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Guangzhou has ambitions to build itself into a world class metropolis by 2010. Sustainable development is the only way to achieve this magnificent goal. Based on the ecological perspective of sustainable development and the principles of ecosystem integrity, this paper develops an approach for evaluation of sustainable development in Guangzhou between 1986 and 1995. A hierarchical evaluation system of four tiers of sustainability indicators was established. Using the method of fuzzy multistage synthetic evaluation, sustainability development level index, QIx, was calculated for the indicators at the B, C, D, and E tiers. Development stages were identified based on these index values. The coordination degree among the economic, social, and natural subsystems was also computed. Further, an overall sustainability index for each year was computed by combining the development level index and the coordination degree. It was found that the urban ecosystem in Guangzhou had generally become more sustainable, in spite of fluctuations in coordination degree. The development level index of the economic subsystem has surpassed that of social and natural subsystems since 1995. Appropriate measures must be taken to ensure coordinated development among the subsystems for the purpose of sustainable development. 相似文献
203.
Brian G. Field Brian G. Field J. N.R. Jeffers R. J. Livingston Jonathan Cowie 《国际发展与全球生态学杂志》2013,20(1):85-90
The aim of sustainable development is to balance social, economic, and environmental needs. In order to justify the decisions they make, stakeholders must quantify the different impacts found in the operations and developments of companies and/or projects throughout their life cycle. However, as some areas are subjective in nature, the quantification process of the different impacts and the assessment of sustainable development performance become arduous tasks of development, validation, and application of scientific and empirical methods with the intrinsic objective of finding an agreement among the involved parties (i.e., stakeholders). Several environmental and sustainability assessment tools, instruments, processes, and methodologies have been developed; rating systems stand out and have gained attention and credibility, as demonstrated by the vast number of certified projects around the world and the widely-known usefulness and advantages of their application. The Wa-Pa-Su project sustainability rating system presents an integrated approach to sustainability assessment by integrating three distinctive areas of knowledge: (1) sustainable development theory and fundamentals supports the ultimate goal of the rating system, which is to contribute to sustainability, with the aim of finding a path to balance social, economic, and environmental needs; (2) continual performance improvement becomes essential due to the duration of the projects, as it is critical to allow organizations or projects to improve performance over time; and (3) multi-criteria decision analysis assists with the assessment process through stakeholder engagement and participation, and the design and implementation of a criteria weighting system. 相似文献
204.
China has the fifth largest forest area in the world and any change in China's forestry development will have inevitable impacts on global ecological sustainability. China has undergone excessive logging of natural forests and also made tremendous efforts in afforestation during the past half century. China's forestry is now going through a variety of transitions and several forestry programs have been implemented to drive forestry transitions. The goal of these actions is to protect ecological services of forests and sustain China's forestry development. These forestry programs are spatially sophisticated and cannot be successfully implemented without accurate and transparent forest/forestry information. A variety of digital technologies, including forest modeling, remote sensing, geographic information systems, global positioning systems, and visualization, have been applied in handling diverse information in China's forestry. Digital forestry is not just a theoretical concept in China. Our digital forestry experience in northeast China suggests that digital technology is both usable and useful in China's forestry development. Digital technology is playing an important interactive role in China's top-down forestry administration system. The analog-to-digital transition in technology is expected to lead to the success of forestry programs and forestry transitions in China. 相似文献
205.
从添加秸秆进行堆肥处理的污泥中采集样品,通过富集培养和刚果红平板染色法筛选分离出具有纤维素降解能力的细菌,再通过酶活力测定从中分离筛选出1株相对高活性的产纤维素酶细菌CI;通过基于16S rRNA基因序列的系统发育分析,初步确定该菌株为Devosia sp..利用单因素试验对目的菌株C1进行产纤维素酶发酵条件优化,结果表明菌株C1产纤维素酶的最佳发酵时间、培养温度、摇床转速以及最适初始pH值分别为60 h、30℃、130 r·min^-1和7.2~7.5,且在该条件下其滤纸酶(FPase)和羧甲基纤维素酶(CMCase)活力分别达23.10和54.97 U·mL^-1. 相似文献
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Chen Cheng Haodong Li Jinling Wang Hualin Wang Xuejing Yang 《Frontiers of Environmental Science & Engineering》2020,14(5):87
209.
A. M. Guerrero M. Barnes Ö. Bodin I. Chadès K. J. Davis M. S. Iftekhar C. Morgans K. A. Wilson 《Conservation biology》2020,34(3):733-742
Attempts to better understand the social context in which conservation and environmental decisions are made has led to increased interest in human social networks. To improve the use of social-network analysis in conservation, we reviewed recent studies in the literature in which such methods were applied. In our review, we looked for problems in research design and analysis that limit the utility of network analysis. Nineteen of 55 articles published from January 2016 to June 2019 exhibited at least 1 of the following problems: application of analytical methods inadequate or sensitive to incomplete network data; application of statistical approaches that ignore dependency in the network; or lack of connection between the theoretical base, research question, and choice of analytical techniques. By drawing attention to these specific areas of concern and highlighting research frontiers and challenges, including causality, network dynamics, and new approaches, we responded to calls for increasing the rigorous application of social science in conservation. 相似文献
210.
有机磷酸酯(OPEs)是一类重要的有机磷阻燃剂,近些年逐渐取代了溴代阻燃剂,广泛应用于各行各业,也因此导致在多种环境介质中有较高的暴露量和潜在风险。已有研究表明,OPEs具有一定的毒理效应,对人体及其他生物均有潜在危害。本文综述了近年来国内外OPEs的检测技术,详述了不同环境介质OPEs的前处理方法。结果表明,目前固相萃取(SPE)和固相微萃取(SPME)仍是水样前处理的主要方法;对于固体样品,加速溶剂萃取/加压液相萃取(ASE/PLE)和微波辅助萃取(MAE)应用较多;虽然大气样品仍以固体吸附剂方式为主,但已向在线一体化方向发展;而生物样品的前处理方法多与水样和固体样品方法相似;但是对于复杂环境介质中OPEs样品的前处理较为困难,方法有待改善;气相色谱-质谱联用(GC-MS)和气相色谱-氮磷检测器(GC-NPD)对弱极性和易挥发的OPEs分析效果好,而强极性和难挥发的OPEs多用液相色谱-质谱联用(LCMS);气相色谱-质谱串联(GC-MS/MS)、液相色谱-质谱串联(LC-MS/MS)和高效液相色谱-质谱串联(UPLC-MS/MS)等对多种复杂的环境介质中的OPEs均有较好的检测分析效果,但并未普及。最后,对OPEs分析测试方法的发展趋势提出了展望。 相似文献