森林资源资产评估智能决策支持系统的设计

指出了森林资源资产评估是森林资源管理中十分重要的一部分,通过对森林资源资产的评估,可以了解和认识森林资源,加强对森林资源的管理和利用。对森林资源资产评估的各方环节进行了研究,提出了一个适合森林资源资产评估决策支持系统。     

森林资源“一张图”在广西森林资源管理平台中的应用

为了提高森林资源监管水平、实现森林资源精细化管理,活用森林资源管理平台,广西森林资源"一张图"与森林资源管理平台相结合,在森林资源管理、林业专题开发、森林资源监测、森林资源更新等方面发挥了重要作用,有效地解决了资源管理中图属分离、标准不一、更新困难等问题,为森林资源信息化管理提供了新手段。     

柴河林业局森林资源经营管理建议

为掌握森林资源发展动向,文章以柴河林业局2006年森林资源二类调查资料为依据,对柴河林业局的森林资源经营管理成效和森林资源动态变化进行了分析,并根据其森林资源特点对今后的森林资源经营管理工作如何发展提出了建议。     

山西省森林资源现状及保护发展对策

以第八次全国森林资源清查山西省森林资源清查成果(2010)为主要依据,阐述了山西省森林资源的现状与特点以及森林资源发展存在的问题。针对森林资源总量不足、质量不高、宜林地数量相对较多等制约森林资源发展存在的问题进行分析,提出了森林资源保护发展对策。     

辽宁省森林资源档案的管理和更新

文章回顾了国内外森林资源管理现状,介绍了主流的森林资源管理和更新技术手段,从数字林业标准建立、基础数据库建设、森林资源管理系统建设和森林资源数据更新等方面说明辽宁省森林资源数据管理和更新方法,并总结了森林资源管理存在的问题和挑战及未来发展趋势。     

浅谈创新黑茶山林区森林资源管护机制

介绍了黑茶山林区森林资源状况,分析了近年来该林区森林资源保护成效与存在的问题,从森林资源资产化管护、加强森林资源保护及推进森林资源资产化管护等方面提出了相应对策。     

加强监督 依法保护森林资源

国家林业局驻内蒙古自治区森林资源监督专员办事处 ,是国家林业局（原林业部）派出的专司森林资源监督的专业机构。１９８９年成立以来 ,在国家林业局的领导下 ,按照国家林业局授予的职权 ,对内蒙古自治区森林资源管理工作实施监督 ,有效地保护了森林资源。一、积极开展森林资源监督工作（一）加强了森林资源监督机构建设。１９８９年林业部驻内蒙古自治区森林资源监督专员办事处成立以来 ,内蒙古大兴安岭林管局向所属１９个林业局派出了森林资源监督专员办事处 ,各林业局向所属林场派出了森林资源监督站１３１个 ,形成了监督网络。现在共有…     

乌尔旗汉林业局森林资源资产价值评估探析

森林资源资产价值评估伴随着我国林业体制改革而产生并发展,已经成为实行森林资源资产化管理的一项重要工作。文中介绍了乌尔旗汉林业局森林资源概况,研究确定了森林资源价值评估方法,对乌尔旗汉林业局森林资源资产价值进行了评估,提出森林资源资产增值建议。     

紫金县森林资源保护管理浅议

分析了紫金县森林资源的现状,指出了紫金县森林资源管理中存在的问题：森林资源结构欠合理、森林生态功能脆弱、破坏森林资源行为时有发生、群众保护森林资源意识有待提高等。提出了加强森林资源保护管理的6项措施：加强森林资源的监督管理、加大森林资源保护管理宣传教育力度、大力开展植树造林、规范林地管理、落实森林防火责任制、加强森林病虫害防治等。     

对森林资源资产评估的探讨

根据森林的特性,阐述了森林资源资产评估的复杂性和艰巨性,提出了森林资源资产界定的方法及森林资源资产评估的方法。对进行森林资源资产评估、实现森林资源资产的合理流转具有指导意义。     

Collembola in low stumps at clear-cuts. Is stump harvesting a threat?

Abstract

Stump harvesting as a way to increase wood biomass production in order to meet the European Union targets for reduced CO₂ emissions is starting up in Sweden. The knowledge about if and how Collembola species can use low stumps as a substrate is very limited. Stumps of three different ages (4, 14 and 75 years) were sampled to see if Collembola used the dead wood during the whole rotation period of a forest. Stumps of spruce, pine and birch were compared. Both the bark and the splint wood of the stumps were sampled. To determine whether the stump also influenced the nearby soil, the soil close to the stump were sampled as well as the soil further away. In total, five Collembola species that are known to prefer dead wood as a substrate were found in the stumps. Wood specialists were more dominating in young stumps, but occurred also in the oldest stumps. No preference was found for any specific tree species. Wood-living Collembola seem to be able to survive in low stumps for a whole rotation period, at least in low numbers. There is, however, a risk for extinction debt due to their low capacity for active long-distance dispersal.     

Spatial integration in the Nordic timber market: Long‐run equilibria and short‐run dynamics

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.     

石棉县的大凉螈分布、种群现状及保护建议

大凉螈是大凉山地区的特有两栖动物,具有重要的进化地位和保护关注度,石棉县是该物种重要的分布区之一。本文通过实地调查和问询法,调查了大凉螈在石棉县的分布及种群现状。发现该物种在石棉县分布较广,目前调查到有8个分布点,其种群数量较丰富,栖息地类型选择宽泛;但该种群受人为捕捉、环境污染、外来物种入侵和繁殖场地减少等影响,部分种群有下降趋势。根据研究结果提出了一系列的针对性保护措施和建议。     

A multiple fracture test for strain to failure distribution in wood

The tensile strain to failure of small wood samples is a desirable property in studies where the effect of small differences in microstructure on failure is of interest. However, the scatter in data is usually significant and only one data is obtained per specimen. For this reason, a new multiple fracture test for measurement of the strain to failure distribution was designed. Wood samples were bonded between two transparent PVC layers with higher strain to failure than the wood. Multiple fractures were then observed in single wood samples during tensile loading. This behavior is already utilized in tests in the field of synthetic composite materials. It was possible to conveniently register multiple fracture events as a function of strain by visual observation through the transparent PVC layers. The data were used to compare two different wood materials and to determine their Weibull distribution functions.Financial support from SJFR is gratefully acknowledged     

茶树品种槠叶齐树冠结构动态变化的数学模型探讨

本研究选用湖南省规范化载培茶园１～１８年生的槠叶齐品种为材料,以与产量、品质密切相关的１４项树冠结构指标的动态变化规律。测定结果表明,树冠结构指标与树龄均可建立相应的数学模型,这为槠叶齐品种在规范化载培条件下树冠结构达到测定提供了科学依据。     

隐球壳属(Cryptosphaeria)引起的杨树溃疡病

Cryptosphaeria在欧、美是一类重要病原菌,在我国亦有报道,不仅能引起杨树病害,而且还能引起杨木的腐朽和变色,对杨树的生长潜在着很大的威胁。作者评述了该病的研究历史、分布、危害和发病规律等。     

Chemical changes of kenaf core binderless boards during hot pressing (I): influence of the pressing temperature condition

Self-bonding is the main factor of the performance expression of binderless boards, and therefore its clarification is considered to be an important issue. For this purpose, a series of chemical analyses were conducted on kenaf core binderless boards and their chemical changes during the hot-pressing process are discussed in this article. First of all, binderless boards were prepared from kenaf core powder at different pressing temperatures (without steam-explosion process) and were used for chemical analyses after they were reduced into powders and extracted with methanol. To investigate their chemical changes, lignin, holocellulose, and neutral sugar contents were determined, Fourier transform infrared (FTIR) spectra were recorded, and the nitrobenzene oxidation procedure was applied. As a result, it was found that parts of lignin and hemicelullose were decomposed during the hot-pressing process; however, the contribution of the resulting fractions to selfbonding was not observed. In addition, progress of condensation reactions in lignin and the formation of chemical bonds by low molecular weight conjugated carbonyl compounds in methanol extractives were observed. Thermal softening of lignin is also suggested to play an important role in the expression of board performance.     

Fatigue in wood-based panels. Part 2: property changes during fatigue cycling of OSB, chipboard and MDF

Wood-based panels are viscoelastic so when a load (stress) is applied to them there is a time lag before a deflection (strain) is produced, which results in hysteresis (a loss of energy). The capture of stress versus strain hysteresis loops is a non-interruptive method of monitoring the damage produced during fatigue testing. Hysteresis loops were captured throughout the flexural fatigue testing of OSB, chipboard and MDF in four-point bending allowing the development of fatigue damage to be followed. The MDF tested had a greater mean bending strength than the OSB and chipboard. When stresses were applied to the materials as a percentage of their bending strengths, the stresses applied to the MDF samples were larger than those applied to the OSB and chipboard samples. As a result the microstrains were greater for MDF than for the chipboard and OSB. The OSB was stiffer than the chipboard and MDF, which were both of similar stiffness. The information gained from the hysteresis loops indicates that the OSB, chipboard and MDF all had fatigue limits just below 20% of their bending strengths. The fatigue limit for the MDF is likely to be slightly lower than for the chipboard and the OSB.     

外来入侵种飞机草在广东的分布与危害

文章在全面介绍外来入侵种——飞机草(Eupatorium odoratum)生物生态学特性的基础上，调查分析了飞机草在广东的分布与危害。结果发现，飞机草在湛江、茂名、阳江、江门、广州等地均有分布，其中徐闻、雷州受害严重。还对飞机草的防治作了初步介绍。     

A selection experiment for height growth with cuttings of Picea abies (L.) Karst

Twenty sets, each consisting of a tall, a medium, and a small plant, were selected from a 2 by 2‐year‐old nursery crop. Selection differential was measured. Cutting propagation was undertaken and the subsequent clones were tested in a field experiment. Differences between groups at age 1, 2, 3, 6, 8, and 10 were calculated, and ortet/ramet regressions and age‐to‐age correlations were conducted. Selection of the tall plants gave a response of approximately 17% at age 10. Accumulated genetic gain at this age by a specified stepwise selection procedure is estimated to 36%. Step one is the early selection in the nursery, step two is a later selection amongst the early selected clones and performed after 7 years’ field testing. Ageing of clones, selection for other traits and application of the clones over a variety of sites will reduce these gains.