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221.
222.
Testing genuine savings as a forward-looking indicator of future well-being over the (very) long-run
David Greasley Nick Hanley Jan Kunnas Eoin McLaughlin Les Oxley Paul Warde 《Journal of Environmental Economics and Management》2014
Genuine Savings (GS) have been much used in recent years as an indicator of a country's sustainability. According to some theorists (e.g. Arrow et al., 2012), under certain conditions a country with a positive level of GS should experience non-declining future utility, given the assumption of unlimited substitutability among all forms of capital (sometimes called “weak” sustainability). This paper reports the first very long-run tests of GS (also called comprehensive investment or adjusted net savings) as a forward-looking indicator of future well-being. We assemble data for British capital back to 1765, and construct several net investment measures which are used as indicators of two alternative measures of future well-being: consumption per capita and real wages. An allowance for a “value of time” due to exogenous technological progress is included in some GS measures, and we demonstrate the importance of this measure and the choice of discount rate over the very long-run. On the whole, our results do not reject the postulated relationship between GS and future well-being, and show GS can be a forward looking indicator of future well-being for periods of up to 100 years. 相似文献
223.
This article demonstrates why it is necessary to have the restoration of marine coastal ecosystem health as a new goal for
integrated catchment management in the coastal area of Tolo Harbor. The present goal of integrated catchment management (ICM)
in the Tolo Harbor is based on water quality objectives. The performance of the ICM plan, the Tolo Harbor Action Plan (THAP),
was evaluated using marine coastal ecosystem health indicators including both stress and response indicators. Since the implementation
of THAP in 1988, some significant reductions in pollution loading have been observed: reduction of 83% of biological oxygen
demand load and 82% of total nitrogen between 1988 and 1999. There has also been an improvement in the health of Tolo Harbor’s
marine coastal ecosystem as evidenced by trends in physical, chemical, and biological indicators, although reverse fluctuations
in some periods exist. However, such improvement can only be considered as the first sign of complete ecosystem health restoration,
because ecosystem health covers not only physical, chemical, and biological aspects of an ecosystem, but also ecosystem service
functions. The findings support the need to take the restoration and protection of marine coastal ecosystem health as a new
goal rather than using water quality objectives. Steps necessary to further improve Tolo Harbor’s marine coastal ecosystem
health are also discussed. 相似文献
224.
水环境综合整治方案的优化决策必须考虑社会、经济、技术、环境等多种指标,在这些指标中既有已知信息,又有未知或未确知的灰色信息。因此,水环境综合整治方案的优化属于灰色多目标优化问题。本文利用灰色多目标优化模型,选取六个优化指标,对宣州市水环境综合整治的五种可行方案进行了优化决策,得到了符合当地社会、经济、技术和环境状况的优化方案。研究表明,该模型原理简单、计算简便、结果可靠,是一种很有实用价值的多方案优化模型。 相似文献
225.
以1987~1990年海湾环境调查资料为基础,探讨了位起东部北黄海的青堆子湾(东经123°25′05E,北纬39°45′50″N).,西止渤海的锦州湾(东经121°04′55″E,北纬40°47′22″N)的辽宁省共13个海湾水质、底质和生物中化学要素含量分布,得到广诸海湾污染程度是:除污染物锅外,重金属为底质>生物>水质;系统阐述了各海湾的环境质量现状及化学要素的超标情况,为今后选划各湾的适养区,治理环境污染提供了科学依据。 相似文献
226.
本文提出采用化学絮凝、沉降方法除去味精发酵醪液菌体,清液采用浓缩—连续等电点法提取谷氨酸。采用新工艺后,菌体可回收作蛋白饲料,谷氨酸提取率由现在的75%—78%提高至85%,废水量减少一半以上,采用蒸发浓缩处理,回收作有机复合肥,根本解决了味精废水污染环境的问题。 相似文献
227.
Panos G. Georgopoulos 《Water, Air, & Soil Pollution: Focus》2008,8(1):3-21
Advances in computing processing power and in availability of environmental and biological data have allowed the development
and application of comprehensive modeling systems that utilize a holistic, integrated, approach for assessing the interactions
of environmental and biological systems across multiple scales of spatiotemporal extent and biological organization. This
approach allows mechanism-based environmental health risk assessments in a person-oriented framework, which accounts for simultaneous
exposures to contaminants from multiple media, routes, and pathways. The conceptual basis and example applications of the
Modeling ENvironment for TOtal Risk (MENTOR), and the DOse–Response Information ANalysis system (DORIAN) are presented. 相似文献
228.
229.
PE管道固有较高的性价比,广泛应用在能源、燃气等工程中,但因其焊接接头质量难以检测、位置探查难度大,使PE管道的安全状况难以控制,导致泄漏等事故。基于PE管材的失效模式,参照钢质管道的检验经验,中国特种设备检测研究院研究确定了PE管道基于失效模式的全面检验关键技术,并围绕关键技术开展了多项研究,取得了一系列科研成果,如:PE管焊接质量超声相控阵动态聚焦和B扫查成像检测、探地雷达、泄漏在线检测、老化及安全评价、风险评估方法等。这些系列成果,在新疆、青海、内蒙古、宁夏等城市PE燃气管网中得到了有效应用,检验出多项安全隐患,为城市燃气的安全提供了保障,为今后全面开展PE管线检验,提供了成功经验。 相似文献
230.