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1.
Each link in initial process of artificial regeneration ofPinus koraiensis in clear cutting site was researched. The seedling recovery processes after transplantation, the affecting seedlings survival
factors in different time, and the characters of seedling growth were analyzed. Results of this study suggest that the root
recovery of Korean pine seedlings after transplanting is the key link in the artificial regeneration management. The synthetically
management was proposed on basis of seedling root recovery process.
The project was surpported by Natural Science Fund of Heilongjiang Province 相似文献
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《Forest Ecology and Management》1997,93(3):215-225
The seedling establishment of Juniperus procera Hochst. ex Endl. and Afrocarpus gracilior (Pilger) C. N. Page was assessed in the Afromontane forests of Ethiopia. Percent light transmission, litter depth and percentage cover of vegetation were assessed for seedling microsites in five sites with different levels and history of disturbance. The response of natural and artificial regeneration to burning, mechanical scarification (removal of all logging waste and ground vegetation) and cultivation following clear felling and timber extraction was assessed 19 months after treatment.There was no evidence that regeneration was correlated with light intensity. Despite the presence of a viable seed bank in the undisturbed forest floor, removal of the overstorey vegetation by clear felling did not encourage natural regeneration of J. procera. This suggests that light may not be the main factor limiting regeneration of J. procera.Natural regeneration of J. procera can withstand exposure and is compatible with management by ‘clear cutting with seeding from adjacent stands’ together with ground treatment, particularly controlled burning which exposes the minearl soil and releases nutrients. In contrast, both clear felling and surface disturbance will discourage the natural (or artificial) regeneration of A. gracilior suggesting that J. procera is a pioneer species which is more exposure-tolerant, whilst A. gracilior is more shade-tolerant and exposure-intolerant. 相似文献
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本文提出了培育森林后备资源的指导思想要实现６个转变：（１）森林更新方式由营造成片人工纯林为主向“人天混”上转变，（２）森林培育方式由粗放经营向集约经营上转变；（３）森林培育重点由人工造林向抚育天然幼壮林上转变；（４）种苗工作由常规技术向生物遗传工程技术上转变；（５）经营机制由单一全民造林向多元化造林上转变；（６）营林机构单一职能部门向公司化转变。这些举措对森林经营和营林体制改革都具有现实意义。 相似文献
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选择林相较好的12年生天然次生阔叶林，通过择伐更新和皆伐人促更新两种经营方式定向培育食用菌原料林。结果表明：择伐经营的经济效益较高，且有利于群落的快速恢复，经过7a的封育，林分蓄积量已达到择伐前当年的水平。皆伐人促更新获得的食用菌材虽较择伐利用高出40％左右，但因经营强度过大，保留的幼树受损严重而不利于伐后林木的生长与恢复，封育期内蓄积增长量分别为择伐更新和对照未经营区的64．7％和73．4％。动态监测结果显示，采用择伐和皆伐人促更新措施后，群落恢复较快。疏伐后因透光度的急剧增加，阳性和中性树种大量侵入，地面芽植物和1年生植物的比例增高。到第7年时，高位芽植物的比例已接近未经营区的状态，乔、灌、草各层的物种多样性指数高于未经营的天然阔叶林，物种均匀度则与其相近。研究还发现，两种更新经营方式对土壤养分的损失较小，经过7a的恢复，林地土壤肥力已基本达到原有天然林水平。 相似文献
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Post-fire forest regeneration is crucial to forest management. Three different restoration treatments including natural regeneration (NR), artificial regeneration (AR), and artificial promotion (AP), were adopted in the Greater Hinggan Mountain area of China after a serious fire occurred on May 6, 1987. NR is a control treatment where recovery occurs naturally without intervention, AR comprises salvage logging followed by planting, while AP includes regeneration by removing dead trees, weeding, and tidying to promote seed germination. In this study, the objective was to detect and compare the effects of the three restoration treatments using radar indices derived from ALOS/PALSAR data. Four time-series SAR images were pre-processed to acquire the backscattering coefficients. Then the coefficients in both HH and HV polarization were examined and two radar vegetation indices were derived and evaluated, based on which, the post-fire forest dynamics under different restoration treatments were detected and compared. The results showed that the forests under NR presented a completely different recovery trajectory compared to those under the other two treatments. This difference could be characterized by both the backscattering intensity in HH and HV polarization and two radar indices. This study indicated the effects of different restoration treatments, as well as demonstrated the applicability and efficiency of radar remote sensing techniques in forest monitoring and management. 相似文献
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热带雨林濒危树种望天树的致危原因及保护策略 总被引：2，自引：0，他引：2
望天树自身的开花结实特点、种子顽拗性和低成苗率、幼苗生长缓慢、过度砍伐和生境破碎化等导致其更新困难,以致陷入濒危的境地。加强自然保护区管理与法制建设、在天然林保护和次生林恢复工作中辅以人工抚育、防治病虫害和人工接种菌根菌以及实施迁地保护等措施可有效地保护望天树种质资源。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(3):206-217
The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(4):347-357
Abstract The study focused on constructing models for the establishment and seedling height development of naturally regenerated seedling stands in the natural regeneration of Scots pine by the seed-tree method in Lapland, northern Finland. Modelling was used to describe the dynamics of the regeneration process and to analyse the principal ecological factors and management activities influencing regeneration success. Models for the density of seedling stands were developed with the generalized linear mixed model method. The most significant variables affecting seedling establishment were elevation, time since the establishment cutting, the interaction of forest site type and site preparation, and stoniness. The results indicated that the average stocking level tends to remain unsatisfactory on moist, fertile site types without site preparation. Seedling height development was modelled as a function of age using the linear mixed model. Age explained 97% of the variance of seedling height. Other independent variables in the model were effective temperature sum, site preparation and the presence or absence of seed trees. 相似文献
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Rüdiger Otto Eduardo García-del-Rey Pascual Gil Muñoz José María Fernández-Palacios 《European Journal of Forest Research》2010,129(4):499-508
The Canarian pine (Pinus canariensis) exhibits a striking combination of high adult resistance to fire and intermediate serotiny. Hence, the study of its post-fire
regeneration can support valuable new insights about functional adaptations to fire. Here, we analyse the first-year seedling
establishment after fire in a P. canariensis forest on the northern slope of Tenerife, Canary Islands. The effects of fire severity and other explanatory variables on
the seedling density recorded 9 months after fire were examined. We detected a clear unimodal relationship between seedling
density and fire severity, with maximum regeneration associated with intermediate fire severity and no regeneration associated
with very high crown damage. The results suggested that high severity fires may have caused the partial destruction of the
aerial seed bank and/or the creation of unfavourable seedbed conditions for germination and seedling emergence. The density
of large pine trees, reflecting seed availability, was the second most important factor explaining the distribution of seedlings.
Cover of scorched needle litter on the ground correlated strongly and positively with pine seedling density and negatively
with fire severity. The complete lack of regeneration at sites most strongly affected by fire does not represent a major threat
for the stand recovery of the Canarian pine, due to the very high tree resistance to fire and the tremendous capacity of the
Canarian pine to resprout after fire. The observed very high seedling densities at sites with intermediate fire impacts can
probably be related to both the complete liberation of the seed bank (including seeds stored in serotinous cones) and favourable
micro-environmental conditions for seed germination and seedling establishment. 相似文献
11.
The effects of thinning were investigated on naturally regeneratedFraxinus rhynchophylla Hance (Korean ash) grown in the understoreyof a Larix kaempferi (Lamb.) Carr. plantation, established ona site that previously supported old growth hardwood forests.The regeneration characteristics were evaluated after thinningof the plantation (about 60 per cent of relative density wasremoved). In the naturally regenerated and mixed stands, Quercusmongolica Fisch. was the most abundant tree species in the overstorey,but the understorey of the thinned plantations was dominatedby F. rhynchophylla with six other minor tree species. Fraxinusrhynchophylla was regenerated by four propagation types includingnatural seedling, stump sprout, root sprout and layering. Beforethinning, the difference of average height growth for each regenerationtype was insignificant. One year after thinning, the stump sproutsshowed the fastest growth among the regeneration types. Heightgrowth of advance regeneration was slow in the year followingthinning but then increased rapidly surpassing the other regenerationtypes 5 years after thinning. Thinning had an effect on thecomposition of regenerated trees also by seedling, stump sprout,root sprout and layering in the understorey. Advance regenerationsoccupied the upper understorey at 5 years after thinning. Alarge number of stump sprouts emerged in the plots 1 year afterthinning, while at 5 years after thinning the occupation ofstump sprouts decreased. Root sprouts and layers faded away.Considering the early growth and the composition of understoreyF. rhynchophylla, its advance regeneration has a high potentialto develop into overstorey trees at this site. 相似文献
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次生阔叶林改建为食用菌原料林后的群落恢复和林分生长 总被引：6，自引：0，他引：6
选择12年生林相较好的天然次生阔叶林,通过择伐更新和皆伐人促更新2种经营方式定向培育食用菌原料林。研究发现,择伐经营的经济效益较高,且有利于群落的快速恢复,经过7a的封育,林分蓄积量已达到择伐前的水平。皆伐人促更新获得的食用菌材虽较择伐利用高出40%左右,但因经营强度过大,保留的幼树受损严重而不利于伐后林木的生长与恢复,封育期内蓄积增长量分别为择伐更新和对照未经营区的64 7%和73 41%。动态监测结果显示,采用择伐和皆伐人促更新措施后群落恢复较快。疏伐后因透光度的急剧增加,阳性和中性树种大量侵入,地面芽植物和1年生植物的比例增高。到第7a时,高位芽植物的比例已接近未经营区的状态,乔、灌、草各层的物种多样性指数高于未经营的天然阔叶林,物种均匀度则与其相近。研究还发现,2种更新经营方式对土壤养分的损失较小,经过7a的恢复,林地土壤肥力已基本达到原有天然林水平。 相似文献
13.
沿铺面道路和未铺面道路,调查了4种路边环境（缓变区,附近区,中间区和非缓变区）的Pteleopsis suberosa苗木种群结构和其更新机制。沿道路平行线调查了2m×5m的203块样方,记录每个样方内的种苗总数和每个种苗的活枝数。通过评价基部和水平枝芽和挖掘地下根系来确定更新机制。结果表明,在4种路边环境中,单一主干和多主干苗木的总密度及各自密度都有明显的变化（p〈0.05）。所有苗木都是无性繁殖而来,根出条占98%,眠芽蘖和萌生各占1%左右。研究表明,铺面道路和未铺面道路缓变区中等水平土壤的干扰可以刺激Pteleopsis suberosa根出条更新 道路类型（铺面和未铺面）对苗木密度没有影响,但对路边立地的P.suberosa种群的萌生能力来说,道路类型是一个重要变量。P.suberosa是一个耐干扰的物种,受道路网干扰后可以通过根出条繁殖。 相似文献
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Influence of ground flora on Fraxinus mandshurica seedling growth on abandoned land and beneath forest canopy 总被引：1，自引：0，他引：1
Jinsong Wang L. Wu Xiuhai Zhao Juan Fan Chunyu Zhang Klaus von Gadow 《European Journal of Forest Research》2013,132(2):313-324
A better understanding of root/shoot interactions influencing seedling growth on abandoned land could yield insight into seedling regeneration and restoration of the abandoned lands. Field work had been conducted for 2 years (2008–2009) to investigate the impacts of neighbouring plants on Manchurian Ash (Fraxinus mandshurica) seedling growth under the canopy of an old secondary forest and on the abandoned land exposed to full solar radiation in North-eastern China. Four different interaction treatments were designed for the study: neither shoot nor root interaction, shoot interaction only, root interaction only, and both shoot and root interaction. The presence of either the shoots or roots of neighbours had a competitive effect, reducing the growth of the target seedlings at each site. The total competitive effect of roots and shoots of neighbouring plants was significantly less than the sum of root and shoot competition separately on the abandoned land, but this difference was not significant beneath the forest canopy. Root competition was more restraining than shoot competition on the abandoned land. Target seedlings adjusted their root morphology and growth rates in response to the competitive effects from different parts of the neighbouring plants. Our results indicated that the root:shoot ratios of the target seedlings at the end of the experiment were affected by neither initial tree size nor the competition from either above- or belowground at either site. The results also highlight the importance of reducing root competition in boosting seedling regeneration and forest rehabilitation on the abandoned land. 相似文献
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分析指出困难立地关键在于造林苗木成活困难,其难点包括种苗匮乏、地理位置偏僻、土壤水分有效性低、苗木蒸散强烈、苗木根系再生困难等,提出平衡根系容器育苗、圃内苗木耐旱驯化、保留原生植被整地、加大科研投入力度、转变观念等对策。 相似文献
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Larch tree species (Larix Mill.) are both ecologically and commercially valuable in their native range and are the focus of many restoration, afforestation, and commercial reforestation efforts in the boreal forests of the northern hemisphere. Land use change, shifting climate, and poor natural regeneration are making it increasingly difficult to establish the species; therefore, artificial regeneration is critical to ensure this timber species maintains its productive role on the landscape. New stocktypes are continually being developed to aid target seedlings for difficult sites, and critical, non-confounding evaluations of them are needed for target seedling development. This research evaluates the effect of container parameters on potential target seedlings. It examines tolerance thresholds of western larch (Larix occidentalis Nutt.) with respect to moisture and temperature status in the rhizosphere during early establishment. A suite of morphological measurements was used to assess seedling quality and relative performance following transplant. Modifying a commercially available container developed four distinct stocktypes of 111, 143, 175 and 207 ml that were paired with a volume-dependent nutrient regime at two culturing densities. Seedling phenotype was affected to a greater extent by container density than by container volume. Despite changes to container volume, root:shoot were found to be similar, indicating benefits of a tailored nutrient regime during nursery culture. Simulated field trials revealed that a low density growing arrangement improved post-transplant seedling growth, specifically root growth. Also, the 207 ml container facilitated greater growth in dry soil conditions compared to smaller containers. Lower (10 °C) rhizosphere temperature hindered root growth; however, seedling survival was 100 %, warranting the testing of earlier outplanting windows for this species. This evaluation of stocktype performance contributes to a greater body of work with this species and its congeners, which will ultimately benefit reforestation and afforestation efforts alike. 相似文献
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Response to canopy opening does not act as a filter to Fagus sylvatica and Acer sp. advance regeneration in a mixed temperate forest 总被引：1，自引：0，他引：1
Blandine Caquet Pierre Montpied Erwin Dreyer Daniel Epron Catherine Collet 《Annals of Forest Science》2010,67(1):105-105
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介绍川西云杉生态、生物学特性.根据保存的人工川西云杉林成活及生长情况,认为迪庆州寒温带地区是川西云杉适生区,川西云杉是高寒山区天然林采伐后理想的迹地更新树种.藉此,对其种子采集、圃地选择、播种育苗、苗期管理、造林地选择、整地、造林方法、抚育管理、病虫害防治等一系列苗木培育及造林技术进行了阐述. 相似文献