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利用木麻黄营造沿海沙地防护林,不仅符合适地适树的造林原则,而且也是保护和恢复全省海防林带生态工程的有效途径之一.因此持续性发展木麻黄沿海防护林、苗木品种和造林技术至关重要.文章介绍了木麻黄沿海防护林造林技术,并对以后的造林工作提出了一些建议. 相似文献
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坝上杨树防护林死亡原因浅析 总被引：3，自引：0，他引：3
该文介绍了河北省坝上地区杨树防护林的基本情况和杨树防护林的退化情况,对杨树退化死亡原因进行了分析,得出林木生理老化是主要原因,干旱、密度大、后期管护、造林方式或断根苗木使用也对森林退化有一定促进作用,其中可控因素密度、后期管护、苗木选择等原因的提出对于今后改进坝上防护林设计、营造和经营具有一定的指导意义,可以提高坝上防护林的营造经营水平,提高防护林的生态效益体现。 相似文献
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本文介绍了在农安县营造农田防护林的技术措施,主要是认真把握好苗木、栽植和幼林抚育的质量关,可有效提高农防林造林质量。 相似文献
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凤城县边门乡随着林业“一放二包”生产责任制不断深入人心,群众对植树造林要求越来越迫切。根据全乡植树造林总体规划,每年具体计划,有针对性地培育各种苗木。这样,既满足了营造用材林、薪炭林、经济林、防护林和绿化“四旁”对苗木的需要,又避免了苗木过剩现象的发生。他们主要做法是: 相似文献
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防护林建设是一个地区森林建设的重要组成部分,多种因素影响彰武县防护林退化严重。文章概况介绍了彰武防护林的现状,分析了立地条件差异大、降水量偏低、土壤沙化严重、有害生物灾害、树种选择欠佳和人为毁坏森林等防护林退化的主要原因,并提出了树种结构调整、提高苗木质量、提高水分利用率、有害生物防治和加大违法案件打击力度等退化防护林更新改造措施,以保证防护林的林分质量,发挥防护林的功能,为其他地区的防护林更新改造提供参考。 相似文献
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热带树种育苗技术现状与发展 总被引：3，自引：0，他引：3
根据热带地区环境特点和树种特性，较为系统地阐述了热带树种育苗技术研究的现状；介绍了热带树种的容器育苗、实生苗培育、无性繁殖以及微生物育苗技术；展望了热带树种育苗技术研究的发展前景。热带树种育苗技术研究尚是一个薄弱环节，需要热带林业工作者不懈地努力，探索合适育苗技术体系。 相似文献
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Mani Ram Moktan Georg Gratzer William H. Richards Tek Bahadur Rai Dawa Dukpa Kinley Tenzin 《Forest Ecology and Management》2009
Group selection tree harvest has been proposed as an ecologically sustainable silvicultural technique in mixed conifer forests of the western Bhutan Himalayas. To evaluate this silvicultural technique, we studied the ecological consequences of a group selection tree harvest in mixed conifer forests by assessing 127 circular plots (71 in logged and 56 in unlogged stands) in two forest management units (FMUs). Tree species composition and diversity were similar between logged and unlogged stands. Seedling density and height growth vary by species and were influenced by logging and microsites, with generally taller seedlings found in the logged versus unlogged stands. Early successional shade-intolerant species colonized logged stands. Seedlings growing on bare soil scarified by harvesting had medium vigour while seedlings growing on bryophyte mats showed good vigour in both logged and unlogged stands. Moist sites with a northerly aspect supported profuse conifer seedling regeneration, compared to sites with a dry southerly aspect. Damage to conifer seedlings from herbivore browsing was minimal. Conifer seedling density and height growth was negatively affected by competition from herbaceous vegetation, most notably Salvia officinalis. Group selection tree harvest in southern dry exposures in spruce-dominated stands is silviculturally unsuitable because it alters tree succession. 相似文献
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红丁香（Syringa villosa Vahl）是我省稀有的优良绿化树种，红丁香育苗的研究相对比较缺乏。我们通过近几年的育苗试验，初步总结出红丁香的育苗技术，为今后的育苗工作提供技术支撑。 相似文献
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To study spatial variation in natural tree seedling density and the relationship between variation in seedling density and
seed dispersal mode at a cleared site, we surveyed natural tree seedlings after the site preparation for planting in a coniferous
plantation cleared by a typhoon disturbance in 2004. The site was located near Sikotsuko Lake, Hokkaido, northern Japan. Twenty-five
tree seedling species were found and the mean seedling density was 9.8 seedlings/m2. Seedlings of non-animal-dispersed species (7.2 seedlings/m2) were approximately five times more abundant than those of animal-dispersed species (1.4 seedlings/m2), and 87% of all seedlings were current. The seedling density of non-animal-dispersed species (almost all wind-dispersed)
decreased with distance from a natural forest; however, this trend did not hold for animal-dispersed species (almost all bird-dispersed).
The spatial variation in seedling density was lower in animal-dispersed species than in non-animal-dispersed species. Seed
dispersal patterns and the viability duration of buried seeds likely affected the variation in seedling density by seed dispersal
mode. 相似文献
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Tree plantations are often used to compensate for the destruction and conversion of natural forests in the tropics. An important question is whether these plantations allow for the regeneration of indigenous tree species and are expected to transform into more natural forests in the future. To evaluate the potential of differently managed forest types for seedling recruitment of indigenous tree species we studied structural characteristics as well as tree and seedling communities in stands of natural forest, different types of tree plantations and secondary forest in Kakamega Forest, western Kenya. Forest types differed considerably in structural characteristics and tree composition with stands of natural forest significantly differing from all other forest types in vertical foliage height diversity and number of late-successional tree species. By contrast, total seedling species richness and number did not differ among the forest types. Yet, number of seedlings of late-successional species decreased from natural forest and plantations of a mixture of indigenous tree species towards monocultures and secondary forests while number of seedlings of early-successional species increased in the same order. A joint Principal Component Analysis (PCA) corroborated higher similarity among seedling communities than among tree communities. Our results indicate a convergence of recruiting seedling communities in different forest management types suggesting that tree plantations might buffer forest loss to a certain extent and may have the potential to develop into more natural forest over time. 相似文献
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This study examined the effects of framework trees, planted in 1998, and bird community on the natural recruitment of tree
seedling species in a forest restoration experiment designed to test the framework species method of forest restoration established
by Chiang Mai University’s Forest Restoration Research Unit (FORRU-CMU). Tree seedlings establishing beneath five framework
tree species: Erythrina subumbrans (Hassk.) Merr., Hovenia dulcis Thunb., Melia toosendan Sieb. & Zucc., Prunus cerasoides D.Don and Spondias axillaries Roxb., were surveyed. Five trees of each species were selected in the 8-year-old trial plots. Birds visiting each tree were
observed to determine possible seed dispersal activities. Thirty-six tree seedling species were found beneath the selected
trees, of which 11 were wind-dispersed and 25 were animal-dispersed. The population density of animal-dispersed tree seedlings
was higher than the wind-dispersed seedlings beneath all selected framework trees. The sample plots beneath P. cerasoides supported the highest population density of tree seedlings. Forty-nine bird species were recorded visiting the framework
trees between July 2006 and June 2007. Non-frugivorous birds were recorded more frequently than the frugivorous birds. The
effects of birds on seedling recruitment were different among each of the selected framework tree. Bigger trees, which attracted
high number of birds by providing food resources, roosting and nesting sites may increase the seed deposition more than smaller
trees with fewer attractants. 相似文献
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Tree regeneration in gap-understory mosaics in a subtropical Shorea robusta(Sal) forest 总被引：1，自引：0，他引：1
《林业研究》2019,(6)
Spatial variation in tree-regeneration density is attributed to the specialization of tree species to light availability for germination and growth. Light availability,in turn, varies across the gap-understorey mosaic. Canopy gaps provide an important habitat for the regeneration of tree species that would otherwise be suppressed in the understory. In subtropical forests, there is still a knowledge-gap relating to how canopy disturbances influence tree-regeneration patterns at local scale, and if they disproportionately favor regeneration of certain species. We aim to analyze whether canopy gaps promote tree regeneration, and tree species are specialized to gaps or understory for germination and growth. We sampled vegetation in 128 plots(0.01 ha), equally distributed in gaps and below canopy, in two subtropical Shorea robusta Gaertn.(Sal) forests in Nepal, recording the number of tree seedlings and saplings in each plot. We compared the regeneration density of seedlings and saplings separately between gaps and the understorey. The mean densities of seedlings and saplings were higher in the gaps at both sites;although there was no difference in the seedling density of the majority of the species between the habitats. No species were confined to either gap or understorey at the seedling stage. We conclude that gaps are not critical for the germination of tree species in Sal forests but these are an important habitat for enabling seedlings to survive into saplings. The classification of trees into regeneration guilds mainly based on germination does not apply to the majority of tree species in subtropical Sal forests. Our results reaffirm that gap creation promotes tree regeneration by favouring seedling survival and growth and can influence forest management for conservation, as well as for plantations. 相似文献