伐区核查采伐量与小班资源消耗量分析

利用某县66个可对比的伐区核查采伐量和小班资源消耗量资料进行对比分析，表明单一伐区核查采伐量比较准确，但总体结果比伐区实际采伐量小，小班资源消耗量误差大，但样本多的情况下其总体数量可作为伐区实际采伐量的总体结果的参考依据。     

类型中心抽样在林木采伐管理检查伐区抽查中的应用探讨

本文利用类型中心抽样对林木采伐管理检查伐区抽查方案进行了设计，并应用中心抽样理论对评价林木采伐限额管理的主要指标（伐区凭证采伐率、发证采伐量误差率）进行了实例分析，从理论上科学地解决了对受检总体检查结果出数问题，从而可以用数据对受检总体的林木采伐管理作出评价。     

天然林保护工程下的森林采伐伐区管理

在进行木材生产过程中，怎样才能实施好天然林保护工程，抓住伐区管理这个木材生产的源头，是关键的关键，本文详细的阐述了从伐区拨交到验收全过程的管理方法及要求，为加大天然林保护的力度起到了重要作用。     

关于伐区小班采伐量核查估计精度及影响因素的分析

文章就伐区小班采伐量核查,探讨小班采伐量的影响因素作了分析,说明了小班采伐量核查的重要性。     

利用地理信息系统进行伐区采伐作业调查设计

为实现资源数据与图面资料的系统管理,利用森林资源管理与监测地理信息系统,经过一定的组织和定期的统一更改,实现数据和林相图的更新以及在此基础上的伐区调查设计工作.伐区设计、伐区生产管理与地理信息系统及GPS定位相结合,实现图形库与档案库的互查互动,全面掌握伐区情况.伐区设计的图文材料一次完成,形成从采伐许可、组织伐区作业到伐区验收一整套严格的采伐作业管理程序.     

绥宁县林木采伐伐区调查设计工作探讨

通过总结和分析绥宁县林木采伐伐区调查设计工作,充分认识到保护和合理采伐利用森林资源的重要性,认为做为林木采伐伐区调查设计工作者要熟练掌握伐区调查设计技术规程、具体内容,用法律法规政策约束自身行为,正确处理伐区调查的各种关系,加强林木采伐伐区质量管理,切实提高伐区调查设计精度,达到合理采伐利用森林资源的目的。     

伐区调查设计对森林采伐量的影响

研究分析伐区调查设计对森林采伐量的影响,主要有三个方面：①伐区调查设计过程对森林采伐量精度的影响,树木胸高确认不同,森林采伐量误差值越大;调查人员测量胸径时所站位置不同,其森林采伐量也不一样;立木所处地形及不同测量工具和调查设计人员,其测量结果都有影响;②枯立木、风倒木对森林采伐量精度的影响;③伐区调查设计规程对森林采伐量精度的影响。总结目前伐区调查设计中存在的问题,寻找提高采伐量精度的方法,为今后伐区的合理的调查设计以及采伐作业提供理论依据。     

浅谈地理信息系统技术在伐区采伐作业调查设计中的应用

利用森林资源管理与监测地理信息系统,实现伐区设计、伐区生产管理与地理信息系统及GPS定位相结合,实现图形库与档案库的互查联动,全面掌握伐区情况。伐区设计的图文材料一次同时完成,形成从采伐许可、组织伐区作业到伐区验收一整套严格的采伐作业管理程序。     

双重分层抽样技术在森林采伐限额检查中的应用

随着环境问题的不断严重,可持续发展观点的不断增强,国家、社会、人民对森林资源的利用有了更细致的关注,为了保证森林资源总量的持续增长,森林限额采伐检查工作逐步受到了重视.以森林采伐限额检查中抽样检查技术为主要研究内容,结合抽样技术现状,总结出了抽样技术存在的问题,并提出综合性的抽样技术方法,以保证最大限度地提高检查的可靠性和精度,同时尽可能减少检查的工作量.     

Mathematical modeling for evaluating gain of logging companies in the timber market

We propose a game-theoretic model for a first-price sealed-bid auction (FPSB auction) of standing timber. A FPSB auction means that bidders simultaneously submit sealed bids so that no bidder knows the bid of any other participant. The highest bidder pays the submitted price. The mathematical model has been elaborated considering only two bidders. Each bidder is supposed to know only the probability distribution of the bid of the other bidder. Using appropriate distributions, the adversity and propensity of a bidder to risk can be described. From the view point of a bidder, the conservative solution is calculated for both types of the other bidder. If a standing timber belongs to a public owner, the market has to follow a public evidence procedure, including public auctions. The function obtained is illustrated with a numerical example of a typical standing timber auction from a forest located in central Italy. Considering average costs and prices of the local chestnut timber market, winning bids and expected gains are estimated. Their amounts are comparable with the currently average stumpage price registered in this market.     

Three-dimensional inversion of knot defects recognition in timber cutting

The comprehensive utilization of wood is the main goal of log cutting,but knot defects increase the difficulty of rationally optimizing cutting.Due to the lack of real shape data of knot defects in logs,it is difficult for detection methods to establish a correlation between signal and defect morphology.An image-processing method is proposed for knot inversion based on distance regularized level set segmentation(DRLSE) and spatial vertex clustering,and with the inversion of the defects existing ...     

人工用材林弥补天然林限伐"缺口"可能性分析

我国实施天然林保护,大规模调减木材产量成为必然.根据第四次资源调查的结果,对人工林产材能力进行了详细的测算,结论是我国人工林产材是在一定时期内不能弥补市场"缺口",增加木材进口是必然的.     

福建省国有林场采运工艺与技术探讨

文章对国有林场采集作业方式、装车和运材方式、工艺技术方案的选择进行了较深入的探讨。     

森林采伐限额与林业企业生产经营最优模型

简述实施森林采伐限额对林业企业经济的影响,提出了适合林业企业生产的投入产出与线性规划复合模型,并利用该模型对林业企业生产经营进行优化设计,提出了解决林业企业经济发展与限量采伐矛盾的方法和途径。     

阜新地区杨树用材林栽培品种综合评价

杨树是阜新地区主要造林树种，针对阜新地区栽种的现有杨树品种生长适应性进行了调查分析，并对杨树生长主要因子与本身的生物特性的关系进行评价。37个杨树品系生长适应性差异显，乡土树种小美旱、彰武小钻杨表现为最佳，生产中应大力推广，其他表现较好的树种应继续观察。该对阜新地区杨树的发展提出了具体建议。     

Initial impact of supervised logging and pre-logging climber cutting compared with conventional logging in a dipterocarp rainforest in Sabah,Malaysia

Pre-marked skid trails, directional felling and climber cutting when logging in tropical rainforests may be important ways of reducing damage to the forest, thus creating a healthier stand and improving future yields.This study, carried out in a virgin dipterocarp rainforest in the south of Sabah, Malaysia, compared two types of logging (both with and without pre-cutting climbers): conventional selective logging (CL) and supervised logging (SL). The latter is a selective logging system in which both pre-marked skid trails and directional felling were implemented. The pre-marked skid trails were aligned parallel to each other, spaced 62 m apart. A randomised complete block 2 × 2 factorial design was used in the experiment, consisting of 16 gross treatment plots, each of 5.76 ha with a 1 ha net plot in the centre.Fewer trees tended (0.050 < P ≤ 0.100) to be logged in SL plots than in CL plots (on average 9.4 and 13.0 trees ≥60 cm diameter breast height ha⁻¹). Pre-felling of climbers resulted in four more dipterocarp trees being logged ha⁻¹, compared with no climber cutting: a statistically significant difference (P ≤ 0.050). The basal areas lost of both large trees (≥ 60 cm dbh) and small dipterocarp trees (10–29 cm dbh) tended to differ between the logging systems, with CL leading to greater losses.There were significant differences in the residual stands left by the logging systems, with respect to the number of dipterocarps and their basal area in the diameter class 10–29 cm; ca 30% more stems being found after SL. No significant differences (or tendencies) in these variables were found in the residual stands in other diameter classes, or when trees of all species were considered.     

The role of timber tree species in the nutritional ecology of spider monkeys in a certified logging concession,Bolivia

Selective harvesting of timber can lead to population declines in some primate species. As frugivorous primates are important seed dispersers in tropical forests, the reduction of their populations may affect the ecological sustainability of selectively logged forests. This paper is the first to quantify the importance of timber tree species in the diet and nutritional ecology of a primate species. We studied spider monkeys (Ateles chamek) inhabiting a certified forestry concession in Bolivia where post-logging population declines of this species have been recorded. We show that spider monkeys occupying unlogged areas obtained approximately 50% of their total intake of macro-nutrients from timber tree species and exhibited a distinct preference for foraging within trees that were of harvestable size. Timber tree species dominated the spider monkeys’ diet both during peak fruiting periods and during periods of fruit scarcity. We estimate that under current timber extraction intensities spider monkeys lose significant proportions of their food sources. Our results indicate that further extraction limits could be considered for Ficus boliviana, Spondias mombin and Pouteria nemorosa. We suggest that to ensure long-term ecological sustainability of certified forestry concessions, the importance of timber tree species in the ecology of seed dispersers needs to be taken into account.     

Relationship between near-infrared (NIR) spectra and the geographical provenance of timber

Since trees record all the environmental factors in the wood, many wood properties are related to the site characteristics. Despite of this fact, identifying the origin of a timber has always been considered a difficult task, and no effective tools are presently available for this purpose. The goal of this study was to verify whether significant differences among groups of the same wood species due to the provenance can be detected with Fourier transform near-infra-red spectroscopy (FT-NIR). Spruce (Picea abies L. Karst.) samples collected from stands in Finland, Northern and Southern Poland and Italy were analyzed using two different approaches: for the first approach samples were collected from four provenances scattered in a wide area throughout Europe, while for the second approach the samples were collected from provenances located in a narrow area within the same region in Italy. For the first approach, all the specimens were clearly divided into groups by using statistical methods. The separation among groups from the narrow local area was actual; even though less significant than in the previous case. It was concluded that trees growing in various locations have somewhat different chemical composition, and FT-NIR is sensitive enough to detect such differences. The presented method could be used for tracking wood provenances and as a technical tool for detecting logs harvested illegally from protected areas.     

美登蓝莓的嫩枝扦插繁育技术

美登作为蓝莓的矮丛栽培品种,适宜在吉林东部高寒山区栽培。本文从扦插育苗前准备工作、扦插作业、扦插后的日常管理、上营养钵等方面介绍了在高寒山区美登的嫩枝扦插繁育技术。