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771.
随着经济全球化、城市化进程的加剧,城市生态的规划建设对社会经济发展起着至关重要的作用。从可持续发展视域探讨当前城市规划建设中存在的由规划滞后、规划重复、规划片面、执法不严等造成的城市规划环境污染、资源浪费和生态破坏的问题,提出构建城市生态规划的现实必然性和基本原则,从强化机制、转变观念、以人为本、健全法制、合理规划等角度探讨可持续发展视阈下城市生态规划的途径。 相似文献
772.
济南市水资源主要存在着地下水限量开采、地表水严重不足、客水利用受到制约等问题。以济南市创建水利部水生态文明城市为背景,研究济南市水生态文明城市建设与产业布局优化,分析了济南市产业布局不合理给水资源保护和利用带来的严峻挑战,提出了以济南市水生态保护为目标的产业优化布局方案,建议大力发展水生态文明城市建设相关产业。 相似文献
773.
A. Michael S. Sheer Michael W. Nemeth Daniel P. Sheer Megan Van Ham Michael Kelly David Hill Samuel D. Lebherz 《Journal of the American Water Resources Association》2013,49(3):654-668
The Bow River Basin is a cornerstone of Alberta's development. In 2010, stakeholders representing interests from agriculture, municipalities, environment, and more formed the Bow River Project Research Consortium to help determine the potential for improving the operations in the basin. At present, upstream reservoirs are operated primarily for hydropower, whereas downstream reservoirs are operated for irrigation. Through Collaborative Modeling for Decision Support the stakeholders were able to develop a new method for operating the system that would dramatically improve environmental performance. The main components of the new operating strategy called for: purchase or setting aside of a small amount of storage volume in the power reservoirs; a set of rules for releases from that storage; an agreement by the major irrigation districts with the largest water licenses to utilize their ability to shift deliveries to and from their large offstream storage reservoirs to allow for increased instream flows, and to allow junior water license holders (mainly municipal and industrial supplies) an uninterrupted water supply; limitations of reservoir fluctuations to improve inreservoir habitat for fisheries; and increased minimum flows throughout the system leading to improved environmental outcomes. Costs of this strategy were minimal, impacts on power revenue were estimated at <US$2 million/yr on average. Compensatory arrangements should be possible. 相似文献
774.
An efficient method for prediction in the capture of SO2 from flue gas by imidazolium ionic liquids was reported, where the concentration of SO2 is 2000 ppm. On the basis of quantitative calculations through a combination of Langmuir simulation, theoretical calculation and quantum chemical method, SO2 absorption and desorption performance from flue gas by twelve kinds of imidazolium ionic liquids with different anions were designed and predicted. Then, among them, five kinds of imidazolium ionic liquids were chosen and prepared to investigate their behavior of SO2 absorption capacity, desorption residue, and available absorption capacity. The results indicated that the experimental values were in good agreement with the predicted values. Thus, an ideal ionic liquid [Emim][Tetz] was obtained through the predictive method for the capture of SO2 of 2000 ppm, which showed high available absorption capacity of 0.24 g SO2 per g ionic liquid and excellent reversibility. 相似文献
775.
南京市快速城市化时期城市用地优化评价实证研究 总被引:1,自引:0,他引:1
我国已经进入快速城市化的关键时期。城市用地需求激增,城市空间变化剧烈。按照科学发展观的时代要求,正确评价城市土地的利用水平,促进区域城市的健康和谐发展,具有十分重要的意义。以南京市为例,总结了城市用地建设中存在的城乡失衡、耕地危机、功能削弱、效率降低等主要问题,并尝试建立土地利用优化评价模型,以综合判断在快速城市化阶段城市用地的集约化程度。通过对南京市的实证分析可见,在城市的迅速扩张中,城市用地的确存在集约水平波动的现象,而且不同指标呈现差异化发展趋势。21世纪的城市土地利用,由粗放到集约、由重量到重质、由紊乱到有序是必然选择。 相似文献
776.
777.
M. Karamouz B. Zahraie Sh. Araghi‐Nejhad M. Shahsavari S. Torabi 《Journal of the American Water Resources Association》2001,37(5):1301-1311
ABSTRACT: In this paper, a system approach to water resources development in Tehran Metropolitan Area, with its complex system of water supply and demands, is discussed. Water resources in this region include water storage in the Lar, Latyan, and Karaj reservoirs, the Tehran aquifer, as well as water discharge in local rivers and in drainage channels (mainly supplied by urban runoff and wastewater). This study consists of three phases of long‐term water resources planning and management in the Tehran metropolitan area. In each phase, a different level of details among different components of the system is considered. In the first phase, optimal operating policies for Tehran reservoirs and a decision support system are developed. In the second phase, interactions between surface and ground water resources as well as surface runoffs and wastewater disposal in different subareas are investigated. The water table fluctuations as a result of implementing sewerage collection project was also simulated. In the last phase, long‐term scenarios for water resources and agricultural development in the Southern part of Tehran are defined, and the effects of each scenario on the quality and quantity of surface and ground water resources are studied. 相似文献
778.
城市污水处理厂运行管理优化方案 总被引:4,自引:0,他引:4
针对城市污水处理工程建设中存在的问题,分析了影响其运转率的三大主要因素,工程系统,运营费用及监控体制,对其运营管理中的替代方案进行了探讨,提出了实行污水厂企业化管理,建立宏观环境统一管理制度的措施建议。 相似文献
779.
根据已设环境空气监测点近5年来NO2和TSP2个项目的监测结果,得出现有监测点的日均值的相对偏差小于15%,并用F检验和t检验法对已设监测点5年来的大气监测结果进行方差和显著性差异检验,结果表明西双版纳州环境监测站提出的环境空气监测点位设置是合理的,无需调整和优化。 相似文献
780.
公路建设中水土流失影响及防治措施 总被引:4,自引:0,他引:4
公路建设中造成的水土流失越来越严重,水土流失范围呈线状,常常跨越多个流域和地貌类型,因此影响范围较广,且在公路的不同部位水土流失的程度不同,影响期限不同。在实际调查的基础上分析公路建设中水土流失的原因,并提出计算方法及一般性防护措施。 相似文献