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2003年5月、8月和10月对东山湾巴非蛤养殖区环境状况进行调查,根据调查资料,分析了巴非蛤养殖区海水、表层沉积物中Cu、Pb、Cd、Zn的含量分布,并进行生态环境质量评价及潜在生态危害评价.结果表明:东山湾巴非蛤养殖区海水中Cu、Pb、Cd、Zn的平均含量分别为1.75 μg.L-1,1.69 μg.L-1,0.02 μg.L-1,2.84 μg.L-1,其季节变化从高到低依次为10月>8月>5月;沉积物中Cu、Pb、Cd、Zn的平均含量分别为14.0 mg.kg-1、34.8 mg.kg-1、0.031 mg.kg-1、97.5 mg.kg-1.生态质量评价结果表明,养殖区海水重金属的含量符合第二类海水水质标准要求,处于清洁水平.养殖区沉积物重金属的含量符合第一类海洋沉积物质量标准,属于较清洁水平.生态危害评价表明,Pb和Cd的潜在生态危害系数大于Cu和Zn,但整个养殖区沉积物中重金属的潜在危害属于轻微,养殖环境良好.  相似文献
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微山湖内源有机氯农药残留的生态风险评估   总被引:2,自引:0,他引:2       下载免费PDF全文
微山湖作为南水北调东线工程的重要缓冲枢纽,其内源水质对南水北调东线工程影响至关重要。为了研究微山湖水体和沉积物中有机氯农药污染的潜在风险,从微山湖30个采样点采集湖区上覆水体和表层沉积物样品,采用气相色谱法对其中的有机氯农药含量进行测定。结果表明,①微山湖水体中HCHs和DDTs的含量分别为34.4-195.9ng/L和34.9-168.5ng/L,与国内外其他地区湖泊相比污染水平偏高,但均未超出我国地表水环境质量标准;沉积物中HCHs和DDTs的含量分别为4.52-7.50ng/g和4.73-7.67ng/g,总体而言,相对国外其他地区湖泊污染水平偏高,相对国内其他地区湖泊污染水平偏低。②微山湖水体有机氯农药的非致癌风险总体处于低水平,致癌风险仍然存在,但随着采样时间的推移,水体中有机氯农药的非致癌风险和致癌风险均呈现递减趋势。③微山湖沉积物中有机氯农药的非致癌风险指数与致癌风险指数均小于风险警戒值,但90%的采样点沉积物中DDE和全部采样点沉积物中DDT的残留量介于ERL和ERM之间,会对生物产生毒性作用。  相似文献
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Ecosystem-based management (EBM), in the context of fishing, considers impacts on all parts of an exploited marine ecosystem. Understanding the impacts of fishing on habitats is a necessary part of adopting EBM, but multi-scale data that describe the types and distributions of habitats, and the interactions of fishing with them, are typically limited or entirely lacking. An approach developed to address habitat impacts, and applied to all offshore bottom contact fisheries in Australian waters, forms part of a hierarchical risk assessment framework - the Ecological Risk Assessment for the Effects of Fishing (ERAEF). Its progressively quantitative hierarchical approach enables higher-risk interactions to be identified and prioritised in the early and intermediate assessment stages by screening out lower-risk interactions. The approach makes the best use of all available data, but it can also be inferential where data are lacking. At the intermediate level of the ERAEF, a semi-quantitative approach uses a general conceptual model of how fishing impacts on ecological systems, with a focus at the level of regional sub-fisheries defined by fishing method (gear type). A set of quantifiable attributes for habitats are used to describe the ‘susceptibility’ of each habitat to damage that may be caused by specific fishing gears; resilience is generalised as a habitat's inherent ‘productivity’ (ability to recover from damage). In the ERAEF, photographic imagery was used effectively to provide a standardised method to classify habitats, to visualise the attributes assessed, and to communicate with stakeholders. The application of the ERAEF to habitats is illustrated using results from a multi-sector fishery off southern Australia that has five primary sub-fisheries: two bottom trawl (‘otter trawler’ or ‘dragger’), bottom set auto-longline, bottom set gill net, and Danish seine. In the case of the otter trawl sub-fishery, a set of 158 habitat types was considered, of which 46, mostly on the outer continental shelf and slope, were identified as potentially higher risk and deserving management attention. Strengths of the ERAEF approach for benthic habitats include methodological flexibility and wide applicability, and in being interactive and inclusive - bringing stakeholders, scientists and managers together to ‘put habitat on the radar’ and to develop management solutions. Limitations include difficulties in construction and validation of scored attributes and scale dependence. In the context of ecological risk management, this method offers a way to assess risks to marine habitats in a rigorous, transparent, and repeatable manner.  相似文献
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根据2005年4月和10月厦门贝类养殖区环境调查资料,着重对贝类养殖区表层沉积物中重金属的含量水平进行分析,并对贝类养殖区的表层沉积物进行质量评价及潜在生态危害评价.结果表明:厦门贝类养殖区沉积物中Cu、Pb、Cd、Zn、Hg、As的平均含量分别为20.0mg.kg-1,39.5mg.kg-1,0.07mg.kg-1,97.3mg.kg-1,0.05mg.kg-1,7.20mg.kg-1.其中同安湾北部和湾顶养殖区及西海域的杏林、东山养殖区,6种元素的含量均较高;位于同安湾的刘五店、澳头养殖区,含量均较低.沉积物质量评价结果表明,贝类养殖区沉积物中重金属的含量符合第一类海洋沉积物质量标准,属于较清洁水平.Hg、As和Cd的潜在生态危害系数大于Cu、Pb、Zn,整个养殖区沉积物中重金属为轻微生态危害,养殖环境良好.  相似文献
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祁剑飞  曾志南  宁岳  巫旗生 《水产学报》2016,40(7):1099-1105
为了评价底栖动物增殖放流过程中存在的生态风险,通过现场调查、已有文献资料分析和专家咨询,建立了以层次分析法为基础的生态风险评价体系.应用该体系对5种增殖放流的底栖动物进行了生态风险评价.研究表明,西施舌、紫海胆、韩国文蛤和泥东风螺为“中”风险等级;波纹巴非蛤为“低”风险等级.本研究可为今后增殖放流过程中的生态风险评价提供参考.  相似文献
6.
In this study, an integrative weight of evidence (WOE) tetrad methodology was developed and used to assess environmental quality and ecological risk at contaminated sites by fish farm effluents using spatial modelling tools [geographical information systems (GIS) and fuzzy logic and multicriteria analysis (MCA)], taking into account the results of four lines of evidence (LOE): the physico‐chemical characteristics of water and sediment, acute toxicity bioassays, biomarkers and the in situ alteration of benthic communities. The methodology was tested in the Rio San Pedro salt marsh creek in southwestern Spain. The proposed approach allowed for a quantitative spatial characterization of ecological risk and a better discrimination based on various types of physical, chemical and biological data. The methodology illustrates how GIS spatial models may be used in conjunction with other tools such as fuzzy logic and MCA to assist in decision‐making processes based on multiple environmental quality criteria and lines of evidence, with the transparency, objectivity and synoptic ability required to address environmental management problems in general and the management of contaminated marine areas affected by fish farms in particular.  相似文献
7.
浙江温州地区经济发达,涉及重金属的行业较多,其中Cu、Pb、Zn、Cd、Cr、As 6种重金属污染潜在风险较大。为了解该区域重金属经河流对近岸海域造成污染的基本状况,开展温州区域三条主要入海河流瓯江、飞云江和鳌江水体中6种重金属的空间分布特征研究,并采用重金属污染指数法(HPI)和物种敏感性分布法(SSD)进行生态风险分析。结果表明Cu、Pb、Zn、Cd、Cr、As的浓度分别在12.46-1830.01 μg/L、2.94-372.79 μg/L、19.58-435.04 μg/L、0.06-0.79 μg/L、14.11-192.98 μg/L和1.59-63.95 μg/L之间,平均值分别为801.68 μg/L、73.80 μg/L、168.61 μg/L、0.26 μg/L、81.06 μg/L和23.53 μg/L。HPI评估结果表明:O4、F2、A1和A2四个站位重金属污染程度高,F1站位污染程度中等,O1、O2、O3和A3污染程度低;其中对水体重金属污染贡献程度高的四种重金属分别为Cu、Pb、Cd和Cr。SSD风险评价结果表明:Cu、Zn、Cr和As在所有站位的表现均为高生态风险,说明这四种重金属对生物存在极高的潜在危害性;Pb在O4和A2站位表现为高生态风险。通过对两种方法的比较发现两种方法从不同角度对重金属的潜在生态风险进行评价,能有效的规避单一评价方法的不足,互为补充:首先选取HPI评价法确定高污染程度的区域,再通过SSD生态风险评价方法筛选该区域生态毒性高的重金属,进行重点高效的监测和预防。  相似文献
8.
以贵州锁黄仓湿地表层沉积物为研究对象,分析沉积物中Cr、Ni、Zn、As、Pb等5种重金属元素含量空间分布特征,并进行生态风险评价。结果表明:Cr、Ni、Zn、As、Pb的平均值分别为98.44、73.14、148.67、21.93、54.32 mg/kg。与土壤重金属背景值相比较,5种重金属含量均偏高,而各重金属变异系数相对较小(13.94 %~21.55 %)。Cr、Ni、As间呈极显著正相关(P<0.01),Zn与Pb间呈极显著正相关(P<0.01)。主成分分析中A1(第一主成分)包括Cr、Ni和As,A2(第二主成分)包括Zn和Pb。锁黄仓表层沉积物重金属污染负荷指数为1.348,且上游>下游>中游,均属于“中等”污染程度。潜在生态风险评价表明,5种重金属潜在生态风险指数小于下限(RI=150),属于轻度生态污染。Cr、Ni和As的来源途径可能相同,主要受周边农业活动和环境影响;Zn和Pb具有相同输入源可能性较大,主要受炼锌业和交通运输影响。综上,锁黄仓湿地受到中等程度的污染,但生态环境质量属于可控范围。  相似文献
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