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1.
Abstract

The near shore coastal and marine environment of several Caribbean islands is their most biologically productive and economically important zone. However, almost all landbased activities possess the real potential of degrading the quality of near shore waters and ultimately diminishing the utility of the marine resource. This condition is largely attributed to the individual smallness of the islands and their geographic proximity to each other.

Available sanitary water quality data from across the region indicated that while recreational areas are in general safe for water contact activities, bacterial densities in excess of several international criteria are consistently recorded in harbours. Organochlorine pesticide residues were generally in the 5 ng l?1 range in unfiltered sea water but were significantly higher (1–100) ng g?1 in limited samples of sediment and biota. Additional data requirements to gain further insight into the current state of the Caribbean environment are also identified.

A summary of the major land based sources of marine pollution (including sewage, industrial effluents and agricultural run-off) in the insular Caribbean is presented.  相似文献   

2.
The pollution of the marine environment caused by land-based sources threatens or impairs the health of the ecosystems and the value of human uses of the coastal waters. the Contracting Parties to the Convention for the Protection and Development of the Marine Environment of the Wider Caribbean Region agreed to take all appropriate measures to prevent, reduce and control pollution. in the first meeting of the Contracting Parties, the development of a protocol on the control of marine pollution from land-based sources was recommended as a measure to protect the marine environment.

A small group of experts from the Caribbean Region formulated a strategy for controlling land-based sources of marine pollution. Due to the diverse nature, resources and capabilities of the countries comprising the Region, the pollution control strategy suggested by the group of experts included the following techniques or their most appropriate combination: (1) pollution prevention measures, (2) effluent limitations, (3) water quality limitations, (4) environmental planning, and (5) best management practices. the desirable control strategy should be based on a system of discharge permits in the case of point source pollution, which includes effluent and water quality limitations. the technology based effluent limitations could be applied as a short-range strategy to control pollution from industrial and domestic point source discharges. the use of water quality standards could become part of a long-range strategy for controlling point sources. for nonpoint sources, it would be virtually impossible to develop effluent limitations. Thus, the implementation of best management practices and effective environmental planning would be the most reasonable control strategy for non-point sources. However, pollution prevention measures could consist of a “black list” of substances that should be completely banned, and a “grey list” for those that should be strictly limited. These lists should be adopted or appropriately modified for the conditions of the Wider Caribbean Region.

The development of control based on the water quality of the receiving body of water involves the collection and analysis of effluent and ambient data to develop water quality based permit limits and to assess compliance with these permits. Finally, any marine pollution control strategy developed by the countries of the Region should be mutually agreed upon and implemented within a period of ten years from the ratification of a protocol on land-based sources of marine pollution.  相似文献   

3.
外源性污染对太湖梅梁湾水质影响的定量化   总被引:4,自引:0,他引:4  
通过太湖的水量水质数学模型,模拟了梅梁湾内主要的入湖污染源———直湖港、武进港和梁溪河排入的污染物质的迁移、转化规律;分析了梅梁湾中梅园、小湾里、闾江口、拖山4个监测点水质浓度受直湖港、武进港和梁溪河排污影响程度的大小;并分别建立了监测点污染物浓度与排污口排污量的响应关系曲线和响应关系表达式。通过这些结论可以方便的定量的计算出在排污口排污量发生变化的情况下监测点水质浓度的变化量,为合理控制外源污染物质的入湖量提供了技术支持。  相似文献   

4.
Abstract: Marine protected areas (MPAs), including no‐take marine reserves (MRs), play an important role in the conservation of marine biodiversity. We document the status of MPAs and MRs in Latin America and the Caribbean, where little has been reported on the scope of such protection. Our survey of protected area databases, published and unpublished literature, and Internet searches yielded information from 30 countries and 12 overseas territories. At present more than 700 MPAs have been established, covering more than 300,000 km2 or 1.5% of the coastal and shelf waters. We report on the status of 3 categories of protection: MPAs (limited take throughout the area), MRs (no‐take throughout the area), and mixed‐use (a limited‐take MPA that contains an MR). The majority of protected areas in Latin America and the Caribbean are MPAs, which allow some or extensive extractive activities throughout the designated area. These 571 sites cover 51,505 km2 or 0.3% of coastal and shelf waters. There are 98 MRs covering 16,862 km2 or 0.1% of the coastal and shelf waters. Mixed‐use MPAs are the fewest in number (87), but cover the largest area (236,853 km2, 1.2%). Across Latin America and the Caribbean, many biogeographic provinces are underrepresented in these protected areas. Large coastal regions remain unprotected, in particular, the southern Pacific and southern Atlantic coasts of South America. Our analysis reveals multiple opportunities to strengthen marine conservation in Latin America and the Caribbean by improving implementation, management, and enforcement of existing MPAs; adding new MPAs and MRs strategically to enhance connectivity and sustainability of existing protection; and establishing new networks of MPAs and MRs or combinations thereof to enhance protection where little currently exists.  相似文献   

5.
大气污染源监测采样技术   总被引:3,自引:0,他引:3  
依据气态污染源共同的排放特性及平均排放浓度,排放速率的概念,导出气态污染源监测中常用的三种采样方法:积分法、分部积分法、有限加合近似法。根据分析化学的要求,提出样品采集时间的设计方法。由此得出不同类型排放源的监测时间和采样频率确定方法。  相似文献   

6.
研究了湖北省潜江市农村6类食品中农药的残留情况,采样测定结果表明,在被检食品中有机氯农药污染普遍存在,但残留量均低于最大残留限量(MRL),以植物油残留量为最大;有机磷农药残留只在蔬菜中检出,检出率以根菜类为最大,叶菜类次之,果菜类和花菜类最小;菊酯类农药残留较少;杀菌剂多菌灵残留未检出。  相似文献   

7.
近年来太湖流域局部水质状况有所改善,但太湖藻型生境条件还未根本改变,水污染防治任务依然艰巨。确保太湖湖体水质稳定达标,尤其是加强对太湖重点湖区和水源地重点污染物的调查研究十分重要。在此背景下,本文调研了太湖重点湖区和水源地水质概况、藻毒素污染时空分布特征、环境影响因子和迁移转化规律,并总结了藻毒素的环境和健康风险研究的最新进展,指出了太湖西部湖区和饮用水源地的主要环境风险,以及未来太湖藻毒素污染相关研究需解决的关键技术问题,以期为促进太湖流域重点污染物的控制和治理,确保太湖饮用水源地安全提供有益借鉴。  相似文献   

8.
Ninety-nine human blood samples were collected from the riverine region of northern Sudan and the traditional and mechanized rain-fed areas of western and eastern Sudan, representing areas of limited pesticide use in Sudan. Blood samples were analyzed for organochlorine pesticides by gas liquid chromatography (GLC) followed by electron-capture detection (ECD). p,p′-DDE (a metabolite of DDT), heptachlor epoxide, β-hexachlorocyclohexane (β-HCH), and dieldrin were detected in all locations surveyed. The level of total organochlorine burden was highest in the traditional rain-fed area, followed by the mechanized rain-fed area, and the riverine area. A highly significant correlation was observed between total organochlorine blood burden and the age of the donors (r = 0.608**).  相似文献   

9.
简要介绍了玉环县五大河流环境质量现状,分析了造成了五大河流受污染的原因,并从环保的角度提出了建议项目指导性意见,以及分流域提出了五大河流的污染防治对策。  相似文献   

10.
天津市土壤风沙尘元素的分布特征和来源研究   总被引:8,自引:0,他引:8  
通过与土壤标准和背景值的比较分析了天津市土壤风沙尘元素的质量分数分布特征,通过富集因子法分析了天津市风沙尘元素的富集特征,进而说明天津市风沙尘元素的来源及其变化。结果表明,(1)Cr、Ni、Cu、Zn和As质量分数均有超过土壤标准的现象。(2)Ni、Cu、Pb、Zn和Ag超过背景值10倍以上,受到了人为污染。(3)粗颗粒中西青区的Pb元素,津南区的Ni元素和Pb元素以及细颗粒中东丽区的Ca元素和Zn元素,西青区的Cu、Pb,津南区的Cr、Ni、Pb等元素达到显著污染级别;各区粗细颗粒中的Ag元素污染级别最高,有的为极强烈污染;这些元素是典型的人为污染元素。(4)粗颗粒中只有Ca和Ni污染级别有所增加,细颗粒中只有Na、Ni、As等3种元素的富集因子略有增加。所以,天津市土壤风沙尘的治理重在控制人为来源的Ni、Cu、Pb、Zn、Ag、Cr和Ca等高污染元素。  相似文献   

11.
A systematic survey of organochlorine pesticides (OCPs) including hexachlorocyclohexane isomers (α-HCH, β-HCH, γ-HCH, δ-HCH and ΣHCH) and dichlorodiphenyltrichloroethane metabolites (p,p′-DDT, p,p′-DDE, o,p′-DDT, p,p′-DDD and ∑DDT) in soils along the north coastal areas of the Bohai Sea, China, has been lacking. In this study, 31 representative surface soil samples were collected along the north coastal and riverine areas of the Bohai Sea to characterise the potential for adverse effects of ∑HCH, ∑DDT and their individual isomers and transformation products. Concentrations of ΣHCH and ΣDDT in soils ranged from less than the limit of detection (1 ng · g?1 dw (mean: 3.5 ng · g?1 dw) and2 ng · g?1 dw (mean: 1.7 × 101 ng · g?1 dw), respectively. Compared with studies of OCPs in soils from other locations, concentrations of HCHs and DDTs observed in this study were moderate. Concentrations of OCPs observed in soils were generally less than proposed reference values. HCH residues were a mixture of historical technical HCH and current lindane sources. The pattern of DDTs was consistent with historical releases of technical DDTs. Selected soil physicochemical properties did not explain the sorption and/or partitioning of HCHs or DDTs.  相似文献   

12.
We examine the impact of pollution on biodiversity by studying the effect of coastal light pollution on the sea turtle population in the Caribbean. To this end we assemble a panel data set of sea turtle nesting activity and satellite-derived measures of nighttime light. Controlling for the surveyor effort, the local economic infrastructure, and spatial spillovers, we find that nighttime light significantly reduces the number of sea turtle nests. According to data on replacement costs for sea turtles raised in captivity, our result suggests that the increase in lighting over the last two decades has resulted in the loss of close to 1800 sea turtles in the Caribbean, worth up to $288 million. Incorporating our empirical estimates into a stage-structured population model, we discover that the dynamic effect of nighttime light on future generations of sea turtles is likely to be much larger, with a cost of approximately $2.8 billion for Guadeloupe alone. More generally, our study provides a new approach to valuing the cost of environmental pollution associated with species extinction.  相似文献   

13.
赣江流域中下游底泥中有机氯农药污染特征   总被引:2,自引:0,他引:2  
赵慈  刘小真  周立峰  梁越  赵信  洪桂平 《生态环境》2010,19(10):2419-2424
为了解赣江流域有机氯农药污染状况,采用索氏提取方法(Soxhlet Extraction,SE)和气相色谱法(GC-ECD),对所采集的18个底泥样品中10种有机氯农药(OCPs)的残留进行测定,并对其组分分布和来源进行了分析。结果表明,所有样品均检出10种有机氯农药,底泥中∑OCPs质量分数范围为11.813-39.197μg·kg-1,HCHs、DDTs质量分数范围分别为1.636-20.877μg·kg-1和5.590-14.092μg·kg-1,HCHs的质量分数低于DDTs,六氯苯(HCB)和七氯(Heptachlor)的质量分数相对较低,分别为0.229-6.940μg·kg-1和0.507-3.936μg·kg-1。组分分布特征分析表明,它们除了来自环境中的早期残留外,仍然具有大量新的外源HCHs和DDTs的输入,可能是新的林丹输入以及三氯杀螨醇的使用,这可能与近年来沿江农业的发展有关。  相似文献   

14.
Changes in soil pH, soil heavy metal forms, and the metabolic diversity of microbial communities were examined in soil samples collected in 1-mm increments from barley roots in soil contaminated with cadmium (Cd) and zinc (Zn) using a rhizobox system. Concentrations of exchangeable Cd and Zn increased near the roots owing to a decrease in soil pH. Conversely, the concentration of inorganically bound Cd and Zn decreased near the roots. Despite having the highest concentration of the most toxic exchangeable metals, the rhizosphere also had the highest bacterial and fungal metabolic activity and diversity when assessed using BIOLOG plates. Therefore, the promoting effects of root exudates on microbial activity could outweigh the adverse effects of Cd and Zn on microorganisms in the rhizosphere.  相似文献   

15.
This paper argues that the environmental changes witnessed in the past decade call for a new approach to environmental management; an approach based not on the principle of the assimilative capacity of the environment but on the precautionary principle, and the emerging preventive environmental paradigm. Uncertainties in scientific knowledge and complexities in ecological systems have presented specific failures of the assimilative capacity methodology. It is argued that these failures are not circumstantial in nature, nor are they the result of misapplication of science by scientists. Rather, they represent inherent problems in the use of the assimilative capacity concept in environmental management. The emergence of the precautionary principle is discussed and a formulation of the principle is presented. In conjunction with the operational approach of clean production, we believe that this principle offers a sounder basis for the prevention of marine pollution in the next decade.  相似文献   

16.
This paper argues that the environmental changes witnessed in the past decade call for a new approach to environmental management; an approach based not on the principle of the assimilative capacity of the environment but on the precautionary principle, and the emerging preventive environmental paradigm. Uncertainties in scientific knowledge and complexities in ecological systems have presented specific failures of the assimilative capacity methodology. It is argued that these failures are not circumstantial in nature, nor are they the result of misapplication of science by scientists. Rather, they represent inherent problems in the use of the assimilative capacity concept in environmental management. The emergence of the precautionary principle is discussed and a formulation of the principle is presented. In conjunction with the operational approach of clean production, we believe that this principle offers a sounder basis for the prevention of marine pollution in the next decade.  相似文献   

17.
在湖北保安湖采集主要食用鱼类(团头鲂、鲫鱼、草鱼)样品,通过测定鱼体中的重金属(Cr、Cd、As、Pb、Hg、Cu、Zn)和有机氯农药(六六六(HCHs)、滴滴涕(DDTs))含量,基于不同评估模型分析了这3种鱼的污染特征和健康风险。结果显示,鱼样中Cr、Cu、Zn、As、Cd、Pb和Hg的含量分别为1.03~1.13、0.93~1.66、22.80~31.54、0.08~0.49、0.004~0.007、0.040~0.050和0.03~0.06 mg·kg~(-1);鱼样中HCHs、DDTs的含量为5.94~38.04和5.99~38.38 ng·g~(-1)ww。根据国家规定的有毒有害物质限量标准,团头鲂和鲫鱼中As分别超标0.2和3.9倍;鲫鱼体内HCHs和草鱼体内DDTs含量分别超标0.9和2.8倍;其他鱼样重金属和有机氯农药含量均未超过标准限值。总体来看,鲫鱼重金属严重污染,重金属综合污染程度的顺序是鲫鱼团头鲂草鱼;鲫鱼和草鱼体内有机氯农药(OCPs)达到重度污染,OCPs综合污染程度为草鱼鲫鱼团头鲂; 3种鱼样重金属和OCPs复合暴露条件下健康风险评估结果表明,食用3种鱼肉的致癌风险都大于10-6,即均存在一定的潜在致癌风险,致癌风险概率为鲫鱼草鱼团头鲂,同时,食用鲫鱼还存在非致癌健康风险,其污染来源及有效防治值得进一步研究。  相似文献   

18.
加速溶剂提取-气相色谱法测定蔬菜中的有机氯农药   总被引:7,自引:1,他引:7  
加速溶剂提取技术萃取蔬菜样品中的有机氯农药残留具有萃取速度快、溶剂用量少、选择性高等优点。用加速溶剂提取-气相色谱法测定蔬菜中的有机氯农药残留,其结果与国标法(GB/T5009,19-1996)和美国EPA法(3545)进行比较。结果表明:加速溶剂提取-气相色谱法能够对蔬菜中多种有机氯农药残留的提取和测定达到很好的效果,蔬菜中12种有机氯农药在两种质量分数(25和100ng·g-1)的添加的回收率在80%和125%之间,高于国标法,而与美国EPA的方法相当。用此法对南京市郊蔬菜中有机氯农药残留状况进行分析表明:南京市郊蔬菜中有机氯农药的检出率在76%和100%之间,DDTs是蔬菜中的主要有机氯农药残留,其次为六六六,分别占残留总量的48.5%~74.6%和14.0%~27.9%。10种试验蔬菜体内DDT和六六六的残留量均不超标,但此类物质可在食物链中富集和放大,仍会对农产品质量和人体健康构成潜在威胁。  相似文献   

19.
天津市工业污染源结构分析与产业政策建议   总被引:1,自引:0,他引:1  
文章通过对天津市工业污染源结构分析,确定了天津市工业污染的重点工业行业、重点污染物排放区域以及各区域的重点排污行业,并在此基础上提出了天津市工业发展的产业政策建议。  相似文献   

20.
北江流域抗生素污染水平和来源初探   总被引:1,自引:0,他引:1  
北江是发源于湖南(武水)和江西(浈水),汇于广东韶关,流经广东全境并入海的三大河流之一。为了解整个北江抗生素污染情况,共设置44个采样点,并采集了河水及部分沉积物样品,较全面地分析了各样品中12种典型抗生素含量并初步探究了其污染来源。研究发现,包括北江源头在内的全河段均有抗生素的检出,5类抗生素在表层水和沉积物中的平均浓度分别为77.8 ng·L~(-1)和3.6 ng·g~(-1)。其中,大环内酯类污染最为严重,其含量范围为11.7~114.6 ng·L~(-1)和0~435.3 ng·g~(-1),远高于其他类抗生素。表层水中磺胺类的磺胺甲恶唑和氯霉素类的检出率达100%,其中以磺胺甲恶唑(14.7 ng·L~(-1))和阿奇霉素(25.0 ng·L~(-1))为主,而沉积物中以阿奇霉素(35.9 ng·g~(-1))、氧氟沙星(5.4 ng·g~(-1))和四环素(3.3 ng·g~(-1))为主。由于流域污染源种类和数量不同,各抗生素在北江中的分布也存在差异。表层水中抗生素含量水平表现为下游高于上中游,在沉积物中则主要集中于中、下游之间河段。这反映了人类活动强度对北江抗生素污染的直接影响。  相似文献   

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