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51.
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   
52.
The choices of policy targets and the formation of agent expectations have been critical issues addressed by monetary policy management since the financial crisis of 2008. This paper evaluates macroeconomic stability in a new Keynesian open economy in which agents experience both cognitive limitations and asset market volatility. The (im)perfect credibility of various monetary policies (e.g., a Taylor-type rule with- or without asset price targeting, strict domestic inflation targeting, strict CPI inflation targeting, and exchange rate peg) may lead agents to react according to their expectation rules, and thus create various degrees of booms and busts in output and inflation. Simulations confirm that a Taylor-type CPI inflation targeting including an asset price target is the best choice. In contrast, the business cycles induced by Keynesian “animal spirits” are enhanced by strict inflation targeting. Furthermore, a credible exchange rate pegging system with an international reserve pooling arrangement can improve social welfare and stability in an open economy, even though its absolute value of the loss function is slightly lower than a Taylor-type CPI inflation targeting including an asset price target.  相似文献   
53.
龙建平 《价值工程》2022,41(7):108-111
针对富水地层开仓换刀存在诸多不确定性因素的技术难题,本研究结合福州地铁6号线滨海新城站~壶井站区间盾构开仓换刀施工,通过对盾构近期掘进参数、工程地质、水文地质情况进行分析的基础上,提出了先进行盾构机防包裹保护、水泥砂浆置换土仓渣土填仓,施作盾尾止水环,再进行地表深孔注浆加固,确保开挖仓掌子面稳定的前提下;再常压进行刀具...  相似文献   
54.
In this paper we propose a model that explains how cooperation can emerge spontaneously between firms in a highly competitive market environment. The basic idea is that the more competitive is the market, the less costly it is for firms to help each other like good neighbors. Cooperation takes the form of sharing technical know-how, which speeds up the adoption of new technologies (normally developed elsewhere) that spur industrial development. The model comports with the development history of Japan's first example of successful industrial development – its cotton spinning industry – whose conditions match those of firms in small open economies today.  相似文献   
55.
气候变化对欧洲农业的系统影响及对策   总被引:1,自引:0,他引:1  
本文基于欧洲气候变化的历史演进与未来情景,系统分析了气候变化对欧洲农业的历史和潜在影响,提供了欧洲农业应对气候变化的适应性措施,及其对中国未来农业发展的启示和建议。  相似文献   
56.
This note applies the approach of Miyagiwa and Papageorgiou [Miyagiwa, K. and Papageorgiou, C., 2007. Endogenous aggregate elasticity of substitution. Journal of Economic Dynamics and Control 31, 2899–2919] to provide simple frameworks for endogenizing the aggregate elasticity of substitution between capital and labor for a growing small open economy.  相似文献   
57.
Governments around the world are forced to react to disasters caused by weather. The agricultural sector is particularly susceptible to weather extremes and adverse climate conditions. In the US, agricultural disaster payments account for a significant part of total agricultural subsidies. The payments, and their distribution, are more important in the areas most affected by disastrous weather events, usually coinciding with areas of pronounced impact of the El Nino Southern Oscillation (ENSO). In this article, the impact of weather and climate, as well as some economic variables, on disaster payments is analysed using county level data from four states in the southeastern United States. The results suggest that weather and climate variables explain most of the crop disaster payments at the county level while socioeconomic variables do not, suggesting that advancements in weather and climate forecasts could be helpful in planning for disaster compensation.  相似文献   
58.
In 2003 Japan proposed a Climate Change Tax to reduce its CO2 emissions to the level required by the Kyoto Protocol. If implemented, the tax would be levied on fossil fuel use and the revenue distributed to encourage the purchase of energy efficient equipment. Analysis using the MIT Emissions Prediction and Policy Analysis (EPPA) model shows that this policy is unlikely to bring Japan into compliance with its Kyoto target unless the subsidy encourages improvement in energy intensity well beyond Japan’s recent historical experience. Similar demand-management programs in the US, where there has been extensive experience, have not been nearly as effective as they would need to be to achieve energy efficiency goals of the proposal. The Tax proposal also calls for limits on international emission trading. We find that this limit substantially affects costs of compliance. The welfare loss with full emissions trading is 1/6 that when Japan meets its target though domestic actions only, the carbon price is lower, and there is a smaller loss of energy-intensive exports. Japan can achieve substantial savings from emissions trading even under cases where, for example, the full amount of the Russian allowance is not available in international markets.  相似文献   
59.
This study compares the accuracy and information content of economic forecasts for G7 countries made in the 1990s by the OECD and IMF. The benchmarks for comparison are the average forecasts of private sector economists published by Consensus Economics. With few exceptions, the private sector forecasts are less biased and more accurate in terms of mean absolute error and root mean square error. Formal tests show these differences are statistically significant for forecasts of real growth and production, less so for forecasts of inflation and unemployment. Overall, there appears little information in the OECD and IMF forecasts that could be used to reduce significantly the error in the private sector forecasts.  相似文献   
60.
当今世界生态与环境的诸多问题中,生态系统脆弱性是焦点问题之一.依据我国干旱半干旱地区草场退化、土地沙漠化及盐碱化等三种主要问题的剖析结果,分析了退化草原生态系统、绿洲生态系统、荒漠生态系统、湿地生态系统、农牧交错生态系统等五类主要脆弱生态系统的成因和生态性状.最后得出结论:气候异常和人类非理性活动是造成脆弱生态系统长时期处于恶性循环的主要原因,前者表现在气候变化和气候变异两方面,后者则以超载放牧、无序垦荒、无度利用有限水资源、乱樵滥采资源等四类为主.这些研究结论为我国干旱半干旱地区防止脆弱生态系统进一步退化和生态综合整治提供了理论基础.  相似文献   
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