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排序方式: 共有7264条查询结果,搜索用时 78 毫秒
281.
An indispensable asset at risk: merits and needs of chemicals-related environmental sciences 总被引:1,自引:1,他引:0
282.
Protection of the environment from ionising radiation in a regulatory context (protect): proposed numerical benchmark values 总被引:1,自引:1,他引:0
283.
Effects of acute γ-irradiation on the aquatic microbial microcosm in comparison with chemicals 总被引:1,自引:1,他引:0
Shoichi Fuma Nobuyoshi Ishii Hiroshi Takeda Kiriko Miyamoto Kei Yanagisawa Kazutaka Doi Isao Kawaguchi Nobuyuki Tanaka Yuhei Inamori Gennady G. Polikarpov 《Journal of environmental radioactivity》2009,100(12):1027-1033
Effects of acute γ-irradiation were investigated in the aquatic microcosm consisting of green algae (Chlorella sp. and Scenedesmus sp.) and a blue–green alga (Tolypothrix sp.) as producers; an oligochaete (Aeolosoma hemprichi), rotifers (Lecane sp. and Philodina sp.) and a ciliate protozoan (Cyclidium glaucoma) as consumers; and more than four species of bacteria as decomposers. At 100 Gy, populations were not affected in any taxa. At 500–5000 Gy, one or three taxa died out and populations of two or three taxa decreased over time, while that of Tolypothrix sp. increased. This Tolypothrix sp. increase was likely an indirect effect due to interspecies interactions. The principal response curve analysis revealed that the main trend of the effects was a dose-dependent population decrease. For a better understanding of radiation risks in aquatic microbial communities, effect doses of γ-rays compared with copper, herbicides and detergents were evaluated using the radiochemoecological conceptual model and the effect index for microcosm. 相似文献
284.
The system of radiological protection of the environment that is currently under development is one contribution to the general need to adequately protect the environment against stress. Dominated by operational goals, it emphasizes conceptual and methodological approaches that are readily accessible today: reference organisms supported by individual-based traditional ecotoxicological data. Whilst there are immediate advantages to this approach (pragmatism, consistency with other approaches in use for man and biota), there are also clear limitations, especially in a longer run perspective, that need to be acknowledged and further considered. One can mention a few: uncertainties generated by the need for various extrapolations (from lower to higher levels of biological organisation, …), various features missed such as potential ecological impact through impairment of ecosystem processes, trans-generational impacts as mediated through genomic instability, indirect effects mediated through trophic interactions or disruption of ecological balances,… Such limitations have already been faced in other fields of environmental protection against other stressors, pushing a number of environment professionals to assign stronger emphasis on more systemic approaches. This review discusses the advantages and limitations of the current approach designed for the radiological protection of non-human biota in the broader context of environment protection as a whole, with especial reference to upcoming trends and evolutions. This leads in particular to advocating the need to boost scientific and methodological approaches featuring the ecosystem concept as a mean to access a unified goal of protection: preserving life sustainability through protection of ecosystem structure and functioning. 相似文献
285.
This paper develops a method for identifying and assessing long-term supply risks for mineral raw materials. The method is based on a combined evaluation of past and future supply and demand trends. By analysing raw material boom and bust cycles over the past 50 years, we have quantified indicators and defined benchmarks for identifying critical market situations. By applying the method, risks for supply shortage may be identified at an early stage. In addition, a numerical evaluation model has been developed for better comparison between various mineral raw materials. Compared to other assessment methods this method uses specific benchmarks for each raw material to better assess supply risks. The method is embedded within a systematic and comprehensive analytical approach. 相似文献
286.
Balancing environmental and industry sustainability: A case study of the US gold mining industry 总被引:2,自引:0,他引:2
Bruce Finnie Jeffrey Stuart Linda Gibson Fern Zabriskie 《Journal of environmental management》2009,90(12):3690-3699
Mandatory insurance requirements and/or mitigation fees (royalties) for mining companies may help reduce environmental risk exposure for the federal government. Mining is examined since the Environmental Protection Agency (EPA) Toxic Release Inventory reveals that this sector produces more hazardous waste than any other industrial sector. Although uncommon, environmental expense can exceed hundreds of millions of dollars per development. Of particular concern is the potential for mines to become unfunded Superfund sites. Monte Carlo simulation of risk exposure is used to establish a plausible range of unfunded federal liabilities associated with cyanide-leach gold mining. A model is developed to assess these costs and their impact on both the federal budget and corporate profitability (i.e., industry sustainability), particularly if such costs are borne by offending firms. 相似文献
287.
OHS风险控制方法在烟气排放控制工程中的应用 总被引:1,自引:0,他引:1
介绍了烟气排放控制工程中OHS风险控制的方法,并以香港青山“B”电厂4X680MW机组排放控制工程(CPBEC)为例,阐述了目前国内外环保项目在OHS风险管理方面的差距和改进措施。 相似文献
288.
论焦化行业环境风险防范措施及应急预案 总被引:2,自引:0,他引:2
本文对焦化行业的原辅材料及产品的理化性质、生产过程中潜在的环境风险进行了识别,并在此基础上有针对性的提出了焦化行业环境风险防范措施及应急预案。 相似文献
289.
Patrick L. Witmer Paul M. Stewart Christopher K. Metcalf 《Journal of the American Water Resources Association》2009,45(3):734-747
Abstract: Unpaved road‐stream crossings increase sediment yields in streams and alter channel morphology and stability. Before restoration and sedimentation reduction strategies can be implemented, a priority listing of unpaved road‐stream crossings must be created. The objectives of this study were to develop a sedimentation risk index (SRI) for unpaved road‐stream crossings and to prioritize 125 sites in the Choctawhatchee watershed (southeastern Alabama) using this model. Field surveys involved qualitative and quantitative observations of 73 metrics related to waterway conditions, crossing structures, road approaches, and roadside soil erosion. The road‐stream crossing risk analyses involved elimination of candidate metrics based on redundancy, skewness, lack of data, professional judgment, lack of nonzero values, unbalanced box plots, and limited ranges of values. A final selection of 12 metrics formed the SRI and weighed factors involving soil erodibility, road sedimentation abatement features, and stream morphology alteration. The SRI was organized into narrative categories (excellent, good, fair, poor, and very poor) based on the distribution of scores. No excellent sites (scores ≥55) were found in this study, 17 (20.7%) were good (low sedimentation risk), 37 (45.1%) were fair (moderate sedimentation risk), 26 (31.7%) were poor (high sedimentation risk), and two (2.5%) were very poor (high sedimentation risk). There was no significant difference in SRI scores among crossing structure type (round culverts, box culverts, and bridges) (H = 4.31, df = 2, p = 0.058). A future study of the Choctawhatchee watershed involving the same study sites could assess the success of restoration plans and activities based on site score improvement or decline. 相似文献
290.
Wei-Chung Liu Ji-Liang Doong Sing-Ling Tsai Ching-Huei Lai Ming-Chang JengAuthor vitae 《Journal of Safety Research》2009,(6):461-468