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1.
由于底质(水底沉积物)污染可直接使环境恶化,并且污染的底质还能同水相互作用而产生水质的二次污染。因此,底质的污染已成为很大的问题,因而对底质问题的研究已呈现急剧增加的趋向。 日本环境厅于1972~1973年间主要对污染鱼具类的Hg和PCB的污染进行了环境  相似文献   

2.
本文根据1985~1989年佛山市主要纳污河流汾江河涌底质重金属的调查结果,分析了底质重金属含量的时空分布、重金属在底质中的累积及其相互关系。表明河涌底质重金属含量沿河分布的差异与工业排污位置有关;底质对重金属的单位累积量基本稳定,对不同重金属累积能力有明显差异;底质中亲铜元素(除Cd)相互关系较密切。提出三角洲河网区支涌底质评价标准和评价方法,并利用此方法评价了汾江河涌底质重金属污染状况,表明目前底质处于轻污染状态。  相似文献   

3.
舟山渔场近岸海域污染现状分析   总被引:1,自引:1,他引:1  
本文从舟山渔场近岸海域污染源及入海的污染物质分析入手,较详尽地叙述了舟山渔场近岸海域的水质、底质及生物体受污染的现状,并指出污染有加剧的趋势。提请注意处理好沿海的经济发展与保护舟山渔场渔业资源的关系。  相似文献   

4.
湘江是我国的重要水系之一,该流域的矿产资源丰富,气候温暖,雨量充沛,土地肥沃,是有名的“鱼米之乡”之一。但由于长期的生产和社会活动,使湘江某些江段受到不同程度的人为污染,对附近的人体健康和生态平衡可能有一定的影响。近年来,湘江流域的环境问题受到各方面的重视,对湘江的水体和底质的污染问题已有一些研究。本文主要对湘江中下游底质中Zn、  相似文献   

5.
前言 湘江流域是我国主要有色金属开采和冶炼的基地之一。该区矿产资源的开发利用带来了严重的重金属污染问题。其中株洲段霞湾港共有十七家工厂向港内排污,并流入湘江。有关该地区污染的研究工作已作了很多,但汞污染方面的工作却报导甚少。 已知可使用不同的方法研究河流底质中污染汞的化学行为:如用总量分布的方法确定污染源、用相关性分析研究污染物的分布  相似文献   

6.
松花江三岔河—哈尔滨江段汞污染分布状况的探讨   总被引:1,自引:0,他引:1  
通过对松花江三岔河—哈尔滨江段水体、底泥、水生生物中总汞和甲基汞污染的研究,基本查清了三岔河—哈尔滨江段水体、底泥、水生生物中总汞和甲基汞含量范围;掌握了此江段汞的污染分布状况;“一松”江水对来自“二松”汞的净化情况;水生生物的汞污染水平与底质和江水汞含量之间的相关性、江水和水生生物含汞量的季节变化;甲基汞与总汞之间的变化关系。为松花江汞污染的防治途径,汞污染分布状况深入研究提供了必要的基础资料。  相似文献   

7.
运河(杭州段)底质有机质与重金属元素相关性的探讨   总被引:7,自引:0,他引:7  
通过对京杭大运河 (杭州段 )底质的监测 ,探讨了底质有机质与 8种重金属元素的相关性 ,并对其成因作出了解释 ,得出了 8种重金属在运河 (杭州段 )底质中易积累的顺序。  相似文献   

8.
氯代有机物是一类在生产和生活中广泛应用并被大量排放到环境中的难降解有机污染物质,一旦进入生态环境,就会在水体、土壤和底质中长期残留,并在食物链中不断积累、富集,从而对生物体产生危害。因此,对受这类难降解有机物污染的环境修复是目前所迫切需要解决的环境问题之一。基于物理和化学修复方法成本较高易造成二次污染,文中探讨了国内外生物修复技术的研究进展,并对难降解氯代有机物污染环境修复的研究方向进行了展望,由于环境中的污染物质复杂多变,联合生物修复技术将成为未来的研究热点。  相似文献   

9.
实验以扎龙湿地底泥做为介质,模拟表面流湿地系统,研究了不同底质和进水浓度对表面流湿地净化效率及其稳定性的影响。通过对各个指标去除率均值,变异系数和方差的综合分析,表明在本实验设计的高、中、低3种浓度梯度下,高、中浓度进水时,湿地底质的净化效果更好。粘土对TN、NO3--N去除效果最好,粉砂土对NH4+-N、COD去除效果较好。3种底质对磷的去除效果没有显著差异。此外,随着进水浓度的不同,底质因素的影响也发生相应的变化。即粘土和粉砂土的去除率受进水浓度影响大,亚砂土的去除效果相对稳定。实验结果客观反映了扎龙湿地不同底质地段的净化污水功能,为表面流人工湿地净化不同浓度的污水水质和选择最佳净化效果的湿地底质提供理论依据。  相似文献   

10.
生物膜法的动力学过程包括底质和氧的液膜扩散、生物膜内扩散与生物膜内生化反应等几个组成部分。目前,不少数学模式是直接采用米氏公式或一次关系式建立反应速度和进水底质浓度之间的关系。但是,由于膜扩散的影响,膜内底质环境与膜表面的液相环境是不同的,尤其当生物膜厚度较大、底质的  相似文献   

11.
Nematode communities from river water and sediments were assessed for the abundance, feeding types, maturity indices and nematode channel ratio (NCR). The sampling sites studied included different levels of pollution and contamination from agricultural, industrial and sewage sources. The nematode abundance found in the sediment samples was more than that in the water samples. The lowest nematode abundance in sediment samples and the lowest NCR in water samples were both found at the industrial pollution site. Water samples showed positive correlation between the NCR and river pollution index (RPI). Mean maturity indices in sediment samples were inversely correlated with RPI. The pollutant source determined the relationship between NCR and pollution level, while maturity index always showed negative correlation with pollutant level regardless of the pollutant sources. The nematode abundance and its community structure were both reliable bioindicators for monitoring long-term river pollution in both qualitative and quantitative aspects.  相似文献   

12.
Rush Lake (WI, USA), the largest prairie-pothole lake east of the Mississippi River, has been contaminated with lead pollution as a result of over 140 years of waterfowl hunting. We examined: (1) the extent of lead pollution in Rush Lake sediments and (2) whether lead pollution in Rush Lake is affecting the abundance and community structure of indigenous sediment bacteria. Sediment lead concentrations did not exceed 59 mg Pb kg(-1) dry sediment. No relationship was observed between sediment lead concentration and the abundance of aerobic (P=0.498) or anaerobic (P=0.416) heterotrophic bacteria. Similarly, lead did not appear to affect bacterial community structure when considering both culturable and nonculturable community members. In contrast, the culturable fraction of sediment bacteria in samples containing 59 mg Pb kg(-1) exhibited a unique community structure. While factors other than lead content likely play roles in determining bacterial community structure in the sediments of Rush Lake, these data suggest that the culturable fraction of sediment bacterial communities is affected by elevated lead levels.  相似文献   

13.
The aims of this paper were to survey the total Hg levels and distribution character in intertidal sediment in continental coast of Shanghai, and identify the environment factors that might influence the sediment Hg concentrations, and to assess the pollution degree and potential ecological risk of Hg in sediment. Eighty-eight surface sediment samples and 18 sediment cores were collected for Hg contamination analysis. Physicochemical properties including Eh, particle size, content of total organic carbon (TOC), and acid volatile sulfide (AVS) were also measured. Index of geo-accumulation (I geo) and potential ecological risk index were used respectively to assess the pollution levels and the ecological risk of sediment Hg. The average of total Hg concentrations in surface sediments was 107.4?±?90.9 ng/g with the range from 0 to 465.9 ng/g. Higher Hg concentrations were generally found in surface sediments near sewage outfalls and the mouth of rivers. Total Hg concentrations were significantly correlated with TOC (p?<?0.05) both in surface (r?=?0.24) and core (r?=?0.29) sediments, but not with the other environment factors (Eh, AVS, and particle size). Geo-accumulation index indicated that Hg contamination in intertidal sediments was generally at none to moderate degree, while potential ecological risk index demonstrated that the risk caused by Hg were at moderate to considerable level. Intertidal sediment in continental coast of Shanghai has generally been contaminated by Hg, and it might pose moderate to considerable risk to the local ecosystem. The Hg contamination is related more to the coastal pollution sources and complicated hydrodynamic and sedimentary conditions than the other environment factors studied.  相似文献   

14.
Artificial-lawn mats were used as sediment traps in floodplains to measure sediment input and composition during flood events. To estimate the natural variability, 10 traps were installed during two flood waves at three different morphological units in a meander loop of the River Elbe. The geochemical composition of deposited and suspended matter was compared. The sediment input showed weak correlations with concentration and composition of river water. It also correlated poorly with flood duration and level as well as distance of trap position from the main river. This is due to the high variability of the inundation, different morphological conditions and the variability of sources. The composition of the deposits and the suspended matter in the river water was comparable. Hence, for the investigated river reach, the expected pollution of the floodplain sediments can be derived from the pollution of the suspended matter in the river during the flood wave.  相似文献   

15.
This paper's survey of the pollution of the Wujin'gang River is important because it is one of the main rivers flowing into Meiliang Bay of Lake Taihu in eastern China. Trace metals (TMs) in this paper are described according to their pollution index (P i). Cluster analysis and correlation analysis are utilized for group sites and to assess co-contamination. Toxicity effect analysis was conducted using individual sediment quality guideline quotients (SQGQs) and mean SQGQs. The results showed that sediment from the Wujin'gang River basin was affected by nutrients, heavy metals, and polycyclic aromatic hydrocarbons (PAHs), which are an essential contamination source for both Meiliang Bay and Zhushan Bay of Lake Taihu. The discharge of TMs has significant correlations to total nitrogen (TN) and total phosphorus (TP); however, no significant correlations were observed between the content of PAHs and TMs. Toxicity effect results show that sediment in the Wujin'gang River basin threatens sediment-dwelling organisms. The harmful effect was mainly caused by heavy metals especially Cd, Cr, Ni, and Cu. Sediment dredging is an effective way to control pollution from internal rivers especially for the pollution of TN and heavy metals in the Wujin'gang River basin.  相似文献   

16.
底泥营养盐的释磷对富营养化湖泊的影响   总被引:8,自引:0,他引:8  
富营养化是中国湖泊的重大环境问题。当湖泊的污染外源受到控制以后,由于沉积物(底泥)中营养盐内负荷的存在和释放,湖泊仍然可以发生富营养化。底泥营养盐就成为湖泊富营养化的主导因子,特别是溶解态的磷会逐步释放,成为水体富营养化的主导因子。沉积物中磷的循环在一定程度上决定着富营养化的进程,对水体磷含量有深刻的影响。结合国内外研究动态,对底泥磷形态、磷释放与水体水质的关系作了概述,并对底泥磷释放的研究方向以及控制湖泊富营养化发表了一些见解。  相似文献   

17.
Huang KM  Lin S 《Chemosphere》2003,53(9):1113-1121
A great deal of effort was enforced to reduce the pollution of the Keelung River in the past 20 years. A set of sediments covering most of the Keelung River drainage basin was analyzed for bulk sediment heavy metal concentrations, grain size content and Pb-210 dating in order to understand the spatial variations of sediment heavy metal contents as well as to evaluate the effectiveness of pollution control. The results showed that anthropogenic pollution and grain size are two of the most important factors in controlling spatial variations of metals in the Keelung River sediments. In addition, little reduction of sediment heavy metal concentrations was observed in the Keelung River drainage basin. Large spatial variations of metals and grain size were observed. High concentrations of zinc, copper, lead and cadmium were found in sediments near the main outlets of the adjacent Da-Wu-Lun Industrial Park and municipal waste drainage systems. Anthropogenic sources of heavy metal have altered the natural sediment heavy metal distributions. Positive linear relationships between aluminum, iron and fine-grained sediments showed that spatial grain size variations controlled the natural aluminum and iron concentrations in sediments. Zinc, copper, lead and cadmium contents were much higher than those measured 15 years ago. The unusually high concentrations of heavy metals, high enrichment factors and their rapid increases with time in Pb-210 dated core showed that the efforts in heavy metal reduction were futile. A proper regulation to prevent further heavy metals from entering into the river is urgently needed.  相似文献   

18.
西湖沉积物中元素分布特征研究   总被引:2,自引:0,他引:2  
分析测定了西湖沉积物(20m钻探样品)不同层次中Fe、Al、Ca、Mg、Ti、Mn、Cu、Zn、Cd、Ni、Hg、Cr、As、Co、V等15种元素的含量,并根据元素的分布特征探讨了西湖沉积物的形成发展及重金属污染状况。  相似文献   

19.
An approximately 59-year (1955–2014) sedimentary record of metal elements (Cu, Pb, Zn, Ni, Co, Mn, and Fe) in a sediment core, collected from the Huaihe River, Huainan City, Anhui Province, China, was reconstructed by using 210Pb geochronology. Copper, Zn, Ni, Co, and Mn evaluated by enrichment factor (EF) indicated minor contamination due to water pollution accidents of the Huaihe River that occurred in 1990s and 2004. Lead presented the most severe pollution among the metals studied, especially during 1957–1974. The use of leaded petrol and atmospheric deposition of coal combustion flue gases could have contributed to Pb contamination. In spite of the general good quality (mean sediment pollution index (SPI) 35.69) of the sediment core evaluated by SPI based on the principal component analysis, worse sediment qualities in the upper section (<6 cm, 2004) were still observed, suggesting intensive human activities causing the increasing concentrations of metals in recent decades.  相似文献   

20.
Laboratory experiments were carried out to study the influence of temperature (24, 28 and 30 °C) and pH (1–10) on organic mercury (CH3HgCl) transfer and accumulation in an experimental ecotoxicological model. We followed the evolution of CH3HgCl in a basic model (water+air) by varying temperature and pH. In a second step, we completed the model by adding sediment and fish. We added CH3HgCl to water at the beginning of each experiment which was repeated at least three times. Results demonstrated that mercury was released from methylmercury into the air regardless of water pH and its concentration in the air increased with increasing pH. By contrast, in presence of sediment, almost all the mercury was fixed onto the sediment and no mercury was traced in air or in water. Interestingly, in the presence of sediment, the life span of fish under methylmercury exposure lasted longer despite their higher mercury body level content at their death. These results indicate that water is a bad exposure indicator for aquatic pollution. In case of chronic pollution, sediments, fish and aquatic plants are more appropriate indicators.  相似文献   

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