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11.
建筑外墙氟碳涂料克服了以往氟碳涂料不能常温固化的缺点,能应用于混凝土等无机材质的表面。由于其具有超耐候性等卓越性能,已受到业主、设计的关注和市场的认可,在外墙饰面中将得到广泛应用。文章浅析了外墙氟碳涂料的材料特性,阐述了外墙氟碳涂料施工阶段的质量事前控制、事中控制和事后控制;对某工程外墙氟碳涂料施工质量缺陷产生的原因进行了分析,提出了相应的预控措施。 相似文献
12.
基于2013-2020年的30个省份数据构建面板数据模型,从碳排放总量和碳排放强度两个视角研究数字经济发展对区域碳排放的影响。研究发现:数字经济的发展有效地降低了人均碳排放量、碳排放增量与碳排放增速,数字经济与碳排放强度之间存在倒“U”形关系,数字经济与碳排放强度、边际碳排放强度的关系呈现区域性特征,在省域层面数字经济对边际碳排放强度的影响不存在明显的空间效应,数字经济对碳排放增长率的影响存在基于产业结构优化、人口集聚、城镇化的遮掩效应。 相似文献
13.
Odd Godal Yuri Ermoliev Ger Klaassen Michael Obersteiner 《Environmental and Resource Economics》2003,25(2):151-169
The Kyoto Protocol foresees emission trading but does not yet specify verification of (uncertain) emissions. This paper analyses a setting in which parties can meet their emission targets by reducing emissions, by investing in monitoring (reducing uncertainty of emissions) or by (bilaterally) trading permits. We derive the optimality conditions and carry out various numerical simulations. Our applications suggest that including uncertainty could increase compliance costs for the USA, Japan and the European Union. Central Europe and the Former Soviet Union might be able to gain from trading due to higher permit prices. Emissions trading could also lower aggregate uncertainty on emissions. 相似文献
14.
This paper discusses and contrasts two mainroles of forestry in light of the debate on theglobal climate. As the main problem is relatedto the increases of the CO2-concentrationin the atmosphere, forests may be viewed aspart of the alleviation of the problem throughtheir function as (i) a source of biomass forenergy production, which may replace fossilfuels and thus indirectly reduceCO2-emissions, and as (ii) carbon storage,since a growing forest extracts atmosphericCO2 and fixes it as carbon in biomass. Inthe Scandinavian forestry, logging residues areincreasingly being used for energy production.In this paper the value of forests as a sourceof bioenergy is added to the traditional timbervalue. Formulated as a joint production modelwithin the Faustmann framework, the effect ofthis addition on the optimal rotation length isdiscussed. Based on data for spruce, thedominant species in the Scandinavian forestry,it is demonstrated that the rotation length isshortened compared to the standard Faustmannmodel. Shorter rotation length implies lesscarbon storage. Therefore, in this modelwithout explicit regard to the social carbonstorage value of the forest, the gains in termsof the climate problem from utilisation offorest biomass for energy production are beingdiminished by the value of reduced carbonstorage. The carbon value of the forest is thenadded to complete the model, with the effect ofincreasing the rotation length, a result thatis well known in the literature. Finally, theempirical effects of the interaction of thesetwo climate-related value elements of theforest are discussed. 相似文献
15.
Anne-Sophie Crépin 《Environmental and Resource Economics》2003,26(4):625-646
Recent research in natural sciences shows that the dynamics in boreal forests are much more complex than what many models
traditionally used in forestry economics reflect. This essay analyzes some challenges of accounting for such complexity. It
shows that the optimal harvesting strategy for forest owners is history dependent and for some states of the forest, more
than one strategy may be optimal.This paper confirms earlier literature on shallow lakes and coral reefs and shows that this
kind of phenomena seem much more common than previously thought. They are valid for a wide range of ecosystems that cover
large surfaces and they do not depend on the choice of some specific function to model the non-linearity. There are also indications
that theses results could be obtained even for resources with concave growth if at least one species with non-linear growth
affects their dynamics. 相似文献
16.
Our main objective is to set out and apply a SEEA-based methodology to reflect the true value of forest resources in India's national and state accounts. We establish that a “top-down” approach using available national databases is both feasible and desirable from a policy perspective. In this paper, we address four components of value creation in forests: timber production, carbon storage, fuelwood usage, and the harvesting of non-timber forest products. The results of our analysis suggest that prevailing measures of national income in India underestimate the contribution of forests to income. The income accounts of the Northeastern states in particular are significantly understated by these traditional (GDP/GSDP) measures. We are also able to identify some states which performed poorly in the context of our sustainability framework, reflecting natural capital losses due to degradation and deforestation. Our results highlight the need to integrate natural resource accounting into the national accounting framework in order to generate appropriate signals for sustainable forest management and for the conservation of forest resources which are widely used by the poor in India, as well as being significant stores of national wealth. 相似文献
17.
Urs Springer 《Environmental and Resource Economics》2003,25(4):501-513
Through Joint Implementationand the Clean Development Mechanism, reductionsof greenhouse gas emissions achieved abroad canbe credited to domestic firms. However, thetechnical, economic and political risksinvolved may prevent the private sector frominvesting in such projects. This paperdescribes three types of risks which emissionreduction projects are exposed to. Eleven pilotprojects carried out under the ActivitiesImplemented Jointly (AIJ) program and financedby Sweden are evaluated. Actual project costsare found to exceed projected costs in allcases. Annual emission reductions also deviatefrom their expected values and vary stronglyover time, supporting the hypothesis that suchprojects are risky business. The riskmanagement tool portfolio diversification isapplied to a sample of Swedish AIJ projects.The results indicate that diversification canreduce the risks of greenhouse gas mitigationprojects significantly. Thus, carbon funds area promising way of lowering the risks of theKyoto Mechanisms for private sector investors. 相似文献
18.
以绿色农业发展为导向,选择农业碳排放作为非期望产出指标,采用超效率的SSBM模型和探索性空间数据分析(ESDA)相结合的方法,以县域单元为尺度对2000-2017年安徽省农业效率水平、空间格局及其演变趋势进行实证分析。研究发现:①传统DEA模型忽视了农业碳排放等非期望产出的负面效应,从而高估农业资源利用的实际状态,基于超效率的SSBM模型更符合实际情况,能较好地识别各评价单元之间的优劣关系。②研究期内,安徽省农业效率值呈波动式上升态势,但总体上处于效率中等水平,农业效率空间分布不均衡,呈现出皖南地区>皖中地区>皖北地区的空间分布格局;空间变化趋势呈现自西向东递增、自北向南U型增长的变化态势,南北差异的增大是安徽省县(市、区)农业效率差异增大的主导因素。③除2010年外,安徽省农业效率呈正相关,空间差异有所缩小,但空间集聚程度相对较弱;安徽农业效率HH集聚县区集中分布于皖南地区,且呈现出向周边县区扩散的态势,LL型县(市、区)则主要分布在皖北地区,且空间分布较为稳定。④研究期内,安徽省农业效率空间正相关的县(区)数量有所增加,表明该时间段内安徽省农业效率空间上进一步集聚,LL型集聚的皖北地区应当是安徽省农业发展关注的重点。 相似文献
19.
There is currently substantial interest in valuing various services provided by different ecosystems. Concurrently economists have ascribed substantial effort on expanding traditional forest accounting systems by environmental services. This paper contributes to curtailing the existing gap between green accounting theory and applications for valuing forest ecosystem services. The multitude of links between forest ecosystem services and economy are characterized by the theoretical model for forest-economy interactions. By utilizing recently updated data we also incorporate empirical value estimates of these services comparable to other goods into Finnish forest accounting system. Finally, we discuss some problems encountered and clarify the interpretation of some value estimates incorporated to national forest account. 相似文献
20.
城市森林固定CO2价值评估 总被引:1,自引:0,他引:1
本文利用我国第四次森林资源清样调查资料对上海市森林植被碳储量和碳密度的估算结果,结合植物的光合作用过程计算上海市森林固定CO2的能力,采用造林成本法对上海市森林固定CO2的价值进行了评估。笔者希望通过该研究激发人们保护城市森林以维持城市生态系统可持续发展的积极性,并为合理地进行城市森林管理和城市绿化提供参考。另外,利用系统连续的森林资源清样调查资料评估森林植被的固碳价值,能够对我国更好地履行《联合国气候变化框架公约(》UNFCCC),并为依据《京都议定书(》KyotoProtocol)进行环境外交提供帮助。 相似文献