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951.
基层环境监测能力效率的思考和建议 总被引:1,自引:0,他引:1
基层环境监测站是环境保护和环境监测的基础。在此重点在职责定位、经费投入、人员素质、监测项目、质量管理等方面对县(区)基层环境监测站的现状和能力建设及存在的问题进行深入探讨,并对环境监测站的能力建设和提高工作效率提出相应的建议和对策。 相似文献
952.
为探明水幕排烟系统对隧道内烟气控制和排烟效率的影响,通过火灾动力学求解器(FDS)研究不同排烟风量下隧道内烟气、温度和速度分布。结果表明:排烟量小于100 m3/s时,水幕无法有效地阻隔有毒烟气的蔓延;当火源热释放速率(HRR)为10、20及30 MW时,排烟量分别为100、160和180 m3/s,能将烟气限制在水幕排烟系统内;在水幕的作用下,水幕外的温度分布均满足人员逃生的需要(小于80℃),在水幕排烟系统中烟气控制要比温度控制更为重要;相同火源HRR下,排烟口的排烟效率随着排烟量先增大后减小;排烟口的吸穿效应在水幕排烟系统中很难出现,排烟口吸入位于隧道底部混有大量新鲜空气的烟气是造成排烟效率降低的主要原因。 相似文献
953.
Synergisms between climate change mitigation and adaptation: an insurance perspective 总被引:1,自引:0,他引:1
Evan Mills 《Mitigation and Adaptation Strategies for Global Change》2007,12(5):809-842
As the world’s largest industry, the insurance sector is both an aggregator of the impacts of climate change and a market
actor able to play a material role in decreasing the vulnerability of human and natural systems. This article reviews the
implications of climate change for insurers and provides specific examples of insurance-relevant synergisms between adaptation
and mitigation in the buildings and energy sectors, agriculture, forestry, and land use. Although insurance is far from a
“silver bullet” in addressing climate change, it offers significant capacity and ability to understand, manage, and spread
risks associated with weather-related events, more so today in industrialized countries but increasingly so in developing
countries and economies in transition. Certain measures that integrate climate change mitigation and adaptation also bolster
insurers’ solvency and profitability, thereby increasing their appeal. Promising strategies involve innovative products and
systems for delivering insurance and the use of new technologies and practices that both reduce vulnerability to disaster-related
losses and support sustainable development. However, climate change promises to erode the insurability of many risks, and
insurance responses can be more reactive than proactive, resulting in compromised insurance affordability and/or availability.
Public–private partnerships involving insurers and entities such as the international relief community offer considerable
potential, but have not been adequately explored.
相似文献
Evan MillsEmail: URL: http://insurance.lbl.gov |
954.
Set-aside management: How do succession, sowing patterns and landscape context affect biodiversity? 总被引:1,自引:0,他引:1
Teja Tscharntke Péter BatáryCarsten F. Dormann 《Agriculture, ecosystems & environment》2011,143(1):37-44
European Union (EU) member states set aside between 5 and 15% of arable land during the last two decades, but abolition of the set-aside scheme in 2008 caused a sudden loss in habitat availability and biodiversity in agricultural landscapes. Management of set-aside has many facets and in this perspective paper we focus on the biodiversity effects of successional age, sowing strategies and landscape context. Young, 1-2-year-old set-asides have been initially considered to be too ephemeral to have any conservation value. However, when a rich seed and bud bank is available, a species-rich natural (secondary) succession can be observed. Arable (annual) weed communities in the first two years of succession can even include endangered plant species with associated rare insect consumers. Furthermore, many bird species benefit from early-successional habitats, whereas small mammal communities are richer in older habitats. If the local plant species pool is poor, sowings of diverse mixtures from regional seed collections can be recommended. Set-aside managers using species-rich sowings often experience that dominant weeds suppress the less competitive annual species. This trend to species-poor communities can be avoided by intraspecific aggregation of competitively weak species. Broadening the spatial scale from the plot to the landscape, efficiency of set-aside is highest in simple landscapes, where set-aside exhibits greatest effect in enhancement of biodiversity and associated services such as pollination and biological control. In complex landscapes, however, additional set-aside does not add much to the high level of biodiversity and ecological processes already present. Twenty percent of semi-natural, non-crop habitat appears to be a rough threshold for enhancing biodiversity and sustaining services such as pollination and biological control, but improved set-aside management should have the potential to reduce the percentage of semi-natural non-crop habitat needed. EU policy should tailor set-aside schemes for the maintenance of biodiversity and also consider that management efficiency is higher in simple than complex landscapes. 相似文献
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957.
Collaborative activities with business partners have potential to improve environmental performance of product and life cycle assessment (LCA) is an essential technique to implement eco-design of product and production process. However, collection of LCA data from supply chain is a major issue for LCA practitioners. We propose a Supply Chain Collaboration Model (SCCM), which is a framework for collecting producer-specific LCA data from business partners and for promoting improvement activity of product environmental performance. We demonstrate the practicability of the SCCM using three case studies. In each case study, two or three partner companies organized a product improvement project and carried out process analysis techniques such as LCA and material flow cost accounting (MFCA). As a result, improvement activities from the economical standpoint could provide an incentive for business partners to collect LCA data, and thus the SCCM is an effective framework for eco-design. 相似文献
958.
Path creation for sustainable consumption: promoting alternative heating systems in Finland 总被引:1,自引:0,他引:1
There are many cost-effective technologies to reduce resource use and carbon dioxide emissions in space heating, yet they are adopted very slowly, and inefficient heating systems persist. In this article, we examine path dependence and path creation in home heating systems. Path dependence refers to the self-sustaining characteristics of existing systems such as the dominant energy system. Path creation is a related concept that highlights entrepreneurship in ‘mindfully deviating’ from existing paths and creating new ones by engaging various stakeholders and generating momentum. Research on path creation in energy systems has focused on energy production systems, whereas end-use technologies have gained less attention. We explore the role of path creation in end-use technologies through four attempts to change heating systems for detached houses in Finland via the promotion of heat pump technologies. Within the path creation process, we focus on how the initiators of new paths try to counter the forces maintaining the dominant system. In particular, we pay attention to how small organizations make use of co-operation to challenge the existing path. The aim is to identify the conditions for successful path creation by entrepreneurs and energy end-users under adverse conditions. 相似文献
959.
Yannay CasasJo Dewulf Luis E. Arteaga-PérezMayra Morales Herman Van LangenhoveElena Rosa 《Journal of Cleaner Production》2011,19(13):1395-1404
The effect of the integration of Solid Oxide Fuel Cell (SOFC) technology in a sugar-ethanol factory on the environmental profile/footprint of the products (sugar, ethanol, electricity) is evaluated. The sugarcane is the primary feedstock and sugar, ethanol and electricity are the main products of the system, where the functional unit is defined as 9.86 ton/h of sugar, 2.195 ton/h of hydrated ethanol (96% w/w) and 847 kWh of electricity. A detailed set of material and energy inputs and outputs was obtained from a local factory and was completed using simulation data by Aspen Plus®.The environmental impacts (greenhouse gases and air pollution), exergy efficiency and a renewability parameter have been considered as indicators for the comparative assessment with conventional sugar, ethanol and electricity production technologies. The results show that the use of a SOFC technology involves a reduction of greenhouse gas emissions (52-55%) and non-renewable resources (60-64%) when compared with the conventional integrated sugar and ethanol plant. The higher renewability index (0.93) and exergy efficiency (38%) are noticed for the Solid Oxide Fuel Cell technology integrated in the sugar-ethanol factory than conventional sugar-ethanol plant. 相似文献
960.
The mercury removals by existing pollution control devices in four coal-fired power plants of China were carried out based on a measurement method with the aluminum matrix sorbent. 相似文献