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51.
本文从生态学角度对可持续发展理论进行了思考。指出生态危机是可持续发展产生的基本背景;生态学中许多基本理论,如协调、适应、稳定、有序、循环再生及生态系统理论等,是可持续发展不断完善的理论基础;包括生态规划、生态技术与生态管理在内的广义生态工程,是实现可持续发展的有效途径 相似文献
52.
S. Andronopoulos D. Grigoriadis A. Robins A. Venetsanos S. Rafailidis J.G. Bartzis 《Environmental Fluid Mechanics》2001,1(4):415-440
The strong fluctuating component in the measured concentration time series of a dispersing gaseous pollutant in the atmospheric boundary layer, and the hazard level associated to short-term concentration levels, demonstrate the necessity of calculating the magnitude of turbulent fluctuations of concentration using computational simulation models. Moreover the computation of concentration fluctuations in cases of dispersion in realistic situations, such as built-up areas or street canyons, is of special practical interest for hazard assessment purposes. In this paper, the formulation and evaluation of a model for concentration fluctuations, based on a transport equation, are presented. The model is applicable in cases of complex geometry. It is included in the framework of a computational code, developed for simulating the dispersion of buoyant pollutants over complex geometries. The experimental data used for the model evaluation concerned the dispersion of a passive gas in a street canyon between 4 identical rectangular buildings performed in a wind tunnel. The experimental concentration fluctuations data have been derived from measured high frequency concentrations. The concentration fluctuations model is evaluated by comparing the model's predictions with the observations in the form of scatter plots, quantile-quantile plots, contour plots and statistical indices as the fractional bias, the geometrical mean variance and the factor-of-two percentage. From the above comparisons it is concluded that the overall model performance in the present complex geometry case is satisfactory. The discrepancies between model predictions and observations are attributed to inaccuracies in prescribing the actual wind tunnel boundary conditions to the computational code. 相似文献
53.
飞信通讯手段在突发环境污染事件处置时的应用 总被引:1,自引:0,他引:1
对现有移动通讯方式在突发环境污染事件中的应用进行了比较。通过实例,简述了飞信作为突发环境污染事件应急处置时通讯方式的应用。结果表明,飞信综合了一对一、多对多的语音和图文信息传输方式,在技术资料支持和监测结果通报方面具有明显的实用价值,配合防爆型对讲机,可以满足应对突发环境污染事件时对通讯的要求。 相似文献
54.
Environmental impact assessment of a proposed info-tech complex in East Calcutta wetlands 总被引:1,自引:0,他引:1
An info-tech complex is proposed for 286 acres (116 ha) of land within the East Calcutta wetlands. The proposed site is 15 km east of Kolkata city and only 8 km south of Dum Dum airport. The site is vacant, with pockets of agricultural land and a few degrading water-logged areas. In order to assess the likely impact of the proposed development on the environment, a rapid environmental impact assessment of an area of 10 km radius from the centre of the project site was carried out. The present status of the environment with respect to ambient air, surface water, groundwater, soil, landuse, noise, and socio-economics of the core and buffer zone has been documented and correlated with 24 project activities during construction, development and operational phases. The frequency of adverse impacts is greater than that of beneficial impacts. Out of the total adverse impacts 20 are short term, reversible and have a low magnitude. The total impact score for the proposed project is (–)468.75 and as per the Assessment Value Index Scale the environmental impact of the proposed project activities is no appreciable impact. But there are certain sectors where the environment will be adversely impacted. Therefore, appropriate measures have been suggested to ameliorate the adverse impacts. It is envisaged that if these measures are implemented then there will be an improvement in the quality of the environment, as well as life, by 687.5 units. 相似文献
55.
从二维空间的角度出发,提出了系统的结构特征;联系紧密和联系松散;复杂式相互作用和直线式相互作用的概念及其特点,并探讨了系统结构特征在系统事故致因中的应用分析。 相似文献
56.
基于洪水灾害快速评估的承灾体易损性信息管理系统 总被引:5,自引:0,他引:5
洪水灾害易损性信息管理系统是为了开展洪水灾害快速评估,对不同洪水灾害流域和同一洪水灾害流域中的不同地区、不同承灾体(财产分类)、不同致灾因子(水深和历时等)条件,以财产的损失率为核心的综合信息管理系统。本文介绍了洪水灾害易损性信息管理系统的开发与设计的基本原理,阐述了系统的总体结构框架和功能模块划分,并且在系统数据流程图的基础上,对损失率数据库等几个重要的模块进行了详细的分析与设计,给出了系统的部分运行结果。本系统在与GIS、遥感等空间技术结合后,能够高效地完成各种洪水灾害损失的快速评估与预测分析工作,同时,本系统亦可独立作为对区域洪水灾害易损性研究的数据基础和理论支撑。 相似文献
57.
A “finding of no significant impact” (FONSI) resulting from an environmental assessment (EA) was reported by the US Army in
June 1986 for the construction and utilization of a multipurpose range complex (MPRC) at the Pohakuloa Training Area, Hawaii.
There was little public response, and the US Fish and Wildlife Service and state agencies were consulted and had few comments
concerning the results of the botanical surveys used in the assessment. Construction of the $24 million project was begun
in 1988. Near the end of construction in 1989 a lawsuit was filed to halt construction because an environmental impact statement
(EIS) had not been done for the project, and the plaintiff thought that significant damage had occurred to several unusual
ecosystems. Judgment was against the plaintiff and construction continued. An appeal was filed with the 9th Circuit Court.
As MPRC construction was nearly complete, and on advice of Department of Justice lawyers, the Department of Army agreed to
settle out of court. The settlement in part called for: (1) the plaintiff to drop the appeal and allow construction to be
completed as scheduled, and (2) the Department of Army to prepare an EIS for the operation of the MPRC. A subsequent botanical
survey for the EIS discovered one endangered plant species, four category 1 candidate plant species (taxa with sufficient
data to support listing as endangered or threatened), three category 2 candidate plant species (taxa with some evidence of
vulnerability but insufficient data to support listing at this time), one category 3a species (presumably extinct taxa), and
possibly three undescribed species growing within the MPRC boundary. The MPRC case study is an excellent example of why the
National Environmental Policy Act (NEPA) must be modified to require in-depth and thorough environmental surveys. 相似文献
58.
Daniel Maxwell 《Disasters》2007,31(S1):S25-S39
Food aid is a key component of a humanitarian response but its use in other programming contexts is subject to numerous criticisms. Even in humanitarian emergencies food aid is often late, unreliable and out of proportion to other elements of the response. Three major factors will shape the future of food aid. First, mechanisms of food aid governance are being reviewed and may undergo major changes—particularly the Food Aid Convention now that hopes have diminished for an Agreement on Agriculture at the World Trade Organisation. The second significant factor is donor agency trends. Overall levels of food aid have dropped fairly steadily in recent decades and there are several discernible trends in resource allocation, procurement and the use of food aid. The third factor is an emerging body of best practice that will define acceptable standards of food aid programming in the future. 相似文献
59.
60.
中和-络合萃取-双极膜电渗析处理金刚烷胺制药废水 总被引:1,自引:0,他引:1
采用中和沉淀-络合萃取-双极膜电渗析组合工艺协同处理金刚烷胺制药胺化废水与溴化废水.结果表明,通过胺化废水与溴化废水的中和反应,可以大幅消减废水中溶解性固体和有机污染物,避免后续萃取过程中的乳化现象.在pH值为8.0、油/水相比为1∶1的条件下,P204∶正辛醇=3∶2的复配萃取剂对废水中TOC和TN的萃取效率分别为56.9%和20.6%,金刚烷胺及其衍生物几乎被完全萃取.以2.0 mol·L-1的HCl溶液为反萃取剂,可以将47.5%的金刚烷胺从负载有机相中反萃分离,再生后的萃取剂可以多次重复使用.对萃余液采用双极膜电渗析进行处理,可以去除64.2%的无机盐和部分有机物,同时还能回收到较高浓度的酸,但由于氢离子的渗漏难以回收高浓度的碱. 相似文献