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841.
Agricultural producer participation and spatial coordination of land use decisions are key components for enhancing the effective delivery of ecosystem services from private land. However, inducing participation in Payment for Ecosystem Services schemes for coordinating land management choices is challenging from a policy design perspective owing to transaction costs associated with participation. This paper employs a laboratory experiment to investigate the impact of such costs on participation and land use in the context of an Agglomeration Bonus (AB) scheme. The AB creates a coordination game with multiple Nash equilibria related to alternative spatially-coordinated land use patterns. The experiment varies transaction costs between two levels (high and low), which affects the risks and payoffs of coordinating on the different equilibria. Additionally, an option to communicate is implemented between neighbors arranged on a local network to facilitate spatial coordination. Results indicate a significant difference in participation and performance under high and low transaction costs, with lower uptake and performance when transaction costs are high. These effects are, however, impacted by transaction costs faced in the past. Communication improves both AB participation rates and performance with the effect being greater for participants facing high transaction costs. 相似文献
842.
Chen Demin 《中国人口.资源与环境(英文版)》2013,11(1):18-23
Abstract By analyzing the relationship between a recycling economy and sustainable development theory, this article puts forward the basic concept of a recycling economy as a dynamic economic operational model, and explains the four basic characteristics. It is stressed that the essential element of a recycling economy is the use of resources circularly. In the end, this article analyzes the phenomena of utilizing the recycling economy concept incorrectly, and sets forth a number of problems that should be noted during the process of developing a recycling economy in China. 相似文献
843.
《International Journal of Sustainable Engineering》2013,6(5):333-340
ABSTRACTThis paper quantifies construction and demolition waste (C&DW) generation rate in Indian cities using bottom-up material flow analysis approach. A dynamic model was applied to different classes of cities in India to investigate how C&DW generation rate varies across different classes of cities. The data on construction and demolition activities in different classes of cities were estimated from information reported in secondary literature. The results show that urban areas in India generated over 150 million tonnes of C&DW in 2016, and almost 50% of waste was generated in small to medium towns. The paper concludes with discussion on opportunities for recycling of C&DW and closing the material loops in Indian cities. 相似文献
844.
《International Journal of Sustainable Engineering》2013,6(4):233-239
ABSTRACTThe high-performance carbon fibres can be recycled from waste carbon fibre/epoxy resin composites by supercritical n-butanol. Recycling experiment designed by response surface method was used to investigate quantitative relation between degradation rate of epoxy resin and process parameters. Thus, the optimum process parameters could be obtained, and effects of process parameters and layers on degradation rate and mechanical performance of the recycled carbon fibres were analysed. The tensile strength of the recycled carbon fibre under the optimum process parameters was 94.53% of that of the original carbon fibre, tensile modulus was 93.57% of that of the original carbon fibre and interfacial shear strength was 90% of that of the original carbon fibre. 相似文献
845.
《International Journal of Sustainable Engineering》2013,6(6):420-428
AbstractThis research aims to characterise a recycled polymeric multi-material, explore potential areas of application for it and analyse the eventual impacts of the introduction of this new recycled material (NRM) on end-of-life activities. Thus, this research presents a practical study regarding recycled polymeric multi-material from toothbrushes. A preliminary characterisation (via density determination, tensile test and dynamic mechanical thermal analysis – DMTA) and data analysis using the Cambridge Engineering Selector (CES-Edupack 2013) software have been done. The study also presents an analysis of the impacts of introducing the NRM into end-of-life activities. Results shows that, based on the properties considered in this study, NRM may have potential for new applications. The impact on recycling networks indicates that it is a positive solution that would improve process variable efficiencies, maintaining material value as long as possible in industrial closed-loop life cycles. However, an in loco analysis of the treatment of waste containing the NRM is necessary. 相似文献
846.
Peter J. Taylor 《Local Environment》2013,18(4):495-508
The Transition Initiative is a highly successful movement promoting localisation of economic processes. The basic question that this essay considers is how to relate this movement's favoured units of practice, transition towns with populations of around 5000, to the contemporary world of large cities, so-called world cities, global cities and mega-cities. My means to achieve this end is to interrogate the concept of “local” to make it more strategically amenable to analysing multiple-scale living, and concomitantly, to recognise and understand the importance of non-local spheres of behaviour. The latter is derived from Jane Jacobs work on the city in which the balance between local production and imported (non-local) production is crucial. Her import replacement argument is used to show compatibility between economic change and sustainability. This leads to the concept of green networks of cities which I begin to explore. 相似文献
847.
水污染物排放总量控制方法研究--以无锡城北地区为例 总被引:1,自引:1,他引:0
水环境已经成为整个苏南地区经济发展的制约因素之一,为实现经济效益与环境效益协调发展,对水污染物排放实行总量控制至关重要。在对无锡城北地区水污染物负荷、水环境现状及水环境功能充分调查的基础上,结合该区域的水文特征和排水规划,统计分析出区域内水污染物的排放总量,根据污水集中处理方案,计算出区域水污染物的削减量,然后运用河网水质模型,预测水污染物削减后河流水质改善状况,以改善后水环境质量为本底值,以下游水环境保护目标的环境功能为控制要求,反推该区域在污水实行集中处理后所能接纳的水污染物排放总量。通过科学计算得知区域水环境纳污能力为19.8 t/d,由此确定的经济规模有限,必将制约地方经济的发展,提出了扩大水环境纳污能力的有效途径,并提出了建设无锡地区污水入江通道的设想。 相似文献
848.
邢振纲 《城市环境与城市生态》2005,18(2):1-3
以科学发展观为指导,天津市近年来环保工作取得了显著成绩,其主要做法有:加强执政能力建设;大力发展循环经济;创建环保模范城市。今后要进一步加大环保工作力度,为构建和谐社会做出贡献 相似文献
849.
Study on the conversion of waste plastics/petroleum resid mixtures to transportation fuels 总被引:4,自引:0,他引:4
Mohammad Farhat?AliEmail author Mohammad?Nahid Siddiqui S. Halim Hamid?Redhwi 《Journal of Material Cycles and Waste Management》2004,6(1):27-34
Catalytic coprocessing of model and waste plastics with light Arabian crude oil residue was investigated using NiMo/Al2O3, ZSM-5, FCC, and hydrocracking catalysts. Reaction systems that were studied included low density polyethylene (LDPE), high density polyethylene (HDPE), polystyrene (PS), and polypropylene (PP). A series of single (plastic/catalyst) and binary (plastic/resid/catalyst) reactions were carried out in a 25-cm3 micro autoclave reactor under different conditions of weight and type of catalyst, duration, pressure, and temperature. The optimum conditions selected for our work were: 1% catalyst by weight of total feedstock weight, 60min reaction time, 8.3Mpa of H2, and 430°C. The product distribution for the binary system using plastic and petroleum residue provided some encouraging results. High yields of liquid fuels in the boiling range of 100°–480°C and gases were obtained along with a small amount of heavy oils and insoluble material such as gums and coke. In general, this study helps to demonstrate the technical feasibility of upgrading both waste plastics and petroleum resid, as well as an alternative approach to feedstock recycling. 相似文献
850.
The household-recycling rate in the Borough of Burnley, England in 2001/2002 was only half the national average of 12%. This research employed both quantitative and qualitative surveys in order to ascertain whether householders’ attitudes to recycling were contributory factors to the generally poor recycling performance and to investigate other social, cultural and structural influences. The Borough has a large Asian–British population concentrated in two deprived wards where recycling rates are particularly low, so special attention was given to ascertaining their attitudes towards recycling.The quantitative survey comprised a postal questionnaire sent to a random sample of 360 households drawn from the electoral register. The qualitative survey consisted of group interviews with the Asian–British population at local community centres and focus groups attended by volunteers from the quantitative study.The findings suggest that householders are very willing to participate in recycling, as shown by the almost 80% claiming to recycle paper, but that local recycling services are too unreliable and inconvenient to allow them to do so comprehensively. Asian–British attitudes to recycling were found to be no different to those of the wider population, with their low participation being linked to the higher priorities imposed upon them by economic deprivation. The findings are broadly in line with those of the literature in that recycling participation tends to be higher among more affluent and older people, but lower among less affluent and younger households, probably due in part to the availability of both storage space and time, with the implication that the Borough's preponderance of terraced housing militates against a high recycling rate. Policy recommendations to local authorities include the provision of bespoke recycling services to suit the variety of residential conditions across the UK, and the provision of regular feedback to householders regarding recycling services and performance.Further research is needed to identify non-recyclers and to explore how householders’ underlying psychological, cultural and social attitudes to recycling impinge upon recycling and participation rates. 相似文献