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591.
Green Space Changes and Planning in the Capital Region of China   总被引:4,自引:0,他引:4  
Green space plays an important role in complex urban ecosystems and provides significant ecosystem services with environmental, aesthetic, recreational and economic benefits. Beijing is the capital city of China and has a large population of about 15.81 million. Construction of green spaces is an important part of sustainable development in Beijing. To attain the sustainable development of Beijing as a capital city, an international city, a historical cultural city, and a living amenity city, this article attempts to develop a comprehensive plan of green space development both at the municipal and regional levels. At the municipal level of Beijing, based on the study of green space changes, and taking physical geographic conditions and historical context into account, we propose to establish green barriers in the mountainous area, and plan a comprehensive green space pattern composed of one city, two rings, three networks, eight water areas, nine fields, and several patches in the plain area. At the regional level of the Capital Circle Region, integrating the characteristics and causes of main environmental issues, we design a macroscopic pattern—“barriers by mountains in the northwest,” “seaward open spaces in the southeast,” “grassland-forest-field-coast zones,” and “green-blue symphony”—for ecological restoration and green space construction. Finally, we discuss the principles necessary to implement green space planning considering adaptation to local conditions, composite function exploitation, interregional equity and integrated planning.  相似文献   
592.
城市人居环境的改善是经济持续发展的动力和保障,经济发展是人居环境改善的物质基础和载体.城市人居环境与经济协调发展是实现可持续发展的重要途径.以新疆沙湾县为研究对象,通过构建城镇人居环境与经济发展协调度指标评价体系,并运用主成分分析方法和协调度模型,对1999-2008年沙湾县城镇人居环境与经济协调发展水平进行了综合评价.结果表明:10年来城镇人居环境与经济发展协调程度逐渐上升,可以划分1999-2004年缓步上升和2005-2008年波动上升2个发展阶段.目前,沙湾县城镇人居环境与经济发展已到达高度协调状态,处理好两者的关系,使之更近一步达到优质协调,从而实现沙湾县经济、社会和生态环境的协调可持续发展.  相似文献   
593.
China has established the largest clean coal-fired power generation system in the world by accomplishing the technological transformation of coal-fired power plants(CFPPs) to achieve ultra-low emission. The potential for further particulate matter(PM) emission reduction to achieve near-zero emission for CFPPs has become a hotspot issue. In this study,PM emission from some ultra-low emission CFPPs adopting advanced air pollutant control technologies in China was reviewed. The results revealed tha...  相似文献   
594.
Abrupt air pollution accidents can endanger people’s health and destroy the local ecological environment. The appropriate emergency response can minimize the harmful effects of accidents and protect people’s lives and property. This paper provides an overview of the key emergency response technologies for abrupt air pollution accidents around the globe with emphasis on the major achievements that China has obtained in recent years.With decades of effort, China has made significant progress in em...  相似文献   
595.
Accurate monitoring of the atmospheric environment and its evolution are important for understanding the sources, chemical mechanisms, and transport processes of air pollution and carbon emissions in China, and for regulatory and control purposes. This study gives an overview of atmospheric environment monitoring technology and equipment in China and summarizes the major achievements obtained in recent years. China has made great progress in the development of atmospheric environment monitoring technology and equipment with decades of effort. The manufacturing level of atmospheric environment monitoring equipment and the quality of products have steadily improved, and a technical & production system that can meet the requirements of routine monitoring activities has been initiated. It is expected that domestic atmospheric environment monitoring technology and equipment will be able to meet future demands for routine monitoring activities in China and provide scientific assistance for addressing air pollution problems.  相似文献   
596.
对新季铵盐型Gemini阳离子表面活性剂CG12-3-12、生物表面活性剂鼠李糖脂Rhamnolipid、普通非离子表面活性剂TX-100以及它们的混合体系对多环芳烃菲和芘的增溶效果进行了比较研究.通过计算与比较临界胶束浓度(CMC)、摩尔增溶率(MSR)和增溶的标准自由能ΔG0s,评价了3种不同类型表面活性剂及它们的混合体系对菲和芘的增溶能力.3种表面活性剂对菲和芘的增溶性大小顺序为:CG12-3-12RhamnolipidTX-100.TX-100/CG12-3-12与TX-100/Rhamnolipid混合表面活性剂都较相对应的单一表面活性剂有更好的增溶能力,在降低表面张力效率方面都能够产生协同效应.但是两种混合溶液都不符合理想溶液的性质.TX-100/CG12-3-12系统的CMCexp相对于CMCmi有更大的负偏差.由两混合体系的吉布斯自由能ΔG0m可以看出,TX-100与鼠李糖脂比与CG12-3-12更容易形成混合胶束.TX-100/CG12-3-12与TX-100/Rhamnolipid表现出协同作用.TX-100/Rhamnolipid混合体系对菲和芘的增溶能力的提高大于TX-100/CG12-3-12混合体系.本实验研究结果可为疏水性有机物污染环境修复效果的强化提供科学依据.  相似文献   
597.
地表水环境的治理和改善受到社会、经济、环境等多方面因素的共同影响,如何合情、合理地制定地表水污染防治政策、规划,在复杂的水环境污染突发事件中及时掌握事态的发展和正确的处理处置方法是我国各级环境保护管理部门面临的一大难题。本论文以建立水质污染扩散模型为基础,结合我国地表水环境管理现状提出了一套地表水污染监控预警和应急管理体系,旨在建立废水污染源与地表水环境质量的内在联系,用科学的方法为地表水污染防治管理工作提供技术支撑。  相似文献   
598.
本文以畜禽养殖较为集中、污染问题较为突出的辽河源头区为研究区域,通过流域内畜禽污染物排放方式,污染物排放总量,总结流域内畜禽养殖污染特点,在次基础上提出切实可行的畜禽污染防治对策,为相关政策的制定提供依据。  相似文献   
599.
Biogenic elements and six phosphorus(P) fractions in surface sediments from the Changjiang Estuary and adjacent waters were determined to investigate the governing factors of these elements, and further to discuss their potential uses as paleo-environment proxies and risks of P release from sediment. Total organic carbon(TOC) and leachable organic P(Lea-OP) showed high concentrations in the estuary, Zhejiang coast and ofshore upwelling area. They came from both the Changjiang River and marine biological input.Biogenic silicon(BSi) exhibited a high concentration band between 123 and 124°E. BSi mainly came from diatom production and its concentration in the inshore area was diluted by river sediment. Total nitrogen(TN) was primarily of marine biogenic origin. Seaward decreasing trends of Fe-bound P and Al-bound P revealed their terrestrial origins. Influenced by old Huanghe sediment delivered by the Jiangsu coastal current, the maximum concentration of detrital P(Det-P) was observed in the area north of the estuary. Similar high concentrations of carbonate fluorapatite(CFA-P) and CaCO3 in the southern study area suggested marine calcium-organism sources of CFA-P. TOC, TN and non-apatite P were enriched in fine sediment, and Det-P partially exhibited coarse-grain enrichment, but BSi had no correlation with sediment grain size. Diferent sources and governing factors made biogenic elements and P species have distinct potential uses in indicating environmental conditions. Transferable P accounted for 14%-46% of total P. In an aerobic environment,there was low risk of P release from sediment, attributed to excess Fe oxides in sediments.  相似文献   
600.
CO2 capture and utilization (CCU) is an effective strategy to mitigate global warming. Absorption, adsorption and membranes are methods used for CO2 separation and capture, and various catalytic pathways have also been developed for CO2 utilization. Although widely researched and used in industry, these processes are energy-intensive and this challenge needs to be overcome. To realize further optimization, novel materials and processes are continuously being developed. New generation materials such as ionic liquids (ILs) have shown promising potential for cost-effective CO2 capture and utilization. This study reviews the current status of ILs-based solvents, adsorbents, membranes, catalysts and their hybrid processes for CO2 capture and utilization. The special properties of ILs are integrated into new materials through hybridization, which significantly improves the performance in the process of CCU.  相似文献   
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