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471.
五溴联苯醚是一种典型的持久性有机污染物,其广泛使用对环境造成的污染以及对生物产生的毒性越来越严重,因此研究五溴联苯醚的修复技术具有重要意义.结合当前国内外的研究进展,综述了污染环境中五溴联苯醚的多种修复方法,包括物理修复、化学修复及生物修复等,并介绍了修复技术的机理及影响因素.今后发展的主要方向是寻求多种方法协同作用,以达到快速、彻底的对五溴联苯醚进行降解的效果. 相似文献
472.
由美国耶鲁大学和哥伦比亚大学合作开发的环境可持续指数(Environmental Sustainability Index,ESI)可用以衡量一个国家或地区能为其后代人保持良好环境状态的能力,也可考虑作为环境决策的基础之一。其研究处在现有环境可持续指标体系研究的国际前沿水平。本文简介了ESI的进展与内涵;阐述了2005ESI的指标设置、方法学及其改进;列举了2005ESI用于146个国家或地区环境可持续性的测试结果及其政策建议,分析了中国得分很低的原因,最后,概要评述了ESI的特点和进一步发展方向。 相似文献
473.
BEN COLLEN§ JONATHAN LOH† SARAH WHITMEE LOUISE McRAE RAJAN AMIN‡ JONATHAN E. M. BAILLIE‡ 《Conservation biology》2009,23(2):317-327
Abstract: The task of measuring the decline of global biodiversity and instituting changes to halt and reverse this downturn has been taken up in response to the Convention on Biological Diversity's 2010 target. It is an undertaking made more difficult by the complex nature of biodiversity and the consequent difficulty in accurately gauging its depletion. In the Living Planet Index, aggregated population trends among vertebrate species indicate the rate of change in the status of biodiversity, and this index can be used to address the question of whether or not the 2010 target has been achieved. We investigated the use of generalized additive models in aggregating large quantities of population trend data, evaluated potential bias that results from collation of existing trends, and explored the feasibility of disaggregating the data (e.g., geographically, taxonomically, regionally, and by thematic area). Our results show strengths in length and completeness of data, little evidence of bias toward threatened species, and the possibility of disaggregation into meaningful subsets. Limitations of the data set are still apparent, in particular the dominance of bird data and gaps in tropical-species population coverage. Population-trend data complement the longer-term, but more coarse-grained, perspectives gained by evaluating species-level extinction rates. To measure progress toward the 2010 target, indicators must be adapted and strategically supplemented with existing data to generate meaningful indicators in time. Beyond 2010, it is critical a strategy be set out for the future development of indicators that will deal with existing data gaps and that is intricately tied to the goals of future biodiversity targets. 相似文献
474.
We propose a geo-referenced framework for agricultural sustainability assessment aimed at supporting policy planning. The framework is based on Rough Set theory and (i) integrates the three pillars of sustainability; (ii) proposes an easy measurement of agricultural systems’ ability to resist over time (agricultural resilience); (iii) offers easy-to-read results; and (iv) reduces the gap between researchers’ analytical skills and decision-makers’ needs. In the paper, a part of the framework, we present essential and practical notion of Rough Set theory and a case study based on Lombardy Region (Italy). Finally, some values and lacks of the method are discussed. 相似文献
475.
Socioeconomic indicators and the survival of the tropical rainforest of cross river state of Nigeria
An internal household survey of socioeconomic indicators in the Cross River State forest communities showed that basic infrastructural
facilities such as clean water supply, adequate waste disposal system, good roads and electricity are grossly inadequate.
There is a total absence of modern family planning practices in the communities, and population is projected to increase by
44.8% between 2000 and 2015 and 85.4% between 2000 and 2025. The study revealed that about 65% of the population of the rainforest
communities consists of subsistence farmers and power chain operators, and besides the 19% of the Cross River State Tropical
High Forestry (THF) already reported to have been lost to agriculture and plantation between 1972 and 1991, about 9% was lost
between 1991 and 2000. An additional 25% of the THF will be lost by 2025, leaving only 470600 hectares (4706 km2). With 84.1% of community members having an annual income less than $300, the survival potential of the Cross River State
rainforest in the next fifty years is very low, unless an effective forest management programme is encouraged by government
in partnership with all stakeholders. 相似文献
476.
The need to include environmental criteria in the analysis of supply chains is increasingly recognized as a result both of limitations that are posed by legislation and regulations as well as of various motivations that a company may have. A decision model is proposed in this paper based on environmental performance indicators, which may support decision making in the case of supply chains in the presence of environmental considerations. The model uses a set of principles applicable to supply chains design and operation available from previous research work. 相似文献
477.
何婧婷 《安全.健康和环境》2020,(4):27-31
针对中国石化销售企业所属油库特点,以专业性、先进性、定性与定量相结合、可操作性为原则,对照国家、中国石化相关标准规范,兼顾基层特色,深入调查研究,经现场测试、多次专家研讨,构建了以落实绿色行动要求、完善污染治理设施管理、节约资源能源等13项要求为重点考核内容,由55项具体指标组成的绿色油库评价指标体系,现已正式在中国石化销售板块发布实施,为纵深推进企业绿色发展提供了科学合理的标准支撑。 相似文献
478.
This paper describes a comparative analysis of alternative methods of constructing composite indicators to measure the sustainability of the agricultural sector. The three methods employed were Principal Component Analysis, the Analytic Hierarchy Process and a Multi-Criteria technique. The comparison focused on the irrigated agriculture of the Duero basin in Spain as a case study, using a dataset of indicators previously calculated for various farm types and policy scenarios. The results enabled us to establish a hierarchy of preferred policy scenarios on the basis of the level of sustainability achieved, and show that the most recent CAP reform is the most sustainable agricultural policy scenario. By analyzing the heterogeneity of different farms types in each scenario, we can also determine the main features of the most sustainable farms in each case. The analysis demonstrates that full-time farmers with small to medium-sized farms and sowing profitable crops are the most sustainable farm types in all the policy scenarios. All of this information is useful for the support of agricultural policy design and its implementation, as we attempt to improve the sustainability of this sector. 相似文献
479.
人类健康风险的定量评估与分析 总被引:1,自引:0,他引:1
通过深入研究.将人类健康风险解析环境污染、食物安全、疾病流行和医疗保障四个方面。在建立一套评价人类健康风险指标体系的基础上。对40个样本国家进行评估。用聚类分析的方法.将40个国家分为四类,在对每一类国家的人类健康风险特点进行对比发现,在同等经济发展水平下,中国的人类健康风险相对较高。通过分析人类健康风险与经济发展水平的关系得出,人均GNI 1000,3000美元是国家经济发展的关键时期。同样也是改善人类健康状况的关键时期,这一时期国家要高度重视改善人类健康状况。 相似文献
480.
Michael R. Meador 《Journal of the American Water Resources Association》2013,49(2):253-263
Abstract: Relationships between nutrient concentrations and fish nutrient tolerance were assessed relative to established nutrient criteria. Fish community, nitrate plus nitrite (nitrate), and total phosphorus (TP) data were collected during summer low‐flow periods in 2003 and 2004 at stream sites along a nutrient‐enrichment gradient in an agricultural basin in Indiana and Ohio and an urban basin in the Atlanta, Georgia, area. Tolerance indicator values for nitrate and TP were assigned for each species and averaged separately for fish communities at each site (TIVo). Models were used to predict fish species expected to occur at a site under minimally disturbed conditions and average tolerance indicator values were determined for nitrate and TP separately for expected communities (TIVe). In both areas, tolerance scores (TIVo/TIVe) for nitrate increased significantly with increased nitrate concentrations whereas no significant relationships were detected between TP tolerance scores and TP concentrations. A 0% increase in the tolerance score (TIVo/TIVe = 1) for nitrate corresponded to a nitrate concentration of 0.19 mg/l (compared with a USEPA summer nitrate criterion of 0.17 mg/l) in the urban area and 0.31 mg/l (compared with a USEPA summer nitrate criterion of 0.86 mg/l) in the agricultural area. Fish nutrient tolerance values offer the ability to evaluate nutrient enrichment based on a quantitative approach that can provide insights into biologically relevant nutrient criteria. 相似文献