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1.
The dissolved and particulate trace metals in large and middle-sized Chinese rivers remain comparable with other less-disturbed world systems. Levels of nutrients in Chinese rivers are high due to erosion over the drainage area and the application of chemical fertilizers, which induces an N/P ratio up to 100–1,000. The concentrations of organic pollutants in Chinese rivers are ranked at the lower end of those of world systems; however, pollution has been identified in coastal waters from north to south of the country. In estuarine and coastal waters, dissolved trace metals illustrate a feature of remobilization, while non-conservative distribution is observed, with exceptions for iron and aluminum. Particulate trace metals demonstrate a fairly stable distribution along the salinity gradient, when the absolute concentration is normalized to reference materials. In high-turbidity estuaries, seaward nutrient flux can be increased by a factor of 5–10. Finally, the N/P ratio approaches 10–20 at the interior of the East China Sea, indicating that in coastal regions photosynthesis changes from P to N and Si limitations. Electronic Publication  相似文献   

2.
湖北省主要大中型水库富营养状况及特征分析   总被引:1,自引:0,他引:1  
水库在城市供水、工业用水、水产养殖、农业灌溉、水利防汛以及景观旅游等方面发挥着重要的作用,但随着社会经济的发展,部分水库的富营养化状况日益严重,成为影响社会经济发展的重大环境问题。通过在2010年的3、6、7、10月对湖北省30座主要大中型水库进行布点采样,对水体的水质状况分别进行了调查、监测,采用《地表水环境质量标准》湖库标准进行水质类别分析,采用湖库营养状态指数法对湖泊富营养化评价, 并运用因子聚类分析方法对这些水库进行了类型划分。结果表明:30座大、中型水库有14座水库水质类别为Ⅱ类~Ⅲ类, 占467%; 有8座水库水质类别为IV类,占267%;有8座水库水质类别为Ⅴ类或劣Ⅴ类,占267%;除白云湖水库为轻富营养化外,其余29座水库均属中营养状态;氨氮、磷作为营养物质是这些水库富营养化的主要影响因素,溶解氧对水体富营养化有重要影响,总氮、水温和有机物污染对水体富营养化产生较大影响;30座水库聚类分为城市工业废水污染源型、生活污水污染源型、农业非点源污染源型和养殖轻污染型4种水库类型。针对水库的污染类型,分别提出了减缓防治措施  相似文献   

3.
鄱阳湖蝶形湖泊水体氮磷等的变化及污染初步评价   总被引:2,自引:0,他引:2  
分别于2014年夏季7月和冬季12月对鄱阳湖蝶形水域的9个湖泊进行了采样,并对湖泊水质基础性指标TN、TP、NH_3-N、NO_3~--N、NO_2~--N、溶解性磷酸盐、TOC、COD_(Mn)和叶绿素a进行了测定与分析。据此同时运用单因素评价法、均值型指数综合评价法和营养状态指数法对鄱阳湖蝶形水域的地表水水环境的污染现状和污染程度进行了评价,以更全面和准确地反映鄱阳湖蝶形水域的水质状况。结果显示:(1)鄱阳湖蝶形水域水质总体符合GB3838-2002III类水标准;(2)7月水质总体优于12月水质。12月总氮含量和总磷含量基本都高于7月,叶绿素a含量除中湖池12月值略低于7月外,其它点位12月值均高于7月。7月总氮值为0.6~1.3 mg/L,总磷值为0.02~0.15 mg/L,叶绿素a为2.2~6.7 mg/L;12月总氮值为0.6~2.0 mg/L,总磷值为0.04~0.19 mg/L,叶绿素a为3.8~34.7 mg/L;(3)7月和12月水质营养状态介于中营养和轻度富营养,水体主要污染物质为总氮和总磷。7月蚌湖营养状态为轻度富营养,其它点位为中营养,12月除常湖、梅溪湖和大汊湖营养状态为中营养,其它点位均为轻度富营养;(4)位于南部的象湖、常湖、白沙湖和大汊湖水质整体较其它蝶形湖泊差,主要是受到工业废水、生活污水和农业面源污染的赣江和饶河的污染输入影响所致。基于以上调查测试结果提出保护和改善鄱阳湖水环境的可行性措施,以促进鄱阳湖蝶形水域水资源的开发利用,实现经济与环境及资源的协调可持续发展。  相似文献   

4.
武汉东湖富营养化现状分析及治理对策   总被引:29,自引:3,他引:26  
随着人口的增长和经济的快速发展,东湖的水环境污染日益严重,尤其以富营养化的危害最大。采用营养状态指数法,对武汉东湖十个湖区进行了富营养化评价,得出富营养化的水体占到整个面积的62.21%,中营养的水体占到37.79%。磷是东湖富营养化的主控因素,在明确水体中磷富集的主要原因是点源污染的前提下,分析了东湖现有治理措施和存在的问题,建议东湖富营养化的治理要因湖区而宜,在彻底控制点源污染的同时,结合生态建设,用人工湿地的方法控制面源污染,并对富营养化严重的湖区,采取底泥疏浚工程削减内源营养盐。在东湖富营养化治理的同时,必须加强对东湖的管理,健全环境立法,强化环境监督,将东湖污染的控制纳入法制化轨道。  相似文献   

5.
Exchange of trace gases between the oceans and the atmosphere affects the atmospheric content and cycling of a range of chemical species which are related to climate change, ozone layer depletion, acid deposition, eutrophication, atmospheric particle formation, photo-oxidants, trace metals and persistent organic pollutants (POPs). The effects and impacts of air–sea exchange of these gases can be local, regional and global. Until now, most of the research has concentrated on the sea–air exchange of trace gases in the open ocean. The flux rates of the trace gases from the coastal waters to the air are much higher than the rates for the open ocean and the contribution of the coastal areas to the total oceanic emissions of these trace gases can be significant on a global scale. This contribution can be as high as 50% and more for nitrous oxide and COS. Concerning the contribution of the trace gas production in the coastal areas to the total global production of these gases, it can be concluded that this contribution seems to be below 2% except for nitrous oxide. However, it should be pointed out that on the local and even regional scale the emissions in the coastal areas can be very important, contributing substantially to the total emission of these gases in a studied area. Thus, there is a need to carry out studies in the future with the aim to provide more accurate understanding of the production and sea–air exchange processes for these gases around the world. Electronic Publication  相似文献   

6.
The consequences of anthropogenic impact on the water area of Amur Bay (the Sea of Japan) near Vladivostok include the eutrophication of coastal waters and littering with various objects used as artificial substrates, which protect sedentary animals from predators and contribute to the survival of their larvae. An indicator of eutrophication, the diatom Skeletonema costatum accounting for 81–96% of the total abundance of phytoplankton (Stonik and Selina, 1995), is consumed mainly by barnacles and the Pacific oyster. Thus, these animals gain an advantage in the colonization of artificial substrates. The results of the study suggest that eutrophication will lead to changes in the structure of the marine community.  相似文献   

7.
利用多元统计方法研究了湖北梁子湖水体及底泥中12种微量元素和重金属(As,Ba,Co,Cr,Cu,Hg,Mn,Ni,Pb,Sb,Sr和Zn)的含量及空间格局,并通过饮用水及地表水质量标准及地质累积指数评价梁子湖水质及底泥状况。结果表明:梁子湖的水体质量较好,仅Cu是潜在污染物质;对湖泊底质而言,As是主要污染物质,Cu、Pb和Zn处在轻微的污染状态。空间格局显示:受人类活动的影响,湖泊水体中的重金属分布有较强的区域性,最大值出现在人类活动相对集中的梁子岛附近;在湖泊底泥中由于地质背景一致性而差别不大。相关分析表明,较之湖泊水体,湖泊底泥中的重金属元素的关系更密切,强相关性说明它们可能有共同的来源。未来研究应结合湖泊中大型水生植物及鱼类的重金属含量更全面考虑生态学效应,为恢复湖泊生态环境的管理提供重要参考。  相似文献   

8.
太湖流域农田生态系统管理与非点源污染控制   总被引:3,自引:0,他引:3  
太湖是我国的五大淡水湖之一,正面临着严重的水体富营养化问题。随着点源污染得到逐步治理,农田非点源污染已成为太湖水体富营养化的主要污染源。概述了太湖流域农田生态系统管理与非点源污染控制,指出随着流域内化肥用量以及农田氮磷盈余量的不断增加,流域内农田非点源污染负荷将进一步加大。农田中的氮磷通常通过农田排水和地表径流等途径进入地表水体。为有效控制农田非点源污染,应实施科学合理的农田生态系统管理:避免氮磷肥的过量使用,适当增施有机肥和钾肥,推广应用测土配方施肥,加强微生物肥和控效肥等新型肥料的研制和推广,实行保护性耕作,合理安排农事活动时间,以此减少非点源污染物形成;调整土地利用方式,优化土地资源配置,对潜在的非点源污染物进行有效的截留。  相似文献   

9.
如何对湖泊生态环境修复效果进行评价是当前湖泊生态修复工作的难点所在,以武汉市内不同修复状态湖泊为研究对象,通过分析湖泊水体营养盐浓度、水质类别、综合营养状态指数TLI(Σ)与湖泊不同有机质δ15N的关系,探讨以水体中某一有机质δ15N指示城市湖泊水污染状态,进而作为湖泊修复效果评价指标的可行性。结果表明:武汉南湖、东湖、内沙湖水质分别为劣Ⅴ类、Ⅳ类、Ⅲ类;水体富营养化程度分别为重度富营养、轻度富营养、中营养;南湖有机质δ15N均值最高为13.193‰(8.394‰~19.380‰);东湖δ15N次之为8.191‰(5.162‰~13.488‰);内沙湖δ15N最低为2.940‰(0.001‰~6.433‰)。不同湖泊有机质δ15N与表层水 c(TN)、c(DIN)、c(NH+4-N)、c(TP)、水质类别和TLI(Σ)呈正相关趋势,其中悬浮有机质、沉水植物δ15N与水污染参数的相关性最为显著,均能有效表征城市湖泊水污染状态;为了采样的简便性及样品的通用性,建议以悬浮有机质δ15N作为城市湖泊水污染状态及水环境治理效果的快速评价指标。  相似文献   

10.
Under the globalization, the coastal China becomes a hot area of the international manufacturing investment due to its priority location, excellent environment, lower labor and land costs, etc. However, the fast industrialization has aroused the great demolishment to the local ecological environment. For example, the heavy water eutrophication in Taihu Lake has affected the source of drinking water for the cities around the lake. Anyway, in order to keep the economic increase and reduce the resource ex- pense and pollution at the same time, it is necessary to encourage the greening of industrial enterprises actively for sustainable de- velopment. On the basis of the investigation of industrial enter- prises in Wuxi city within Taihu Basin, the relatively developed region in coastal China, this paper analyzed the development process of green industry. This article concluded that governmen- tal principal is the main pressure for enterprises to protect envi- ronment while the market factor plays a part role. Moreover, en- terprises in the high technology development zone work better in environmental protection than those in the villages and towns, while the large enterprises work better than those small enterprises.  相似文献   

11.
太湖水质参数中小尺度空间结构特征   总被引:7,自引:1,他引:6  
经济的发展和人们生活水平的提高,造成了太湖的富营养化和生态环境的严重破坏。太湖的水质污染目前已严重影响了整个流域的可持续发展,并对人们的身体健康造成潜在的危害。治理太湖、保护太湖已成为人们刻不容缓的任务。了解湖泊水质参数空间结构特征是进行太湖环境评价的重要前提,也是合理治理太湖的重要基础。地统计学的出现为精确描述湖泊水质参数空间结构提供了有效的工具。应用地统计学技术对太湖3种水质参数进行了空间结构分析,结果显示,污染物集中在湖岸线附近不易向湖中央扩散,各水质参数空间分布差异性较大,且空间结构特征极为相似,不同尺度之间有差异性。同时,由于采样密度和范围的限制,更细微和更大尺度的空间结构特征尚不能得以表述。最后,还讨论了太湖水质参数的空间结构变异性。  相似文献   

12.
在2008年和2009年对杭州地区17个大中型水库进行了调查。结果表明:杭州地区大中型水库水质不容乐观,按照单因子指标评价法,只有3个水库符合Ⅱ类水体标准,2个水库符合Ⅲ类水体标准,2个水库为Ⅳ类水体,3个水库为Ⅴ类水体,其余7个水库均为劣Ⅴ类水体,定类指标均是总氮。根据综合营养状态指数结果:丰水期2个水库处于贫营养状态,13个水库处于中营养状态,2个水库处于轻度富营养状态;枯水期16个水库处于中营养状态,1个水库处于中度富营养状态。总氮和总磷作为营养物质是这些水库富营养化的主要影响因素。位于山区源头地区的水库水质最好,位于平原城乡附近的水库其次,位于城市下游及城区附近的水库水质最差  相似文献   

13.
The use of ultra filtration in trace metal speciation studies in sea water   总被引:1,自引:0,他引:1  
During this work, size fractionation technique "ultra filtration" is used in speciation studies of trace elements in the coastal sea water. Filtration is the most commonly used method to fractionate trace metal species, but often only "dissolved" and "particulate" fraction. The purpose of the present study is to determine colloidal and suspended particulate concentrations of Fe, Zn, Cu, Ni, and Mn in sea water. Suspended particulate matter were separated in three different size groups namely (>2.7 microm, <2.7->0.45 microm and <0.45->0.22 microm) by suction filtration using cellulose acetate and nitrate filter membranes. Thereafter to concentrate the solution with colloidal particle <0.22 microm-1.1 nm (0.5 k Nominal Molecular Weight cut-off Limit {NMWL}), the solution obtained from filtration through <0.22 microm, is sequentially passed through the ultra-filtration membranes having pore diameters of 14 nm (300 k NMWL), 3.1 nm (50 k NMWL), 2.2 nm (30 k NMWL), 1.6 nm (10 k NMWL) and 1.1 nm (0.5 k NMWL) by using Stirred Ultra-filtration Cells, operating in concentration mode. The concentration of Fe, Zn, Cu, Ni, and Mn were measured in suspended and dissolved fraction by ion chromatography, ICP-AES and Atomic Absorption Spectrometer. The salinity of the solution in various dissolved fractions of sequential filtration varies between 30.89-34.22 parts per thousand. The maximum concentrations of colloidal Zn, Cu, Ni and Mn in dissolved fraction were in <2.2->1.6 nm fraction. In case of Fe, colloidal fractions <2.2->1.6 nm and <1.6-<1.1 nm shows higher concentration. The concentration of Zn, Cu, Ni and Mn increase with decrease in size in suspended particulate matter, while the reverse is observed in case of Fe. This size separation data that specifies the partitioning of metals between dissolved and suspended solid phases is necessary for developing physically based models of metal transport in aquatic system.  相似文献   

14.
鄱阳湖流域农村生活区面源污染特征及其影响   总被引:5,自引:0,他引:5  
农村生活区水环境是流域水环境的重要组成部分。鄱阳湖流域是我国的重要农业生产区,农村人口众多,未经过处理的生活污水、生活垃圾和固体废弃物、分散畜禽养殖污染由于无序排放导致了鄱阳湖流域河湖水质下降,湖泊富营养化指数升高。通过采用污染物当量算法对鄱阳湖流域农村生活区面源污染估算,分析了1991~2011年农村生活污染现状及其趋势,并分析了鄱阳湖河湖水质变化趋势及其在农村生活区面源污染中的影响因子。研究结果表明:(1)1991~2011年,鄱阳湖流域农村人口、生活污染、生活垃圾和固体废弃物污染、分散畜禽养殖污染不断增加,其中农村生活污水污染物排放量、TN、TP和COD排放量增长了1268%,年平均增长量分别为036、002、1681和021万t;固体废弃物排放量、TN和TP排放量增加了1268%,年增长量分别为362、076和080万t;分散畜禽养殖污染TN、TP和COD的含量分别增长了9913%、6384%和7227%,年均增长量分别为022、003和009万t;(2)2000年以来,鄱阳湖流域河湖水质呈下降趋势,其中鄱阳湖湖泊的水质和富营养化指数下降趋势分别在001和005水平上具有显著性;(3)鄱阳湖流域农村生活区面源污染对流域水环境具有一定的影响,其中分散畜禽养殖污染的影响相对较大  相似文献   

15.
Coastal marine eutrophication assessment: a review on data analysis   总被引:2,自引:0,他引:2  
A wide variety of data analysis techniques have been applied for quantitative assessment of coastal marine eutrophication. Indicators for assessing eutrophication and frequency distributions have been used to develop scales for characterizing oligotrophy and eutrophication. Numerical classification has also contributed to the assessment of eutrophic trends by grouping sampling sites of similar trophic conditions. Applications of eutrophication assessment based on Principal Component Analysis and Multidimensional Scaling have also been carried out. In addition, the rapid development of Geographical Information Systems has provided the framework for applications of spatial methods and mapping techniques on eutrophication studies. Satellite data have also contributed to eutrophication assessment especially at large scale. Multiple criteria analysis methods can integrate eutrophication variables together with socio-economic parameters providing a holistic approach particularly useful to policy makers. As the current concept of eutrophication problems is to be examined as part of a coastal management approach, more complex quantitative procedures are needed to provide a platform useful for implementation of environmental policy. The present work reviews methods of data analysis used for the assessment of coastal marine eutrophication. The difficulties in applying these methods on data collected from the marine environment are discussed as well as the future perspectives of spatial and multiple criteria choice methods.  相似文献   

16.
Water pollution, evident by negative values of redox potential in waters, occurs at the lagoonal coast located near the densely populated area of Fongafale Islet on Funafuti Atoll, Tuvalu, Central Pacific. Sediment microbial quinone analysis revealed that these coastal sediments exhibit 2.7–10.4 times more microbial biomass, significantly different microbial community structure and low microbial diversity, when compared to an undisturbed natural coastal sediment. Thus, the pollution is chronic. By considering the total land use/coverage on the islet, the situation of septic tank installations, temporal changes in water redox potential and Escherichia coli numbers in the coastal waters and the spatial distribution of acid volatile sulfide in the sediments, we conclude that domestic wastewater is the primary source of pollution. This pollution is proposed to occur via the following mechanism: during ebb tides, domestic wastewater leaking from bottomless septic tanks and pit toilets run off into the lagoonal coast. Tide changes control the pollution load of domestic wastewater.  相似文献   

17.
18.
Increased nitrogen (N) and phosphorus (P) inputs are major causes of eutrophication in the coastal waters of the Black Sea. The objective of this study is to analyze the past and future trends in river export of nitrogen and phosphorus to the coastal waters of the Black Sea and to assess the associated potential for coastal eutrophication. The Global NEWS-2 (Nutrient Export from WaterSheds) model was used for this purpose. Currently, most eutrophication occurs in the North Black Sea and the Azov Sea. In the future, however, this may change. We analyzed trends up to 2050 on the basis of the Millennium Ecosystem Assessment (MEA) scenarios. The results indicate that nutrient loads in rivers draining into the North Black Sea and the Azov Sea may decrease in the coming decades as a result of agricultural trends and environmental policy. However, in these scenarios, the targets of the Black Sea Convention are not met. In the South Black Sea, there is currently little eutrophication. But this may change because of increases in nutrient inputs from sewage in the future.  相似文献   

19.
This paper presents a general, process-based dynamic model for coastal areas for radionuclides (metals, organics and nutrients) from both single pulse fallout and continuous deposition. The model gives radionuclide concentrations in water (total, dissolved and particulate phases and concentrations in sediments and fish) for entire defined coastal areas. The model gives monthly variations. It accounts for inflow from tributaries, direct fallout to the coastal area, internal fluxes (sedimentation, resuspension, diffusion, burial, mixing and biouptake and retention in fish) and fluxes to and from the sea outside the defined coastal area and/or adjacent coastal areas. The fluxes of water and substances between the sea and the coastal area are differentiated into three categories of coast types: (i) areas where the water exchange is regulated by tidal effects; (ii) open coastal areas where the water exchange is regulated by coastal currents; and (iii) semi-enclosed archipelago coasts. The coastal model gives the fluxes to and from the following four abiotic compartments: surface water, deep water, ET areas (i.e., areas where fine sediment erosion and transport processes dominate the bottom dynamic conditions and resuspension appears) and A-areas (i.e., areas of continuous fine sediment accumulation). Criteria to define the boundaries for the given coastal area towards the sea, and to define whether a coastal area is open or closed are given in operational terms. The model is simple to apply since all driving variables may be readily accessed from maps and standard monitoring programs. The driving variables are: latitude, catchment area, mean annual precipitation, fallout and month of fallout and parameters expressing coastal size and form as determined from, e.g., digitized bathymetric maps using a GIS program. Selected results: the predictions of radionuclide concentrations in water and fish largely depend on two factors, the concentration in the sea outside the given coastal area and/or adjacent coastal areas and the ecological half-life of the radionuclide in the sea. Uncertainties in these factors generally dominate all other uncertainties, e.g., concerning the surface water retention time, the settling velocity of the particulate fraction, the distribution coefficient regulating the fluxes in dissolved and particulate phases, the catchment area influences and the factors regulating biouptake and excretion of the radionuclide in fish. This means that the conditions in the sea are of paramount importance for the conditions in the coastal area, even for relatively enclosed coastal areas. This coastal model may be regarded as a tool for testing working hypotheses on the relative roles of different processes in different coastal areas. Such information is essential for getting realistic expectations of various remedial measures, such as coastal dredging discussed in this work.  相似文献   

20.
南四湖农业面源污染现状及控制措施   总被引:1,自引:0,他引:1  
近年来南四湖水质污染严重,农业面源污染是导致水体污染和富营养化的最主要因素;阐述了南四湖流域种植业、养殖业及农村生活污染三大污染源现状和危害;总结了国外对农业面源污染控制措施及研究动态,重点评述了农业面源污染的来源解析方法,提出了农业面源污染需要进一步研究的方向,对南四湖农业面源污染的研究具有一定的指导意义。  相似文献   

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