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491.
浅谈我国土壤问题特征及国外土壤环境管理经验借鉴   总被引:3,自引:2,他引:1  
随着我国社会经济的发展,土壤污染问题逐渐显露。而且我国土壤环境问题及污染防治工作在相当长时间内没有得到应有的重视,土壤污染问题逐渐暴露。加强土壤环境管理是我国土壤环境保护的一项基础性工作,具有十分重要的意义。本文研究分析我国与国外土壤环境问题的差异,总结美国、荷兰、日本三个国家土壤环境管理的经验及其借鉴意义,综合考虑我国发展国情、土壤环境问题特征及土壤环境管理基础,确定我国土壤环境管理要依靠"行政推动和法律监管相结合",提出一个涵盖土壤环境法律法规、标准、技术和装备能力建设(监测、监管、监理、风险管控)、人员队伍建设的适应我国土壤环境问题特征的综合环境管理体系。  相似文献   
492.
环境公益诉讼立法问题研究   总被引:2,自引:0,他引:2  
随着社会生产力的飞速发展,环境问题日益突出。环境公益诉讼是解决环境问题,保护国家、社会和公众环境权益的基本形式和有效途径,也是最后屏障。从国内一起环境公益诉讼案件出发,借鉴国外特别是美国环境公益诉讼的经验,提出了建立我国环境公益诉讼制度的若干立法建议,旨在探索一条落实科学发展观的环境保护新思路。  相似文献   
493.
● A hydrodynamic-Bayesian inference model was developed for water pollution tracking. ● Model is not stuck in local optimal solutions for high-dimensional problem. ● Model can estimate source parameters accurately with known river water levels. ● Both sudden spill incident and normal sewage inputs into the river can be tracked. ● Model is superior to the traditional approaches based on the test cases. Water quality restoration in rivers requires identification of the locations and discharges of pollution sources, and a reliable mathematical model to accomplish this identification is essential. In this paper, an innovative framework is presented to inversely estimate pollution sources for both accident preparedness and normal management of the allowable pollutant discharge. The proposed model integrates the concepts of the hydrodynamic diffusion wave equation and an improved Bayesian-Markov chain Monte Carlo method (MCMC). The methodological framework is tested using a designed case of a sudden wastewater spill incident (i.e., source location, flow rate, and starting and ending times of the discharge) and a real case of multiple sewage inputs into a river (i.e., locations and daily flows of sewage sources). The proposed modeling based on the improved Bayesian-MCMC method can effectively solve high-dimensional search and optimization problems according to known river water levels at pre-set monitoring sites. It can adequately provide accurate source estimation parameters using only one simulation through exploration of the full parameter space. In comparison, the inverse models based on the popular random walk Metropolis (RWM) algorithm and microbial genetic algorithm (MGA) do not produce reliable estimates for the two scenarios even after multiple simulation runs, and they fall into locally optimal solutions. Since much more water level data are available than water quality data, the proposed approach also provides a cost-effective solution for identifying pollution sources in rivers with the support of high-frequency water level data, especially for rivers receiving significant sewage discharges.  相似文献   
494.
废水处理设施竣工验收监测需注意的几个问题   总被引:3,自引:0,他引:3  
就废水处理设施竣工验收监测中存在的问题,提出几点看法和建议,这将有助于设计单位的设计,企业的运行管理和环保部门的监测.  相似文献   
495.
A collaborative problem-solving approach was applied to environmental impact assessment of regional waste management strategy in Pirkanmaa, Finland. Various actors—interest groups, authorities, and experts—were invited to engage in joint fact finding and to exchange their views on the goals of alternative waste management strategies. The experiences of these encounters suggest that collaborative EIA can serve as a learning and civic discovery process where people can act together and find new solutions. During the process, the participants were able to reflect on their preferences and factual beliefs and to create a previously unconsidered waste management strategy that most parties found acceptable. The potential for learning and finding mutually acceptable solutions depended, however, on the legitimacy and institutional settings of the process: to what extent different perspectives were considered in the process, not only included, and how EIA was connected to a political decision-making process.  相似文献   
496.
Inverse geochemical modeling from PHREEQC, and multivariate statistical methods were jointly used to define the genetic origin of chemical parameters of groundwater from the Voltaian aquifers in the Afram Plains area. The study finds, from hierarchical cluster analysis that there are two main hydrochemical facies namely the calcium-sodium-chloride-bicarbonate waters and the magnesium-potassium-sulfate-nitrate waters in the northern and southern sections, respectively, of the Afram Plains area. This facies differentiation is confirmed by the distribution of the SO(4)(2-)/Cl(-) ratio, which associates groundwater from the northern and southern sections to areas influenced by contact with evaporites and seawater, respectively. Principal component analysis (PCA) with varimax rotation using the Kaiser criterion identifies four principal sources of variation in the hydrochemistry. Mineral saturation indices calculated from both major ions and trace elements, indicate saturation-supersaturation with respect to calcite, aragonite, k-mica, chlorite, rhodochrosite, kaolinite, sepiolite, and talc, and undersaturation with respect to albite, anorthite, and gypsum in the area. Inverse geochemical modeling along groundwater flowpaths indicates the dissolution of albite, anorthite and gypsum and the precipitation of kaolinite, k-mica, talc, and quartz. Both the PCA and inverse geochemical modeling identify the incongruent weathering of feldspars as the principal factors controlling the hydrochemistry in the Afram Plains area. General phase transfer equations have been developed to characterize the geochemical evolution of groundwater in the area. A very good relationship has been established between calcite and aragonite saturation indices in the Afram Plains area, with R(2)=1.00.  相似文献   
497.
文章以抽样调查数据为基础,从人员、任务、地位等方面详细分析制约当前环境监测系统效能发挥的问题,提出引导环境监测站纳入公益一类事业单位、进一步提升监测站系统能力建设水平和切实保障环境监测系统运行经费是破解当前矛盾的关键。  相似文献   
498.
氨氮在线自动监测仪已在我国水质自动监测系统中得到广泛应用。其生产厂家日趋成熟、相关标准逐步出台、仪器性能基本达标。但在实际应用过程中,该仪器仍有许多问题需要进一步认识与改进。本文从方法选择、干扰排除、国家标准、比对、质量控制等几个方面,分析了该仪器存在的问题,并提出了相关建议。  相似文献   
499.
环境执法难、难执法的现象在我国普遍存在,本文结合乌鲁木齐市环境行政执法的现状,总结和分析了环境执法中所存在的问题及影响执法难的原因,并提出了进一步强化环境执法的对策和建议。  相似文献   
500.
建设社会主义新农村,是党中央运用科学发展观破解三农问题的新理念和新实践,是中国特色社会主义现代化的必然要求,是建设社会主义和谐社会的战略举措,也是增进农民福祉、惠及广大农民群众的民心工程。金融作为现代经济的核心,责无旁贷,义不容辞的要充分发挥杠杆作用,肩负起支持新农村建设与特色产业可持续发展的历史重任,紧密结合当地实际,不断创新金融产品,积极优化信贷结构,着力提升服务水平,切实解决金融支持乏力、担保机构缺位、农业保险缺失、信用环境不佳等诸多困难与问题,尚需研究和解决。本文以平凉市为例,进行了实证分析与思考。  相似文献   
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