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小径材和采伐加工剩余物的利用途径及工艺吴萌（西北林学院）随着木材采伐工业的发展，成过熟林日益减少，小径材生产比例显著增加。人工林的大力发展和次生林的更新改造，也使小径材数量迅速增长。另外据统计，林区采伐剩余物约占采伐量的３８％～４０％，加工剩余物约占... 相似文献
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大兴安岭林区每年有采伐、造材、加工剩余物和次加工小径木、薪炭材共计约200万立米,对这部分木材的有效利用,是当前急待解决的重要课题.笔者就大兴岭林区利用木材剩余物和次小薪材发展造纸工业,开拓林纸结合基地略谈浅见。一、实行林纸结合的必然趋势1、从原料基地到造纸的一条龙生产,是发达国家林业造纸所走的共同道路.如美国惠好和维斯特瓦柯公司都是林纸综合经营的企业,是从营林、造林、采伐、制材、制浆、造纸和其它木制产品的生产、销售,形成了生产与经营的有机整体,可最大限度地 相似文献
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2004年1月27日新西兰森林工业信息中心消息：为减少国家森林火灾，布什政府正寻求利用小径木和灌木生产能源副产品，用来负担森林疏伐的费用。美国西部有1134万hm^2森林，森林火灾的危险性极大，但森林作业费用一直是个难题，因为需要疏伐的树木较小，无法用做锯材。现在计划将这些采伐剩余物加工成乙醇、甲醇和其它生物产品。 相似文献
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采伐剩余物是木材综合利用的主要原料,占木材工业剩余物的82%,其中可挑选出小径木20.1%,用于削片生产的枝丫灌木71.6%。因此加深对木材剩余物利用的研究,对缓解木材供需紧张的矛盾,摆脱林业“两危”有重要意义。一、历史沿革及当前存在的问题采伐剩余物(枝丫材),一般包括树枝、梢头木、摔断木、小杆、被砸坏的小径木、倒木、非目的树种中有利用价值的木材等。总之,伐区内砍倒的或砸坏的树 相似文献
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研究并设计了一种适用于林区的自行式剥皮削片联合机,其主要由行走、剥皮、削片和辅助支撑等装置组成,通过柴油发电机提供动力,满足进给、剥皮与削片的动力要求。该机能适应林区生产环境,可就地将小径材及采伐剩余物加工成不含树皮的优质木片,既节省了人工,又降低了运输成本。 相似文献
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卡列斯捷茨林业局、卡列里和卡尔巴茨木材采运工作者、基洛夫应用技术情报局、波普卢依斯克纤维板厂和水解厂等,研究从灌木林中获得林产品的试验证明:小径木和伐区剩余物对纤维板和水解生产是完全合格的原料(是对基本原料的补充).但是,小径木和伐区剩余物应该首先加工成工艺木片才能利用. 化学和化学机械加工的原料来源,可从 相似文献
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中国林木剩余物数量估算 总被引：1，自引：0，他引：1
《中南林业科技大学学报(自然科学版)》2017,(2)
文中将林木剩余物归纳为林木采伐与造材剩余物、木材加工剩余物、竹子采伐及其加工剩余物、林木抚育间伐物和废旧木材五大类。通过对已有估算方法的发展,系统地给出了各类林木剩余物数量估算方法,进而,通过文献考证,给出了各类林木剩余物数量估算所必须的参数值,包括商品材出材率(81.27%)、经济材出材率(77.17%)、非立木剩余物数量相当于立木材积量的比重(50%)、木材加工剩余物比重(60%)、竹枝叶重量相当于竹材重量的比重(38.07%)、竹材加工剩余物比重(62%)、废旧木质品回收率(65%),以及平均木材气干密度(0.618 t/m3)、单位数量竹子重量(150 t/万根)、木制品和直接用原木使用寿命(12年)。同时通过调研给出了经济林产柴率,并将南方山区、平原丘陵区、北方山区分别取值为8 500 kg/hm2、8 500 kg/hm2和7 500 kg/hm2;以方法研究和参数考证为基础,利用国家林业局森林资源清查结果和林业统计数据基础数据,估算出2013年全国林木剩余物总量为30 284万t,其中林木采伐与造材剩余物4 711万t,木材加工剩余物1 492万t,竹子采伐及其加工剩余物2 817万t,抚育间伐剩余物20 544万t,废旧木材可回收量720万t。 相似文献
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综合利用木材剩余物值得注意的几个问题 总被引：1，自引：0，他引：1
木材剩余物,它包括采伐后的枝丫、树梢、树皮、树叶、树根及藤条灌木的采伐剩余物;制材截头的剩余物;加工后的板皮、板条、木竹截头、锯沫、碎单板、木芯刨花、木块边角余料的加工剩余物;材质低于针阔叶树加工原木最低等级但具有一定利用价值的次加工材，长度在2米以下或径级8厘米以下的小原木、松木干、杂木干、短原木的小径材和薪材等。 相似文献
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谈伐区削片与工厂削片 总被引：2，自引：0，他引：2
一、国外概况世界的森林资源逐年减少,造纸材供应日益紧张,为增加造纸和人造板原料来源,六十年代初国外迅速崛起新兴的森林工业体系——林区木片工业.即将林区的采伐剩余物、营林剩余物、加工剩余物和造材剩余物等加工成工艺木片,作为造纸和人造板的原料.由于它能大大提高木材利用率,增加木材产量,因而受到各国极大的重视. 林区的木片生产主要有两种方式:伐区 相似文献
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云南省中低产林改造剩余物的利用现状和发展前景 总被引：1，自引：0，他引：1
杨婉珊 《内蒙古林业调查设计》2011,(5):118-120
云南省计划进行400万hm^2的中低产林改造任务,改造过程中将必然产生巨量的采伐剩余物。林业采伐剩余物的高价值利用将越来越重要。文章阐述了云南林业采伐剩余物开发利用现状,并对将来林业采伐剩余物的开发利用的前景做了展望。 相似文献
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根据山区劳动力不断减少和林业作为生态建设主体的要求，提出了阔叶林采伐迹地的省力化更新方法。试验表明，阔叶林采伐迹地，不炼山、不整地，充分利用林地原有植株的天然更新能力，只经过定向抚育改造，比重新营建人工林可减少人工75～93工／hm^2，节约成本3615～3990元/hm^2，并减轻了营林过程中造成的水土流失。省力化更新幼林林分生长量大，干材产量是重新人工造林的2．60倍；改造后第6年间伐，间伐材作香菇栽培基质用材利用。保留阔叶树种2500～3000株／hm^2培育大径材，12年生年生长量与对照杜英人工林、杉木人工林相当，但林地的生物多样性得到了较好保护。 相似文献
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A forest biomass yield table based on an empirical model 总被引：1，自引：0，他引：1
Tomohiro Nishizono Toshio Iehara Hirofumi Kuboyama Miki Fukuda 《Journal of Forest Research》2005,10(3):211-220
We report an empirical model for estimating unutilized wood biomass, and its application to Cryptomeria japonica D. Don and Larix kaempferi in Tohno City, Iwate Prefecture, northeast Japan. Outputs from the model are the quantity of unutilized wood biomass and merchantable volume produced by timber harvest. The unutilized wood biomass is divided into stumps, tops, branches, foliages, small trees, and unutilized stems due to their defects. Inputs to the model are mean diameter at breast height (DBH), mean tree height, trees per unit area, and timber utilization standards. DBH distribution, DBH–height curve, stem form, bark thickness, and relationship of stem biomass to foliage and branch biomass could be described by the proposed model, indicating its validity. The proposed model enables us to develop the forest biomass yield tables modified from the existing stem volume yield tables. The developed forest biomass yield tables indicated that the unutilized wood biomass due to defects accounted for the largest part of the whole unutilized wood biomass, and that the ratio of unutilized parts in stem volume to total stem volume could vary with stand age and site productivity class. Based on a comparison of the developed forest biomass yield tables with those reported previously, we concluded that the proposed model-based forest biomass yield table would be useful for estimating the quantity of unutilized wood biomass. 相似文献
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Guofang Wu Enchun Zhu Yong Zhong Yingchun Gong Haiqing Ren 《Journal of Wood Science》2018,64(4):356-363
Small diameter logs from juvenile trees are heavily produced during the management of artificial forests around the world. As a kind of plentiful and inexpensive natural resource, the potential was not fully explored. So far the small diameter logs are mainly used as raw materials for products other than building materials. To utilize these small diameter logs originating from juvenile trees as structural members into wood construction, a kind of hybrid built-up column was developed and the performance was investigated experimentally and theoretically. It was found that column had good load-carrying capacity. To apply the developed member in wood construction, the prediction method of the column was proposed. The effective slenderness ratio which took the shear deformations due to the bending of limbs and slip of nail connections between U-shaped nails and limbs into consideration was derived based on mechanics theory. The proposed prediction method was found to have good accuracy in predicting the load-carrying capacity of the hybrid built-up column. This paper can promote the structural application of the small diameter logs originating from juvenile trees. 相似文献
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Small-Scale Timber Harvesting: Mule Logging in Hyrcanian Forest 总被引：1，自引：1，他引：0
Meghdad Jourgholami 《Small-Scale Forestry》2012,11(2):255-262
Animal-powered logging is a labour-intensive operation. Mule logging is still performed in the Hyrcanian forest ecoregion in Iran as a small-scale harvesting method. Mule logging in Namkhaneh district of Kheyrud Forest within this ecoregion was studied to develop hauling regression models and estimate haulage costs. A continuous time study was conducted of hauling of sawn-lumber, pulpwood and fuelwood, to assess mule logging productivity and cost for sawn-lumber and pulpwood as well as fuelwood hauling. Hauling distance was found to be the most important cost factor in wood extraction by mule. The hourly production rates of hauling with mule were 0.84, 0.52 and 0.42 m3 for sawn-lumber, pulpwood and fuelwood, respectively. The cost of the mule hauling system USD 13 per productive mule hours. Hourly costs of mule hauling of sawn-lumber, pulpwood and fuelwood logging were 15.5, 25, and 30.6 USD/m3. Increasing hauling distances caused a linear increase in haulage cost. There appears to be an opportunity to reduce cost of log production by increasing scheduled work hours, wider utilization of mules and reducing labour cost. 相似文献
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Chao Li Shongming Huang Hugh Barclay Derek Sidders 《Journal of Sustainable Forestry》2013,32(3):217-233
ABSTRACTAlthough sustainable forest management is accepted worldwide in concept, challenges in the methods of implementation remain. Using local data sets from Alberta, Canada, we show that a simulation approach can assist the implementation of sustainable forest management by improved understanding of product potential and other forest ecosystem goods and services that forests can provide for a given forest inventory. This will assist facilitating trade-offs among them for an optimal wood utilization strategy to achieve sustainable forest management. In this example, effects of wood utilization standard on merchantable volume, lumber volume, and number of trees that can produce at least one piece of lumber are quantified, and a conversion method for wood volumes under different wood utilization standards is presented. Wood utilization standard is the combination of stump height and diameter inside bark at merchantable height, which considerably influences available volume quantity of forest resource. However, such influences have not been quantified for sustainable forest management implementation. Our results not only confirmed that merchantable and lumber volumes increased with decreasing stump height and diameter inside bark at merchantable height, but also revealed that this trend will not hold when diameter inside bark at merchantable height is less than 7 cm. 相似文献
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Vincent P. Medjibe Francis E. PutzMalcolm P. Starkey Auguste A. NdounaHervé R. Memiaghe 《Forest Ecology and Management》2011,262(9):1799-1806
Selective logging is an important socio-economic activity in the Congo Basin but one with associated environmental costs, some of which are avoidable through the use of reduced-impact logging (RIL) practices. With increased global concerns about biodiversity losses and emissions of carbon from forest in the region, more information is needed about the effects of logging on forest structure, composition, and carbon balance. We assessed the consequences of low-intensity RIL on above-ground biomass and tree species richness in a 50 ha area in northwestern Gabon. We assessed logging impacts principally in 10 randomly located 1-ha plots in which all trees ?10 cm dbh were measured, identified to species, marked, and tagged prior to harvesting. After logging, damage to these trees was recorded as being due to felling or skidding (i.e., log yarding) and skid trails were mapped in the entire 50-ha study area. Allometric equations based on tree diameter and wood density were used to transform tree diameter into biomass.Logging was light with only 0.82 trees (8.11 m3) per hectare extracted. For each tree felled, an average of 11 trees ?10 cm dbh suffered crown, bole, or root damage. Skid trails covered 2.8% of the soil surface and skidding logs to the roadside caused damage to an average of 15.6 trees ?10 cm dbh per hectare. No effect of logging was observed on tree species richness and pre-logging above-ground forest biomass (420.4 Mg ha−1) declined by only 8.1% (34.2 Mg ha−1). We conclude from these data that with harvest planning, worker training in RIL techniques, and low logging intensities, substantial carbon stocks and tree species richness were retained in this selectively logged forest in Gabon. 相似文献
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Long-term forest development programs in Germany aim on an increase of close-to-nature broadleaf forest stands. This means that the economic importance of European beech is expected to increase. The economic potential of a tree basically consists of the stem as well as the economically viable wood volume in the crown. Due to the high morphological variability of European beech crowns, taper models are often not satisfactory for predicting the economically viable wood volume arising from crowns. Prediction models with a higher precision are recently still lacking. Aim of this study is thus the development of prediction model for the economically viable crown wood volume of European beech trees.We determined the distribution of the wood volume in the crown over the branch diameters using the multistage ‘randomized branch sampling’ method (RBS). The tree-specific wood volume distribution on the branch diameters were used to cluster all sampled trees into 3 groups. Additionally, we developed a method able to distinguish between economically viable and unviable crown branches. Basing on the RBS measurements as well as revenues and processing costs, we modeled the economically viable wood volume from the crown for each tree. To calculate the wood volume under bark, we parameterized a bark thickness function from disk samples of the trees.We showed that the European beech crowns could be clustered into 3 groups differing in their wood volume distribution. The economically viable wood volume in the crown significantly depended on this grouping parameter as well as diameter at breast height (DBH). By contrast, the total amount of wood in the crown only depended on DBH. The differing viable wood volumes in the crowns were thus explained by different wood distributions and not by differing total crown wood volume. To make the results applicable in practice forestry, the modelling results were used to develop a regression formula able to predict the economically viable wood volume in the crown depending on the DBH and the crown type. As the crown type can also be predicted via measurable tree covariates, the regression model of the viable wood volume in the crown can be used as a support tool for the management of European beech stands. Sensitivity analysis quantifies how harvest revenues and costs translate into different viable tree volume. 相似文献