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71.
As a global developing tendency, the general viewpoint has been reached in the construction of the ecocities, which has produced widespread influence in the international society. Cities must enable people to live in harmony with nature and achieve sustainable development. Although more and more cities in the world are being designed and built to the ecological ones, the construction is also theoretical questions and arduous tasks. People oriented, ecocity development requires the comprehensiv…  相似文献   
72.
Abstract

With the approach of the second water storage of the Three Gorges Project, urban migration has become a great concern. However, being influenced by economical, social or other factors, ecological problems have apparently become pressing. All these problems are exerting great impact upon the speed and quality of new city's or town's construction. By means of ecology, urban ecology, landscape ecology, human settlement science as well as the principle of sustainable development, this paper analyzes the ecological problems in urban migration, and the corresponding approaches in order to promote ecological environment construction of new cities and give an impetus to sustainable development of the whole human settlements in the Three Gorges Reservoir Region.  相似文献   
73.
温室气体N2O含量的增加对气候变化产生显著影响,针对污水处理行业N2O减排控制的发展趋势与需求,以典型污水生物处理工艺为对象,对N2O产生机理、释放特征和核算、影响因素进行了综述和分析.研究表明,污水处理厂N2O的释放主要来自生物脱氮过程的硝化阶段和反硝化阶段,不同污水处理厂的N2O释放因子和释放特征不同.DO、温度和C/N是影响N2O释放的主要因素,最后从污水处理厂工艺运行和水质调控角度提出了具有可操作性的N2O减排途径与方法.  相似文献   
74.
"生态保护红线、环境质量底线、自然资源利用上线和环境准入负面清单"(简称"三线一单")是一项重大环境管理制度创新,目前国家已经发布相关编制技术指南(试行),并在长江经济带12省市全面启动编制工作,其中划定大气环境质量底线是"三线一单"的核心内容之一。本文结合生态环境部"三线一单"试点城市编制实践,从大气环境质量底线内涵与框架、技术方法、管控措施设计等方面,提出大气环境质量底线体系与划分技术方法,以期为进一步规范"三线一单"编制技术奠定基础。  相似文献   
75.
SUMMARY

Integrated natural resources management (INRM) has to address both the livelihood goals of farmers and the ecological sustainability of agroecosystems and natural resources. Under the Ecoregional Initiative for the Humid and Sub-Humid Tropics of Asia — Ecor(1)Asia — one major set of activities has been the development of approaches, methodologies, and tools to meet the challenges of INRM research for sustainable agricultural development. Examples provided illustrate the role of these methodologies in the three main phases of knowledge development for improving INRM impact: knowledge generation, knowledge capitalization, and knowledge mobilization. The methodologies are designed for better integration across disciplines, spatial scales, and hierarchical levels of social organization. Attempts are made to quantify trade-offs between biophysical sustainability and socio-economic considerations. The case is made for using these methodologies in a more complementary manner to help bridge the topdown and bottom-up approaches in INRM. Inherent in the developing and implementing of these methodologies is the forging of partnerships and fostering linkages with multiple stakeholders, as well as using the knowledge base and integrative tools as communication platforms.  相似文献   
76.
Soils often exhibit a variety of small-scale heterogeneities such as inter-aggregate pores and voids which partition flow into separate regions. In this paper a methodological approach is discussed for characterizing the hydrological behaviour of a heterogeneous clayey–sandy soil in the presence of structural inter-aggregate pores. For the clay soil examined, it was demonstrated that, coupling the transfer function approach for analyzing BTCs and water retention data obtained with different methods from laboratory studies captures the bimodal geometry of the porous system along with the related existence of fast and slow flow paths. To be effectively and reliably applied this approach requires that the predominant effects of the soil hydrological behaviour near saturation be supported by accurate experimental data of both breakthrough curves (BTCs) and hydraulic functions for high water content values. This would allow the separation of flow phases and hence accurate identification of the processes and related parameters.  相似文献   
77.
单级序批式生物膜反应器(SBBR)多途径生物脱氮研究   总被引:2,自引:0,他引:2  
徐峥勇  杨朝晖  曾光明  王荣娟  肖勇  许朕 《环境科学》2007,28(10):2326-2331
利用传统微生物分析技术与PCR、变性梯度凝胶电泳(DGGE)等分子生物学技术相结合的方法,对单级SBBR反应器中的主要生物脱氮途径进行分析.结果表明,亚硝化-厌氧氨氧化-反硝化途径是主要的脱氮途径,通过该途径去除的NH+4-N占总去除量的65%以上;另外2条途径则分别是亚硝化-反硝化途径以及全程硝化-反硝化途径.所有途径都采取同步和分步2种方式完成,同步方式以曝气阶段的氮素亏损形式予以表现.分步方式则依靠各种脱氮微生物在曝气阶段和厌氧阶段不同的活性程度完成,亚硝酸细菌是曝气阶段的主要活性菌种,完成NH+4-N向NO-2-N的转化,而厌氧氨氧化细菌和反硝化细菌则在厌氧阶段成为优势菌种,完成完整的生物脱氮过程.  相似文献   
78.
Nowadays every piece of working equipment and tools has to comply with safety standards and laws. This study investigated multi-criteria methods for selecting working equipment in order to optimize performance and occupational safety. The multi-criteria decision-making (MDCM) method was applied to the problem of selecting optimal working equipment using four different criterion weighting approaches (direct weighting, revised Simos procedure, Fuller’s triangle and analytic hierarchy process). Groups of economic, technical and safety criteria were defined and five weighting scenarios were developed. Although the four weighting methods produced similar results, in some situations they produced different criterion weighting factors. The final output of the MCDM method was the identification of the optimal forklift in the five weighting scenarios. Although we have applied the MCDM method to a forklift selection problem, it can be applied to all sorts of working equipment in contexts where economic, technical and safety selection criteria can be identified.  相似文献   
79.
介绍了当前珠江三角洲地区公众参与环境保护的现状,并提出珠江三角洲地区公众参与环境保护的必要性和参与途径。  相似文献   
80.
AcomparativeassessmentofalternativeapproachestosustainabledevelopmentPanJiahuaInstituteofWorldEconomicsandPolitics,ChineseAca...  相似文献   
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