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1.
Pulpwood is imported to Sweden as a result of price discrimination and the monopsonistic features of the domestic pulpwood market. To investigate the determinants of Swedish pulpwood imports, econometric models were developed for the three imported assortments: pine, spruce, and non‐coniferous pulpwood. All prices used in the models were relative to the price of pulpwood imports. The study shows that the relative price of pulpwood (e.g. price of standing timber for sale/price of pulpwood imports) is not a significant determinant of pulpwood imports; it has the wrong sign for spruce pulpwood. This unexpected finding may have been a result of the impossibility of categorizing the price for standing timber according to pulpwood assortments. The relative export price of pulp, however, was found to be a significant determinant of spruce pulpwood imports, although not of pine and non‐coniferous pulpwood. An important determinant is the relative prices of inputs other than pulpwood in pulp production. The study also shows that pulpwood imports respond to price signals with a 1 yr lag, indicating inertia in trade.  相似文献   

2.
This paper tries to reconcile casual empiricism of what has been happening in the pulpwood market in Sweden with a stochastic version of the theory of monopsony. This means that the firm, which is using wood as an input in production, has to make a price and/or quantity decision before the actual supply curve of pulpwood is revealed. We show that excess demand tendencies are to be expected, if the production function is close to linear in the wood input. We also show that pricing behavior and stochastic supply can explain why the paper and pulp industry often produces at a lower level than full capacity utilization.  相似文献   

3.
This paper presents a short‐term econometric model for the sawlog and pulpwood markets in Finland. More specifically, the effects of structural changes in the market on the success of short‐term market modelling are investigated. Wood prices and quantities traded are stationary. Therefore, valid statistical inference using the levels of these variables is possible. Pulpwood prices were found to be directly proportional to sawlog prices during the study period, and the cross‐price effects were not statistically significant. The results indicated that the price sensitivity of wood supply in Finland increased during the 1980s and early 1990s. Nationwide collective price agreements were found to have increased the level of pulpwood supply and demand from private forests, but to have had no effect on either supply of or demand for sawlogs. Due to a structural change in the 1970s, the models estimated for the whole period cannot be used for short‐term forecasting in the 1990s. Higher‐than‐annual frequency data should be used in developing accurate short‐term forecasting models.  相似文献   

4.
Abstract

A partial equilibrium forest sector model which is augmented to include bioenergy was applied to project the use of bioenergy based on forest fuels and forest industry by-products in Norway for three different scenarios of the future prices of electricity and oil. The impacts on forestry and forest industries of the different energy price scenarios were also studied. The advantage of the suggested methodology is that it allows for assessments of the economic potential of bioenergy, taking into account the competition for raw materials, the specific heat demand of various regions, and interregional and international trade. Bioenergy will, according to this study, be fairly competitive in some market segments with the current price levels of electricity and oil, and only a minor increase (decrease) in energy (roundwood) prices would release substantially increased bioenergy production levels. Pulpwood prices of pine and non-coniferous species are projected to increase substantially when assuming increasing energy prices. Except for particleboard mills, production levels of forest industries appeared relatively insensitive to the energy price changes.  相似文献   

5.
A partial equilibrium model was applied to the global forest sector in order to assess regional and global impacts of changes in economic growth, timber supply potentials, and technical trends. The model uses recursive price-endogenous linear programming and deals with eight geographical regions and 16 products. The base line projections of the model gave an average annual increase in global supply of industrial roundwood of 1.2% until the year 2010. The real price of sawlogs and sawnwood was found to remain approximately constant, whereas the prices of pulpwood and particles increased significantly during the first years, and then declined after the year 2000. The real prices of pulp and paper increased less than those of pulpwood and particles. The assumed variations in GDP growth rates had limited influence on quantities supplied and traded due to restricted timber supply potentials, but affected the real prices, especially of pulpwood and particles. Changes in the assumed timber supply potentials and technical change affected the real prices of pulpwood and particles significantly. Introduction of a price responsive timber supply also dampened the price peaks of pulpwood. Possible improvements of the methodology include empirical estimation of timber supply and of key parameters that determine capacity expansion, trade inertia, and technical changes.  相似文献   

6.
This paper provides an analysis on the integration of prices for imported coniferous pulpwood and sawlogs, and respective domestic stumpage prices in the Finnish wood market. Eight real price series were investigated during 2002–2014 using monthly observations. The bounds testing approach by Pesaran et al. [(2001) Bounds testing approaches to the analysis of level relationships. J Appl Econom. 16: 289–326. doi:10.1002/jae.616], indicates there are long-run relationships between prices of domestic and imported wood. For more detailed information, the vector error correction model (VECM) approach was used. Estimation of a system with all eight prices with interpretable results did not succeed; therefore, we estimated models for prices of sawlogs and for pulpwood separately. For sawlogs, two co-integrating vectors, one for pine and one for spruce, were found. For pulpwood prices, one co-integrating vector was identified. The estimated VECMs confirm the results of bounds testing approach, suggesting that causation in the Finnish wood market runs from domestic prices to prices of imported wood. We conclude that prices of domestic and imported coniferous logs and pulpwood are closely connected. The question of full integration remains open, as border prices and stumpage prices by definition differ, at least, by logging and transportation costs.  相似文献   

7.
以定向、速生、丰产、优质、高效为目标,研究了长白落叶松纸浆材人工林不同种源、苗木和立地条件对生长的影响,同时通过对长白落叶松数量成熟龄、工艺成熟龄和经济成熟龄的研究分析,确定了长白落叶松纸浆材轮伐期。  相似文献   

8.
During the early eighties farmers in north-west India planted Eucalyptus on a massive scale for sale as poles and pulpwood. However, after 1986 farmers in this region have almost stopped growing Eucalyptus, as their experience with its marketing was not a happy one. The pole market got saturated, paper mills did not pay a remunerative price, and fuelwood prices were low and uneconomical. More important, because of legal restrictions on the transport and sale of wood, and other institutional factors, the gap in the farmgate price and the consumer price remained very wide. Wood markets have, on the whole, exploited the farmers, rather than helped them. Due to this, the short period of flirtation with tree crops seems to be over for at least resident farmers in those very areas in north-west India where they had so enthusiastically planted Eucalyptus in the early 1980s.Abbreviations BDO Block Development Officer - Headloaders poor people who collect firewood on their heads from forest lands for consumption and sale - m ha million hectares - Rs Indian Rupee 16 Rs = 1 US Dollar in 1989 - panchayat elected village organisation - pradhan village chief On study leave from the Government of India to the Oxford Forestry Institute, South Parks Road, Oxford, OX1 3RB, U.K. Present address: 17 Ponnappa Road, Allahabad 211001, India  相似文献   

9.
SINDEN  JOHN A. 《Forestry》1965,38(2):201-217
The economic principle, which was presented in an earlier paper(Forestry, 37, 161), is developed into a flexible techniqueof economic analysis for use in forest management. The techniqueprovides a rapid method for analysis of the marginal decisionon financial rotation length; whether to fell now, or in fiveyears or so. The developments include incorporation of a price-sizegradient, different product prices, various costs of operation,reductions in volume yield, and various establishment and maintenancecosts. Now in its final form, it can incorporate these changesin stand conditions without any laborious calculation. The techniqueis used to analyse the effect of financial factors on the marginaldecision, i.e. prices, costs, and productivity. It is suggestedthat financial rotations are fundamentally dependent on therelation between physical production and the interest rate.Second, establishment and annual maintenance costs have no effecton the decision. Third, prices, or more specifically the ratioof pulpwood price:sawtimber price, are not of major importance,because they influence the decision within the limits alreadyimposed by production and interest rates. The justificationfor pulpwood rotations is also examined. This paper has developeda basic technique for projects of forest economics. It is partof the research work into the economics of timber production,which is being undertaken by the author at the Forestry Department,University College of North Wales, Bangor.  相似文献   

10.
专用纸浆材遗传育种现状及思考   总被引:1,自引:0,他引:1  
当今,纸浆材树种由过去的针叶树种为主体转向针、阔树种协调发展;良种选育由过去只注重提高纤维产量向产量与制浆品质并重方向发展;育种技术向杂交育种和基因工程方向发展。作者在综述国内外纸浆材遗传育种现状和我国发展纸浆材基地政策基础上,提出了短周期优质纸浆材育种策略、育种程序、技术路线、研究内容和育种指标。  相似文献   

11.
“云南松胶合板材、纸浆材种源选择”是多性状综合评选,把生长与多用途选育结合。本材料取自1981年营造的种原试验林和部分天然林内,共选取13个产地,38件试材,作木材解剖,物理性能和化学成分含量等测定.经分析各种源间木材的各理化性状的差异达权显著水平.并获得与胶合板、纸浆材关系较密切的是种源间年均材积生长量(X1)、树干纹理通直度(X2)、木材密度(X3)、管胞长(X4)、纸浆得率(X5).根据性状遗传力(H2)及它们的经济重要性估算权重值(W),建立“两材”的种源综合选择指数方程:①I板=214.0571X1+0.29859X2+0.37736X3和②I纸=214.0571X1+0.06212X4+0.39278X5。按①和②综合选择式,评选出乐业、红河、双柏、双江、石屏、开远、富宁等8~10个适于“两材”高产优质种源,材积平均遗传增益达47.3%,树干纹理通直率达87%~98%;单位面积上木材干物质重提高18.0%~49.6%,纸浆得率18.4%~49.7%。胶合板的抗压、抗弯强度等力学指标均有提高,胶合强度1.97~2.58MPa>0.8MPa(GB指标),手抄纸的耐破度,裂断长,撕裂度均达到观指标。使“两材”的种源选择建立在遗传型的基础上.同时为各生态区提出供选择的丰产种源。  相似文献   

12.
The differentiation process including somatic embryogenesis in different Ginkgo explants in vitro culture were studied by cytological observation.The results are as follows:1) two complete cotyledons and a embryo bud were observed in mature embryos and several secretory acavitives appeared in maturation region of embryo buds,hypocotyls,cotyledons and radicles after culturing 20 days;two incomplete cotyledons and a embryo bud primordia were found in large cotyledon embryos.The proembryo of two cells,four cells, multi-cellular,and globular embroy were developed from the callus of the small cotyledon embryos.2) The differentiation of cotyledon explants started from epidermal cells,and gradually formed meristematic cell mass in the cortical cells,and eventually adventitious buds were observed.3) The adventitious roots of Ginkgo originated in the cells at the cross of vascular cambium and vascular rays. 4) The type of rooting belongs to induction type by root primordium.The formed adventitious roots were observed after 20 days.  相似文献   

13.
This paper develops a simple two‐period present value maximizing model of forest management. The production possibility is determined by the initial forest endowment, a growth function and transformation relations between thinnings, final fellings, pulpwood supply and sawtimber supply. The model is applied on thinnings and final fellings data of three different ownership categories in Sweden; private industrial, private non‐industrial and public owners. The results show lower price elasticities than previous studies where no distinction between ownership categories are made. Also, a previously unused inventory variable seems to have an important explanatory power.  相似文献   

14.
Abstract

This study examines price dynamics in roundwood exports from Russia to Finland, the largest international roundwood trade flow within Europe. The analysis covers six main timber assortments; sawlog and pulpwood dimensions of pine, spruce and birch. The study period, starting from the devaluation of the rouble in August 1998, was characterized by a drastic increase in the volumes of Russian roundwood imported into Finland, and a coinciding structural change in the timber assortment distribution of the Finnish roundwood imports. A basic hypothesis of economic theory, the law of one price, was tested by using quarterly time series and methods of cointegration analysis. According to the cointegration tests, the prices of Finnish and Russian spruce sawlogs have moved closely together. Furthermore, the changes in the prices of spruce sawlogs in the Finnish roundwood market are reflected in the Russian prices and not vice versa. Regarding other timber assortments, price co-movement and consequent market integration was not detected.  相似文献   

15.
We used the portfolio method to examine how a forest company can lower investment risk by producing a mix of timber products. We derived optimum combinations of pine (Pinus patula) saw timber production and eucalypt (Eucalyptus grandis) pulpwood production at landscape level. Our results indicate that producing a product mix rather than a single product improves aggregated financial returns and lowers investment risk over multiple rotation periods. The optimum mixture depended on past timber price correlations for pulpwood and sawn timber in South Africa between 1980 and 2011. This ideal mixture is comprised of areal ratios of about 45% saw timber and 55% pulpwood. Our example shows how economic risk of a forest investment can be reduced by creating a portfolio of a number of products. The risk that an investor has to accept for each monetary unit that is expected in return can be reduced by over 40% when comparing the risk–return combinations of a pure pine saw-timber stand with that of a portfolio of forest products. The risk associated with the production can be reduced by 20% when growing a portfolio of products rather than eucalypt pulpwood only.  相似文献   

16.
华南地区桉树可持续遗传改良与育种策略   总被引:12,自引:5,他引:12       下载免费PDF全文
从华南地区发展桉树工业纤维用材林对高产、优质、抗逆新品种需求的迫切性出发,分析了桉树引种成功之后遗传改良现状和存在问题,提出要实现华南桉树人工林可持续经营,必须建立和完善桉树长期可持续遗传改良体系,坚持以多世代群体遗传改良为基础,种间杂交无性转化利用为突破,加快育种增益转化为生产力的育种思路;强调新世纪桉树育种要重视常规育种与分子遗传研究相衔接,通过群体、个体、细胞和分子多层次多育种方式的相互交叉,充分利用各层次的遗传变异,提高育种效率。  相似文献   

17.
纸浆材人工林复合轮伐期的讨论   总被引:1,自引:0,他引:1  
针对我国纸浆材人工林的经营现状和存在的问题,本文提出了复合轮伐期的概念。纸浆材人工林实行复合轮伐期经营的材积收获量,将比单一轮伐期经营高出20%,再加上复合轮伐期生产的大径锯材市场价格高的因素,相应的经济收益将高出更多。复合轮伐期充分利用了地力和林木生长的潜力,它不仅是纸浆材轮伐期和大径锯材轮伐期的复合,也是经营目的的复合,体现了现代林业多目标培育林木的经营原则。  相似文献   

18.
This study presents an econometric analysis of the spatial integration of the Nordic timber market as reflected in timber prices. The statistical model is a vector autoregressive (VAR) model with cointegration. The degree of spatial integration is tested through a cointegration analysis and a complete identification of the statistical model's long‐run structure. When the results were interpreted in terms of factor price equalization and efficient commodity arbitrages, the Nordic markets were found to be strongly integrated. The pattern of interdependence is investigated through an analysis of the model's short‐run structure and interpreted in terms of Granger causality. Finland, and to some extent Sweden, were found to act as “price‐leaders” in the long run and Denmark and Norway were very sensitive to changes in timber prices in competing countries.  相似文献   

19.

Recent increases in pulpwood imports to Finland have raised an intense debate about their possible effects on the domestic wood markets. Since important institutional and structural changes in the market environment have taken place in the markets during the 1990s, it is important to take these into account in modelling imports. Our results consider three different time periods between 1986 and 1998, and indicate that market mechanisms in Finnish birch pulpwood imports have improved substantially in the latter part of the 1990s. Imports are found to be elastic with respect to changes in pulpwood import price, domestic pulpwood price and pulp export price. Furthermore, imports of birch pulpwood seem to have complemented the domestic market rather than to have been a substitute for it.  相似文献   

20.
鲁林3号杨,雄株,是以美洲黑杨I-69为母本,美洲黑杨PE-3-71为父本,经人工控制授粉,对杂种F1代进行苗期筛选和无性系造林试验选育而成.具有易繁殖、速生、材质优良、抗病虫和抗逆性强等特性,是优良的杨树工业用材树种,适宜培育胶合板材和纸浆材.  相似文献   

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