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91.
基于物种敏感性分布法的毒死蜱对稻田生态系统生态风险评价 总被引:2,自引:0,他引:2
生物敏感性分布法(Species Sensitivity Distributions,SSD)是一种基于单物种测试和概率统计学的、较高级的外推风险评估方法。该方法在国内外均被广泛应用于各种污染物风险评价中。本文选取了采用logistic和normal这2种SSD分布模型,分析了国内外毒死蜱对3组水生生物组合的毒性数据;并且获得各自SSD的HCx值。3组毒性数据分别为:浙江稻田水生生物组,长三角地区水生生物组和美国水生生物组。浙江稻田水生物SSD分布的HC5为:0.32μg·L~(-1)(logistic模型)和0.35μg·L~(-1)(normal模型);HC10为1.50μg·L~(-1)(logistic模型)和1.26μg·L~(-1)(normal模型);HC20为8.13μg·L~(-1)(logistic模型)和5.96μg·L~(-1)(normal模型);HC50为145.44μg·L~(-1)(logistic模型)和115.74μg·L~(-1)(normal模型)。据此判断水稻种植季节,稻田水域毒死蜱对食蚊鱼、鳑鲏、泽蛙蝌蚪、轮虫、常见腹足类和双壳类软体动物以及绝大多数藻类等的风险较小。利用冗余分析研究了生物物种数量、物种组成结构和拟合模型对HCx影响。结果表明:物种组成结构对HCx有较为明显的影响。具体表现为对毒死蜱较为敏感物种数量与HCx存在明显的负相关性;对毒死蜱不敏感的物种则与HCx呈现正相关性。 相似文献
92.
常用农药助剂类产品对水生生物效应研究进展 总被引:1,自引:0,他引:1
农药助剂是在农药制剂加工和使用中加入的除农药有效成分以外的其他辅助物质的总称。农药助剂在提高农药制剂药效、改善药剂性能、稳定制剂质量和降低活性成分危害等方面都起着相当重要的作用。几乎所有化学合成的农药原药都需添加农药助剂成为具有实际使用价值的农药制剂。农药助剂本身虽不具备对靶标生物的杀灭作用,但并不意味着其对环境或人体不具有危害性,部分现今仍在流通使用的农药助剂可导致健康危害,如致癌、致畸、致突变、危害神经系统,具有内分泌干扰作用等。截止目前,由于农药施用带来的农药助剂的危害问题很少引起研究人员关注,我国在农药助剂管理方面还是空白,亟需引起管理部门的重视并制订相关的防控法规。农药助剂种类繁多,我国习惯上将其分为非表面活性剂和表面活性剂两大类。本文总结了包括常用溶剂,非离子型、阳离子型和阴离子型表面活性剂在内的常用助剂对藻类、大型溞和鱼类等水生生物的急慢性毒性效应,并综述了烷基酚聚氧乙烯醚类助剂及其降解产物对水生生物的内分泌干扰效应。鉴于农药助剂对生态环境和人类的健康风险,本文还提出了我国农药助剂环境安全管理策略建议。 相似文献
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94.
Toward knowledge structuring of sustainability science based on ontology engineering 总被引:1,自引:1,他引:0
Terukazu Kumazawa Osamu Saito Kouji Kozaki Takanori Matsui Riichiro Mizoguchi 《Sustainability Science》2009,4(1):99-116
In sustainability science (SS), it is difficult to identify what needs to be solved, and it is also not clear how to solve the problems that are identified. There has been no consensus on the underlying question of “What is structuring knowledge in SS?” This paper focuses on knowledge structuring accompanied by supporting of thinking. It addresses the key challenges associated with knowledge structuring in SS, identifies the requirements for the structuring of knowledge, proposes a reference model, and develops an ontology-based mapping tool as a solution to one layer of the reference model. First, we identify the important requirements for SS knowledge structuring. Second, we develop a reference model composed of five layers based on three of the requirements. Third, we develop an ontology-based mapping tool at Layer 2 of the reference model for meeting the two major challenges for SS, namely, identifying what problems should be addressed in SS itself and proposing solutions for those problems. The tool is designed to store and retrieve information regarding SS, to provide access to a prototype ontology for SS, and to create multiple maps of conceptual chains depending on a user’s interests and perspectives. Finally, we assess whether the developed tool successfully realizes the targeted part of the reference model for SS by examining the tool’s conformity to the reference model, as well as its usability, effectiveness, and constraints. Although several issues were identified in the prototype ontology and the mapping tool, the study concluded that the mapping tool is useful enough to facilitate the function of Layer 2. In particular, the mapping tool can support thinking about SS from the viewpoint of: (a) finding new potentials and risks of technological countermeasures studied in SS; (b) helping users to get a more comprehensive picture of problems and their potential solutions; and (c) providing an effective opportunity to come up with new ideas that might not be thought of without such a tool. 相似文献
95.
Rapid Assessment of Urban Wetlands: Do Hydrogeomorphic Classification and Reference Criteria Work? 总被引:1,自引:0,他引:1
The Hydrogeomorphic (HGM) functional assessment method is predicated on the ability of hydrogeomorphic wetland classification
and visual assessment of alteration to provide reference standards against which functions in individual wetlands can be evaluated.
The effectiveness of this approach was tested by measuring nitrogen cycling functions in forested wetlands in an urbanized
region in New Jersey, USA. Fourteen sites represented three HGM classes and were characterized as “least disturbed reference”
or “non-reference” based on initial visual assessment. Water table levels and in situ rates of net nitrogen mineralization,
net nitrification, and denitrification were measured over one year in each site. Hydrological alterations, resulting in consistently
low or flashy water table levels, were not correlated with a priori designations as reference and non-reference. Although
the flat-riverine wetland class had lower net nitrification and higher denitrification rates than riverine or mineral flat
wetland classes, this difference was attributable to the lack of hydrologically-altered wetlands in the flat-riverine class,
and thus more consistently wet conditions. Within all HGM classes, a classification based on the long-term hydrological record
that separated sites with “normal,” saturated hydrology from those with “altered,” drier hydrology, clearly distinguished
sites with different nitrogen cycling function. Based on these findings, current practices for designating reference standard
sites to judge wetland functions, at least in urbanized regions, are ineffective and potentially misleading. At least one
year of hydrological monitoring data is suggested to classify wetlands into groups that have different nutrient cycling functions,
particularly in urban landscapes. 相似文献
96.
大亚湾海洋生物体中的砷 总被引:5,自引:0,他引:5
为也了解大亚湾海洋生物体As含量的背景水平,1993年大亚湾15个测站采集了海洋样品,对其As含量进行了测定和评价。鱼类,甲索类,头足类和贝类As含量的平均值分别为0.45×10^-6,4.70×10^-6,2.28×10^-6和5.57×10^-6,表现出明显的种类间差异。 相似文献
97.
水环境质量评价标准探讨 总被引:6,自引:0,他引:6
水环境质量评价指标是开展评价工作的依据,本文针对地表水体质量标准、底泥质量标准和水生生物质量标准及共统一结合问题进行了探讨,为全面开展水环境质量评价提供更科学的决策依据。 相似文献
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