中俄木材贸易对中国实木加工业的影响

俄罗斯是我国木材的主要供应国,今年6月1日俄罗斯正式提高原木出口关税,这将对我国原木进口产生一定的影响,同时也会对以俄罗斯原木为主要原材料的生产商产生一定的影响.本文旨在探讨新税法实行后,俄罗斯木材供应的变化以及对我国实木加工业的影响.主要分为四部分,我国木材供需现状、俄罗斯的木材资源、中俄木材贸易现状和趋势、中俄木材贸易对中国实木加工业的影响.     

中国原木进口贸易的时空演变、发展困境与趋势展望

文中基于1997-2019年中国原木进口贸易数据,分析中国原木进口贸易的动态特征及时空格局演变,揭示当前中国原木进口贸易的发展困境,提出促进中国原木进口贸易持续健康发展的对策建议。从进口贸易的动态特征看,中国原木进口贸易规模较大且进口比重逐年增高,进口依存度不断提升,进口价格不断波动。从进口贸易的时空格局演变看,中国原木进口的地理方向不断扩张,进口来源逐渐向多元化方向演变。同时,中国原木进口面临对外高度依赖下的价格议价权缺失、原木出口国限制政策频繁出台致使进口受阻和运输成本偏高等困境。新时期,优化原木进口贸易,除了加强国内森林资源储备、提升国内木材供给能力外,应通过成立木材进口企业联盟提升中国木材进口议价权,通过全方位的合作政策拓展木材进口来源多元化,并以"一带一路"倡议为契机,拓宽原木进口通道,降低运输成本,提升利润空间,推动中国原木进口贸易持续健康发展。     

中俄木材贸易对中国实木加工业的影响

俄罗斯是我国木材主要供应国,今年1月1日俄罗斯正式提高原木出口关税,这将对我国原木进口产生一定的影响,同时也会对以俄罗斯原木为主要原材料的生产商产生一定的影响,本文旨在探讨新税法实行后,俄罗斯木材供应的变化以及对我国实木加工业的影响.主要分为四部分:我国木材供需现状、俄罗斯的木材资源、中俄木材贸易现状和趋势、中俄木材贸易对中国实木加工业的影响.     

中俄木材贸易对中国实木加工业的影响

俄罗斯是我国木材主要供应国,今年1月1日俄罗斯正式提高原木出口关税,这将对我国原木进口产生一定的影响,同时也会对以俄罗斯原木为主要原材料的生产商产生一定的影响,本文旨在探讨新税法实行后,俄罗斯木材供应的变化以及对我国实木加工业的影响.主要分为四部分:我国木材供需现状、俄罗斯的木材资源、中俄木材贸易现状和趋势、中俄木材贸易对中国实木加工业的影响.     

中俄木材贸易对中国实木加工业的影响

俄罗斯是我国木材主要供应国,今年6月1日俄罗斯正式提高原木出口关税,这将对我国原木进口产生一定的影响,同时也会对以俄罗斯原木为主要原材料的生产商产生一定的影响,本文旨在探讨新税法实行后,俄罗斯木材供应的变化以及对我国实木加工业的影响.主要分为四部分,我国木材供需现状、俄罗斯的木材资源、中俄木材贸易现状和趋势、中俄木材贸易对中国实木加工业的影响.     

市场回归理性,供求趋向平衡——2012年我国木材进出口情况评析(二)

一.2012年我国木材进口的基本情况1.2012年我国木材市场总体格局和运行态势,出现了与2011年明显不同的特征。2.2012年我国木材进口总量同比出现下降。3.2012年我国木材进口总量出现下降,主要是针叶原木进口量出现大幅下降。4.从针叶原木主要进口来源国看,     

对进口美国原木及其检验刍议

一.进口木材应是我国的一项长远政策进入80年代,为了适应经济增长的需要,弥补国内资源不足,木材进口量迅速增加,使我国成了世界上居日本之后的第二大木材进口国。进口的木材产品有原木、锯材、胶合板、纸浆和纸产品等,其中以原木为主。原木进口在1985年和     

2008年上半年我国进口木材市场分析

今年上半年我国进口原木数量开始以较大幅度下降,进口锯材数量增幅也变缓。原木和锯材是我国林产品进口中的大宗商品,近年来均以较高的增速连年增长,而今年上半年进口额大幅度下降的趋势,必将对我国的木材进口企业和木材加工企业产生较大的影响,应引起我国木材行业的高度重视。     

2011年我国林产品进出口开门红

2011年我国林产品进出口实现开门红,木材进口和人造板及木制家具等出口有明显增长. 一、今年我国原木、锯材、刨花板和木质家具进口大幅度增长 随着国民经济的发展,市场对各种木制品需求量不断增大,加上各种林产品出口大幅度增长,使木材加工业的木材消费量增大,带动原材料的进口.     

2012年1季度我国木材进出口情况点评

一、2012年1季度我国木材进口基本情况随着宏观经济面的变化,今年1季度我国进口木材情况出现了与前3年显著不同的特点。1.今年1季度我国木材进口总量同比出现下降。今年1季度我国进口木材原料（包括原木、锯材、薄板、胶合板、纤维板、     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.     

CAD与建筑设计的关系

本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。     

Natural Regeneration in Clear-cuts: Effects of Scarification,Slash Removal and Clear-cut Age

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided.     

Risk Perception Among Non-industrial Private Forest Owners

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.     

Interactions in decomposition and N mineralization between tropical legume residue components

In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.     

Pasture production and tree growth in a young pine plantation fertilized with inorganic fertilizers and milk sewage in northwestern Spain

The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization, (2) milk sewage sludge at 40 kg N ha⁻¹ target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha⁻¹. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹); (2) Lolium perenne L. var. Tove (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea (Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m², with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral systems. This revised version was published online in June 2006 with corrections to the Cover Date.