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71.
There is a profound debate over how to assign greenhouse gas (GHG) responsibilities; therefore, we have decided to follow IPCC guidelines, as they offer the only standardized method. We have identified each type of greenhouse emission and its level of absorption. We have studied the province and its districts and municipalities. We have determined that the energy sector is that with the highest level of emissions, even if the per capita emissions of the Province of Siena are very low. This is caused by a very low level of industrialization and the presence of a local geothermal production of energy. In order to highlight this aspect, we have considered scenarios both with and without geothermal production. Our research was then focused on single districts (groups of homogenous municipalities) and municipalities, where we found great differences among the greenhouse emissions of the areas. We have constructed a map of the greenhouse emissions of the whole province. It has been interesting to note that there are 14 municipalities with net negative emissions, seven with low positive emissions, 12 with medium positive emissions and three with elevated positive emissions. These latter correspond to the main city and to two of the most industrialized municipalities.  相似文献   
72.
碳氮磷比失调对污水生物脱氮除磷的影响   总被引:1,自引:0,他引:1  
宋周兵  于薇 《四川环境》2008,27(6):73-76
我国南方城市污水普遍存在低碳相对高氮磷特征,本文介绍了同时生物脱氮除磷的机理、对碳源的需求与竞争,以及一些针对此类污水生物脱氮除磷的改进工艺及其在实际运用中的效果,并对此类污水的处理方向进行了展望。  相似文献   
73.
畜牧业“碳排放”到“碳足迹”核算方法的研究进展   总被引:1,自引:0,他引:1  
全球变暖趋势日益加剧,不仅影响农业可持续发展,而且威胁到人类生存。畜牧业碳排放因其在农业碳排放中乃至全球碳排放中占比较大而日益备受关注。准确核算畜牧业碳排放是制定切实可行的碳减排政策的前提,也为我国在气候变化下承担共同但有差别的减排责任提供话语权。本文基于研究范式的演进,对畜牧业碳排放到碳足迹核算方法的研究发展进行了系统梳理,研究表明,在学者的不断研究与质疑下,畜牧业碳排放到碳足迹的核算方法经历了从OECD核算法、IPCC系数法到生命周期法与投入-产出法的演变与完善,学术界认为区域异质性、养殖规模与管理方式均影响碳足迹;散养比规模化养殖产生更多的碳排放,舍饲比户外放牧排放更多的碳。畜牧业碳足迹核算能够更加全面地反映畜牧业全生命周期的碳排放情况,但由于研究假设、研究方法及研究样本等差异导致不同区域、不同畜产品的碳排放核算结果存在不确定性。运用生命周期法和投入-产出法对欧盟成员国畜牧业碳排放的核算结果基本一致,但运用IPCC系数法和全生命周期法对中国畜牧业碳排放核算中,牛、猪和羊的碳排放量排序结果不尽一致。鉴于核算结果的差异性,本研究对不同核算方法的起源、最早采用时间、特点、局限性等方面进行了归纳总结,并建议后续研究探讨基于生命周期评价的畜牧业碳足迹研究边界的延伸性,标准化畜牧业碳排放或碳足迹核算,避免学者重复核算畜牧业碳排放,以便深入展开畜牧业碳排放其他方面的研究。  相似文献   
74.
Matthew Daly 《Local Environment》2017,22(11):1358-1377
Many intentional communities worldwide, such as ecovillages and co-housing communities, have explicit goals of living in an environmentally sustainable manner, and are taking conscious steps towards these goals in response to the widely discussed unsustainability of the global sociotechnical system. There are numerous claims from researchers and community members, in the academic and grey literature, that intentional communities are making significant improvements towards sustainability goals, particularly in terms of environmental impact. However, actual measures of progress, with evidence supporting these claims, are relatively scarce. This paper presents the findings of a systematic review of quantitative studies of the environmental impact of intentional communities, including comparisons with relevant “mainstream” communities. The review focused on the two indicators that are most commonly reported in studies of the impact of intentional communities – the ecological footprint and the carbon footprint. This review was undertaken as there is a lack of literature reviews that comprehensively compile existing quantitative studies about intentional communities. In total, the review identified 16 separate studies covering 23 communities and 30 footprint measurements, with publication dates ranging from 2000 to 2014. This is a greater number of studies than in any other literature review of this topic. Taken as a whole, these compiled studies provide strong support for claims of greater environmental sustainability within these communities, and reinforce the need for greater research and exploration of the role sustainability-oriented intentional communities can play in the transition to more sustainable sociotechnical systems.  相似文献   
75.
Check-dams are the most common structures for controlling soil erosion in the Loess Plateau. However, the effect of check-dams on carbon sequestration, along with sediment transport and deposition, has not been assessed over large areas. In this study, we evaluated the carbon sequestration function of check-dams in the Loess Plateau. The results indicate that there were approximately 11 000 check-dams distributed in the Loess Plateau, with an estimate of the amount of sediment of 21 × 109 m3 and a soil organic carbon storage amount of 0.945 Pg. Our study reveals that check-dams in the Loess Plateau not only conserve soil and water but also sequester carbon.  相似文献   
76.
Although composting has been successfully used at pilot scale to manage waste algae removed from eutrophied water environments and the compost product applied as a fertiliser, clear guidelines are not available for full scale algae composting. The review reports on the application of composting to stabilize waste algae, which to date has mainly been macro-algae, and identifies the peculiarities of algae as a composting feedstock, these being: relatively low carbon to nitrogen (C/N) ratio, which can result in nitrogen loss as NH3 and even N2O; high moisture content and low porosity, which together make aeration challenging; potentially high salinity, which can have adverse consequence for composting; and potentially have high metals and toxin content, which can affect application of the product as a fertiliser. To overcome the challenges that these peculiarities impose co-compost materials can be employed.  相似文献   
77.
相震 《四川环境》2012,31(3):70-75
中国强制碳交易标的物的确定、排放权的分配、排放源的监测核查等制度设计尚不明晰,也未出台温室气体交易活动的相关管理办法,碳减排体系尚未真正确立。碳市场处于初建期、探索期。通过对碳交易活动的背景、实质、运行机制以及国内碳交易现状的分析,结合应对气候变化的国际进展和国内政策行动对中国碳交易市场发展对策进行了探讨。  相似文献   
78.
The concept of sustainable development has become very much in vogue in the past decade. We have also observed a shift in the interpretation of this concept from a global perspective to a meso perspective—that is, at a local, regional or sectoral level. This paper aims at highlighting the urban dimension of environmental issues. After a sketch of urban pollution problems and of tools for economic analysis, the notion of urban sustainability will be advocated as a meaningful analytical and policy concept. Next, the main focus of this paper will be on a typological approach to urban sustainability issues on the basis of three characteristic angles, viz. strong and weak sustainability, absolute and relative decoupling and the spatial ecological footprint. Various methodological issues will also be discussed, while the paper will conclude with some perspectives on policy issues. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
79.
This experimental research addresses the effectiveness of communication about complex environmental issues, depending on whether the same information is provided by multiple collaborating or by individual organizations (i.e., stakeholders). The information provided pertains to carbon dioxide capture and storage (CCS) technology, as an example of a complex environmental issue. In Studies 1 (N = 75) and 2 (N = 66) we found that participants perceived factual information from collaborating stakeholders to be of higher quality than when the same information was provided by individual stakeholders. As predicted, the expectation of diverse perspectives being represented in the collaborative information mediated this effect. In addition, in Study 3 (N = 79) the perceived dissimilarity of collaborating stakeholders was shown to be an important precondition for the collaboration effect observed in Studies 1 and 2. Finally, these studies indicate that occasional collaboration between different stakeholders does not necessarily harm the perceived credibility of each individual stakeholder.  相似文献   
80.
根据生态足迹分析方法,建立了水资源生态足迹概念模型,确定了计算水资源帐户生态足迹所需的3个关键参数,即平均水资源产量、均衡因子和地区产量因子,计算了安康市1996—2007年水资源生态足迹和生态承载力。引入水资源生态足迹压力指数、万元GDP水资源生态足迹、累积水资源生态足迹等指标,利用水足迹模型评价水资源可持续发展程度的全面性和对比性。结果表明,计算结果可客观评价安康市水资源可持续发展与利用情况,为地区水资源的可持续利用与管理提供了科学的依据。  相似文献   
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