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731.
对新鲜渗滤液和经浓缩后渗滤液的臭气进行生物技术处理实验研究。实验结果表明,所采用的菌剂对两种渗滤液的臭气均有十分明显的去除效果。经生物技术处理后的两种渗滤液的各种污染物指标均有明显降低,其中大肠菌群去除率均达到了100%,氨氮的去除率分别为69.1%和58.2%,COD的去除率分别为84.8%和57.4%,总磷的去除率分别为97.7%和66.5%。该方法实现了从源头上防止渗滤液臭气产生的目标。  相似文献   
732.
针对不确定环境下应急物流设施选址方案评价问题,提出一种基于区间二型模糊集(IT2F)-最优最劣法(BWM)-多属性边界近似区域比较法(MABAC)的应急物流设施选址方案评价方法。首先,针对应急物流设施选址方案评价过程中评价信息的模糊不确定性问题,采用IT2F处理,并利用MABAC对选址方案排序;然后,针对传统的MABAC中属性权重需要从外部获得的问题,采用基于IT2F的BWM确定属性的权重;最后,将所提方法应用于某城市应急物流设施选址方案评价研究,并验证所提选址方法的可行性和有效性。结果表明:所提方法能够解决不确定环境下应急物流设施选址问题,同时能够保证方案评价的质量。  相似文献   
733.
环境监测是环境管理和决策的重要技术支持,环境监测质量管理工作与环境监测整体发展不相适应的矛盾日益突出。目前环境监测质量管理工作中存在的机构制度不健全、质量管理技术发展缓慢、现场监测质量管理薄弱等问题,可通过完善制度、转变工作方式、发挥质量监督员作用、加强现场监测质量管理、拓展质量管理范围等全面加强环境监测质量管理工作的措施得到解决。  相似文献   
734.
垃圾填埋场建设项目的主要环境问题包括:渗沥液排放、地下水环境污染、大气环境污染、噪声污染、景观变化和环境安全。根据工作经验,建立了包括建设项目基本情况、生态环境影响、社会环境影响、生态环境保护措施四大类调查监测指标为核心的环保验收调查指标体系,提出了文件资料核实、现场勘查、遥感调查、公众意见调查、环境监测和摄影法为主的建设项目竣工环保验收调查技术方法。  相似文献   
735.
文章分析了长庆油田井场废水特点,研制了三种适合于长庆油田井场废水处理的絮凝剂。将研发的絮凝剂与普通PAM分析进行对比,新型絮凝剂对色度及石油类的去除比常规PAM去除率提高了50%左右,悬浮物及COD的去除率亦分别提高了20%和30%。现场应用表明,研发的絮凝剂具有良好的应用效果。  相似文献   
736.
ABSTRACI:. Slash burning is a common site preparation technique used after timber harvest throughout the Southeastern United States. Little quantitative information exists on the hydrologic response to burn severity. This study compared the effects of low-severity and high-severity burns on runoff and sediment yields during rainfall simulation and during natural rainfall in the Southern Appalachian Mountains. Fire severity was largely determined by moisture conditions of the forest floor prior to ignition. Runoff and sediment yield variability was high between plots within the same treatment area due to differences in forest floor characteristics and infiltration rates. Conditions of high-severity resulted when burning was conducted with relatively dry fuels. Sediment yields were 40-times greater for the high-severity treatment areas than the low-severity treatment areas.  相似文献   
737.
本文介绍了葫芦岛市龙湾新区污水厂厂址及生物处理工艺等的选择。通过技术经济比较,选择建二处污水厂分别处理新、老城区的污水,并建两座小型地埋式污水处理站,选择SBR工艺作为新区污水处理厂二级生物处理工艺。  相似文献   
738.
    
ABSTRACT: A stratified, spatially balanced sample with unequal probability selection was used to design a multipurpose survey of headwater streams in the Mid‐Atlantic Coastal Plain. Objectives for the survey include unbiased estimates of regional stream conditions, and adequate coverage of unusual but significant environmental settings to support empirical modeling of the factors affecting those conditions. The design and field application of the survey are discussed in light of these multiple objectives. A probability (random) sample of 175 first‐order nontidal streams was selected for synoptic sampling of water chemistry and benthic and riparian ecology during late winter and spring 2000. Twenty‐five streams were selected within each of seven hydrogeologic subre‐gions (strata) that were delineated on the basis of physiography and surficial geology. In each subregion, unequal inclusion probabilities were used to provide an approximately even distribution of streams along a gradient of forested to developed (agricultural or urban) land in the contributing watershed. Alternate streams were also selected. Alternates were included in groups of five in each subregion when field reconnaissance demonstrated that primary streams were inaccessible or otherwise unusable. Despite the rejection and replacement of a considerable number of primary streams during reconnaissance (up to 40 percent in one subregion), the desired land use distribution was maintained within each hydrogeologic subregion without sacrificing the probabilistic design.  相似文献   
739.
城市生活垃圾填埋场恶臭污染与周边限建区划分探讨   总被引:1,自引:0,他引:1  
鱼红霞  余杰 《四川环境》2010,29(2):100-103,108
随着我国城市垃圾状况和城市建设的变化,填埋场气体问题日益突出。探讨环境影响评价中如何合理确定垃圾填埋场周边建设的控制距离,科学设置垃圾填埋场的防护距离,已成为解决恶臭污染问题的有效途径之一。文章将恶臭污染影响作为限制性因素,提出垃圾填埋场周边限建区的概念,并探讨了划分思路和原则,最后文章从恶臭污染控制因子选取、恶臭污染影响计算模式及参数选取等对恶臭污染防护距离进行了讨论,在此基础上对垃圾填埋场周边限建区的划分方法进行了具体说明。文章探讨的基于垃圾填埋场恶臭污染影响的限建区划分方法,对垃圾填埋场环境影响评价及垃圾填埋场周边建设项目规划具有一定的参考意义。  相似文献   
740.
Multiple attribute evaluation of landscape management   总被引:1,自引:0,他引:1  
Economic approaches to the valuation of ecological services have several limitations. Some of these limitations can be overcome using the multiple attribute decision-making model developed in this paper. The model postulates that a private or public decision-maker selects a site/landscape management plan based on the biophysical and economic attributes of alternative management plans, the decision-maker’s preferences for attributes, and constraints on the selection of a management plan.Two cases are examined. Case A is a watershed consisting of publicly owned land that is managed at the site, management unit and landscape scales. Management is based on the philosophy of ecosystem management. Case B is a watershed composed of several privately owned units that are managed at the site scale by decision-makers whose primary motivation is economic profit. The preferred management plan in both cases is determined using a two-stage procedure. The first stage uses a stochastic programming model to identify the most efficient management plans for a site/landscape. The second stage determines which efficient management plan for a site/landscape is preferred by maximizing an expected utility function that is additive in the attributes and assumes that the decision-maker is risk neutral.Whether a land-management plan results in strongly or weakly sustainable resource conditions is evaluated. Strong sustainability requires the probability of exceeding the minimum acceptable value of an attribute to be greater than or equal to a pre-determined reliability level for each attribute. Weak sustainability requires the same condition except that it applies to a composite index of the attributes rather than each attribute. Bayes theorem is used to evaluate uncertainty about whether the state of a landscape is sustainable.  相似文献   
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