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121.
湘江干流水环境健康风险评价 总被引:35,自引:0,他引:35
为研究湘江水环境污染对人体健康产生的危害风险,在简要介绍健康风险评价方法及国内外研究、应用进展的基础上,建立了水环境健康风险评价模式,应用2000年的水质监测资料,对湘江干流主要断面进行了水环境健康风险评价.结果表明,在所评价断面中,非致癌物质由饮水途径所致健康危害的个人年风险按大小排列为Pb>Hg>NH3>酚;化学致癌物质由饮水途径所致健康危害的个人年风险按大小排列为As>Cd;化学致癌物质对人体健康危害的个人年风险远超过非致癌物质;污染最为严重的为松柏断面,其次是五星断面和三叉矶断面.湘江干流衡阳以上江段水质良好,衡阳以下江段水质较差.研究对湘江干流水污染防治方略的制定具有一定价值. 相似文献
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123.
1985-2005年中国城市水源地突发污染事件不完全统计分析 总被引:23,自引:0,他引:23
对1985-2005年中国城市水源地突发污染事件进行了统计分析,以从总体上揭示这些事件的发生规律及其对城市水源地和供水安全的危害.采用文献检索方法,通过对1985-2005年<中国环境报>、<人民日报>、新华网等报刊和网络的检索,从发生日期、地点、污染物种类、事件简况4个方面统计中国城市水源地突发污染事件,经整理和筛选后共列出102起.这些突发污染事件的分析结果表明:1)中国城市水源地突发污染事件总体上呈数量逐年增多,危害增大的趋势;2)化学品和污水是主要污染物;3)河道交通事故和工厂泄漏事故是主要风险源;4)突发污染事件一般都造成了比较严重的经济社会影响,但缺乏相应的应急管理机制和应急部门;5)3个典型突发污染事件造成重大经济社会损失并引发社会高度关注,凸现了构建中国城市水源地突发污染事件应急机制的重要性和迫切性. 相似文献
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125.
久效磷对黄鳝乙酰胆碱酯酶、羧酸酯酶和磷酸酶活性的影响 总被引:5,自引:0,他引:5
采用静态急性毒性实验方法,研究了久效磷对黄鳝脑乙酰胆碱酯酶及肝脏、肾脏羧酸酯酶、碱性磷酸酶、酸性磷酸酶活性的影响.结果表明,在水温(20±2)℃条件下,经0.25 mg·L-1、0.50 mg·L-1、1.00mg·L-1和2.00mg·L-1的久效磷暴露96 h,黄鳝肝脏、肾脏羧酸酯酶和脑乙酰胆碱酯酶活性均显著下降,但两者表现出不同的抑制模式.随着暴露质量浓度的升高,肝脏和肾脏羧酸酯酶活性的下降幅度逐渐变小,而脑乙酰胆碱酯酶活性下降幅度却由小变大.久效磷暴露黄鳝96 h,肝脏、肾脏酸性磷酸酶活性均升高;而肝脏碱性磷酸酶活性升高;肾脏碱性磷酸酶活性降低.久效磷暴露质量浓度与脑乙酰胆碱酯酶和肝脏、肾脏羧酸酯酶活性之间具有剂量-效应关系,酸性磷酸酶和碱性磷酸酶可能在鱼体抵御有机磷农药毒性作用中有着重要的作用,其机理有待进一步研究.此外,本文还探讨了有机磷农药靶标酶乙酰胆碱酯酶和解毒酶羧酸酯酶、磷酸酶之间的相关性. 相似文献
126.
战斗机座舱人机界面基本模型分析 总被引:1,自引:0,他引:1
讨论战斗机人机界面的组成部分及其功能,把各部分划分到飞行员和战斗机的三要素中,在此基础上建立了战斗机座舱人机界面三要素基本模型;通过分析要素组成部分间相互关系,利用不同的线条表示其不同程度的相互作用关系;对飞行员和战斗机的三要素组成部分进行了工效分析,进而探讨其在战斗机人机界面中的作用。通过人机界面模型的建立以及对战斗机座舱人机界面模型中的三要素进行的工效分析,得出了在人机界面中各个因素的重要程度及其功能作用,为战斗机座舱人机界面的设计提供了参考。 相似文献
127.
Using empirical models of species colonization under multiple threatening processes to identify complementary threat‐mitigation strategies 下载免费PDF全文
Ayesha I.T. Tulloch Alessio Mortelliti Geoffrey M. Kay Daniel Florance David Lindenmayer 《Conservation biology》2016,30(4):867-882
Approaches to prioritize conservation actions are gaining popularity. However, limited empirical evidence exists on which species might benefit most from threat mitigation and on what combination of threats, if mitigated simultaneously, would result in the best outcomes for biodiversity. We devised a way to prioritize threat mitigation at a regional scale with empirical evidence based on predicted changes to population dynamics—information that is lacking in most threat‐management prioritization frameworks that rely on expert elicitation. We used dynamic occupancy models to investigate the effects of multiple threats (tree cover, grazing, and presence of an hyperaggressive competitor, the Noisy Miner (Manorina melanocephala) on bird‐population dynamics in an endangered woodland community in southeastern Australia. The 3 threatening processes had different effects on different species. We used predicted patch‐colonization probabilities to estimate the benefit to each species of removing one or more threats. We then determined the complementary set of threat‐mitigation strategies that maximized colonization of all species while ensuring that redundant actions with little benefit were avoided. The single action that resulted in the highest colonization was increasing tree cover, which increased patch colonization by 5% and 11% on average across all species and for declining species, respectively. Combining Noisy Miner control with increasing tree cover increased species colonization by 10% and 19% on average for all species and for declining species respectively, and was a higher priority than changing grazing regimes. Guidance for prioritizing threat mitigation is critical in the face of cumulative threatening processes. By incorporating population dynamics in prioritization of threat management, our approach helps ensure funding is not wasted on ineffective management programs that target the wrong threats or species. 相似文献
128.
Cristi C. Horton Tarla Rai Peterson Paulami Banerjee Markus J. Peterson 《Conservation biology》2016,30(1):23-32
Conservation policy sits at the nexus of natural science and politics. On the one hand, conservation scientists strive to maintain scientific credibility by emphasizing that their research findings are the result of disinterested observations of reality. On the other hand, conservation scientists are committed to conservation even if they do not advocate a particular policy. The professional conservation literature offers guidance on negotiating the relationship between scientific objectivity and political advocacy without damaging conservation science's credibility. The value of this guidance, however, may be restricted by limited recognition of credibility's multidimensionality and emergent nature: it emerges through perceptions of expertise, goodwill, and trustworthiness. We used content analysis of the literature to determine how credibility is framed in conservation science as it relates to apparent contradictions between science and advocacy. Credibility typically was framed as a static entity lacking dimensionality. Authors identified expertise or trustworthiness as important, but rarely mentioned goodwill. They usually did not identify expertise, goodwill, or trustworthiness as dimensions of credibility or recognize interactions among these 3 dimensions of credibility. This oversimplification may limit the ability of conservation scientists to contribute to biodiversity conservation. Accounting for the emergent quality and multidimensionality of credibility should enable conservation scientists to advance biodiversity conservation more effectively. 相似文献
129.
AYESHA I. T. TULLOCH VIVITSKAIA J. D. TULLOCH MEGAN C. EVANS MORENA MILLS 《Conservation biology》2014,28(6):1462-1473
Understanding the social dimensions of conservation opportunity is crucial for conservation planning in multiple‐use landscapes. However, factors that influence the feasibility of implementing conservation actions, such as the history of landscape management, and landholders’ willingness to engage are often difficult or time consuming to quantify and rarely incorporated into planning. We examined how conservation agencies could reduce costs of acquiring such data by developing predictive models of management feasibility parameterized with social and biophysical factors likely to influence landholders’ decisions to engage in management. To test the utility of our best‐supported model, we developed 4 alternative investment scenarios based on different input data for conservation planning: social data only; biological data only; potential conservation opportunity derived from modeled feasibility that incurs no social data collection costs; and existing conservation opportunity derived from feasibility data that incurred collection costs. Using spatially explicit information on biodiversity values, feasibility, and management costs, we prioritized locations in southwest Australia to control an invasive predator that is detrimental to both agriculture and natural ecosystems: the red fox (Vulpes vulpes). When social data collection costs were moderate to high, the most cost‐effective investment scenario resulted from a predictive model of feasibility. Combining empirical feasibility data with biological data was more cost‐effective for prioritizing management when social data collection costs were low (<4% of the total budget). Calls for more data to inform conservation planning should take into account the costs and benefits of collecting and using social data to ensure that limited funding for conservation is spent in the most cost‐efficient and effective manner. 相似文献
130.