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1.
《Scandinavian Journal of Forest Research》2012,27(2):155-172
The objective of this study was to compare different methods of estimating the demand equations of global forest sector models. Past applications have shown that model projections depend critically on the elasticity of demand with respect to income and prices. To measure the elasticity coefficients, nine groups of products were examined, ranging from fuelwood to paper and paperboard, in 64 countries. The analysis was done with panel data on consumption, price and income, from 1973 to 1997. Two alternative forms were hypothesized: a static demand model, and a dynamic partial adjustment model. The demand equations were estimated first with classical panel methods: ordinary least squares pooling of country data, least squares with country dummy variables, between group pooling and error-component models. However, rejection of the hypothesis of homogeneity of elasticities across countries led to the investigation of two shrinkage estimators: the Stein rule and the iterative empirical Bayes estimator. Within-sample predictions were carried out to compare the accuracy of each estimator. The Stein rule estimator, based on the static model, gave the smallest root mean square error. Nevertheless, because the Stein-rule estimates often had theoretically wrong signs and large variances, other estimators, although biased, were deemed preferable for policy analysis. In conclusion, pooling by ordinary least squares with country dummy variables was one of the most useful methods to obtain demand equations applicable to many countries. Furthermore, static models predicted demand better than dynamic models, conditional on price and national income. 相似文献
2.
LiuJunchang HuMingxing 《中国林学(英文版)》2004,6(1):42-47
Based on the current conditions, a forecast of trends in imports and exports of wood products and their demand and supply is presented in this paper for the years of 2005 and 2015. It is expected that imports will continue to exceed exports but that the trade deficit in wood products will decline. The form of trade will be changed from a condition of unilateral imports to one of exerting mutual advantage through imports and exports. The structure of trade in forest products will alter with changes in the forest resource base and with new developments in the forest industry. 相似文献
3.
The Lacey Act of 1900 was amended on May 22, 2008, to prohibit the import of illegally sourced plant materials and products manufactured from them into the United States and its territories, and to similarly ban their interstate transport. Trade theory suggests that the effect of the new law would be to reduce the flow of illegally sourced fiber into the United States, increasing prices. Monthly U.S. import data on tropical lumber (January 1989–June 2013) and hardwood plywood (January 1996–June 2013) quantity and unit value were used to estimate alternative statistical models that quantify the impact of the 2008 Lacey Act Amendment on import prices and import quantities of products from potential source countries. Results show that the Amendment's quantity effects are generally negative and double in magnitude in percentage terms than the price effects, consistent with expectations of the effects of a backwards shift in foreign supply against an elastic import demand. Models indicate that there have been double-digit percentage increases in prices and decreases in quantities of tropical lumber imports from Bolivia, Brazil, Indonesia, Malaysia, and Peru. Similarly large changes in hardwood plywood import prices and quantities from Brazil, Indonesia, and Malaysia have occurred, while smaller, and in some cases statistically insignificant, changes have been observed for hardwood plywood imports from China, Ecuador, and Taiwan. 相似文献
4.
《Scandinavian Journal of Forest Research》2012,27(5):433-442
Abstract This research reports the major evaluation results from an operational stand-based forest inventory using airborne laser scanner data carried out in Norway. This is the first operational inventory in which data from two separate districts are combined. Laser data from two forest areas of 65 and 110 km2 were used to predict six biophysical stand variables used in forest planning. The predictions were based on regression equations estimated from 250 m2 field training plots distributed systematically throughout the two forest areas. Test plots with a size of 0.1 ha were used for validation. The testing revealed standard deviations between ground-truth values and predicted values of 0.58–0.85 m (3.4–5.6%) for mean and dominant heights, 2.62–2.87 m2 ha?1 (9.3–14.3%) for basal area, and 18.7–25.1 m3 ha?1 (10.8–12.8%) for stand volume. No serious bias was detected. For 10 of the 12 estimated regression models there were no significant effects of district. 相似文献
5.
森林认证对森林转型的影响——来自发展中国家的经验证据 总被引：1，自引：0，他引：1
森林转型理论总结了长期以来各国实现森林恢复的影响因素与作用机制。20世纪90年代以来,森林认证作为促进森林可持续经营的市场机制在世界范围内逐渐展开。文中基于1990-2010年76个发展中国家的面板数据,运用分位数回归方法定量分析森林认证对森林转型的影响。研究结果表明,森林认证对森林面积和森林蓄积量都具有显著的正向影响,且在森林资源相对缺乏的发展中国家影响更大;研究还发现,人口密度和人均GDP对森林面积和森林蓄积量具有显著的负向影响,而造林面积、林产品进口额以及非初级产品出口比重等对森林面积和森林蓄积量都具有显著的正向影响。 相似文献
6.
Theodoros Koutroumanidis Eleni Zafeiriou Garyfallos Arabatzis 《Forest Policy and Economics》2009,11(1):56-64
The present paper studies the existence of asymmetry in the price transmission mechanism between the producer and the consumer prices in the sector of forest products. In particular, the research is focused οn the round wood of long length (> 2 m). For the study of the asymmetry, the Johansen cointegration analysis was used while at the same time two dynamic models were estimated: The Error Correction Model (ECM Model), and the LSE?Henry general to specific model (GETS model). With the assistance of the cointegration technique, we surveyed the existence of a long-run relationship between the producers and the consumers in the Greek round wood market, while the application of the Granger causality test has shown that the consumer price Granger causes the producer price whereas the reverse is not valid. Furthermore, the application of the GETS model confirmed the existence of asymmetry in the price transmission mechanism within the round wood market. Finally, the role of imports in the determination of the producer prices is vital and is confirmed by the findings of the cointegration technique and the Granger causality test. 相似文献
7.
lntroductionChina'sterritoryisvast,buttheforestedareaisless.About29%areaofChinaisdesertandbaremOuntains(Zhangetal.1997).ThefourthnationaIforestsurvey,whichwasconductedbytheMinistryofForestryin1989~1993,indicatesthat133.7millionhm2or13.92%oftheIandareaofChinaareforest.Thestockoflivingtreesis11.785bilIionm',ofwhich1o.1biIIionisinforest.Thenetgrowthofstandingvolumeiso.4biIIionm3peryear,whiIethecutisO.3billionm',ofwhichatleastonethirdisfarfueIwood.Sotheforestresourcesarenotrich,forestcoveri… 相似文献
8.
《Forest Policy and Economics》2003,5(2):157-171
The global forest sector model EFI-GTM was applied to assess regional impacts in Europe of increased timber supply caused by potential acceleration of forest growth in Europe. The EFI-GTM is a multi-periodic partial equilibrium model, which contains 31 European regions and 30 regions for the rest of the world, and trade between the regions. The endogenous sectors include 26 forest industry products and six wood categories. Three alternative forest growth scenarios were analysed: a base line assuming the present annual rate of growth in the European countries, and two accelerating growth scenarios corresponding to a 20 and 40% increase after 20 years in the forest growth relative to the baseline growth. In the accelerated growth scenarios equilibrium prices for logs and sawnwood decreased significantly from the baseline levels, whereas the other forest product prices were not affected much. Depending on region and timber category, the log prices in 2020 were 7–9 and 13–17% lower than the base line prices in the medium and high forest growth scenarios, respectively. For sawnwood, the corresponding price decreases were 2 and 3.5–4.5%. In Western Europe, log harvest and sawnwood production increased because accelerated forest growth substituted for imports of these commodities from Russia and Eastern European countries. This decreased the harvests in Russia and Eastern Europe relative to the base case. In all the three forest growth scenarios the forest owners income as well as the forest industry profit increase over time. 相似文献
9.
Rafał P. Chudy Hanne K. Sjølie Greg S. Latta Birger Solberg 《Scandinavian Journal of Forest Research》2019,34(3):218-227
Second-generation biofuels are often seen as essential element in the future bioeconomy strategy. Countries with extensive forest resources such as Norway often view wood as preferred bio-feedstock, yet the effects of wood demand on assortments of harvested wood and other wood-based industries are unclear. Focusing on the importance of feedstock choice, we analyse the impacts of establishing a second-generation medium-scale biofuel plant in Norway. For the analysis, a dynamic forest sector model where the choice of tree species, wood assortments, production of bioenergy, and forest industry products are explicitly included, was applied. We find the optimal biofuel feedstock mix to be dominated by softwood chips from pulpwood comprising 48% of total biomass inputs in 2030 and increasing to 67% by 2055, followed by hardwood chips from birch, comprising initially 34% of total biomass inputs and 16% by 2055. The proportion of harvest residues remained constant at about 18% over time and roundwood was not used at all for biofuel production. Despite the additional demand for chips, the single medium-scale biofuel plant will have only minor effects on existing forest industries and harvests in Norway, as the domestic impact is dampened by changes in foreign trade flows, especially of chips. 相似文献
10.
Trade barriers of forest products are often advocated in the name of protecting forest resources. Whether the promoting of trade of forest products will increase or decrease the global forest resources is still a matter of debate. We offer an assessment of how forest product trade helps shape observed forest change, by relating wood consumption change to trade of forest products based on cross-section data from 61 countries in 2010. The result shows that wood outputs have positive effects on wood consumption. Compared to domestic production, the result suggests that imports of forest products can help reduce wood consumption. This may indicate that trade liberalization can promote the allocation efficiency of timber resources across the global, which can improve the utilization efficiency and reduce the wood consumption in the world to protect the global forest resources. It is suggested that the high-efficient harvest and wood-processing technological transfer should be advocated in the international community to contribute to global forest conservation. 相似文献
11.
中美贸易摩擦是中美经济关系中的重要问题。2018年中美贸易摩擦爆发后,双边经贸关系曲折不断,木质林产品贸易面临极大考验。文中在梳理2015—2020年中美双边木质林产品贸易数据的基础上,分析贸易摩擦对双边木质林产品贸易的影响。结果显示,中美贸易摩擦对双边贸易规模具有较大影响,贸易总额、进口额和出口额均大幅下降;木家具和人造板等木质林产品贸易受到较大冲击,双方短期内均难以找到替代市场;中国从美国进口原木和锯材大幅下降,但中国木材供应和木材安全未受到威胁。未来,建议从增加国内木材供应、拓展替代市场、优化林业产业结构、建立国际国内双循环的林产品市场方面积极应对贸易摩擦。 相似文献
12.
Technical change is developing rapidly in some parts of the forest sector, especially in the pulp and paper industry where wood fiber is being substituted by waste paper. In forest sector models, the processing of wood and other input into products is frequently represented by activity analysis (input–output). In this context, technical change translates in changes over time of the input–output (I–O) coefficients and of the manufacturing cost (labor, capital, and materials, excluding wood and fiber). In the case of the global forest products model, the I–O coefficients and the manufacturing costs are determined empirically from historical data, while correcting for possible reporting errors. The method consists of goal programming. The objective function is the sum of the weighted absolute value of the deviations from estimated and observed production in each country of interest. The constraints express the relationship between the multiple output (sawnwood, panels, pulp, paper) and input (wood, waste paper, other fiber) and prior knowledge on the limits of the I–O coefficients. The paper presents observed technical changes from 1993 to 2010 and projections to 2030 with their consequences for the global forest sector in terms of prices, production and consumption, value added, and carbon sequestration in forest biomass. 相似文献
13.
《Forest Policy and Economics》2000,1(1):27-40
This paper addresses the effects of economic transition policies on forestry in China. The effects of de-collectivization and market liberalization on the forest land area and timber harvest are studied using panel data from four provinces covering the period 1978–1995. Fixed effects ordinary least squares models for forest land cover and annual harvests per hectare are estimated, allowing for differences across provinces and prefectures in northern and southern China. The results show that land tenure reform in general has had a positive effect on forest land expansion, but the absolute size of the effects varies from province to province. The positive impact of the reform on timber harvesting has not taken place at the cost of forest land cover. The claim that market liberalization leads to over-harvesting of forest resources in developing countries is not supported by our results. 相似文献
14.
The consumption of wood and wood products in Greece is based greatly on imports necessitating every year a great proportion of public expenditures. The study of wood and wood product imports consequently, is important to the national economy and can be a useful guide for the forest farms, wood industries and wood firms. In this paper the Greek aggregate import demand for Unprocessed wood (such as logs) Processed wood (such as sawn wood), Veneer Crafts (such as veneer sheets) and Wood Manufactures during the period 1969–2001 is empirically analysed using the linear approximation of quadratic AIDS (QUAIDS) model. Imports of Unprocessed wood, Veneer Crafts and Wood Manufactures are found to be price-elastic, in contrast to Processed wood imports. Processed wood, Veneer Crafts and Wood Manufacture imports are found to be expenditure-elastic while Unprocessed wood is found to be an inferior good. Substitution possibilities are found to be significant between Veneer Crafts and all the remaining wood imports and between Processed wood and Unprocessed wood. 相似文献
15.
16.
《Forest Policy and Economics》2003,5(3):297-304
Patterns in forest products trade between European Union and Central and Eastern European access candidates were studied. The results indicated that both production and trade of forest products in Central and Eastern European countries in transition have considerably increased during the 1990s. The European Union has been the most important trading partner for CEE countries, even though the EU share from the external trade has been quite stable. The gravity models estimated explained approximately 66% of the variation in volume of bilateral trade flows in EU and CEE countries in 1997. Results indicated that trade between EU and CEE countries was below the level that would be expected on the basis of income and distance. A model separating the trade flows according to direction suggested that this is due to the low intensity of West–East trade, which probably originates in low levels of consumption of higher value-added products in CEE countries. East–West trade did not significantly differ from the average pattern. 相似文献
17.
Interferometric Synthetic Aperture Radar (InSAR) data from TerraSAR-X add-on for Digital Elevation Measurement (TanDEM-X) were used to estimate aboveground biomass (AGB) and tree height with linear regression models. These were compared to models based on airborne laser scanning (ALS) data at two Swedish boreal forest test sites, Krycklan (64°N19°E) and Remningstorp (58°N13°E). The predictions were validated using field data at the stand-level (0.5–26.1 ha) and at the plot-level (10 m radius). Additionally, the ALS metrics percentile 99 (p99) and vegetation ratio, commonly used to estimate AGB and tree height, were estimated in order to investigate the feasibility of replacing ALS data with TanDEM-X InSAR data. Both AGB and tree height could be estimated with about the same accuracy at the stand-level from both TanDEM-X- and ALS-based data. The AGB was estimated with 17.2% and 14.6% root mean square error (RMSE) and the tree height with 7.6% and 4.1% RMSE from TanDEM-X data at the stand-level at the two test sites Krycklan and Remningstorp. The Pearson correlation coefficients between the TanDEM-X height and the ALS height p99 were r?=?.98 and r?=?.95 at the two test sites. The TanDEM-X height contains information related to both tree height and forest density, which was validated from several estimation models. 相似文献
18.
The effect of changes in roundwood harvests in Norway on the harvests in rest of the world is examined using a global forest sector model. About 60–100% of the harvest change in Norway is offset by an opposite change in the rest of the world. Such leakage rates vary over time, wood category, background scenario, and the size of the harvest change. Asymmetries between the effects of increasing and decreasing the harvests also exist. Hence, the magnitude of leakage rate is case specific, though considerable. Under tightening wood supply there is less need/room to respond to harvest increase/decrease in Norway with incremental/reduced harvests elsewhere. When the use of global forest resources intensifies with increasing wood demand in the future, leakage rates can be smaller than today. It is important to account for harvest leakage in order to avoid overestimating the climate benefits of policies that decrease or increase roundwood harvests. For instance, for full carbon sequestration benefits of increasing harvests for harvested wood products, creating fresh additional demand for these products should be prioritized. Else the origin of raw material and the place of production for these products may change instead of their stock. 相似文献
19.
ABSTRACT This study applied a gravity model estimation using panel data in order to analyze the impact of the determinants of Vietnam’s wood products trade from 2001 to 2016.The gravity estimates imply the importance of size of the economies, distance, level of openness of the economy, population, forest resource endowments of Vietnam’s trade partners, Vietnam’s logging restrictions policy, common border, free trade agreement, and exchange rates as determinants of Vietnam’s wood products trade. These variables were found to have different effects on the export and import of wood products. Vietnam’s access to the WTO and APEC did not help either its imports or exports in wood products. The results of this study also indicate that the Government of Vietnam needs to implement policies to increase investment in the wood processing industry, develop high quality wood materials from domestic plantations, and take advantage of trade preferences from new free trade agreements in order to promote wood product trade. The results of this study have implications for trade policy, resource-based economic development, and Vietnam’s forest resource conservation. 相似文献