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外来水生生物入侵被认为是导致我国水生生态系统生物多样性破坏的主要因素之一,同时阻碍了我国水产养殖业的健康发展。在众多造成水生生物入侵的因素中,外来水产动物的引进是重要因素之一,其中不仅包括外来物种自身造成的生物入侵,也包括外来物种携带的病原生物对本土物种、生态环境、人类健康等造成的巨大威胁。为了对待引入外来水产动物的风险进行科学评估,根据分析常见外来水生动物可能存在的入侵机制与生态风险,利用层次分析法和成对比较矩阵方法对指标权重进行计算,构建了外来水产动物引进的风险定量评估体系。该评估体系包括6个一级指标(即外来种自身性质、外来种生态风险、病原生物入境、病原生物暴露、危害与影响、外来种风险防控)和32个二级指标。利用该评估体系对我国境内现有的三种外来水产动物进行定量的风险评估,评估结果显示:鳄雀鳝(Atractosteus spatula)的风险值R为3.5975,为高风险等级;虾夷扇贝(Mizuhopecten yessoensis)风险值R为2.7823,为中风险等级;锦绣龙虾(Panulirus ornatus)风险值R为1.9568,为低风险等级。该评估结果与我国农业农村部、生态环境部、海关总署等相关单位提供的资料高度吻合,说明该模型在外来水产动物引进与养殖风险评估的相关工作中有重要的应用价值。 相似文献
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<正>生物入侵是指某种生物从外地自然传入或人为引种后成为野生状态,并对本地生态系统造成一定危害的现象。这些生物被叫做外来物种,是指那些出现在其过去或现在的自然分布范围及扩散潜力以外(即在其自然分布范围以外或在没有直接或间接引 相似文献
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近年来,外来物种入侵已引起人们的忧虑与重视。本文就水生“外来物种”入侵温州水域的现状进行调研,并提出对策。 相似文献
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2月17日,专家对广东海洋大学完成的“粤两淡水及河口区鱼类多样性调查及保护利用”科技成果进行鉴定。记者从会上获悉,漠阳江外来物种入侵现象比较严重。 相似文献
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在淡水鱼类资源调查和外来物种采样监测中,广东江河发现的外来物种主要是罗非鱼、巴西龟、革胡子鲶、下口鲶(清道夫)等,几乎所有较大江河里都发现了它们的踪影,尤其是罗非鱼大量入侵自然生态体系。据渔民反映,在鉴江、袂花江捕捞渔获中罗非鱼占了总数的60%左右,在漠阳江所占的比例甚至更高。 相似文献
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<正>外来生物入侵已引起了公众和媒体的广泛关注,成为一个全球性的重要问题。按照世界自然保护同盟IUCN的定义,所谓外来入侵物种(Invasion alien species,IAS)是指从自然分布区通过有意或无意的人类活动而被引入,在当地的自然或半自然生态系统中形成了自我再生能力,并给当地的 相似文献
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为对引入我国的外来水产动物的风险进行定量地科学评估,促进我国水产养殖业健康可持续发展,本研究通过分析外来水产动物的生物性质、入侵机制和可能带来的生态风险,以及外来水产动物传带疫情疫病的风险,并结合风险可能存在的危害与影响和风险防控管理办法等因素确定风险评估的指标。利用层次分析法 (analytical hierarchy process,AHP)和成对比较矩阵方法对各指标的权重进行计算,构建了一个外来水产动物引进的风险定量评估体系。该评估体系包括6个一级指标 (外来种生物学性质、外来种生态风险、病原生物入境、病原生物暴露、危害与影响、外来种风险防控)和30个二级指标。利用该评估体系对我国境内现有的3种外来水产动物进行定量地风险评估,评估结果显示,鳄雀鳝的风险值
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本研究通过调查、分析草鱼出血病发生的各种风险因素,初步构建该病发生的风险评估模型,旨在为防控疾病提供决策依据。该模型包括由层次分析法构建的指标体系,以德菲尔法确定的各风险因素权重,由综合评价法表述的风险评估结果。构建的草鱼出血病风险指标体系包括9个目标层,即鱼种(B1)、免疫(B2)、水质(B3)、放养密度(B4)、水温(B5)、饲养管理(B6)、发病史(B7)、天气(B8)、池塘状况(B9);26个风险指标层,主要包括如鱼种是否带毒(C1)、是否免疫(C4)、免疫时健康状况(C6)、放养密度(C13)、水温(C14)、近年来发病情况(C19)等。目标层风险因素权重值集合为W={0.167;0.202;0.124;0.109;0.101;0.097;0.092;0.081;0.064},其中免疫和鱼种权重值最高。采用综合评价法表示风险评估结果,其函数模型为,ij ij得出华中地区、西南地区和华南地区发生草鱼出血病的风险值分别是0.699、0.690、0.568,与实际调查结果相符,即采取免疫接种措施后华南地区发生草鱼出血病的风险较华中和西南地区低。 相似文献
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海洋生物体多环芳烃污染残留及其健康风险评价研究 总被引:1,自引:0,他引:1
多环芳烃(PAHs)主要来源于煤、石油等矿物燃料及其他有机物的不完全燃烧和裂解过程,是一类广泛存在于环境中具有潜在致畸、致癌和致突变效应的持久性有机污染物。PAHs引起的污染问题越来越受到人们的关注,已经被世界许多国家列为有机污染物的研究重点。海洋环境中的PAHs可以通过生物积累和食物链传递作用进入鱼类、贝类等海洋生物体中,不仅影响海洋生物的生存繁衍,破坏海洋生态环境,还会通过水产品影响人类健康。文章重点对近年来国内外鱼类、贝类等海洋生物体PAHs残留分析方法、残留水平的影响因素、来源解析以及人体暴露健康风险评价等方面进行了综述,同时指出了目前研究还存在的一些问题,为今后的研究提供了疗向。 相似文献
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湛江红树林海域生物体中多环芳烃污染水平及其健康风险评价 总被引:3,自引:1,他引:2
对湛江红树林海域24种海洋生物体内多环芳烃(PAHs)的含量水平、组成及食用安全性进行了研究。结果表明,鱼类、头足类、甲壳类和贝类生物体PAHs总量范围分别为191~548 ng/g(干重,下同)、348~460 ng/g、337~518 ng/g和380~491 ng/g,平均含量分别为349.2 ng/g、420.9 ng/g、424.3 ng/g、455.9 ng/g。各类生物体中PAHs含量存在一定的差异,平均含量由高到低依次为:贝类、甲壳类、头足类、鱼类。与国内外相比,湛江红树林生物体PAHs含量处于中等偏下水平。组成分析与风险评价结果显示,湛江红树林海域鱼类、头足类、甲壳类和贝类生物体中主要以3环PAHs为主,苯并芘(Ba P)含量处于欧盟规定的限值范围,PAHs致癌风险尚处于可接受致癌风险水平(10–5)。 相似文献
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- 1. Several species of marine mammals are at risk of extinction from being captured as bycatch in commercial fisheries. Various approaches have been developed and implemented to address this bycatch problem, including devices and gear changes, time and area closures and fisheries moratoria. Most of these solutions are difficult to implement effectively, especially for artisanal fisheries in developing countries and remote regions.
- 2. Re‐zoning of the Great Barrier Reef World Heritage Area (GBRWHA) in 2004 closed 33% of the region to extractive activities, including commercial fishing. However, the impact of re‐zoning and the associated industry restructuring on a threatened marine mammal, the dugong (Dugong dugon), is difficult to quantify. Accurate information on dugong bycatch in commercial nets is unavailable because of the large geographic extent of the GBRWHA, the remoteness of the region adjacent to the Cape York Peninsula where most dugongs occur and the artisanal nature of the fishery.
- 3. In the face of this uncertainty, a spatial risk‐assessment approach was used to evaluate the re‐zoning and associated industry restructuring for their ability to reduce the risk of dugong bycatch from commercial fisheries netting.
- 4. The new zoning arrangements appreciably reduced the risk of dugong bycatch by reducing the total area where commercial netting is permitted. Netting is currently not permitted in 67% of dugong habitats of high conservation value, a 56% improvement over the former arrangements. Re‐zoning and industry restructuring also contributed to a 22% decline in the spatial extent of conducted netting.
- 5. Spatial risk assessment approaches that evaluate the risk of mobile marine mammals from bycatch are applicable to other situations where there is limited information on the location and intensity of bycatch, including remote regions and developing countries where resources are limited.
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Predicting invasion risk involves inherent uncertainty when data on biological and ecological characteristics are lacking. To combat data gaps, assessors are required to use information from secondary sources, further reducing predictive accuracy. Lionfish in the subfamily Pteroinae have invasion history in the Western Atlantic Ocean and Mediterranean Sea, raising concern that other species of globally traded lionfish may pose risks similar to the invasive complex comprised of the red lionfish (Pterois volitans, Scorpaenidae) and devil firefish (Pterois miles, Scorpaenidae). We conducted a standardized literature review of 18 species in the genera Pterois, Dendrochirus, and Parapterois to (a) characterize the volume and composition of literature addressing the invasive complex pre‐establishment and pre‐spread, and compare it to the body of literature that has been generated post‐spread and impact, (b) compare the volume and composition of literature addressing other members of Pteroinae to the invasive complex, and (c) evaluate data quality addressing the Pteroinae by characterizing literature used to generate biological profile reports during a risk screening protocol. Little data were available for the invasive complex prior to introduction and focused primarily on the composition or effects of venom. Following introduction, there was a considerable time lag in research effort. Post‐spread, research effort increased rapidly. We identify similar data deficiencies for other species of lionfish that have not been reported outside of their native ranges. While proactive management is gaining support as an effective framework, it is important to understand data limitations and their resulting uncertainties, which leads to more informed proactive management. 相似文献