抚育间伐对森林生长的影响及其模型研究

抚育间伐对森林生长的影响体现在很多方面,包括对林分生产力及其林分因子、林下植被及灌木、林下土壤和天然更新影响等方面。对国内外学者在这些方面的研究进行了综述,简单介绍了抚育间伐对森林生长影响的模型研究进展情况。指出了抚育间伐对森林生长影响研究方面存在的问题及今后的发展趋势。     

抽样估计在森林间伐设计控制木材采伐限额中的应用

应用简单随机抽样估测法和分层抽估测法来达到间伐抚育的目的和执行木材的限额采伐。     

森林培育过程中的森林抚育间伐措施探讨

指出了森林培育工作作为植树造林工程的重要组成部分,对我国林业的稳定发展起到了重要作用,提高森林培育工作的效率,不仅能够进一步增加森林植被的覆盖率,还能够提升森林树木的经济价值。森林抚育间伐措施就是森林培育工作中重要的科学培育手段,通过抚育间伐能够使森林结构更加合理。基于此,针对森林培育中的抚育间伐措施进行了探讨,分析了存在的问题,提出了对策与建议,以期提供参考。     

浅谈中幼林抚育间伐

抚育间伐的主要目地是调整林分组成,提高森林质量和单位面积产量,改善林分卫生状况,增强和发挥森林多种效能。目前将中幼林的抚育间伐分为透光抚育(透光伐)和生长抚育(生长伐)。     

抚育间伐对森林生物多样性影响研究进展

森林生物多样性在一定程度上是衡量森林质量的重要指标, 丰富的生物多样性同时也是生态系统稳定的基础, 会促进生态系统功能的优化, 而抚育间伐与森林生物多样性存在密切的关系。文中针对国内外森林抚育间伐对植物、动物和微生物多样性影响的研究进行了综述, 同时针对我国森林尤其是人工林质量低的现状, 提出3点建议:(1)把生物多样性作为评价森林质量的一项重要指标; (2)把抚育间伐作为提高生物多样性和森林质量的一项重要措施; (3)对森林抚育对生物多样性的影响进行长期定位研究。     

天然次生林抚育间伐试验研究

天然次生林抚育间伐试验研究罗文杰（宝鸡市林业工作中心站）康灵山（宝鸡市林业局）王中民（凤县黄牛铺林场）为了摸清次生林抚育间伐的强度、间隔期、选木等主要技术因子及在不同林分状况下的反应，探索间伐作业的生物及经济效果，验证宝鸡地区产生的次生林密度管理表，...     

人工大叶桉林抚育间伐试验

大叶桉 (Ｅｕｃａｌｙｐｔｕｓｒｏｂｕｓｔａ)树干通直 ,材质重 ,耐腐 ,可作矿柱、枕木、建筑材等用。它适应性强 ,自引种到我国 ,现已集中成片造林。其栽培管理技术方面的研究报道已较多 ,但抚育间伐技术在国内还少有报道。笔者于 1991年 1月对禄丰县一平浪煤矿矿区人工大叶桉林进行抚育间伐作业设计 ,同时设置永久标准地 ,定位调查。1988～ 1989年间营造的大叶桉林到 1991年已表现出明显的分化 ,由于林分密度较大 ,致使林木生长受到严重影响 ,加之矿区木材短缺 ,若适时开展抚育间伐既可改善林内矛盾又可提供部分薪材。1　材料与方法1 1…     

白桦次生林抚育间伐林分生长效果的探讨

我们于1963年在亚布力林业局虎峰施业区进行了白桦次生林的抚育间伐试验。经过20多年来的观测,现将有关生长效果简介如下。一、试验地基本情况试验地位于尚志县东端,张广才岭西坡,虎峰施业区的26林班,北纬44°59′～45°53″,东经128°53″～129°之间。地势平坦,肥土层较厚。年降水量900毫米,早霜期为9月下旬,晚霜期为5月下旬,无霜期在120天主右。年有效积温为1808℃,最高温度35℃,最低温变一38℃左右,年平均温度     

抚育间伐对森林生态系统水文生态功能的影响

抚育间伐为促进林木生长创造良好的营养空间和环境条件,是实现森林生态系统可持续经营的关键性措施。通过改变森林生态系统树种组成、空间分布、层次结构,进而对森林生态系统主要水文生态过程产生影响。该文综述了抚育间伐对森林生态系统主要生态过程水文生态功能的影响,为实现新时代条件下森林生态系统的可持续经营提供理论参考。     

谈抚育间伐的目的和方法

文中对抚育间伐的目的进行了分析，并从有利于森林培育出发，提出了在抚育间伐作业中应执行的几点原则。     

抚育间伐对林分结构及群落演替的影响

通过对同龄单层林、同龄复层林、异龄复层林的抚育间伐试验，调整了林分结构，改善树处组成、加快群落的演替，达到集约经营的目的。     

Efficiently mapping an appropriate thinning schedule for optimum carbon sequestration: An application of multi-segment goal programming

Thinning is an important strategy for carbon sequestration in forest management. Linear programming (LP) and goal programming (GP) can only set fixed parameters for the left hand side constraints, which are incapable of simulating different thinning intensities at thinned stands to map an appropriate thinning schedule for optimum carbon sequestration efficiently. However, multi-segment goal programming (MSGP) with the flexibility to set multi-level parameters can be applied by forest managers to quickly choose an appropriate level from different thinning intensities.The purpose of this study was to combine MSGP with LP to efficiently adopt thinned area and thinning intensity together as decision variables. In a demonstrated case, an appropriate thinning schedule for three age-classes was chosen from 768 combinations of thinning intensity in just one step. Each age-class was allocated well such as practicing medium thinning intensity on young age-class and strong thinning intensity on the old age-class. Totally 1379643.03 tons of carbon sequestration was obtained after two planning horizons, which was 34.75% higher than no thinning. Besides, a stable supply of wood form thinning is made for carbon sequestration in each period and the stocking of each age-class is also improved.     

Effect of thinning on LAI variance in heterogeneous forests

Leaf Area Index (LAI) is a main variable controlling carbon and water fluxes. This paper estimated the effect of thinning on the spatial distribution of leaf area in French forests. While many studies have focused on average LAI, we estimated clumping and measured both average LAI and the variation around it. LAI was derived from digital hemispherical photos at three sites: an unmanaged Fagus sylvatica forest in temperate area (control site), a mixed Mediterranean forest of Quercus ilex and Pinus halepensis, and regeneration of F. sylvatica under a mature stand of Pinus nigra in mountainous area. LAI measurements were also made with LAI 2000 devices over 5 years (from 1994 to 1998) within forest stands dominated by either beech (F. sylvatica L.), by oaks (Quercus petraea (Matus) Liebl., Quercus robur (Matus) Liebl.), or by Scots Pine (Pinus sylvestris L.). Thinning led to a variable decrease in LAI. The coefficient of variation of LAI (CV_LAI) provided a useful ecological index of the level and type of thinning. For undisturbed stands, CV_LAI varied from 10% to 20%, corresponding to the higher average LAI values. Disturbances created by thinning increase LAI spatial variability, resulting in larger CV_LAI values for all stands considered. Possible explanations of these results and use in remote sensing were discussed.     

对双鸭山林区森林分类经营的认识

本文对双鸭山林区森林的分类经营提出了几点认识,并做了具体分析。     

Thinning inventory technique and its application in forest resource inventory

IntroductionForestpIanningrequiresinformationabouttheCurrentstateoftheforestresource.Themostcom-monstock-takingactivitiesarestandbasedinvento-riesscubascompartmentsamplingandsystematicsampIingschemesforforeststratainvoIvingpIots.ThesecIassicaIstock-takingactivitiesarescheduIedtotakepIaceatperiodictimeintervaIs.WiththeabandonmentofcIearfelIing,standstructureandcomplexitiesinthevariablesusedtodescribeforeststatushaveaccordinglyincurredchanges,sonewfactorsandtechniquesmustbeintroducedandadde…     

谈森林的二种生态效益

本详细论述了森林在保护生态环境、防灾、防雪方面的作用,从而提出只有加大森林面积,才能更好的发挥森林的生态效益。     

Effects on stem growth of Scots pine 33 years after thinning and/or fertilization in northern Sweden

Thinning and fertilization are two common and important stand treatments in forest management. In terms of area treated, thinning is the single most common form of stand treatment. The extent of forest fertilization on the other hand, has varied widely in recent decades and is currently not very common. Thinning is done primarily to promote stand properties while fertilization is done to increase growth before future final felling. After thinning stands of Scots pine, overall growth decreases, while growth of residual trees increases. An experiment was established outside Vindeln in northern Sweden where the long-term growth effects after thinning and/or fertilization were evaluated after 33 years. Experimental set-up was a randomized block design including 12 replications of four treatments. Treatments were control, fertilization, thinning, and thinning and fertilization combined. Thinning decreased overall and annual volume growth ha^?1, and increased green crown size and diameter growth at breast height (1.3 m, DBH) for the individual trees. No positive growth responses to fertilization could be seen after 33 years. In summary, this study showed that thinning can have long term effects on the growth of a Scots pine stand in northern Sweden. Possible reasons for the lack of positive response following fertilization are discussed.     

Biodiversity response to intensive biomass production from forest thinning in North American forests - A meta-analysis

Demand for alternative energy sources has led to increased interest in intensive biomass production. When applied across a broad spatial extent, intensive biomass production in forests, which support a large proportion of biodiversity, may alter species composition, nutrient cycling and subsequently biodiversity. Because forest thinning and fuels treatment thinning are viewed as possible wide-spread biomass harvest options, it is important to understand what is known about forest biodiversity response to these practices and what additional information is needed by forest managers and policymakers. Therefore, we summarized documented relationships between forest thinning treatments and forest biodiversity from 505 biodiversity effect sizes (incl. taxa and guild abundance and species richness measures) from 33 studies conducted across North America. We used meta-analysis to summarize biodiversity response by region, taxa and harvest treatments. Biodiversity responses included species richness, diversity, abundance of taxa or groups of species (guilds) and abundance of individual species for birds, mammals, reptiles, amphibians, and invertebrates. Forest thinning treatments had generally positive or neutral effects on diversity and abundance across all taxa, although thinning intensity and the type of thinning conducted may at least partially drive the magnitude of response. Our review highlights the need for more research to determine effects of thinning on amphibians and reptiles and manipulative experiments designed to test the effects of biomass removal on biodiversity.