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991.
兴仁高砷煤矿区溪流水系环境中砷自然净化的初步研究   总被引:1,自引:0,他引:1  
为了解矿山环境中砷的自然净化能力及其净化机制,对兴仁典型高砷煤矿区溪流水系环境进行采样分析。结果表明,研究区水体和沉积物中砷含量从上游到下游均呈不断降低的变化趋势,水体显示较强的自净能力。上游水体中砷含量的降低主要是吸附沉淀作用,而溪流的简单稀释作用在下游也显得非常重要。  相似文献   
992.
三峡水库是我国重要的生态屏障和水资源战略储备库,保护水库的水质安全对于国家经济发展和社会稳定具有重要战略意义.本文基于EFDC模型模拟了2010-2014年三峡库区及主要支流的水动力水质过程,重点研究上游来水和重点支流对库区水质的影响及水龄变化特征,结果表明:①模型可定量研究重点支流输入对库区水质的影响,17条支流中仅...  相似文献   
993.
在实验室内模拟研究的基础上,运用生理生态学的原理,研究了水盐胁迫对钠猪毛菜(salsola nitraria)和散枝猪毛菜(salsola brachiata)种子萌发的影响,结果显示,钠猪毛菜与散枝猪毛菜种子萌发的最适温度分别为25 ℃和15 ℃.在盐溶液和PEG溶液中,2种种子的萌发规律相似,即随着水势的降低,萌发率和萌发速率下降.在盐胁迫下钠猪毛菜和散枝猪毛菜种子萌发的最低水势接近-7.2 MPa;在水分胁迫下2种种子萌发的最低水势均未超过-2.0 MPa,其中,钠猪毛菜种子表现出较强的耐水分胁迫能力.在相同水势条件下,PEG对2种猪毛菜种子萌发的抑制程度显著大于等渗NaCl,说明渗透胁迫是影响2种植物种子萌发的主要因素.  相似文献   
994.
城市控制爆破工程采用电雷管网路起爆,极易发生爆破事故.运用FTA方法,编制了爆破事故树,并进行了定性分析.结合工程实际,提出了爆破事故的具体预防措施,更依法采取了爆破安全管理措施.  相似文献   
995.
为了评价新民柳河水源地的供水安全,简要介绍水环境健康风险评价基本方法的基础上,建立了水环境健康风险评价模式.研究结果表明:①柳河水源地地面水基因毒物质为优先控制污染物;而地下水应着力控制躯体毒物质.②对于基因毒物质,监测断面优先控制污染物为As和Cr;而对于躯体毒物质,所有监测断面的优先控制污染物均为氨.③在所有监测断面中,柳河上断面等6处有毒污染物所致健康危害的个人年总风险数量级为10-5-10-4.在日后的管理过程中,应对这6处加大治理力度.④目前环境健康风险评价还没有包括在常规环境评价工作中,建议在今后的评价工作中应该逐步开展这方面的工作,以提高供水安全.  相似文献   
996.
水环境质量评价3种方法的应用对比   总被引:6,自引:0,他引:6  
王娟  高原 《工业安全与环保》2007,33(2):16-17,64
从众多水质评价方法中选取单项指数法、加权均值型指数法、模糊数学法进行介绍,并通过运用这3种方法对大汶河某年监测数据的平均值进行评价.经对比分析发现,加权均值型指数法是一种比较实用的水质评价方法,模糊数学法可以作为必要的补充.  相似文献   
997.
介绍了湖北省清江高坝洲津洋口防护区的概况,对津洋口防护区水环境污染现状进行了分析和调查研究,同时得出了防护区的主要污染为工业废水污染.计算了津洋口防护区丹水河的水环境容量,并据此提出水环境污染治理方案.  相似文献   
998.
Epifaunal communities associated with macroalgae were exposed to storm water pulses using a custom made irrigation system. Treatments included Millipore freshwater, freshwater spiked with trace metals and seawater controls to allow for the relative importance of freshwater inundation, trace metals and increased flow to be determined. Experimental pulses created conditions similar to those that occur following real storm water events. Brief storm water pulses reduced the abundance of amphipods and gastropods. Freshwater was the causative agent as there were no additional effects of trace metals on the assemblages. Laboratory assays indicated that neither direct nor latent mortality was likely following experimental pulses and that epifauna readily avoid storm water. Indirect effects upon epifauna through salinity-induced changes to algal habitats were not found in field recolonisation experiments. Results demonstrate the importance of examining the effects of pulsed contaminants under realistic exposure conditions and the need to consider ecologically relevant endpoints.  相似文献   
999.
An ex vivo gill EROD assay was applied in Atlantic cod (Gadus morhua) as a biomarker for waterborne CYP1A-inducing compounds derived from oil production at sea. Exposure to nominal concentrations of 1 ppm or 10 ppm North Sea crude oil in a static water system for 24 h caused a concentration-dependent gill EROD induction. Further, exposure of cod for 14 days to environmentally relevant concentrations of produced water (PW, diluted 1:200 or 1:1000) from a platform in the North Sea using a flow-through system resulted in a concentration-dependent induction of gill EROD. Crude oil (0.2 ppm) from the same oil field also proved to induce EROD. Finally, gill EROD activity in cod caged for 6 weeks at 500-10 000 m from two platforms outside Norway was measured. The activities in these fish were very low and did not differ from those in fish caged at reference sites.  相似文献   
1000.
BACKGROUND, AIM AND SCOPE: Conjoint analysis and the related choice-modelling methods have been used for many years in marketing research to evaluate consumer behaviour and preferences for different kinds of product attributes. Recently, the number of applications in environmental science and management has started to grow. Conjoint analysis is found in many different forms, and the environmental studies evaluated in this review display the same range of methods as in other fields. The key characteristic of all these methods is that trade-offs are evaluated by jointly considering a number of important attributes. MAIN FEATURES: This paper is a review of the literature on environmental applications of conjoint analysis and assesses in which environmental area conjoint analysis has been most successful. The method and the design of the studies are reviewed as well. RESULTS: A total of 84 studies were found, dealing with environmental issues that were evaluated by conjoint analysis. The studies concern agriculture, ecosystem management, energy, environmental evaluation, forestry, land management, pollution, products, recreation, environmental risk analysis and waste management. DISCUSSION: Choice experiments seem to have a comparatively stronger position in environmental studies than elsewhere. Most of the environmental applications are related to natural resource management. This is somewhat surprising, but a number of reports have appeared also on product evaluation, which could be a key application area in the future. CONCLUSIONS: Compared to marketing and transportation, the number of environmental conjoint studies is rather small but increasing, and the method has proven to work effectively in eliciting preferences on environmental issues. In environmental issues, experimenters often use choice experiments, especially concerning ecosystem management and environmental evaluations. When it comes to evaluating preferences concerning agriculture, forestry, energy and products, a more traditional approach of conjoint analysis is favoured. RECOMMENDATIONS AND PERSPECTIVES: Two new areas of application are identified in this review--environmental communication and expert elicitation. Conjoint analysis can thus be developed into a useful instrument for environmental risk analysis and communication, both of which are necessary for an efficient approach to risk governance.  相似文献   
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