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1.
Organic booster biocides were recently introduced as alternatives to organotin compounds in antifouling products, after restrictions imposed on the use of tributyltin (TBT) in 1987. Replacement products are generally based on copper metal oxides and organic biocides. This ban has led to an increase in alternative coating products containing the above biocides. The most commonly used biocides in antifouling paints are: Irgarol 1051, diuron, Sea-nine 211, dichlofluanid, chlorothalonil, zinc pyrithione, TCMS (2,3,3,6-tetrachloro-4-methylsulfonyl) pyridine, TCMTB [2-(thiocyanomethylthio) benzothiazole], and zineb. Since 1993, several studies have demonstrated the presence of these biocides in European coastal environment as a result of their increased use. More recently, the presence of these biocides was also revealed in waters from Japan, United States, Singapore, Australia and Bermuda. This paper reviews the currently available data on the occurrence of these biocides in the aquatic environment. Some data dealing with the environmental fate, partitioning, behaviour and risk assessment of antifouling paint booster biocides are also reported in order to discuss the detected levels of contamination.  相似文献   

2.
中国自然资源消耗与国家资源安全变化趋势   总被引:14,自引:2,他引:12  
在大量消耗自然资源与付出一定环境代价的基础上 ,中国经济得以高速增长 ,未来我国将处于世界发展格局的工业文明边缘极 ,注定将消耗更多的自然资源 ,整个社会经济体系对自然资源和环境问题更为敏感 ,我国对国际自然资源的依存度越来越强 ,其它国家的“中国威胁感”增强。鉴于上述基本趋势 ,中国未来资源安全以不出现重大资源危机为目标相对合理 ,在争取资源安全策略方面应采取的方式为 :①逐渐调整我国社会经济结构 ,使之适应自然资源短缺的现实 ,使整个经济体系资源利用效率化 ;②科学地养护我国现有自然资源基础 ,提高自然资源供给能力 ,使其免遭不可恢复的破坏 ;③全面增强各领域的国际影响力 ,积极建造有利于我国充分利用外国资源的国际秩序。  相似文献   

3.
太湖流域沉积物中有机氯农药空间分布特征及风险评价   总被引:1,自引:0,他引:1  
为了解太湖流域表层沉积物中有机氯农药的空间分布和污染特征,采集全流域111个表层沉积物样品,用GC-μECD分析了20种有机氯农药的含量,并基于沉积物质量基准法对沉积物污染风险进行评价。结果表明:太湖流域沉积物中20种有机氯农药(OCPs)的总含量介于16. 3~96. 9 ng/g dw之间,平均值为35. 0ng/g dw,其中HCHs和DDTs是主要的检出成分,平均含量分别为12. 1、7. 6 ng/g dw,两者含量之和占总OCPs的25. 5%~85. 5%。特征化合物指数法分析结果表明,HCHs主要来源于林丹,而且该区域仍然有新的DDT输入,并且大部分p,p’-DDT通过好氧生物降解为p,p’-DDE。沉积物质量基准法评价结果显示,γ-HCH、DDTs潜在生物毒性较大。  相似文献   

4.
Imposex, i.e., the imposition of male sexual characteristics on female neograstropods, has been used worldwide as a bioindicator of pollution by the antifouling agent TBT as well as to assess the related ecological impact. The recent total ban on the use of TBT in the maritime industry has been partly based on the use of such a biomarker. This is mainly based on the assumption that no other pollutant, or environmental stress, is able to induce such a biological response. Nonetheless, several authors had challenged this idea. The present paper will present further field observations on imposex in Hexaplex trunculus from Malta (Central Mediterranean) which may help clarify this issue. Furthermore, the incidence of imposex in this species will be related to body burdens and to the environmental levels of organotins as measured analytically. First histological observations will also be presented which may help clarify the ecological significance of this response in this species. Finally a number of alternative scenarios regarding the relationship between imposex and TBT will be discussed.  相似文献   

5.
In today’s competitive market, corporations have learned that taking sustainability issues into account can significantly improve their public image. Modern producers therefore must simultaneously reduce the environmental impact of their products and make economic gains. Therefore, making trade-offs between economic and environmental issues is required to ensure a company’s continuity. In doing so, companies have attached a great deal of importance to the new product design phase. However, optimization at the design stage becomes very complex for a product with a large number of parts, which can have several design alternatives with similar forms and functionality, but different costs and environmental impacts. In the automobile, shipbuilding and aircraft industries, if the conventional complete enumeration method is applied, the time required for selecting the optimal combination of design alternatives with respect to life cycle cost and environmental impact may exceed a human’s natural life span. To overcome this limitation, this paper introduces an optimization method for use as a design aid tool that enables a designer to assess the life cycle cost and environmental impact of his/her design very early in the product development process. To support the developed method, an illustration is provided using a case study on a locally manufactured automobile.  相似文献   

6.
Detailed analyses of persistent organic pollutants (POPs) such as hexachlorocyclohexane (HCH) isomers (HCHs), dichlorodiphenyltrichloro ethane (DDT) and its metabolites (DDTs), hexachlorobenzene (HCB) and congeners of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in surface sediments from the coastal estuarine environment of West Bengal, northeast India allowed the evaluation of the contamination status, distribution and possible pollution sources. HCH, DDT, HCB, PCB and PAH were identified compounds in all the samples, whereas the concentrations of chlorinated pesticides (trans-eptachlorepoxide, dieldrin, endrin, metaoxychlor and mirex) were below the detection limits and were not of great concern. The pesticides did demonstrate markedly different distributions reflecting different agricultural and domestic usage in the region. The range of concentrations of HCH, HCB, DDT and PCBs in the sediments were 0.11-0.40, <0.05-0.98, 0.18-1.93 and 0.18-2.33 ng/g dry wt, respectively. Overall elevated levels of HCB, DDT and PCB were recorded at Babughat, a very closely located site of the metropolitan megacity Calcutta. Fluoranthene (flu) and pyrene (py), the dominant 4-ring PAHs, also showed an abrupt elevated concentrations at Babughat with values of 214 and 144 ng/g dry wt, respectively. Among the isomers and metabolites of HCH, DDT and PCB, alpha-HCH, pp'-DDT and PCB (101), PCB (118), PCB(153) and PCB (138) were found to be dominant. High ratios of metabolites of DDT to SigmaDDTs reveal recent use of DDT in this coastal environment. Fluoranthene, pyrene, 1,2-benzo(a)anthracene and chrysene formed the dominant congeners out of 19 identified PAHs. The sources of contamination are closely related to human activities such as domestic and industrial discharge, automobile exhausts, street runoff, slum sewage, agricultural chemicals and soil erosion due to deforestation as well as atmospheric transport. This study is compared to other coastal and estuarine environments in India and abroad. The baseline data can be used for regular ecological monitoring, considering the industrial and agricultural growth around this important estuarine ecosystem.  相似文献   

7.
城市是一个开放的、复杂的巨系统,洪涝灾害对该系统中的自然、基础设施、社会经济等要素产生直接或间接影响,理清洪涝灾害与城市系统的交互关系,并评估预测其应对洪涝灾害的韧性能力,有助于韧性城市的规划建设。通过分析洪涝灾害与城市系统要素间的反馈关系,构建了城市洪涝韧性仿真模型,并以南京市为例,设定了现状延续型、经济优先型、规划发展型、韧性发展型4种发展情景,模拟在4种情景下2009~2025年南京市洪涝韧性的动态变化。结果表明:(1)构建的城市洪涝韧性仿真模型能够反映洪涝灾害与城市系统要素间的交互关系,用于预测城市洪涝韧性变化;(2)城市系统中建成区绿化覆盖面积、雨水管网设计标准对城市洪涝韧性影响显著;(3)根据现有城市发展规划,南京市洪涝韧性将不断提升,且优于现状延续发展情景,但与世界典型韧性城市还有一定差距,建议南京市从城市绿化、雨水管网设计标准、经济结构、人口素质等方面提升其洪涝韧性能力。研究结果可为南京市及其它城市韧性城市发展规划制定提供理论与科学依据。  相似文献   

8.
农业面源是造成太湖富营养化的重要污染源。通过对太湖西岸重点保护区内农民进行随机入户调查,系统地研究了当地农民在水稻种植中的施肥行为特征及其主要影响因素。研究结果表明:(1)在普遍过度施用氮肥的背景下,个体农户在施肥量和施肥种类上存在显著差异;(2)农户施肥行为普遍具有主观性和盲目性的特征。农民的年龄阶段和其对控制化肥用量的态度对氮肥施用量具有显著性影响;(3)在分析化肥施用态度和环境意识对施肥量的影响中,出现了一些与预期相反的趋势。这进一步显示了当地农民在施肥方面缺乏科学引导,导致部分农民尽管存在着良好的控制化肥施用的意愿,却不知如何有效实施。因此,针对当地农民年龄大、文化低等普遍特征,有针对性地设计一些不用复杂模型和流程的简单施肥改善项目,并辅以参与激励措施与风险保障措施,在降低当地氮肥施用量和流失量方面具有巨大潜力,并对太湖流域的水污染控制起到事半功倍的效果  相似文献   

9.
作为实现乡村振兴战略的重要抓手,如何实现农药零增长一直是现代农业政策关注的重点。基于上述问题,通过全国18个省份农户的微观调查数据,尝试从精细管理技术投入的视角,分析劳动成本变化对农户农药使用行为的影响。研究发现:对于从事园艺等劳动密集型作物种植的农户而言,劳动成本上升将促使农药施用量的增加,而精细管理技术投入则在两者间起到部分中介作用。精细管理技术投入的增加能够有效提高农户的施药效率并降低其单次的农药用量。而与此同时,由于精细管理农户所面临的经营风险相对较大,因而农药施用次数相对较高,故不同精细管理技术投入的农户在农药施用总量方面并未呈现明显差异。因此,政府可尝试通过扶持农产品品牌建设、发展农业生产服务组织等方式,在引导农户生产方式精细化的同时,实现农药的减量投入。  相似文献   

10.
基于中国陆地生态系统服务功能价值研究成果,以及重庆市万州区生态环境建设与经济社会发展水平,对不同土地利用类型单位面积生态服务价值进行修正,形成万州区土地利用结构优化灰色线性规划模型中决策变量的生态经济参数。计算结果表明:(1)规划期内万州区耕地面积略有减少,建设用地面积有所增加,林地面积有较大幅度增加,大规模增加湿地面积提高土地生态功能价值则难以实现;(2)地质灾害与水土流失综合治理、草地生态系统修复以及适当增加园地面积,能够提高万州区土地生态功能价值;(3)万州区土地生态经济理论价值为11888亿元/a,修正价值为10644亿元/a,均高于现状值9653亿元/a,土地生态修复与建设的生态经济效益可观;(4)基于生态系统服务价值的土地利用结构优化,能够满足社会经济发展对土地的需求并同步实现生态经济效益的最优,为解决土地利用规划中的关键技术问题提供新的方法。  相似文献   

11.
基于SD模型的三峡库区快速城镇化地区耕地利用模拟研究   总被引:4,自引:0,他引:4  
对引起耕地变化的驱动因素进行研究,有利于解决当下人口、经济和社会发展与耕地资源的矛盾。基于对耕地变化相关因素的线性分析,提出改进基于时间序列对耕地变化驱动力静态研究的模式,利用系统动力学模型从动态的耕地变化仿真模拟过程中对长寿区耕地变化趋势进行预测研究,为快速城镇化地区耕地资源的合理利用与保护提供借鉴。结果表明:(1)长寿区耕地面积25 a间共减少 9 535 hm2,在数量上总体呈现波动下降趋势;(2)长寿区耕地变化的主要驱动力与社会经济发展、人口与城市发展、农业结构调整与科技进步密切相关;(3)利用SD模型在不同情景设定下的模拟发现,区内城镇化率对耕地面积的影响>GDP对耕地面积的影响>人口增长对耕地面积的影响;(4)耕地利用变化在不同社会经济发展模式下的差异较大,而GDP和城镇化率的缓速增长发展模式最为理想,对区内耕地资源保护有一定的促进作用。由此可以得出,为减轻未来长寿区耕地保护工作压力,必须转变以牺牲耕地作为代价的经济发展模式,通过集约节约用地、积极开展农村建设用地复垦等工作来协调城镇化的快速发展与耕地保护之间的矛盾。 关键词: 耕地变化;驱动力;耕地非农化;系统动力学;城镇化;三峡库区  相似文献   

12.
南水北调中线工程是解决中国北方缺水问题的一项战略性措施,将对湖北省土地资源开发利用产生深远影响。该工程所淹没土地利用强度大,利用效率高,故淹没损失大;移民开发、工矿及公共基础设施搬迁用地大,移民开发将受到资金和生态环境的制约;补偿工程所占用耕地将对湖北省耕地占补平衡造成很大的压力,严重影响汉江中下游生态环境及土地利用效益。工程开工对湖北省土地开发利用是弊大于利。建议移民安置以外迁安置为主,后靠安置为辅,结合库区农业产业化的发展,实行开发性移民政策,移民搬迁用房和各项专业设施复建尽量少占耕地;库区土地开发应以提高现有耕地质量为主,以开垦荒山荒坡为辅,考虑从中线工程收益中拿出资金用于改善库区生态环境,并补偿汉江中下游因调水而遭受的农业、航运及环境质量的损失。为了尽量保护农业用地的生产能力,引江济汉工程沿线的农田水利系统恢复功能应同步设计,同步施工。  相似文献   

13.
The development of bacteria resistant to antibiotics is viewed as a medical health threat. Because thousands of people die every year due to antibiotic-resistant bacteria, efforts are underway to reduce antibiotic usage which in turn will reduce the development of antibiotic-resistant bacteria. In the United States, the use of antibiotics in the production of food animals to enhance animal growth has been identified as contributing to resistance. In 2015, a veterinary feed directive was adopted by the U.S. federal government prohibiting nontherapeutic uses of antibiotics in food animals that should reduce usage. The continued usage of antibiotics by producers for preventing disease may mean the directive is insufficient to reduce nontherapeutic antibiotic administration. This may lead some consumers to seek meat products from animals raised without antibiotics. A governmentally-sponsored labeling program could encourage reduction in antibiotic usage.  相似文献   

14.
满足生态安全的土地利用结构优化是协调社会经济发展与生态环境间矛盾、实现土地持续利用的有效途径。以武汉城市圈为研究区,基于2002~2009年土地利用变更调查汇总数据,引入土壤有机碳储量和土地利用绿当量两个生态指标,评价了城市圈发展不同阶段土地利用结构的生态效益;并通过TOPSIS模型对历年土地利用结构生态合理度进行了评价。在此基础上,以经济效益和生态效益的最大化为目标,构建了2020年多目标优化模型,获得了符合城市圈发展需求的土地利用结构优化方案,呈现“四增三减三稳定”的数量格局,且生态效益指标和生态合理度均呈正向的发展趋势;进而提出了土地资源可持续利用的建议。研究结果对武汉城市圈土地利用总体规划修编、土地利用调控方案的优化以及土地可持续利用具有重要指导意义  相似文献   

15.
基于熵权TOPSIS模型的土地利用多功能性诊断   总被引:1,自引:0,他引:1  
从经济、社会和生态3个方面出发构建土地利用多功能性评价指标体系,应用熵权TOPSIS模型对江苏省近年来土地利用多功能性进行诊断分析可以优化区域土地的合理开发,提高土地利用效率,为促进区域的可持续发展提供有效依据。研究结果表明:2006~2016年江苏省土地利用综合功能经历了一般—良好的发展阶段,综合功能在不断优化;经济功能经历了较差—一般—良好—优秀—良好的发展阶段,虽然有所波动,但其依旧呈增长态势;社会功能经历了较差—一般—良好—优秀的发展阶段,呈现出持续稳步提高趋势;生态功能经历了一般—良好—一般的发展趋势,整体呈下降趋势。另外土地利用的经济功能和社会功能子目标的障碍度在逐年下降,对目前江苏省土地利用有效性起制约作用的主要是生态功能,应减少废水排放和工业固体废弃物等污染造成的生态破坏,加强水资源的保护,同时缩小城乡差距,推进城乡融合,促进土地利用过程中经济、社会和生态功能的协调发展。  相似文献   

16.
Organochlorine pesticides (OCPs) are an important potential component of chemical pollutants used extensively for agriculture and sanitation purposes in India as these are comparatively cheap and effective. These persistent organic compounds such as HCH isomers, DDT and its metabolites are the predominant chemical contaminants found along the Indian coast and thus constitute both alluring and grave areas of scientific research. Our objective in the paper is to provide a comprehensive account of the distribution of organochlorine pesticides in biotic and abiotic compartments of the Indian coastal environment, make some comments on their environmental sources, their movement through the food chain and possible ecotoxicological risk of health in biota including humans. The prevalent HCH, DDT and HCB concentrations differ markedly in eastern and western coast of India reflecting differing agricultural and other usage and their ultimate input into the coastal environment by several rivers and the bioturbation activities of macrozoobenthos (bivalve mollusks, polychaetous annelids, etc.). In several cases, the DDT levels exceeded the effects range-low (ER-L) and could thus cause acute biological impairments, in comparison with the sediment quality guidelines. Contributions of DDT metabolites (DDT, DDD and DDE residues) vary in different Indian coastal regions predominated by pp'-DDT and pp'-DDD. Measured concentrations of HCHs were lower than DDTs that might be due to higher water solubility, vapor pressure and biodegradability of the latter. HCH and DDT residues in fish in India were lower than those in the temperate countries indicating a lower accumulation in tropical fish, which might be related to rapid volatilization of this insecticide in the tropical environment. The concentrations of other chlorinated pesticides (aldrin, dieldrin, eldrin, methoxychlor, endosulfan sulphate) were lower and not generally of great concern.  相似文献   

17.
Climate change will impact on ecological, social, and economic elements of fisheries; however, the three are seldom considered in an integrated fashion. We develop a fishery-level assessment of economic resilience to climate change for the Tasmanian rock lobster fishery, a linked social–ecological system. We outline the main climate change forcing influences that link climate change to the fishery via changes in lobster abundance, distribution, and phenology. Using a bottom-up approach, we identify twelve economic attributes strongly related to the fisheries’ economic resilience to climate change. Resilience attributes are grouped according to the level of the economic domain (business, sectoral, and governance). Attributes are then evaluated to determine the overall economic resilience of the rock lobster fishery in the context of the specific nature of predicted climate change effects. We identify areas of low resilience in the economic sub-system for this fishery. Evaluating the economic resilience of regional fisheries using this integrated, interdisciplinary framework provides a practical, parsimonious, and conceptually sound basis for undertaking comprehensive and contextually tailored assessments of climate change impacts and economic vulnerability. The framework can be extended to include a broader range of climate change impacts and the social domain of the human sub-system.  相似文献   

18.
八步里沟位于大渡河上游,沟口堆积扇为金川县城,历史上泥石流灾害严重。20世纪80年代以来,对泥石流灾害进行了综合治理,工程防治效果明显,通过近30a的演化,防治工程与泥石流灾害共同作用形成了独特的泥沙资源并进行了初步开发。分析了八步里沟的资源特征、综合开发利用的制约因素、开发与保护的优化配置以及进一步开发的空间等问题,发现拦砂坝库区的建材开发有效延长了工程运行年限,沟内种植经济林抑制了泥石流灾害,拦砂坝抬高沟床侵蚀基准面为小水电开发和灌溉提供了水头,经济发展与灾害防治形成良性循环,达到可持续发展的目的。为提高资源利用率,最大化发挥防灾工程的经济效益和社会效益,可进一步利用现有治理工程建立泥石流防治的科普基地,沟口堆积扇泥石流排导工程两侧设立限制开发区、建立生态公园,达到优化资源开发的目的。  相似文献   

19.
The degradation of DDT in aqueous phase was studied by treating it with microflora present in activated sludge developed in bench-scale reactors and in vitro by incubating it with mixed liquor from the activated sludge and with the bacteria obtained after enrichment of the mixed liquor culture through repeated transfers with increasing doses of DDT in standard inorganic medium. It was observed that several strains of bacterial isolates as well as the mixed culture were able to degrade DDT with hardly any formation of the stable metabolites DDD or DDE. The activated sludge degraded DDT (1 to 55 mg/L) almost completely within 23 h, as only some of the effluent samples contained DDTs up to 0.03 mg/L. The bacteria belonged to the genera Bacillus, Micrococcus, Pseudomonas, and Flavobacterium. The mixed liquor and individual bacteria, when incubated with DDT in a mineral medium for 42 days under culture conditions which were static, brought about 50% to 74% and 44% to 69% degradation of DDT respectively. Under shaked conditions, these bacteria, when incubated up to 1 month with 50,200 and 500 mg/L DDT, showed 5.3% to 76.6% degradation of DDT, respectively. Traces of DDE and DDD were detected in a few samples. The microorganisms were able to utilise DDT as a source of carbon and hence can be used for biotreatment of DDT.  相似文献   

20.
北京城市人口的增长是必然的 ,但必须对人口规模进行必要的调控 ,这是北京实现可持续发展的需要。北京城市人口增长调控要运用市场化的方式 ,辅之以必要的行政措施 ,以结构调整为导向 ,适度控制城市人口数量的增长 ,重点优化城市人口结构 ,合理调整城市人口空间布局  相似文献   

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