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61.
A method is proposed to build integrated models (also called Metamodels) aimed at quantifying the economic efficiency of air quality policies. This Metamodeling approach is based on the coupling of two complementary models, that operate at different scales in space and time, and which represent the economic and the physical and chemical processes, respectively. The joint consideration of the physico-chemical and techno-economic structure of the pollution control problems permits a comprehensive evaluation of air pollution abatement strategies. The motivating pollution control problems include urban-regional air quality management through efficient energy and traffic control policies. A pilot study, exploiting data collected in the Geneva canton (Switzerland), is used to demonstrate the potential of the approach.  相似文献   
62.
We present a planning framework that structures thelarge amount of interrelated information involved indeveloping regional monitoring programs. By regionalwe mean programs that recognize the importance ofprocesses that occur on larger geographic scales andthat cut across more than one ecosystem component. Theframework helps visualize functional relationshipsamong qualitative ingredients such as public concernsand more concrete details such as individual dataelements. It portrays the flow of information amongthe components of a regional program and ties eachaspect of the program to management decision-makingneeds. This makes it easier, during the planningprocess, to ensure that monitoring will actuallyproduce useful information. Further, the frameworksnovel, graphically oriented, and readily accessibleformat makes key information equally available to thewide range of participants (regulators, scientists,managers, public) whose input and support arenecessary for program success.  相似文献   
63.
农业土壤危险废物污染的风险管理   总被引:2,自引:0,他引:2  
从环境风险管理出发,探讨危险废物对农业土壤污染的途径,提出土壤危险废物污染的风险管理内容和方法,初步建立辽宁省农业土壤危险废物污染的预警指标体系。  相似文献   
64.
简要论述中小企业实施ISO 144001标准、建立 环境管理体系面临机遇和挑战,以及中小企业实施ISO 14001标准的对策。  相似文献   
65.
The landfill of municipal solid waste(MSW) could be regarded as denitrification reactor and involved in ammonia nitrogen biological removal process. In this research, the process was applied to municipal solid waste collected in Shanghai, China, which was characterized by high food waste content. The NH4^ removal efficiency in the system of SBR nitrifying reactor followed by fresh and matured landfilled waste layer in series was studied. In the nitrifying reactor, above 90% of NH4^ in leachate was oxidized to NO2^- and NO3^- . Then high concentrated NO2^- and NO3^- were removed in the way of denitrification process in fresh landfilled waste layer. At the same time, degradation of fresh landfilled waste was accelerated. Up to the day 120, 136.5 gC/(kg dry waste) and 17.9 gN/(kg dry waste) were converted from waste layer. It accounted for 50.15 % and 86.89 % of the total carbon and nitrogen content of preliminary fresh waste, which was 4.42 times and 5.17 times higher than that of reference column respectively. After filtering through matured landfilled waste, BOD5 concentration in leachate dropped to below 100 mg/L, which would not affect following nitrification adversely. Because the matured landfilled waste acted as a well methanogenic reactor, 23% of carbon produced accumulatively from fresh landfilled waste degradation was converted into CH4.  相似文献   
66.
猪场粪便微生物处理技术研究   总被引:8,自引:0,他引:8  
猪场粪便是重要污染源,但又是一类尚未充分利用的资源。采用生态工程与资源化综合技术处理猪场粪便,固态粪经堆肥发酵后转化成优质有机肥,粪水经厌氧产沼、光合细菌液肥化、水生植物氧化塘多级处理和资源化利用,出水可达排放标准,为猪场粪便的处置提供了一种可供选用的技术。  相似文献   
67.
在二升高压釜中,氮气氛条件下研究了有机磷农药废水的主要污染物质——硫代磷酸二乙酯(浓度为100ppm)的水解动力学.运用气相色谱法,在pH2—4,温度140—190℃范围,得到不同条件下的一级反应速率常数k,获得pH、温度与反应速率常数的关系,并对硫化磷酸二乙酯的水解条件进行了讨论.  相似文献   
68.
Supplementing the nutrient requirement of crops through organic manures plays a key role in sustaining soil fertility, and crop productivity and reducing use of fossil fuels. Field experiments were conducted for 2 years at two different locations (i.e. Lucknow and Pantnagar) in Uttar Pradesh, India. The objectives of the study were to assess the herb and essential oil yields of Japanese mint (Mentha arvensis cv. Hy 77), and its nutrient accumulation under single and combined applications of organic manures and inorganic fertilizers (NPK). Changes in physical and chemical characteristics of the soils (Fluvisols, Mollisols) were also determined. Eight treatments comprising different combinations of NPK through inorganic fertilizers and farm yard manure (FYM) were compared. The distilled waste of mint after extraction of essential oil was recycled to soils in the plots to supplement the nutritional requirement of the succeeding mustard crop (Brassica juncea cv. Pusa Bold). Herb and essential oil yield of mint were significantly higher with combined application of organic and inorganic sources of nutrients as compared to single applications. Accumulation of N and P was at par under full inorganic and combined supply whereas, K accumulation was higher with the former. Soil organic C and pH after harvest of mint did not significantly differ among the treatments, but the level of mineralizable N, Olsen-P and NH4OAc extractable K were higher in soil with integrated supply of nutrients. Significant increase in soil water stable aggregates, organic C, available NPK and microbial biomass, and decrease in soil bulk density were observed with waste recycling over fertilizer application. These benefits were reflected in the seed and stubble yield of mustard which succeeded mint. This study indicates that combined application of inorganic fertilizers with organics helps in increasing the availability of nutrients and crop yield and provides a significant effect to the succeeding crop. Similarly, recycling crop residues reduces the need for fossil fuel based fertilizer, and helps in sustaining and restoring soil fertility in terms of available nutrients and major physical and chemical characteristics of the soil.  相似文献   
69.
Anoveralldescriptionofindustrialwastewasgivenfromgeneration;treatment,disposalandemissionandcomprehensiveutilization.Inspiteo...  相似文献   
70.
松花江大顶子山枢纽工程建设后,库区内水体流线及扩散规律的变化将影响库区内水质,受沿江排污影响,其规划目标的水环境容量将发生改变,因此对建库后上游水质总量控制进行研究很有意义.  相似文献   
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