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1.
Lead isotopes in environmental sciences: a review   总被引:15,自引:0,他引:15  
Lead (Pb) isotopic analyses proved to be a very efficient tool for tracing the sources of local and global Pb pollution. This review presents an overview of literature published on the use of Pb isotopic analyses of different environmental matrices (atmospheric aerosols, lichens, tree rings, peat deposits, lake, stream, marine sediments, soils, etc.). In order to gain more insight, the isotopic compositions of major sources of Pb in the environment as determined by several authors are described in detail. These include, above all, the former use of leaded gasoline, coal combustion, industrial activities (e.g., metallurgy) and waste incineration. Furthermore, this review summarises analytical techniques (especially ICP-MS) used for the determination of Pb isotopes in environmental samples.  相似文献   

2.
首先参照投入—产出比,利用环保财政投入占GDP比重与环境污染综合指数之比对各区域环境财政政策治污效应系数进行测算,按系数值域把中国30个省(市)分成两个区域,区域1包括北京、甘肃、贵州等19个省市,区域2包括上海、浙江、福建等11个省市。其次分析环境财政政策、环境税收政策和中国式环境分权的治污效应并分区检验,最后对中国式环境分权和经济发展水平的门槛效应进行实证检验。结果表明:环境财政政策治污效应显著,区域1财政政策取得了更好的治污效果,中国目前车船税、城市维护建设税、土地使用税、耕地占用税、资源税及排污费等"近似"环境税种总体治污效应不显著,中国式环境分权与污染物排放显著正相关,中国式环境分权和经济发展水平对财政政策的治污效应具有显著的门槛效应,当中国式环境分权度低于-0.164、经济发展水平低于4.174时,环境财政政策具有更好的治污效果。样本期内以中国式环境分权为门槛变量时,有安徽、广西等15%的观测值位于低门槛区域,以经济发展水平为门槛变量时,有贵州、云南等10%的观测值位于低门槛区域。中国目前的能源消费结构和工业结构是加剧环境污染的重要原因,城镇化和对外开放在一定程度上助推了高污染和高排放。鉴于此应加大环境保护财政支出,提升环保财政支出占GDP的比重,单独开征环境保护税种,中央政府适度地环境集权,全面提升环境质量。  相似文献   

3.
环境规制是实现农业面源污染减排的重要手段,而科学合理地划分环境管理权力是夯实环境规制减排绩效的制度基础。厘清环境分权、环境规制与农业面源污染三者之间的关系对优化环境管理体制和促进农业绿色发展具有重要的理论与现实意义。鉴于此,文章将环境规制、环境分权和农业面源污染纳入同一分析框架,基于2005—2017年省际面板数据,构建动态面板模型和面板门槛模型,实证考察了环境分权、环境规制与农业面源污染的内在联系。研究结果显示:①环境规制是抑制农业面源污染的重要手段;环境分权、环境监察分权和环境监测分权对农业面源污染具有显著的正向作用,环境行政分权对农业面源污染则表现为负向作用。②环境事务管理权力的下放将恶化环境规制的农业面源污染减排效应,引发“绿色悖论”效应,其中环境监察分权和环境监测分权的影响尤为突出。③从区域层面来看,中西部地区环境事务管理权力下放引发的“绿色悖论”效应显著,而东部地区则不显著。④环境规制对农业面源污染的影响随环境分权程度的变化呈现出门槛特征。伴随环境分权程度的提高,环境规制对农业面源污染的影响由“援助之手”转为“攫取之手”。因此,为解决日益严重的农业面源污染,应制定差异化的环境分权策略。一方面,环境行政权力应适当下放,而环境监察和环境监测权力要逐步上移;另一方面,进一步压缩中西部地区环境政策自由裁量空间,加大农业环境考核与监督力度。同时,建立长期动态农业面源污染监测体系,形成联防联控治理格局。  相似文献   

4.
以往研究已经证明海洋经济发展中产生的污染对海洋环境质量的变化没有显著性影响,海洋污染物的主要来源是陆地,海洋环境与陆域经济之间存在着较为密切的关系,但关于陆域产业结构演进对海洋环境影响的研究非常少见,加深该研究对推动海洋环境改善具有重要的意义。利用VAR模型和Tapio脱钩模型,研究2001~2017年间长江流域和东海沿岸地区的产业结构高度化和产业结构合理化对东海海域的海洋环境的动态冲击,借助它们的脱钩状态证实该影响。研究结果显示:(1)陆域产业结构高度化有利于海洋环境改善,其原因包括产业间优势地位的更替和产业内部的技术创新;陆域产业结构合理化的发展存在波动性,导致它对海洋环境的影响不够显著;一部分海洋污染物可以通过海水自身的净化能力而消解,残存污染给海洋环境带来了不利影响。(2)在2002~2017年,东海的海洋环境与长江流域和东海沿岸地区的产业结构高度化、合理化分别表现为"大幅变化-稳步变化-脱钩持续"、"剧烈变化-起伏波动-脱钩持续"的脱钩变化规律,该脱钩分析结果证实了陆域产业结构演进对海洋环境的影响。  相似文献   

5.
借鉴Islam的研究思路,构建农业面源污染影响因素分解的理论模型。并利用1990~2010年省际面板数据进行实证研究,探讨农业面源污染演变的内在驱动机制,以期为农业面源污染控制和管理提供理论依据。主要研究结论如下:(1)农业面源污染演变受规模效应、结构效应和减污效应的共同影响;(2)规模效应对农业面源污染的影响为正,这说明农业生产规模和农村人口规模的扩大会增大农业面源污染的排放。结构效应的两个重要方面(经济作物比重的提高和畜禽养殖业产值比重的提高)都会导致农业面源污染的加剧。技术进步和经济发展的减污效应开始初步发挥,二者都能有效减少农业面源污染,这为实现农业生产与生态环境的协调发展提供了可能  相似文献   

6.
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   

7.
改革开放以来,外商直接投资(FDI)的涌入为中国经济发展注入了新活力,并成为中国经济高速增长的重要引擎之一。然而,随着康菲石油渤海漏油事故、江苏启东王子造纸排污和阿玛尼污染投诉等涉外污染事件报道频出,学术界对于FDI涌入可能带来的负面环境效应表现出一定担忧。现有文献多聚焦于整体层面的FDI环境效应检验,而对其区域差异及原因产生机制的系统探究并不多见。为此,本文从理论判断和命题推演出发,利用2003—2014年中国省际面板数据,以改进熵值法拟合环境污染综合指数,并构建普通面板模型,实证检验了FDI流入对中国环境污染的影响及其区域差异。结果表明,总体而言,"污染光环"假说在中国基本成立,即FDI流入在一定程度上改善了中国环境质量,但不同地区FDI的环境效应有所不同,其主要表现为沿海和内陆地区FDI具有显著的"污染光环"效应,且前者强于后者,而沿边地区FDI具有不明显的"污染天堂"效应。在此基础上,构造面板门槛模型,进一步系统考察了FDI对中国环境污染影响的4种主要吸收能力因素的门槛效应。门槛回归结果表明,FDI对中国环境污染的影响显著存在基于经济发展、环境规制、人力资本和金融发展水平的双门槛效应。经济发展、人力资本和金融发展水平越高,FDI的"污染光环"效应越明显,而适度的环境规制才更有利于FDI环境技术溢出的发挥。基于此,本文建议应进一步全方位地提高对外开放水平,一如既往地积极引进并监督FDI;同时地方政府也需认清地区发展的不平衡性,进而采取差异化的引资政策。  相似文献   

8.
黄浦江上游地区水环境污染负荷特征   总被引:1,自引:0,他引:1  
通过调查黄浦江上游地区的水环境污染来源、污染负荷及其特征,为管理部门控制污染、提高上游地区水环境质量提供科学依据。调查中了解到污染源种类主要有4类:工业、事业、生活和畜禽污染源;水源保护区内年用水量为22196万t.污水量为17755万t/a,其中工业污染源352个,排放量占46.3%,事业污染源4108个。排放量占22.3%,生活污水排放量占30.6%.畜禽污水排放量占0.8%;黄浦江上游水源保护区污染源排放去向主要分4种:直排河道(占40.4%),进入市政泵站后排出(占3.9%)。经污水处理厂处理后排出(占20.5%),通过合流污水收集系统排出(占35.3%)。根据黄浦江上游地区水环境污染负荷特征,建议黄浦江上游区域进一步调整和完善不同区域的功能定位,优化产业结构和布局,构建利于水源保护的区域发展模式和格局;通过采取污染控制和生态环境建设并重的一系列措施,有效抑制生态环境恶化趋势,促进黄浦江上游上游水环境质量的改善。确保上海市的饮用水安全。  相似文献   

9.
The advantages of using radionuclides for laboratory studies of environmental processes include the wide range of element concentrations that can be studied, the capability to simultaneously study several isotopes in a single experiment, the direct applicability to the behaviour of radioactive waste or fallout, and the ability to study the mechanisms, reversibility and kinetics of environmental reactions under controlled conditions. These attributes are demonstrated using specific examples drawn from case studies in Australia, including radionuclide fallout onto tropical soils, the association of trace metals with harbour sediments and the behaviour of uranium in natural and contaminated systems.  相似文献   

10.
ABSTRACT

Interaction of environmental pollution between peripheral areas has become a central topic in the field of resources and environment but little is known about the actual impact on peripheral areas in the current literature. This paper sets out a simultaneous equation model to investigate the spillover effect of environmental pollution between China’s peripheral areas utilizing the panel data of 218 cities in China. Making use of indicators for measuring the impact on environmental pollution, it identifies that environmental pollution between cities of China has a significant two-way spillover effect. After standardization of variables, it is found that the spillover effect of peripheral areas on urban environmental pollution cannot be neglected. Nearly, a third of the environmental pollution level in a city is induced by the environmental pollution in peripheral areas. If the indicator of environmental pollution in peripheral areas is missing, wrong conclusions will be drawn. Therefore, government should shift the emphasis of environmental regulation from local to global, and improve the overall environmental quality through coordinated management of regional environment.  相似文献   

11.
水电工程的建设对区域环境会产生不可逆转的重大扰动,生态环境监测与预警作为大型水电工程建设的重要环节,为工程区域环境问题分析与研究提供详实的数据支撑,对区域生态环境的修复至关重要。以向家坝水电站为例,分析水电工程建设对区域环境产生扰动的特点,结合产生扰动的各环境要素,构建工程施工区环境监测体系。收集、整理相关监测数据,采用环境因子综合评价法对监测的相关数据进行分析和评价,结合各种环境因子的现状以及变化过程、总结区域环境总体状况的变化规律及空间分布。结果表明:自2007年工程大规模动工以来,区域的生态脆弱度大幅度升高,2008年达到顶峰,自2009年起环境开始改善,保持优于2007、2008年的状况;最脆弱区域为主体工程和云天化生产区交接地区,低度脆弱区域为河流及工程量少的加工工程区域;工程扰动最大的区域、当地工业区及交通枢纽集中地带是建设区环境最脆弱的区域,工程建设、工业及交通是建设区的主要扰动因素  相似文献   

12.
近年来,收入差距扩大与环境质量恶化成为许多国家同时面临的问题,也让一些经济学家开始思考,这两者之间是否存在关联。继20世纪90年代环境库兹涅茨曲线提出以来,一些研究发现不仅收入的绝对水平会对环境质量产生影响,收入差距对环境质量也有影响。本文对这一课题的理论研究进行了梳理,发现现有理论中收入差距对环境质量的影响途径主要有三条。第一条途径是消费者途径,即收入差距影响着以消费为主的个人经济行为,进一步影响着社会消费总量和消费结构,及其过程中产生的污染总量。第二条途径是企业途径,即认为收入差距的扩大会削弱环保型产品的正外部性,不利于环保技术的创新活动,对未来环境质量的改善产生动态影响。第三条途径是政府途径,即认为收入差距会影响相关的环境政策方式与强度选择;而且在不同的社会政策决策机制下,收入差距对环境政策的影响也是不同的,现有的社会决策机制分析框架主要有两种——权利权重型社会决策规则和简单多数规则。此外,本文还对现存的主要实证研究进行了总结,发现大多数研究结论都支持收入差距对环境质量存在着影响,但这种影响并不是线性的。一方面,收入差距对环境的影响与研究的污染物种类有关,大多数研究都显示,收入不平等对CO 2排放和土壤污染存在着负向影响,但有关收入差距对空气污染和水污染影响的研究结论并不统一或并不显著。另一方面,这种影响还与经济发展水平相关,在高收入国家与低收入国家是不同的,存在着阈值效应。最后本文总结了针对中国的研究现状,讨论了其在我国的适用性。  相似文献   

13.
土地利用快速变化对水环境带来较大影响,定量分析土地利用与水环境污染的关系是土地利用结构调整的重要依据。利用3S技术,通过SWAT模型对1983年与2012年昌江流域的水量和水质模拟,分析了土地利用时空变化,结合氨氮、总磷模拟数据,定量分析了土地利用变化下该流域的水环境污染负荷。研究结果表明:该区域林地、草地、水域、城镇及建设用地呈增加趋势,耕地则呈减小趋势。林地占比最大,为70%左右,其次为水田。水田为水环境非点源负荷贡献的第一大来源,且其占流域略多于20%的面积,贡献了该区域总磷总量的53.48%~57.01%和氨氮总量的51.86%~56.57%;农业耕作以25%的地类面积,贡献了60%~65%的非点源污染负荷;旱地的单位面积贡献污染负荷高于林地及城镇及建设用地,表明农业非点源污染是该区域水环境非点源污染的主要来源。  相似文献   

14.
In the control of pollution, two apparently important facts are often negelected: (1) removal of a particular pollutant from a particular source and location may merely result in transforming it into a pollutant, or pollutants of different forms, in other locations; (2) the activity of pollution control itself requires inputs, the production of which may generate additional pollutants. In order to achieve positive environmental control, these two facts must be considered in selecting control processes and in determining optimum control standards. It is necessary that an integrated approach to pollution control be taken, making allowances for ecological inter-relations. As practiced today, pollution control is handled as separate problems of disposing gas, liquid and solid wastes. This paper proposes a model for evaluating the total environmental impact of a pollution control process or method. Theoretical criteria for determining an optimum control level with or without resource constraint are also derived.  相似文献   

15.
农业面源污染形成机制:理论与实证   总被引:8,自引:0,他引:8  
在对我国农业面源污染核算及其时空演变特征分析的基础上,构建农业面源污染形成机制分析框架,并利用省际面板数据进行实证分析。主要研究结论如下:①1990-2006年我国农业面源污染对生态环境的压力呈现增加的趋势,主要分布在人口众多、农业集约化程度较高的地区。②农业面源污染形成的一般机制是:经济发展导致农产品需求结构、农业结构的变动等都会对农业面源污染产生的环境因子产生影响,进而导致农业面源污染产生量的差异;对农产品消费数量的增多和对耕地的消耗增大,农业生态系统面临更大的生产集约程度,在很大程度上加大了农业面源污染;经济发展同时也导致公众对高质量环境的需求增多,环保意识也大大提高,为农业面源污染管理政策提供了有效执行土壤,另外,经济增长也为加大环境投资和先进技术的应用提供基础,可能减少农业生产对环境的压力;③实证研究表明,产业结构的演化、技术进步、环境管理制度等方面是影响农业面源污染的重要因素,应是农业面源污染控制和管理政策创新的重点。  相似文献   

16.
鄱阳湖小流域农村面源污染严重,环境问题不断加剧。通过背景值调查与污染源解析,显示农村生活和种植业是鄱阳湖小流域农村面源污染的主要来源。采取集成式BMPs模式,将源头控制与末端治理相结合,充分利用当地优势,合理搭配植物缓冲带、沟渠湿地、人工湿地,兼性塘等,实现氮、磷流失的有效拦截,达到有效控制示范区小流域农村面源污染目的,从而为鄱阳湖农村面源污染控制提供借鉴。结果表明: BMPs系统污染物去除能力高,运行成本低。系统单位面积削减总量分别为CODcr 71017 kg、SS 11491 kg、TP 408 kg、TN 3593 kg、NO-3 N 474 kg、NH+4 N 1918 kg,而运行成本不到01元/t。整个系统中尤以表面流人工湿地减污效果最好,耐负荷冲击能力最强。沟渠湿地整体去污能力不低,但耐冲击负荷能力弱,易受外界因素的影响。为加强减污效果,可通过完善生态系统尤其是挺水性植物加以改进  相似文献   

17.
Environmental problems are becoming increasingly severe in China with industrial discharges and household sewages being the main sources of water pollution in the country. For example, in the case of Taihu Lake, more than half of the total phosphorus in the lake comes from household sewage. While industrial pollution can be treated through technology innovation and controlled by environmental regulations and laws, decreasing household sewage relies entirely on residents. Raising public environmental awareness therefore is essential for ensuring effective environmental improvement and protection. A quantitative assessment of public awareness can inform policy and decision makers; however, not many such studies have been conducted. Changes in the awareness levels in response to a major environmental pollution incident are of particular interest because of the people’s first-hand experience of the triggered consequences. The present paper establishes a system of indicators for the assessment of public environmental awareness. Combined with a fuzzy matter-element analysis method, a model is set-up to quantitatively assess the public environmental awareness. The model is then applied to assess the environmental awareness of the residents of Wuxi City after its major lake Taihu suffered a severe algae bloom in 2007. This study examines whether this serious environmental incident affected people’s environmental awareness and to what degree. The findings show that the matter-element model is capable to resolve well the fuzziness of the ranking affiliation and classification of subjective perceptions, such as public environmental awareness. They show that this environmental incident has had significant positive impacts on the environmental awareness of Wuxi residents. The paper concludes with recommendations related to raising public environmental awareness.  相似文献   

18.
Biological activity and environmental impact of anionic surfactants   总被引:8,自引:0,他引:8  
The newest results concerning the biological activity and environmental fate of anionic surfactants are collected and critically evaluated. The chemical and physicochemical parameters related to the biological activity and the field of application are briefly discussed. Examples on the effect of anionic surfactants on the cell membranes, on the activity of enzymes, on the binding to various proteins and to other cell components and on their human toxicity are presented and the possible mode of action is elucidated. The sources of environmental pollution caused by anionic surfactants are listed and the methods developed for their removal from liquid, semiliquid and solid matrices are collected. Both the beneficial and adversary effects of anionic surfactants on the environment are reported and critically discussed. It was concluded that the role of anionic surfactants in the environment is ambiguous: they can cause serous environmental pollution with toxic effect on living organisms; otherwise, they can promote the decomposition and/or removal of other inorganic and organic pollutants from the environment. The relationship between their chemical structure, physicochemical parameters, biological activity and environmental impact is notwell understood. A considerable number of data are needed for the development of new anionic surfactants and for the successful application of the existing ones to reduce the adversary and to promote beneficial effects.  相似文献   

19.
The potentially deleterious presence of ore-derived Pb within riverine environments has been a long-term impact of industrial and anthropogenic activity in general. The surface drainage network has been widely established as a key transport mechanism and storage environment for anthropogenically-derived Pb and other potentially harmful trace metals. Lead isotopes ((204)Pb, (206)Pb, (207)Pb, (208)Pb) have been utilized as a geochemical tracer of Pb origin in a variety of environmental media, notably in atmospheric aerosols. However, given the relative complexity of dispersal processes within riverine environments, the use of Pb isotopes as geochemical tracers has been relatively limited and it is only relatively recently that a growing body of research has applied Pb isotopes to provenancing fluvially-dispersed Pb. This paper seeks to synthesize the developments in the use of Pb isotopes within riverine environments. In doing so it outlines the Pb-isotope fingerprinting technique and associated analytical developments, and assesses the application of Pb isotopes in establishing the origin and dispersal mechanisms of anthropogenically- and geogenically-derived Pb at a range of temporal and spatial scales. Of particular importance are the approaches quantifying source inputs using Pb isotopic signatures and the challenges faced, and options available in quantifying source inputs at the catchment scale; where Pb may be sourced from a variety (n=>2) of sources. The Pb isotopic signature of contemporary riverine Pb loads is shown to reflect a spatially complex influence of mineralization chemistry, anthropogenic activity as well as the hydro-morphological controls exerted upon Pb release, dispersal and storage. In relation to this, the long-term environmental legacy, and its influence upon Pb fingerprinting studies, of tetra-ethyl Pb, sourced from the combustion of leaded-petrol is also discussed. Finally, this paper places the use of Pb isotopes in the context of recently developed Cu and Zn isotopic fingerprinting techniques and assesses the role of Pb, Cu and Zn isotopes in a multi-proxy approach to geochemical tracing.  相似文献   

20.
平原河网地区非点源污染风险差异化分区防控研究   总被引:1,自引:0,他引:1  
土地利用优化和空间防控策略对非点源污染风险控制及水环境质量的改善具有重要意义。本文以太湖流域典型平原河网地区-上海市青浦区为研究对象,将灰色线性规划模型与最小累积阻力模型相结合,以控制非点源污染风险和增加经济效益、生态效益为目标,进行土地利用结构优化与空间分区防控研究,在空间上划设了水资源保育区、水资源重点防护区、非点源污染一般阻控区、非点源污染中等阻控区及非点源污染重点阻控区,并针对不同分区提出具有针对性的防控措施。与2012年相比,预测2020年优化防控方案下,可减少总氮、总磷的输出10.96%和41.33%。由此表明,优化土地利用结构和构建空间差异化防控机制是有效调控非点源污染风险,实现区域可持续土地利用,促进经济发展和保证生态环境安全的有效途径。  相似文献   

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