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1.
浦东新区工业结构的多目标优化研究   总被引:2,自引:0,他引:2  
从经验和环境协调发展角度出发,用改进的多目标规划法研究浦东新区工业结构优化调整。以1989年为基准年,根据该年资料选取经济和环境影响较显著的十三个主要待业的产值为决策变量,设定调整目标,建立规划模型,并按照污染量增加率的不同设计方案。经过计算机数学模拟,提出既满足经济要求,又使污染量增加率尽可能降低的优化方案,将工业结构调整与污染控制结合起来,确定2000年规划年份的浦东新区工业结构优化。  相似文献   

2.
运用Kaya模型对农业碳排放量、经济增长、技术水平、人口规模因素进行分解,结果显示:除经济效应外,能源效应、技术效应、人口效应均为负值。大连市在农业经济快速发展的同时,也极大地促进了温室气体的排放。而农业能源结构的调整、生产技术的进步和农业人员的减少缓解了农业碳减排的压力,其中技术效应的贡献最为突出,农业技术的提高是现阶段大连市农业碳减排的主要驱动因素。  相似文献   

3.
以济南市为研究对象,通过构建环境与经济协调发展指标体系,分析了济南市生态环境和经济发展状况,评价了环境与经济协调发展水平,结果表明:2011年-2014年济南市经济发展呈逐年上升趋势;生态环境质量出现下降态势;环境与经济协调发展水平也出现了明显下滑.根据评价结果,探讨了该市在产业能源结构、机动车控制及农业生产方面存在的问题,由此提出了调整产业结构、优化能源结构、完善机动车管理、加强生态农业建设、建立环境和经济发展综合决策和激励机制等对策.  相似文献   

4.
农业面源污染已成为我国流域污染的主要来源,并已威胁到城乡居民的饮水安全,影响社会经济的可持续发展.三峡库区是生态脆弱区,水资源安全对促进库区生态环境保护与区域经济社会和谐发展尤为重要.为探明三峡库区重庆段农业面源污染与流域水资源安全演进变化的过程与内在机制,根据DPSIR框架原理,运用结构方程模型进行分析,并评价了2000-2011年流域水资源安全程度.结果表明:流域水资源安全程度分为两个阶段,2000-2005年水资源安全等级从一般安全下降到很不安全,2005-2011年水资源安全等级从很不安全上升到安全,出现阶段变化的主要原因在于从2006年开始,政府认识到流域生态环境的重要性并加大了对农业面源污染的控制力度,加强了对水土流失的治理.因此,为有效地减缓农业面源污染、改善流域水体质量,需要调整农业经济发展方式和农业产业结构,依靠科学技术提高农业生产效率,降低农用化学药品的投入,推广有机农业、改善耕地质量;加强水资源监督管理,实施农业生产节水措施;进一步加强面源污染控制投入,有效控制水土流失程度以减缓面源污染,实现流域水资源安全可持续利用.  相似文献   

5.
杜宝汉 《环境科学》1990,11(6):50-54
本文从区域生态经济系统的高层次对大理州人口、资源、经济、环境各子系统的动态关系进行分析研究。结果表明,建国以来,大理州经济发展迅速,工业总产值比1949年增长63倍,农业总产值增长了20倍。但是,由于人口数量激增对自然资源的需求量越来越大,区域生态系统遭到破坏。森林资源锐减,水土流失严重,水资源减少,环境污染等影响经济的持续发展。本文提出发展大理州生态经济的对策:①控制人口增长;②提高森林覆盖率;③调整经济结构;④控制环境污染。  相似文献   

6.
水资源约束地区种植结构优化研究——以华北地区为例   总被引:13,自引:1,他引:12  
在水资源短缺地区,除了节水灌溉技术、节水栽培技术之外,调整种植结构也是农业节水的一项重要技术措施。论文综合考虑区域社会、经济、环境协调发展,构建了区域节水高效种植结构调整的多目标模糊优化模型,克服了以往模型研究中存在的只注重经济效益而忽视社会和生态效益的局限性。并应用该模型对水资源严重短缺的华北地区进行实证研究,通过对该区种植结构调整的定量分析运算,提出了该区2010年和2030年的节水高效种植结构优化调整方案,该方案重点压缩了高耗水作物种植比例,扩大了低耗水作物种植比例,种植业用水效率逐步提高。  相似文献   

7.
水环境保护与经济发展决策模型的研究   总被引:19,自引:0,他引:19  
采用模块化设计思想 ,构建了水环境保护与经济发展的决策模型 ,主要模型有水资源需求模型、水环境容量模型、宏观经济模型、水污染控制模型、经济结构优化模型等。通过对多级模型的求解 ,获得既符合经济发展目标 ,又满足环境保护要求的合理的经济结构和合适的发展速度。从而为水资源保护与经济发展的研究提供可借鉴的思路和方法。  相似文献   

8.
为探究河北省永定河流域农业非点源污染的时空分布规律,研究在RS和GIS的基础上,利用输出系数模型对河北省永定河流域的农业非点源污染进行了来源分析、负荷计算、分布模拟和规律研究。结果表明:该区农业非点源污染在时间分布上主要集中于丰水年及丰水期,在空间分布上主要集中在平原区、耕地(尤其是坡耕地)、经济作物种植区、化肥农药强施用区、农村人口集聚区。因此,优化农业用地结构、调整作物种植结构、改善农业耕作方式、集中处理农村生活/养殖污水和加强农村固废管理等措施是流域农业非点源污染控制的重要途径。  相似文献   

9.
发展低碳产业,符合经济发展的价值理念和趋势。通过低碳经济背景下大连产业结构调整的现状分析、针对大连市低碳产业的发展现实,构建了大连低碳经济产业体系的结构模型;随着大连市循环低碳的新型绿色产业体系的建立与完善,分别从制度、技术与文化3个层面提出大连产业结构调整适应低碳经济要求的应对策略。  相似文献   

10.
农村环境的综合整治与保护是与农业现代化紧密相联的。农业现代化就是运用现代科学理论,不断地实现自然力、技术、经济三者有效地、科学地结合过程。我们要建设的是一个具有高效率的农业生态结构和经济及电子机械化、有效管理和控制的技术体系,  相似文献   

11.
Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis (DGGE) and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity (both in gene richness and diversity index values) and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor (50 mg/kg) recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos (150 mg/kg) caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos (250 mg/kg) produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes (bands) responded differently to the impact of agrochemicals: four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.  相似文献   

12.
The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.  相似文献   

13.
Several main metabolites of benzo[a]pyrene (BaP) formed by Penicillium chrysogenum, Benzo[a]pyrene-1,6-quinone (BP 1,6- quinone), trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene (BP 7,8-diol), 3-hydroxybenzo[a]pyrene (3-OHBP), were identified by high-performance liquid chromatography (HPLC). The three metabolites were liable to be accumulated and were hardly further metabolized because of their toxicity to microorganisms. However, their further degradation was essential for the complete degradation of BaP. To enhance their degradation, two methods, degradation by coupling Penicillium chrysogenum with KMnO4 and degradation only by Penicillium chrysogenum, were compared; Meanwhile, the parameters of degradation in the superior method were optimized. The results showed that (1) the method of coupling Penicillium chrysogenum with KMnO4 was better and was the first method to be used in the degradation of BaP and its metabolites; (2) the metabolite, BP 1,6-quinone was the most liable to be accumulated in pure cultures; (3) the effect of degradation was the best when the concentration of KMnO4 in the cultures was 0.01% (w/v), concentration of the three compounds was 5 mg/L and pH was 6.2. Based on the experimental results, a novel concept with regard to the bioremediation of BaP-contaminated environment was discussed, considering the influence on environmental toxicity of the accumulated metabolites.  相似文献   

14.
Sorption of chlorotoluron in ammonium sulfate, urea and atrazine multi-solutes system was investigated by batch experiments. The results showed application of nitrogen fertilizers to the soil could affect the behavior of chlorotoluron. At the same concentration of N, sorption of chlorotoluron decreased as the concentration of atrazine increased on the day 0 and 6 in soil, respectively. The sorption of chlorotoluron increased from 0 to 6 d when soils were preincubated with deionized water, ammonium sulfate and urea solution for 6 d. That indicated incubation time was one of the most important factors for the sorption of chlorotoluron in nitrogen fertilizers treatments. The individual sorption isotherms of chlorotoluron in rubbery polymer and silica were strictly linear in single solute system, but there were competition sorption between pesticides or between pesticides and nitrogen fertilizers. That indicated the sorption taken place by concurrent solid-phase dissolution mechanism and sorption on the interface of water-organic matter or water-mineral matter.  相似文献   

15.
Laogang landfill near Shanghai is the largest landfill in China, and receives about 10000 t of daily garbage per day, Samples of topsoil and plants were analyzed to evaluate mercury pollution from the landfill. For topsoil samples, there were significant correlations among total mercury (HgT), combinative mercury (Hgc) and gaseous mercury (HgG), and content of total organic carbon (TOC), but, no significantly relationship was found between Hg content and filling time. Hg content changes in vertical profiles with time showed that the average Hgv of profiles 1992, 1996, and 2000 was similar, but their average HgG was quite different. HgT was significantly correlated with Hgc in profile 1992 and 2000, and Hgv was significantly correlated with Hg6 in profile 1996. HgG/Hgv ratio in profile samples decreased in the order of (HgG,/HgT)1992〉(HgG/HgT)1996〉〉(HgG/HgT)2000. A simple outline of Hg release in landfill could be drawn: with increasing of filling time, degradation undergoes different biodegradation, accordingly, gaseous mercury goes through small, more, and small proportion to total mercury. Distribution of Hg in plants was inhomogeneous, following the order of leaf〉root〉stem. The highest value of leaf may be associated with higher atmospheric Hg from landfill. Ligneous plants (e.g. Phyllostachys glanca, Prunus salicina and Ligustrum lucidum) are capable of enriching more Hg than herbaceous plants.  相似文献   

16.
Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils.Bidens maximowicziana is a new Pb hyperaccumulator,which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb.The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues.The Pb distribution order in the B. maximowicziana was:leaf>stem>root.The effect of amendments on phytoremediation was also studied.The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application.Compared with CK(control check),EDTA application promoted translocation of Pb to overground parts of the plant.The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg.This research demonstrated that B.maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil,especially,combination with EDTA.  相似文献   

17.
Decomposition of alachlor by ozonation and its mechanism   总被引:1,自引:0,他引:1  
Decomposition and corresponding mechanism of alachlor, an endocrine disruptor in water by ozonation were investigated. Results showed that alachlor could not be completely mineralized by ozone alone. Many intermediates and final products were formed during the process, including aromatic compounds, aliphatic carboxylic acids, and inorganic ions. In evoluting these products, some of them with weak polarity were qualitatively identified by GC-MS. The information of inorganic ions suggested that the dechlorination was the first and the fastest step in the ozonation of alachlor.  相似文献   

18.
The influence of the nonionic surfactant Tween 80 on pentachlorophenol (PCP) oxidation catalyzed by horseradish peroxidase was studied. The surfactant was tested at concentrations below and above its critical micelle concentration (CMC). Enhancement of PCP removal was observed at sub-CMCs. The presence of Tween 80 in the reaction mixture reduced enzyme inactivation which occurred through a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in the presence or absence of Tween 80. At supra-CMCs, the surfactant caused noticeable reductions in PCP removal, presumably through micelle partitioning of PCP which precluded the hydrophobic PCP molecule from interacting with the enzyme.  相似文献   

19.
In this study an effort has been made to use plant polyphenol oxidases; potato (Solanum tuberosum) and brinjal (Solanum melongena), for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation.  相似文献   

20.
RemovalofheavymetalsfromsewagesludgebylowcostingchemicalmethodandrecyclinginagricultureWuQitang,NyirandegePascasie,MoCehuiF...  相似文献   

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