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451.
The growing concerns over the environmental impacts of buildings have led to increasing demands for more environmental friendly buildings and building materials. Hitherto, there are not any comprehensive studies that show the overall environmental impact profiles of building materials and building services components for buildings. This paper intends to bridge this gap by reporting overall lifecycle environmental profiles of buildings as well as the ranking orders of environmental impacts of all the building materials and building services materials and components for commercial buildings. Twenty-five commercial buildings in Hong Kong, which include three Grade A office buildings, four Grade B office buildings, one Grade C office buildings, four retail centers and three hotels, have been selected for our study. Based upon these collected samples, no statistical differences were found in the average lifecycle environmental impacts for different building types despite some minor variations were detected. Subsequently, 10 types of building materials and 10 types of building services components have been identified for their significant lifecycle environmental impacts on commercial buildings. Among all, concrete, reinforcement bar, copper power cables, and copper busbars were ranked to be the four most significant materials or components to the total lifecycle environmental impacts. These should form the major targets for improvements in environmental performance of commercial buildings.  相似文献   
452.
Integrating mitigation and adaptation (M&A) is a practical reality for climate change response policy, despite a range of conceptual and methodological challenges. Based on the papers in this special issue, some preliminary findings about appropriate integrated portfolios are offered, along with several implications for climate policy.  相似文献   
453.
As climate changes due to rising concentrations of greenhouse gases in the atmosphere, agriculture will be one of the key human activities affected. Projections show that while overall global food production in the coming decades may keep pace with the food requirements of a growing world population, climate change might worsen existing regional disparities because it will reduce crop yields mostly in lands located at lower latitudes where many developing countries are situated. Strategies to enhance local adaptation capacity are therefore needed to minimize climatic impacts and to maintain regional stability of food production. At the same time, agriculture as a sector offers several opportunities to mitigate the portion of global greenhouse gas emissions that are directly dependent upon land use, land-use change, and land-management techniques. This paper reviews issues of agriculture and climate change, with special attention to adaptation and mitigation. Specifically, as adaptation and mitigation strategies in agriculture are implemented to alleviate the potential negative effects of climate change, key synergies need to be identified, as mitigation practices may compete with modifications to local agricultural practices aimed at maintaining production and income. Under future climate and socio-economic pressures, land managers and farmers will be faced with challenges in regard to selecting those mitigation and adaptation strategies that together meet food, fiber and climate policy requirements.  相似文献   
454.
铜鼓航道工程建设对中华白海豚的影响分析   总被引:1,自引:0,他引:1  
中华白海豚是国家一级重点保护的野生濒危动物,深圳铜鼓航道部分路线会穿越珠江口中华白海豚自然保护区,对白海豚产生不良影响。文中结台白海豚的生态特点,分析了工程对白海豚的影响,并提出了相应的保护对策。  相似文献   
455.
钭晓东 《四川环境》2003,22(3):8-12
为平衡旅游开发过程中的经济与环保利益,作为一种全新旅游理念与旅游发展形式的“生态旅游”应运而生,也对传统旅游结构的演变提出挑战,西方通过对“生态旅游”的概念、特性、构成要素、核心内涵、历史使命的解析,以求能为“生态旅游”发展的可持续性,从而为结合“经济效益”、“生态支柱”、“文化内涵”的新型旅游发展模式提出思考。  相似文献   
456.
ABSTRACT: This paper presents an analysis of the effects of different institutional arrangements and economic environments on water markets. Characteristics of water rights transfers in the South Platte Basin of Colorado and transfers of shares of the Northern Colorado Water Conservancy District (NCWCD) are compared to show how different institutional arrangements can affect the types and size distributions of transfers. The characteristics of water rights transfers in the prosperous South Platte are then compared with water rights transfer characteristics in the economically marginal Arkansas River basin of Colorado to identify the effects of different economic environments. Finally, the economic losses from reductions in irrigated acreage resulting from water transfers are estimated for the South Platte and Arkansas and compared with purchase prices by municipalities. Transfers in the South Platte were to new uses in the same basin, while more recent transfers in the Arkansas were to out of basin users. Transfers of South Platte rights and especially NCWCD shares were small and continuous over time, while transfers in the Arkansas were dominated by a few very large transfers. The negative impacts are judged to be more severe in the Arkansas basin than in the South Platte. Purchase prices paid by municipalities substantially exceeded capitalized transitional losses in the selling areas. In the South Platte, gains and losses were in the same basin, while the Arkansas absorbed the losses, with the benefits going to the purchasing basin.  相似文献   
457.
中国工业行业的生态效率   总被引:5,自引:2,他引:3  
毛建素  曾润  杜艳春  姜畔 《环境科学》2010,31(11):2788-2794
中国工业是资源消费和污染物排放的主要源头,解析工业各行业的生态效率可为中国产业结构调整和整体环境质量改善提供必要信息.在分析工业构成并构建工业系统与外部环境之间关系的基础上,选择能源消费和废水、固体废物、SO2、工业烟尘、粉尘等污染物的排放量作为研究的环境影响类别,界定了与这些环境影响相关的生态效率,估算了中国2007年的工业生态效率现状,结果为:能源效率615.5万元·ktce-1;废水和固废方面的生态效率分别为54.3万元·kt-1和1.9万元·t-1;工业SO2、烟尘和粉尘方面的生态效率分别为59.6、169.2和184.6万元·t-1.深入分析了39个工业部门的生态效率,结果表明,以上几种生态效率具有明显的行业不均衡性,表现为不同行业在不同类型生态效率中的工业排序明显不同;与此同时,对于同一种生态效率,不同工业行业的数值可相差几百倍到几万倍,表明通过优化工业结构将具有较大的提高工业生态效率的可能性.  相似文献   
458.
The methodologies, approaches and indicators for assessing the impacts of freshwater usage are still evolving. The development of the water footprint concept has been an important step in this direction but the existing methodologies mainly assess the quantity of water used rather than the related impacts. Although there is a recognised need to consider the latter, particularly on a life cycle basis, the difficulty is that there are little or no reliable data on water usage in life cycle databases; furthermore, there is no agreed life cycle impact assessment method for estimating impacts related to freshwater use. However, there have been some methodological developments which propose methods for inventory modelling and impact assessment for water use in life cycle assessment. This paper reviews some of these approaches and discusses their strengths and limitations through a case study, which considers the impacts of freshwater consumption from corn-derived ethanol produced in 12 different countries. The results show a huge variation in the results between different methods and demonstrate the need for a standardised methodology for assessing the impacts of water use on a life cycle basis. Specific recommendations for further research in this field have been made accordingly.  相似文献   
459.
转基因植物指的是利用DNA重组技术克隆基因导入植物细胞或组织,从而使植物表现出新的性状。基因交流的范围会无限的扩大,可从病毒、细胞、植物等导入植物,因此我们顾虑:人工转基因转人植物,会不会释放到环境中后产生严重的环境污染。鉴于此,本文做出了人工释放转基因植物对群落结构影响的分析。  相似文献   
460.
Contemporary changes in open water surface area of Lake Inle, Myanmar   总被引:1,自引:0,他引:1  
From 1935 to 2000, the net open water area of Inle Lake in Central Shan State, Myanmar decreased from 69.10 to 46.69 km2, a loss of 32.4% during this 65-year period. Local beliefs are that losses in lake area have been even greater within the last 100–200 years. Various activities, including timber removal, shifting agriculture in the uplands by various ethnic groups, and unsustainable cultivation practices on the low- and mid-level hillslopes around the lake, have been blamed for both historical and ongoing sedimentation. We take issue with attributing loss of lake area to these activities, and propose instead that ongoing “in-lake” and “near-lake” agricultural practices are the main sources of contemporary sediment and loss of open water area. About 93% (i.e., 20.84 km2) of the recent loss in open water area of the lake is due to the development of floating garden agriculture, largely along the west side of the lake. Direct environmental impacts associated with this practice and with other agriculture activities within the wetlands and margins of the lake include sedimentation, eutrophication, and pollution. Whilst the sustainability of hillslope agriculture and past forestry practices can indeed be questioned, a more urgent need is to address these "in-lake" and "near-lake" practices.  相似文献   
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