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211.
A FRAMEWORK FOR PROCESS INDICATORS TO MONITOR
FOR SUSTAINABLE DEVELOPMENT: PRACTICE TO AN URBAN WATER SYSTEM 总被引:2,自引:0,他引:2
Although very often used, the concept of sustainable development has not yet been perceived pragmatically. Due to its process
nature, in this paper, we argue that sustainable development is a process in which the essential feedback loops, or Viability Loops as we name them, in the system in question are kept healthy and functional. This process deals with evolutionary changes
with the end point not known in advance. According to this perception, measurement of sustainable development does not make
sense. Rather, we should look for the process indicators to monitor systems for sustainable development. The purpose of the
paper is to develop a methodology to deal with monitoring systems for sustainable development and its practice in an urban
water system. Using a system dynamics approach, the paper adopts a systemic monitoring framework based on the idea of Viability Loops to define process indicators to monitor systems for sustainable development. To illustrate the application of the framework,
its practice in the urban water system of Tehran, the capital of Iran, is provided as an example. The example of the urban
water supply system of Tehran is given as a case study, albeit with some unavailable data. Here, four typical viability loops
are discussed. The results of this application show that the flows of informative signals are lacking. Adopting the process
indicators, we can see the gaps between the public perceptions of water abundance, the costs of water provision and energy
utilizations, and what is going on in the reality are getting wider. That indicates that the viability loops are not functional
enough to produce effective changes to offset the reinforcing mechanisms. The sustainable development of the system is impaired
due to the persistence of those reinforcing mechanisms. 相似文献
212.
Trace element analysis for five elements namely, Ba, Sr, Mn, Cr and Cd was carried out on both ash weight and dry weight basis for mine water and coconut water from Mangampeta barite area. The concentration of trace elements is strikingly different in the coconut water when compared with that of mine water. The coconut plant has the ability to control the presence of certain inorganic elements in its water, whatever be the amount of those elements present in irrigation water. Further, biogeochemical studies of coconut water may be of considerable importance in balneology. 相似文献
213.
This paper proposes the concept of cumulative eco-intensity with which environmental or sustainability indicators are related to the added value of economic activities. The intensities are passed on recursively from supplier to supplier and thus make it possible to include upstream and downstream effects along the supply and waste disposal chain. The process is applied to whole companies and (by contrast with LCA) not to individual products. At comparatively low expenditure for the individual companies, it allows vertical comparisons along the value-adding chain and horizontal comparisons among companies or production locations. This provides a decision-making aid for a company seeking to fulfil its ecological or sustainability responsibility in the entire production and supply chains. 相似文献
214.
Borrego C Monteiro A Ferreira J Miranda AI Costa AM Carvalho AC Lopes M 《Environment international》2008,34(5):613-620
The main objectives of this work focus, firstly, on a review of the current existent methodologies to estimate air quality modelling uncertainty, and, secondly, in the preparation of guidelines for modelling uncertainty estimation, which can be used by local and regional authorities responsible for air quality management. From the application exercise, it was concluded that it is possible to define a subset of statistical parameters able to reproduce the general uncertainties estimation. Concerning the quality indicators defined by EU directives, the results show that the legislated uncertainty estimation measures are ambiguous and inadequate in several aspects, mainly in what concerns the error measures for hourly and daily indicators based on the highest observed concentration. A relative error at the percentile correspondent to the allowed number of exceedances of the limit value was suggested and tested, showing that is a more robust and appropriate parameter for model performance evaluation. 相似文献
215.
Beaulant AL Perron G Kleinpeter J Weber C Ranchin T Wald L 《Environment international》2008,34(5):599-605
Maps of pollutants concentration are usually generated by means of interpolation and extrapolation methods. The quality of the results depends mainly of the number of permanent or temporary measuring stations. This paper deals with a method for the virtual densification of the network of stations. The method creates "virtual measuring stations". It aims at improving the quality of interpolation by increasing the number of data on pollutant concentration. The virtual stations are determined by the means of a classification method applied to each pixel of the area under concern. Discriminating elements are pollutants emission classes, land cover types, urban morphological indicators created to this purpose and distance to major roads. A first implementation was made for particulate matter (PM) for the city of Strasbourg (France) using thin-plates spline interpolation method in Arcview 9 GIS. The relative Root Mean Square Error decreases from 49% for five input stations down to 15% for the virtual stations. 相似文献
216.
真实储蓄率与可持续发展研究 总被引:1,自引:0,他引:1
随着全球经济高速发展,地球上的环境却持续恶化,由于经济与环境相互牵制又相互促进,如何实现经济不断增长并能有效保护环境,即实现“可持续发展”成为目前大家普遍关注的问题,本文分析了真实储蓄概念的提出,认为真实储蓄率是基于传统国民经济核算以上两方面的缺陷而提出的。并进一步解释了真实储蓄率的概念,绿色GDP和真实储蓄的关系,及真实储蓄,可持续收入(SI)及生态国民生产净值(EDP),可持续经济福利指标(ISEW)和真实发展指数(GPI)几种货币化的可持续发展指标的相互关系,认为真实储蓄是一种比较实用的衡量可持续发展的综合指标。 相似文献
217.
低碳经济与“两型社会”的相关性及指标研究 总被引:2,自引:0,他引:2
能源和环境是本世纪紧密关联的两个最重要问题,因此发展低碳经济,建设“两型社会”是中国寻求自身进一步发展的必经之路。首先在分析低碳经济与“两型社会”理念内涵的基础上,揭示了两者的关系,它们虽然是两个独立的概念,但也存在紧密联系;其次在“两型社会”建设中融入低碳经济发展的“脱钩”指标,它和其他指标一起评价“两型社会”的建设成果,是判断“两型社会”是否成功的重要标志。本文选择的低碳经济发展的“脱钩”指标主要包括能源消耗与经济增长的“脱钩”指标以及二氧化碳排放与经济增长的“脱钩”指标。这些低碳发展评价指标不仅能够反映经济增长与资源环境变化的响应关系,还能进一步评价“两型社会”建设成果,具有深远的理论和实践意义。 相似文献
218.
不同基质上着生生物群落生态学特性比较研究 总被引:1,自引:0,他引:1
为了寻找最佳采样基质和方法,研究使用各种不同自然和人工基质对天然水体中的着生生物群落进行了采样。自然基质选取菹草、光壳钉螺和沿岸石块。人工基质采样装置由载玻片和染色架构成.使用时悬挂于河水之中。对各基质上的着生生物现存量、藻类细胞密度、着生藻类叶绿素a和着生生物干重等生态学指标进行了分析和比较.并简要分析了造成差异的原因。分析结果表明,各基质上着生藻类在种类组成上基本相似,以硅藻门、绿藻门为主。优势藻种为舟形藻属短小舟形藻、异极藻属缢缩异极藻和脆杆藻属克洛脆杆藻。不同基质上着生藻类的组成与藻类习性和细胞构造有关,与基质无关。但是不同基质也造成藻种间多样性的差异.这可能与基质表面粗糙程度、水流方向有关。附石藻类表征水体污染效果最好,所以建议采样时选取形状规则的石块为基质.最能反映着生生物群落的真实情况。 相似文献
219.
Li Li Changhong Chen Cheng Huang Haiying Huang Gangfeng Zhang Yangjun Wang Minghua Chen Hongli Wang Yiran Chen D. G. Streets Jiamo Fu 《环境科学学报(英文版)》2011,23(7):1150-1157
Ozone has become one of the most important air pollution issues around the world. This article applied both O3/(NOy-NOx) and
H2O2/HNO3 indicators to analyze the ozone sensitivity in urban and rural areas of Shanghai, with implementation of the MM5-CMAQ
modeling system in July, 2007. The meteorological parameters were obtained by using the MM5 model. A regional emission inventory
with spatial and temporal allocation based on the statistical data has been developed to provide input emission data to the MM5-CMAQ
modeling system. Results showed that the ozone concentrations in Shanghai show clear regional differences. The ozone concentration
in rural areas was much higher than that in the urban area. Two indicators showed that ozone was more sensitive to VOCs in urban
areas, while it tended to be NOx sensitive in rural areas of Shanghai. 相似文献
220.