基于离散仿真分析的废弃电器电子产品回收网络优化

优化电子废弃物回收网络对控制回收成本、降低环境污染具有重要意义.因此,本文建立了一种综合考虑运输、存储及淡旺季的回收过程离散仿真模型,提出了一种以经济、能源及环境为指标的回收网络评价方法.同时,以安徽省为例,结合现有回收模式,分别设计了4种回收网络布局及运输方案,在不同的回收覆盖率及库存能力条件下以回收成本、燃油消耗及CO2排放为优化目标对比分析各备选方案,提出了在报废量大于0.15万t·a-1的地区建立回收点并采取全局运输模式的最优方案.研究表明,本文提出的方法同样适用于我国其他省市回收网络的优化.     

基于CREP的国家环境质量改善工程规划与管理:以《大气污染防治行动计划》为例

重大环保工程管理是我国国家环境保护规划制度的重要组成和实施基础。对国家重大环保工程管理的演变和模式特征进行回顾,认为基于CREP的环境质量工程管理模式是适应国家环境质量管理转型的新模式,主要包括环境容量下的削减规模确定、给定削减规模的工程方案设计、基于减排工程的环境质量和健康效果评估、支撑减排和环境质量改善的配套政策等管理模块。最后,以《大气污染防治行动计划》为例,证明了基于CREP的环境质量工程管理模式的可行性和有效性。     

武汉地区基坑一般黏性土的力学特性与其物理指标间的相关性研究

一般黏性土作为武汉地区基坑工程中常见土层,对其工程特性与其物理力学参数的相关性研究对提高深基坑支护技术和经济性具有重要的现实意义。为研究武汉地区基坑工程典型一般黏性土的物理力学特性,以武汉地区45个基坑工程为基础,采用数理统计及回归分析方法,分析了武汉地区一般黏性土的工程特性与其物理力学参数间的相关关系。结果表明:武汉地区基坑工程一般黏性土的静力触探指标PS值变化范围为0.8~1.6 MPa,标准贯入指标N值的变化范围为3~7,土体饱和度较高,可塑及压缩性中等偏高,这将对基坑及高层建筑沉降变形产生不利影响;此外,一般黏性土的含水率、孔隙比、液限系数与直剪试验条件下抗剪强度指标c、值间呈负相关关系,一般黏性土的压缩模量与直剪试验条件下抗剪强度指标c、值间呈正相关关系。该研究结果可为武汉地区基坑工程设计的参数取值提供依据。     

Development of collision risk indicators for autonomous subsea inspection maintenance and repair

The objective of this article is to present a method for developing collision risk indicators applicable for autonomous remotely operated vehicles (AROVs), which are essential for promoting situation awareness in decisions support systems. Three suitable risk based collision indicators are suggested for AROVs namely, time to collision, mean time to collision and mean impact energy. The proposed indicators are classified into different thresholds; low, intermediate and high. An AROV flight path is simulated to gather input data to calculate the proposed indicators and three collision targets are established, i.e., subsea structure, seabed and a cooperating AROV. The proposed indicator development method together with the case study show a proof-of-concept that the combination of mean time to collision and mean impact energy indicators can identify risk prone waypoints in the AROV path. The method results in an overall risk picture for a given AROV path. The results may provide useful input in replanning of mission paths and for implementation of risk reducing measures. Even though the method focuses on collision risk, it can be used for other accident scenarios for AROVs.     

国内流域生态系统土壤动物群落结构研究

土壤动物与其生存环境息息相关.土壤质地优良,食物种类丰富多样,则土壤动物个体数、类群数、多样性显著增多.目前,国内学者多侧重研究农田、森林、草原等生态系统土壤动物群落结构,而流域生态系统土壤动物研究较少涉及.对此,从土壤动物的水平分布、垂直分布和群落多样性三个方面来综述流域生态系统相关因素对土壤动物的影响具有代表性.在此基础上借鉴其他生态系统土壤动物相关研究并且结合流域生态系统自身特点拓展土壤动物研究方向,为研究区土地利用方向提供依据.研究流域中不同环境因素对土壤动物区系的影响,了解国内外土壤动物的研究和流域生态系统对土壤动物影响的进展.对于生态环境的恢复与重建具有重大意义.     

利用空气自动监测车仪器对空气自动监测站仪器进行质量保证及质量控制的可行性分析

通过对辖区内空气自动监测车仪器与4家公司空气自动监测站仪器的比对分析,得出了空气自动监测车仪器与空气自动监测站仪器的PM10、SO2、NO2相对误差分别为:-32.8%、4.4%、-8.7%,仪器之间显现出良好的线性关系,从比对结果来看,利用空气自动监测车对空气自动监测站进行质量保证和质量控制是可行的.     

Evaluating farm performance using agri-environmental indicators: recent experiences for nitrogen management in The Netherlands

Intensive agriculture, characterized by high inputs, has serious implications on the environment. Monitoring and evaluation of projects aiming at designing, testing and applying more sustainable practices require instruments to asses agronomic as well as environmental performance. Guidelines for Good Agricultural Practice (GAP) or Good Farming Practice (GFP) define sustainable practices but give limited insight into their environmental performance. Agri-environmental indicators (AEIs) provide information on environmental as well as agronomic performance, which allows them to serve as analytical instruments in research and provide thresholds for legislation purposes. Effective AEIs are quantifiable and scientifically sound, relevant, acceptable to target groups, easy to interpret and cost-effective. This paper discusses application of four AEIs for nitrogen (N) management in three Dutch research projects: 'De Marke', 'Cows and Opportunities' and 'Farming with a future'. 'De Marke' applied Nitrogen Surplus and Groundwater Nitrate Concentration in the design and testing of environmentally sound dairy systems. 'Cows and Opportunities', testing and disseminating dairy systems designed at 'De Marke', mainly applied Nitrogen Surplus, while 'Farming with a future' used Nitrogen Surplus, Groundwater Nitrate Concentration and Residual Mineral Soil Nitrogen to support arable farmers in complying with Dutch legislation (MINAS). Nitrogen Surplus is quantifiable, appealing and easy to interpret, but lacks scientific soundness or a good relationship with groundwater quality. Nitrogen Use Efficiency is sensitive to changes in management, while Residual Mineral Soil Nitrogen is appealing and cheap, but has difficulties in scaling. Groundwater Nitrate Concentration lacks clear rules for sampling, is labor consuming, expensive and mainly used in combination with other indicators. AEIs enhanced improvements in N management by facilitating (i) definition of project goals, (ii) design of desired systems, (iii) evaluation of applied systems and (iv) improving effective communication. AEI applications in other countries show a similar pattern as found in The Netherlands. Limitations to AEI application relate to inconsistencies between different indicators, heterogeneity of soil characteristics and linkages of N, carbon and water management. AEIs should be applied in an integrated evaluation, at a scale that reflects the farm's spatial variability. Simple AEIs like Nitrogen Surplus should be supported by other indicators and/or model calculations. The paper concludes that AEIs proved their value in design, implementation and testing of farming systems, but they should be used with care, always keeping in mind that indicators are simplifications of complex and variable processes.     

Importance of information on tillage practices in the modelling of environmental processes and in the use of environmental indicators

Tillage has been and will always be integral to crop production. Tillage can result in the degradation of soil, water, and air quality. Of all farm management practices, tillage may have the greatest impact on the environment. A wide variety of tillage equipment, practices and systems are available to farmers, providing opportunities to enhance environmental performance. These opportunities have made tillage a popular focus of environmental policies and programs such as environmental indicators for agriculture. This paper provides a very brief examination of the role of tillage in crop production, its effect on biophysical processes and, therefore, its impact on the environment. Models of biophysical processes are briefly examined to demonstrate the importance of tillage relative to other farm management practices and to demonstrate the detail of tillage data that these models can demand. The focus of this paper is an examination of the use of information on tillage in Canada's agri-environmental indicators initiative, National Agri-environmental Health Analysis and Reporting Program (NAHARP). Information on tillage is required for several of the indicators in NAHARP. The type of data used, its source, and its quality are discussed. Recommendations regarding the collection of tillage data and use of tillage information are presented.     

Principles and processes for effecting change in environmental management in New Zealand

In New Zealand environmental management is essentially the responsibility of land managers. Management decisions affect both production/productivity and the environment. However, responsibility for ensuring positive environmental outcomes falls on both local (Regional) and Central Government, and both they and international agencies such as the OECD would wish to monitor and report on changes. In terms of policy, strong links have been established via Central and Regional Government to land managers. Consumers in the market place are also, increasingly, requiring responsibility for positive environmental outcomes of those who purchase and process primary products. Strong links for responsibility have been established between our international markets and processing businesses and there is a noticeable strengthening of the links from the processors to the land manager/producer. In New Zealand a range of initiatives has been developed and implemented over recent times, whereby land managers are taking increasing responsibility for accounting for the environmental outcomes of their production activities. The range covers the spectrum from voluntary to compulsory (e.g., in order to meet market requirements) and from those initiated by customers to processor and/or producer initiatives. This paper follows the evolution of the principles that drove the predominant activities of the period and the processes that initiated the changes in environmental management. As the focus of agriculturalists changed from pioneering in a new world, to establishing a production base, to economic reality, and finally to environmental responsibility, the processes of extension adapted to meet the new challenge.