%、2.5%、26.7%、12.2%和56.9%;浅层地下水质的空间分布在研究区域内具有一定的规律,以靠近垃圾场的L01井和G54井为中心水质最差,为Ⅴ类水,以此为中心向外扩展,水质逐渐好转,依次分布Ⅳ类水和Ⅲ类水。Ⅲ类水的分布向研究区的东部和北部偏移,而在研究区的南部多分布Ⅰ类和Ⅱ类水,水质优良。 相似文献
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对合肥地区浅层地下水取样分析,采用单因子评价法、分类指标评价法和综合评价法对浅层地下水质量进行评价。结果显示:可以直接饮用的地下水资源(Ⅰ类水、Ⅱ类水和Ⅲ类水)占59.3%,经过适当处理可以饮用的地下水资源(Ⅳ类水)占30.5%,不能直接饮用的地下水资源(Ⅴ类水)占10.2%。在地下水评价指标中,挥发性有机指标较好,毒性重金属指标和半挥发性有机指标次之,无机毒理指标和一般化学指标较差。影响地下水质量的化学组分主要为铁、锰、总硬度、溶解性总固体、氟、硫酸盐和钠+钾等无机组分,与人类活动相关的化学组分主要为氨氮、硝酸盐、亚硝酸盐、六价铬、砷、铝、碘、氯化物等无机组分和苯并(a)芘等有机组分。影响地下水质量的原因主要为城市和乡镇工业污水、生活污水排放,农村农药、化肥使用及生活垃圾污染。 相似文献
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Hand-pump wells in the Tarkwa gold mining district and the geologically similar Bui area were chemically analysed and compared in an effort to determine whether groundwaters in the Tarkwa area have been affected by mining. Significant chemical differences attributed to mine water discharges have been observed in streams in the Tarkwa area. Groundwater chemistry from hand-pump wells in Tarkwa and Bui areas reveal similar hydrochemical facies, predominantly Ca–Na–Mg–HCO3–Cl. However, except for SO42–, ionic concentrations of groundwaters from Bui are greater than those from Tarkwa probably due to differences in (1) water availability during sedimentation (2) water-rock interactions and/or residence times for water. No demonstrable impact of mining on groundwaters from hand-pumped wells in the Tarkwa area has been noted. Hydrogeological inference suggests that the main streams which receive mine water discharges are both gaining and are groundwater divides. The overwhelming majority of population centres and mining operations are located on opposite sides of these groundwater divides, therefore, it is unlikely aquifers tapped for drinking by these communities would be affected by mining. 相似文献
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The correlation between sulfate concentrations in Finnish headwater streams and atmospheric sulfate deposition has been studied by using data from the streamwater chemistry in August–September 1990 and computed S deposition from the anthropogenic emissions. The sulfate concentrations and acidity in water are interpolated and smoothed into a deposition model grid. These data are compared with geological and pedogeochemical (glacial till) background information. The areas where the streamwater SO4 concentrations are mainly controlled by either anthropogenic S deposition or sulfur in till is estimated by applying the fuzzy Gustafsson-Kessel algorithm, which provides a soft clustering suitable for overlapping control factors. Residual areas can be well explained by the SO4-rich Littorina clay deposits. The higher overall background SO4 concentrations in streams in south Finland compared with central and northern Finland are an indisputable consequence of the heavier S deposition load in the south. However, anthropogenic sulfur deposition has a clear correlation with the sulfates in streamwaters only in northeastern Lapland impacted by the large industrial emissions in the Kola Peninsula. The secondary sulfide and sulfate minerals of marine Littorina sediments are dominating sources in the broad coastal belts, as are the primary sulfide minerals locally in the Pori-Vammala area, at the eastern end of the main sulfide ore belt between Lake Ladoga and the Gulf of Bothnia, in the Outokumpu area, and in the Peräpohja and central Lapland schist belts. Consequently, in addition to the anthropogenic deposition, there are natural sources of sulfur which cause acidity of streamwaters. 相似文献
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本文从水文地质条件和环境水文地质条件入手,讨论了位于欧亚大陆腹地的渭干河——塔里木河流域这样一个大区域的地下水水化学分带问题。进而通过对渭干河、库车河冲积扇的砂体分布规律以及地下水的补给、径流、排泄特征差异的研究,阐明了地下水水化学分带性的形成机制。 相似文献
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Enis Morkoc Legovic Tarzan Oya Okay Huseyin Tufekci Vildan Tufekci Leyla Tolun Fatma Karakoc 《Environmental Geology》2007,53(1):103-112
The Izmit Bay is an elongated semi-enclosed bay in the Marmara Sea. It is being increasingly polluted by both domestic and
industrial waste discharge since 1970’s. A monitoring program was conducted between 1999-2000 to document the state of pollution
in the bay. This includes the effect of Marmara (Izmit) earthquake (magnitude 7.4) that occurred in August 1999. A stable
two-layer ecosystem exists in the bay throughout the year due to continuous inflows of the saltier Mediterranean and brackish
Black Sea waters to the Marmara basin. Therefore, the principal biochemical characteristics of the bay are governed by the
two-layer flow system over the basin. Dissolved oxygen (DO) is generally at a saturated levels in the surface layer which
is 10 to 15 m thick, but it is depleted to 60–70 μM in the lower layer, exhibiting a steep gradient in the sharp halocline.
When the earthquake occurred, great loads of industrial wastes were released into the bay surface waters, which enhanced primary
production in the upper layer and thus large export of particulate organic matter to lower layer and eventually to the bottom.
Accordingly, DO was consumed and anoxic condition was established even in the upper layer/halocline interface, the halocline
and bottom waters of the eastern and central bay. In this period, concurrent increases were observed in phosphate and ammonia
contents at the halocline and in deep waters whilst the nitrate was almost consumed via denitrification processes in the anoxic
water. Recently, the industrial C, N and P loads increased by as much as 8 fold within five years (1995–2000) whilst domestic
inputs increased by 50%. Total organic matter discharged to the bay increased more than double within the last 15 years. Besides,
most factories in the region release toxic wastes into the bay after only partial treatment. 相似文献
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A new approach is proposed to simulate the daily variation of chlorophyll a in one-dimensional streams. This approach uses the plant primary production rate to quantify the phytoplankton growth rate. The delta method, which is a piecewise analytical solution technique, is applied to determine the diurnal variation in plant primary production rate. The approach is tested by applying it to the Gumsuck stream in the Kyonggi-Do province in Korea. The optimization technique with constraints is used to obtain the best running results. Application of this approach shows that the values calculated using the method presented here are in good agreement with the measured values. Therefore, we conclude that this technique realistically simulates the daily variation of chlorophyll a. 相似文献
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Conceptual model of the evolution of groundwater quality at the wet zone in Sri Lanka 总被引：2，自引：1，他引：1
The evolution of groundwater quality at a wet zone in Sri Lanka was made clear using field investigation, chemical and isotopic
analyses methods. In the wet zone, the concentrations of major ions and electrical conductivity (EC) in the groundwater are
low with small seasonal change. Except for sodium, silica and chloride, the EC and other major ion concentrations increase
along the groundwater flow direction. The contributions of bicarbonate and calcium ions to the increase in EC are the largest
among the major ions. The groundwater quality shows calcium-bicarbonate type, the initial stage of the Chebotarev series.
There is a seasonal change in isotopic composition. The isotopically lighter groundwater was found at the valley bottom in
the rainy season. Under the very heavy precipitation conditions, the slope of the regression line between δD and δ18O and deuterium excess for groundwater are close to 8 and 10, respectively. In other cases, the slopes of the regression lines
and deuterium excess are, less than 8 and 10, respectively.
Received: 5 August 1998 · Accepted: 19 October 1998 相似文献
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A variety of water supply sources are used in the rural Guatemalan Highlands. Formal municipal systems are rare, but villagers
frequently form local water committees that construct spring-based supply systems. Recent work has indicated that groundwater
may be a viable water supply source. The water quality from these two sources was characterized as well as water from other
common sources including surface water and precipitation collection systems. Typically, all of the water sources contained
unacceptable levels of coliform bacteria except for groundwater from a drilled well. Water monitoring indicated that not only
did the water contain coliforms at the actual sources, but the infrastructure used to transmit the water to points of use
may also be a source of coliforms. A cost comparison indicates that groundwater may be a cost-competitive, higher quality
alternative to traditional spring-fed water systems. 相似文献
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M. Fontana F. Grassa G. Cusimano R. Favara S. Hauser C. Scaletta 《Environmental Geology》2009,57(4):885-898
In the Rocca Busambra area (mid-west Sicily, Italy), from November 1999 to July 2002, 23 water points including wells and
springs were sampled and studied for their chemical and isotopic compositions. Two rain gauges were also installed at different
altitudes, and rainwater was collected monthly to determine the isotopic composition. The obtained results revealed the Rocca
Busambra carbonate complex as being the main recharge area on account of its high permeability value. From a chemical view
point, two main groups of water can be distinguished: calcium–magnesium–bicarbonate-type and calcium–magnesium–chloride–sulphate-type
waters. The first group reflects the dissolution of the carbonate rocks; the second group probably originates from circulation
within flyschoid sediments. Three water wells differ from the other samples due to their relatively high Na and K content,
which probably is to be referred to a marked interaction with the “Calcareniti di Corleone” formation, which is rich in glauconite
[(K, Na)(Fe3+, Al, Mg)2(Si, Al)4O10(OH)2]. In accordance with WHO guidelines for drinking water (2004), almost all the samples collected can be considered drinkable,
with the exception of four of them, whose NO3
−, F− and Na+ contents exceed the limits. On the contrary, the sampled groundwater studied is basically suitable for irrigation. 相似文献
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Since landfill operations ceased in the early 1980s at the Woodlawn landfill Superfund site in northeastern Maryland, USA,
the carcinogen vinyl chloride monomer (VCM) has persisted in the site ground water at concentrations in places greater than
100 ppb. Investigations of VCM concentrations from monitoring well data from 1981 through 1991, which were published in 2001,
concluded that concentrations were cyclic and were not dissipating. Data from 1991 to 2000 confirm VCM persistence, showing
concentration peaks as late as 1997 in the eastern part of the site. These values are significantly above both drinking water
standards (>MCL of 2 ppb) and lifetime excess cancer risk (E-6 risk level) from exposure since birth (>0.024 ppb). Sources
for VCM are landfill wastes (PVC-sludge) and effluent from an on-site transfer station. In addition to direct release of VCM
from wastes, other chlorinated hydrocarbons, trichloroethene and perchloroethene (TCE and PCE) are also present in the ground
water, and these compounds can degrade into VCM. Persistence of VCM concentrations is the result of leachate generation, mostly
from multi-source wastes in the vadose zone, with subsequent infiltration into the regional aquifer. Increases in VCM concentrations
(new leachate generation) alternated with decreases in VCM concentrations (infiltration without leachate) in a cyclic fashion,
during this 20-year period. 相似文献
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Hydrogeological and hydrochemical framework of regional aquifer system in Kali-Ganga sub-basin, India 总被引：5，自引：0，他引：5
The central Ganga Basin is one of the major groundwater reservoirs in India. The Kali-Ganga sub-basin is a micro watershed
of the central Ganga Basin, containing a number of productive aquifers. A detailed hydrogeological investigation was carried
out, which reveals the occurrence of a single-tier aquifer system down to 163 m bgl (metres below ground level), but at places
it is interleaved with clay layers; thus imparting it a two-to three-tier aquifer system. These aquifers are unconfined to
confined in disposition. The transmissivity, storage coefficient and hydraulic conductivity are determined as 2178 m2/day, 1.12×10–5 and 120 m/day, respectively. The groundwater of the basin is fresh, of an alkali-bicarbonate type and is suitable for irrigation
and domestic use. However, in certain areas, extensive agricultural activities, and domestic and industrial effluents have
caused some deterioration of groundwater quality. This study contains data of where the concentration of Fe, Pb, Cd, Cr and
Ni are higher than the permissible limits, which may be hazardous to public health.
Received: 2 March 2000 · Accepted: 3 July 2000 相似文献