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951.
污染物排放总量监测存在问题和对策 总被引:3,自引:1,他引:2
指出了目前总量监测中存在问题,如技术规范不够完善、监测能力和人员素质难以满足变化的生产工况、企业的配合不到位以及环评预测总量与实际情况出入太大,且不合理等。提出,应尽快制定和完善相关监测技术规范;加强在线监测监控体系的建设;加强监测人员自身专业素质的建设,以提高总量监测质量,更好地为环境管理服务。 相似文献
952.
In this study, an interval-fuzzy two-stage chance-constrained integer programming (IFTCIP) method is developed for supporting
environmental management under uncertainty. The IFTCIP improves upon the existing interval, fuzzy, and two-stage programming
approaches by allowing uncertainties expressed as probability distributions, fuzzy sets, and discrete intervals to be directly
incorporated within a general mixed integer linear programming framework. It has advantages in uncertainty reflection, policy
investigation, risk assessment, and capacity-expansion analysis in comparison to the other optimization methods. Moreover,
it can help examine the risk of violating system constraints and the associated consequences. The developed method is applied
to the planning for facility expansion and waste-flow allocation within a municipal solid waste management system. Violations
of capacity constraints are allowed under a range of significance levels, which reflects tradeoffs between the system cost
and the constraint-violation risk. The results indicate that reasonable solutions for both binary and continuous variables
have been generated under different risk levels. They are useful for generating desired decision alternatives with minimized
system cost and constraint-violation risk under various environmental, economic, and system-reliability conditions. Generally,
willingness to take a higher risk of constraint violation will guarantee a lower system cost; a strong desire to acquire a
lower risk will run into a higher system cost. 相似文献
953.
Mixed-integer linear programs are proposed for siting development and conservation areas in watersheds, addressing economic
objectives (development perimeter and proximity) and ecological objectives. Links between watershed hydrology and ecology
need not be well defined. Parameters for the linear programs are obtained from linearization of the SWAT hydrologic model. 相似文献
954.
“十二五”新疆环境监测能力建设之展望 总被引:1,自引:1,他引:0
依据全疆当前环境监测体系能力建设现状,从监测机构发展和监测网络能力发展的角度上较深刻分析了当前全疆环境监测体系存在的主要问题,提出了“十二五”新疆环境监测能力建设的设想和展望,共同行参考。 相似文献
955.
A Global Model Tracking Water, Nitrogen, and Land Inputs and Virtual Transfers from Industrialized Meat Production and Trade 总被引:1,自引:0,他引:1
Marshall Burke Kirsten Oleson Ellen McCullough Joanne Gaskell 《Environmental Modeling and Assessment》2009,14(2):179-193
Rising populations and incomes throughout the world have boosted meat demand by over 75% in the last 20years, intensifying
pressures on production systems and the natural resources to which they are linked. As a growing proportion of global meat
production is traded, the environmental impacts of production become increasingly separated from where the meat is consumed.
In this paper, we quantify the use of three important resources associated with industrial livestock production and trade—water,
land, and nitrogen—using a country-specific model that combines trade, agronomic, biogeochemical, and hydrological data. Our
model focuses on pigs and chickens, as these animals are raised predominantly in intensive systems using concentrated, compound
feeds. The results describe the geographical patterns of environmental resource use due to meat production, trade, and consumption.
We show that US feed, animal, and meat destined for export require almost as much nitrogen and land, and 20% more water, than
products destined for domestic consumption. Model results also demonstrate that among various production factors, improvements
in crop yields and animal feed conversion efficiencies result in the most significant reductions in environmental harm. By
explicitly tracking the externalities of meat production, we hope to bolster suppliers’ accountability and provide better
information to meat consumers.
相似文献
Kirsten OlesonEmail: |
956.
介绍了在环境监测分析中精确配制一定浓度标准溶液的快速方法。利用双三角解析法称量标准物质和配制标准溶液,实验过程快速、准确。在环境监测分析应用中取得较好效果,不确定度无显著差异。 相似文献
957.
958.
Managing the integrity of tailings infrastructure is an important aspect of handling mine tailings. Unfortunately, little
research is directed towards its efficient modeling. This paper presents salient aspects of tailings management. It proposes
an integrated geographic information systems (GIS)-based conceptual model for efficient handling of these aspects. The paper
also discusses the various integrated modules and comments on the systematic implementation of the model to achieve desired
results. The modules include: structural integrity management (SIM), release impact assessment (RIA), and hazardous risk assessment
and control (HRAC). 相似文献
959.
2008年我国环境保护投资总体特征分析 总被引:1,自引:1,他引:0
立足于环保投资数据库,从投资构成、空间分布和行业分布3个方面对我国环保投资进行综合分析。2008年,全国环保投资增幅持续保持较快增长,环保投资弹性系数为1.9,环保投资增速大大超过经济增速,"三同时"项目成为拉动环保投资的主要驱动力。引入了环保投资平衡度的概念,在此基础上对各地区环保投资的合理性进行了初步分析。重点行业环保投资方面,工业治污设施运行费用远远大于同期固定资产投资,一定程度上说明了应对治污运行费用来源给予充分重视,采取措施确保稳定可靠的资金渠道。 相似文献
960.
环境监测预警体系只有依靠计算机信息系统才能发挥其作用,根据预警体系的特点、内容以及要实现的功能,论述了信息系统硬件建设和软件建设的基本要求、系统的组成和系统实现的方法。 相似文献