共查询到20条相似文献，搜索用时 281 毫秒
1.
红椎大径材近自然培育适用性分析 总被引：3，自引：0，他引：3
根据近自然林经营理念及原则,结合红椎生物、生态学特性及木材利用特性,系统地分析了红椎采取近自然林经营技术培育大径材的适用性。分析认为,红椎为南亚热带地带性常绿阔叶林顶极群落的主要建群种,可以采取近自然林目标树单株培育技术,高效培育大径材多功能人工林。 相似文献
2.
红松是我国重要的珍贵用材树种,为了培育优质高效健康的红松人工林,利用多年调查数据和资料,结合辽宁省森林经营分区和立地条件特点,该文从培育目标、立地条件选择、质量要求、森林作业法等方面,提出红松-阔叶异龄复层林、红松大径材培育兼顾林下经济复合经营培育,以及红松果材兼用林培育的经营模式,为区域红松人工林经营提供技术参考。 相似文献
3.
指出了桉树是我国纸浆材的主要树种,培育出大径材的桉树可以有效地缓解我国对木材的需求,尤其是缓解我国中径木材、大径木材紧缺的失常状况,从而解决我国木材市场上供需不平衡的矛盾.阐述了桉树大径材培育的重要意义,进一步提出了桉树大径材和无节材培育技术的有效策略,以为我国实现桉树种植效益最大化起到参考作用. 相似文献
4.
广西是中国重要的商品林生产基地和木材战略储备基地。每年木材采伐量占全同的36％，但绝大部分是小径材，中大径材很少，胸径30厘米以上的大径材更少。除试验林外，广西造林单位培育大径林商品林的意识还不强。 相似文献
5.
红松属果材兼用树种,具有很高的生态效益、社会效益和经济效益。随着红松种子、红松木材的价值和市场需求不断攀升,辽东地区广大林农营造红松果材林的积极性空前高涨,但是在红松果材林培育和管理过程中,存在着许多的误区和问题,影响了红松果材兼用林的建设和发展,就解决这些问题提几点建议和对策。 相似文献
6.
辽东山区红松人工林不同密度管理培育大径材效果分析 总被引：2，自引：0，他引：2
以辽宁省森林经营研究所68年生的红松人工林为研究对象,分析不同密度管理(间伐)对林分生长及大径材出材量的影响。结果表明:间伐调整密度能有效促进红松人工林平均胸径、树高、单株材积的生长,缩短大径木的培育年限。但间伐强度过大林分株数减少,降低了林分活立木总蓄积量及大径材出材量,中度间伐红松人工林的大径材出材量最大(243.79 m3·hm-2),其次是强度间伐和弱度间伐,但均高于对照。综合考虑,红松人工林大径材培育以中度间伐效果最佳,68年生适宜保留密度为310株·hm-2。 相似文献
7.
随着我国经济建设持续快速发展，木材刚性需求不断增加，木材安全问题受到广泛关注。基于历次全国森林资源清查结果，对我国用材林资源的权属、起源、龄组、树种等基本情况及分布特点和发展趋势进行了阐述，对我国近70年的木材产量、目前的木材需求及木材安全进行了分析。从建设国家储备林基地、大力培育珍贵用材和大径材、加强森林科学经营、提倡木材节约代用、引导规范木材进口等5个方面，提出了保障木材安全的建议。 相似文献
8.
文章较为系统地分析了落叶松林经营中存在的问题,同时有针对性地提出了相应对策。制定不同培育目标的培育技术体系,规范经营标准;中龄林改成培育大径材林的可按目标树作业法作业,近熟林本着伐劣留优的标准,保留300~350株·hm-2进行择伐,伐后进行林冠下人工更新红松、云杉、冷杉等针叶树种,见缝插针造林,以迅速恢复森林环境。 相似文献
9.
10.
11.
Ge Jianping 《林业研究》1994,5(4):1-5
The thesis for the Doctorate consist of two parts. The first is to study on structure, dynamics and tree growth of natural
Korean pine forest. The second is to research for tree architecture, growth and stand structure of artificial Korean pine
(Pinus koraiensis) forests.The thesis compares the stand structure, process of regeneration, and various tree growth patterns between natural
forests and artificial forests. Its purpose is to give a basis for forest management and silviculture. The study was carried
out in Liangshui Experimental Forest Farm, which is located in the southern Xiaoxing’an Mountains. 相似文献
12.
[目的]分析德国推行近自然森林经营20年来的经营效果,总结德国推行近自然森林经营的经验。[方法]在明晰近自然森林经营原则的基础上,基于两期(间隔期10年)资源清查数据对比,对德国大面积推行近自然森林经营20年的经营效果进行分析。[结果]两期资源清查数据表明,德国采用近自然经营20年后,针叶林如挪威云杉和欧洲赤松的面积显著减少,阔叶林和针阔混交林面积持续增加;阔叶树种蓄积平均增长量约为15 m~3·hm~(-2),针叶树种蓄积平均增长4 m~3·hm~(-2),挪威云杉是唯一蓄积下降的树种,下降了5 m~3·hm~(-2);近自然度等级变化表明,人工林面积在减少,而近自然森林的面积在增加,甚至符合原始林等级的森林面积也在增加。[结论]实现近自然森林经营的目标是一个长期的过程,联邦政府促进和保护森林的政策以及林场主所采用的先进的森林经营技术也是德国森林每公顷蓄积达到336 m~3的重要原因;在近自然森林经营的原则下,德国森林中针阔混交林比例显著增加;将近自然程度不高的人工林经营转化为近自然的森林生态系统是德国森林经营所面临的主要问题。 相似文献
13.
Through studying seven analytic trees from two stands ofPinus koraiensis artificial forests, the results show that the individual variation coefficient of tree heigh, dbh and volume decreases with
age increasing after age of 25. Age of 25 is the age that difference of individual growth is from acute difference to comparatively
stability. The optimum selection age is 25a forPinus koraiensis’s artificial forests according to the analysis of juvenile-mature correlation, and early selection efficiency.
(Responsible Editor: Zhu Hong) 相似文献
14.
In close-to-nature silviculture one strives to derive the advantages of the natural adaptations of tree species to different growth conditions. Evidence of the natural distribution of tree species is obtained through vegetation science (recent ground vegetation, primeval forest relicts), studies of old written sources, and pollen and macrofossil analyses. Here we have analysed macrofossil samples of charcoal kiln sites and the recent ecological conditions in the vicinity of these sites, as well as secondary written sources on forest and land-use history. From charcoal analysis of kiln sites we were looking for spatial patterns of past tree species exploitation, with special regard to regional and local differences in the forest growth conditions and the natural wood supply. Therefore, we selected remote forest areas characterised by a high density of kiln sites and significant differences in the ecological conditions. The sample sites ranged over a landscape profile of 40 km, covering many ecological site types. The anthracological results of 181 post-medieval kiln sites were evaluated, considering two spatial scales: the total 40-km profile and a fine-scale profile of 4 km. Considering the charcoal material analysed as a whole, all of the tree taxa to be expected based on the natural conditions were found. The frequencies of the exploited taxa also reflected a natural situation. Wood of the climax vegetation, Fagus, Abies and Picea, was mainly used and all other taxa were quantitatively unimportant. The results for the individual sites showed considerable differences in taxa composition, from which regular spatial patterns of the past tree species distribution were deduced. These regional and local patterns are explained by natural differences in the ecological conditions in the vicinity of the sample sites. At the same time, new indications of the natural tree species composition of our forests are inferred. A pronounced dependency of charcoal production on the local natural wood supply is discernible. No indications of tree species selection or forest degradation could be found. 相似文献
15.
The conversion of anthropogenic into more natural, self-regenerating forests is one of the major objectives of forestry throughout
Europe. In this study, we present investigations on permanent plots with different silvicultural treatment in NE German pine
stands. Management of old-growth pine stands on acidic and nutrient-poor sandy sites differs in fencing, thinning, and planting
of certain tree species. The investigations were carried out on the community, population, and individual level of the pine
forest ecosystems. Thus, vegetation changes, size and height of tree populations, and height increment of tree individuals
were observed over a time span of 6 years. Special attention was paid to short-lived tree species such as, e.g., Frangula alnus and Sorbus aucuparia, as well as to Fagus sylvatica as one of the most typical forest tree species of Central Europe. Vegetation changes are interpreted as a consequence of
natural regeneration of formerly degraded forest sites, involving an increase in nutrient availability. High browsing pressure
can be considered as a key factor for the inhibition of tree seedlings and growth of saplings. Some Sorbus aucuparia individuals, however, succeeded in growing out of the browsing height also in unfenced stands. Few found specimens of Fagus sylvatica proved that this species is able to establish spontaneously on these relatively dry, acidic sites under continental climate
influence. Such natural regeneration processes, also including spontaneous rejuvenation of trees, can be integrated into silviculture
as passive forest conversion management. An active management like thinning of stands, planting of trees, and fencing can
accelerate forest conversion with regard to height growth and species number of trees. 相似文献
16.
选择长白山针阔比9∶1、8∶2、7∶3的云冷杉过伐混交林,探讨直径结构、空间格局、蓄积生长、林下更新以及植物多样性等林分结构问题,为恢复红松为主的针阔混交林,提出结构调整思路。研究表明:由于过去以不合理的非经营性采伐,红松成主要择伐对象,红松不同年份各径阶株数变化幅度较大,直径18 cm开始出现缺损株数现象,缺乏中、大径组株数,导致母树数量、结实量和种源减少,造成在主要树种中红松更新最差的问题,不利于林分正向演替。不同针阔比混交林空间格局与其主要树种空间格局并非完全一致,在同一林分不同树种间存在差异。针阔比9∶1、8∶2、7∶3的混交林空间格局分别为随机分布、聚集分布和均匀分布。其中,红松分布格局主要呈聚集分布。因此,恢复以红松为主的针阔混交林,以红松和珍贵阔叶树种作为目标树种,采取目标树培育方法,伐除影响其更新和生长的林木,而将云冷杉和一般阔叶树作为伴生树种,逐渐减少云冷杉的优势,最终逐渐恢复成红松阔叶混交林;对针阔比8∶2和7∶3混交林红松分布格局,采取人工补植、间伐等措施,结合天然更新,向随机分布进行调整;采取人工补植、清理母树周围枯枝落叶层等措施人工辅助红松天然更新。 相似文献
17.
Guillermo Martínez Pastur María Vanessa Lencinas Juan Manuel Cellini Pablo Luis Peri Rosina Soler Esteban 《Forest Ecology and Management》2009
Forestry practices integrating ecological and social criteria have been replacing those based only on economic values. Traditional silviculture, such as shelterwood cuts (SC), transforms uneven-aged original stands to an even-aged managed forest. Recently, other methods have proposed to conserve some of the original heterogeneity of the old-growth forests. One proposal leaves 30% of the timber quality forest area as aggregated retention and 20% basal area as dispersed retention. The aim of this study was to analyze the feasibility of timber management with aggregated and dispersed retention in Nothofagus pumilio old-growth forests by analyzing timber and harvesting yield potential compared with traditional regeneration systems. Also, remnant tree stability of aggregated retention was analyzed. 相似文献
18.
Fallen wood decomposition rate ofPinus koraiensis andTilia amurensis in broadleaved Korean pine forest was studied in this paper. The result showed that decomposition rate of fallen wood was
different from that of little diameter wood and coarse woody debris for the same tree species. Fallen wood decomposition was
generally rotten from outside to inside. And decomposition speed of fallen woods was different according to tree species and
site, and it was also related to diameter of fallen woods. Decomposition depth ofTilia amurensis fallen wood for 17 years was 14 cm, but that ofPinus koraiensis in the same condition was less than 7 cm.Tilia amurensis was decomposed faster thanPinus koraiensis. For same tree species, if the diameter was small, the decomposition speed was quick.
This project was supported by Natural Science Foundation of China (No. 39670144) and funded by the Opened Research Station
of Changhai Mountain Forest Ecosystem, Chinese Academy of Sciences.
(Responsible editor: Zhu Hong) 相似文献
19.
20.
Z. Villegas M. Peña-Claros B. Mostacedo A. Alarcón J.C.Licona C. Leaño W. Pariona U. Choque 《Forest Ecology and Management》2009
Silvicultural treatments are often needed in selectively logged tropical forest to enhance the growth rates of many commercial tree species and, consequently, for recovering a larger proportion of the initial volume harvested over the next cutting cycle. The available data in the literature suggest, however, that the effect of silvicultural treatments on tree growth is smaller in dry forests than in humid forest tree species. In this study, we analyze the effect of logging and application of additional silvicultural treatments (liana cutting and girdling of competing trees) on the growth rates of future crop trees (FCTs; i.e., trees of current and potentially commercial timber species with adequate form and apparent growth potential). The study was carried out in a tropical dry forest in Bolivia where a set of 21.25-ha plots were monitored for 4 years post-logging. Plots received one of four treatments that varied in intensity of both logging and silvicultural treatments as follows: normal (reduced-impact) logging; normal logging and low-intensity silviculture; increased logging intensity and high-intensity silviculture; and, unlogged controls. The silvicultural treatments applied to FCTs involved liberation from lianas and overtopping trees. Results showed that rates of FCT stem diameter growth increased with light availability, logging intensity, and intensity of silvicultural treatments, and decrease with liana infestation degree. Growth rate increment was larger in the light and intensive silvicultural treatment (22–27%). Long-lived pioneer species showed the strongest response to intensive silviculture (50% increase) followed by total shade-tolerant species (24%) and partial shade-tolerant species (10%). While reduced-impact logging is often not sufficient to guarantee the sustainability of timber yields, application of silvicultural treatments that substantially enhanced the growth rates of FCTs will help move the management of these forests closer to the goal of sustained yield. 相似文献