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1.
在海南省琼海县进行了不同林龄、不同采伐方式对大叶相思萌芽更新影响的研究,同时比较了保留不同萌条数量的萌芽林生长表现。结果表明:(1)林龄对伐桩萌芽率没有显著影响,但对伐桩存活率及萌条的径、高生长影响显著或极显著。林龄越大,萌芽更新效果越差;(2)皆伐和隔行采伐对大叶相思伐桩的萌芽率、萌条数量和存活率均无显著影响,但对萌条的径、高生长影响极显著。试验证明对大叶相思林分施以隔行采伐通过萌芽更新建立复层  相似文献   

2.
辽东山区柞树成、过熟林萌芽更新问题的探讨   总被引:3,自引:1,他引:2  
通过对柞树林进行小面积皆伐与更新试验,结果表明,柞树成、过熟林小面积皆伐,萌芽更新效果良好。17a 生柞树萌芽林胸径达5 .8cm ,树高达7 .4m ,蓄积量66 .78m3/hm2 。柞树萌芽能力与采伐年龄和采伐季节有密切关系,林龄越大,伐后萌芽力越弱;树液流动季节采伐,萌芽力弱,反之较强。  相似文献   

3.
尾叶桉萌芽林经营技术及效益评价   总被引:1,自引:0,他引:1  
总结了尾叶桉无性系试验林采伐后进行萌芽更新及经营管理技术,介绍了前茬林木采伐方式、萌芽植株选留、萌芽林松土培蔸、合理施肥、病虫害防治等技术措施.并对萌芽林的经济效益进行分析评价。  相似文献   

4.
为探究尾巨桉短周期用材林采伐迹地二代更新方式,试验研究了6年生时尾巨桉的生长量和经济效益,结果表明:萌芽更新比植苗更新方式林分蓄积量更大,比增22.9%;净利润更高,比增34.4%。可见尾巨桉人工林采伐迹地二代萌芽更新切实可行,可以推广应用。  相似文献   

5.
通过不同采伐季节对巨尾桉二代萌芽更新效果的影响试验研究,结果表明:秋末至整个冬季是巨尾桉二代萌芽更新的合理采伐时期,而春、夏、秋初一般不宜采伐,若急需木材也只宜部分采伐。  相似文献   

6.
南洋楹是速生、多用途的用材树种。通过将南方冬季采伐习惯转移在春季采伐,可大大提高南洋楹萌芽率,促进萌芽更新成林;再加上降低伐根,培育出优质芽株,通过合理抚育,便达到萌芽更新的目的。  相似文献   

7.
磐安县黄檀林场杉木迹地更新试验简报   总被引:1,自引:0,他引:1  
对杉木采伐迹地用日本细叶花柏进行补到促进萌芽更新,其林分生长比杉木纯萌芽更新林分要提前1-2年都闭,且生长快,是杉木成熟林进行采伐迹地更新的一种方法。  相似文献   

8.
对丽水地区实验林场杉木采伐更新的调研结果认为:为有利于杉木萌芽更新,杉木的主伐年龄不宜过迟;伐桩高度必须降到20cm以下;采伐后应及时炼山;有条件的应提倡伐桩下山基部复土;对大径级伐桩可通过施肥促进萌芽率提高。  相似文献   

9.
通过10年试验和示范推广测试表明,用采伐泡桐成林树留下的伐根或伐桩萌芽更新效果很好。其中留桩萌芽更新林6~8年生时的单株材积为植苗林的1.38倍。萌芽更新以采伐6~9龄的成材树最适宜。该方法简便易行,省工省钱。  相似文献   

10.
林龄、采伐方式对大叶相思萌芽更新的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
在海南省琼海县进行了不同林龄、不同采伐方式对大叶相思萌芽更新影响的研究,同时比较了保留不同萌条数量的萌芽林生长表现,结果表明:(1)林龄对伐桩萌芽率没有显著影响,但对伐桩存活率及萌条的径、高生长影响显著或极显著。林龄越大,萌芽更新效果越差;(2)皆伐和隔行采伐对大叶相思伐桩的萌芽率、萌条数量和存活率均无显著影响,但对萌条的径、高生长影响极显著。试验证明对大叶相思林分施以隔行采伐通过萌芽更新建立复层林分是可行的;(3)保留不同数量萌条对萌芽林早期(1.5年生)的径、高生长有极显著影响,但对后期(4.5年生)的生长影响不显著。每棵植株伐桩保留4根萌条的萌芽林生物产量最高,更新效果最好。  相似文献   

11.
针对人工美黑×青杨成熟防护林存在的生长衰退、防护功能下降、急需更新改造等问题,利用杨树本身的繁殖特性,通过近10a的试验,从更新林分的条件、更新方式的选择、萌生植株管理、促进根蘖繁殖的覆土和灌溉措施以及投入成本等方面对美黑×青杨萌蘖更新进行了研究与分析,结果表明:根蘖繁殖更新效果明显优于萌芽更新和植苗更新,成活率提高13%,高生长提高33.7%-54.9%,单位面积造林成本较常规造林降低了54.6%,并提出了有效的根蘖繁殖更新配套技术。  相似文献   

12.
Sprouting can be an important mechanism of regeneration in harvested cypress (Taxodium sp.) wetlands; however, limited information exists on factors influencing sprouting. We examined the influence of harvesting practices, tree size, and site conditions on stump sprouting in eight pondcypress (Taxodium distichum var. nutans (Ait.) Sweet) wetlands in Florida, USA. Stumps were cut at three heights: 20 cm below high water level, at high water, and 40 cm above high water. Half of each site was harvested using a sawhead feller and the other half using shearhead. We monitored sprouting for 2 years post-harvest. Stump height affected first year sprouting, but the effect disappeared during year 2. Felling equipment did not affect sprouting; however, the shearhead caused greater stump damage. Sprouting declined with increasing parent tree size; percentage of stumps with sprouts after 2 years was 68% for trees 10–14 cm dbh and 28% for trees 20–24 cm dbh. Stump sprouting ranged among sites from 23 to 54% after 2 years. Results indicate that sprouting may be an important, but inadequate, form of regeneration. At sites with short hydroperiods, dense understories, and/or predominance of trees greater than 20 cm dbh, reduced sprouting may occur, and planting seedlings may be beneficial.  相似文献   

13.
A major impediment to the sustainable management of tropical dry forests in Bolivia is the scarcity of natural regeneration of commercial timber tree species. Where regeneration is present, true seedlings of many species are outnumbered by vegetative sprouts from roots, broken stems, and the stumps of felled trees. This study evaluates the importance of resprouts promoted by logging operations for the regeneration of commercially important canopy tree species. The objectives of the study were: (1) to characterize stump and root sprouting behaviors of canopy tree species harvested for timber; (2) to quantify the effect of logging on relative abundances and growth rates of stump sprouts, root sprouts, and true seedlings; (3) to relate the species-specific probabilities of stump sprouting to stump diameter and stump height; and (4) to explore how sprouting varies with the ecological requirements of canopy tree species. The study was carried out 1–5 years after logging of a privately owned land in a Bolivian tropical dry forest. Twenty-seven of the 31 species monitored resprouted at least occasionally, among which Centrolobium microchaete (Leguminosae-Fabaceae) and Zeyheria tuberculosa (Bignoniaceae) were the most frequent stump sprouters, and Acosmium cardenasii (Leguminosae-Fabaceae) and C. microchaete were the most frequent root sprouters. In all species the number of sprouts declined with increasing stump diameter and stump height. The probability of stump resprouting differed among species but did not vary consistently with stump diameter, except in Z. tuberculosa in which it declined. Approximately 45% of juveniles <2 m tall of canopy tree species originated from root or stem sprouts. Light-demanding species tended to regenerate more from seeds and root sprouts than from stumps. Seedling densities were higher in microsites opened by logging, while root and stem sprouts were equally common across microsites. Given their abundance and the fact that root and stem sprouts at least initially grew faster than true seedlings, we conclude that vegetative regeneration in this tropical dry forest is an important mode of post-logging regeneration especially for species that regenerate poorly from seed. Resprout management should be considered as a potentially effective strategy for the procurement of regeneration following logging, especially for species that do not readily recruit from seed.  相似文献   

14.
Sprout contribution to natural regeneration of Rhododendron arboreum following the tree felling for fuel wood and other purposes was studied in two disturbed sites (Paipraw and Falockchar) of Rhododendron forest in Arunachal Pradesh, northeast India. Cut stumps were categorized into seven girth and height classes to evaluate the effect of stump girth and height on production of sprouts. Effect of stump girth on survival of sprouts was also investigated. Results show that highest number of cut stumps is recorded in medium girth classes (50–80, 80–110, and 110–140 cm) in both Paipraw and Falockchar stands. However, density of cut stumps is higher in Paipraw (1 210 stumps·ha−1) than Falockchar (1 154 stumps·ha−1). Nevertheless, a little higher percentage of sprouting is recorded in Falockchar (18%) than that of Paipraw (15%). Similarly, maximum number of cut stumps is observed in the medium height classes (50–80, 80–110 and 110–140 cm) in both the sites. Cut stumps with lower girths show greater ability of sprouting than that of larger girth classes. Significant correlations are observed between stump girth and sprout number and between stump height and number of sprouts. Survival of sprouts also depends on stump girth. Survival of sprout shows significant variations between different sampling times in both the sites. Though overall sprout regeneration of R. arboreum is very poor, sprouts arising from lower girth classes survive well than those of higher girth classes. The findings of this investigation signify that stump sprouting is not playing much role in the natural regeneration of R. arboreum though it has the ability to sprout. Sprout survival is not adequate to restore a stand where indiscriminate tree felling is continued and the species may be considered as a poor coppicer. Therefore, regeneration through seeds and seedlings should be preferred over regeneration through sprouting.  相似文献   

15.
小美旱杨是河套灌区农田林网的主栽品种。结合天牛危害木的砍伐以及成熟林的更新,经过3年的试验,找到了萌芽更新最佳采伐时间及伐桩高度,同时结合萌芽力和生长量的调查,总结出了一整套萌芽更新技术措施,为萌芽更新的进一步推广奠定了基础。  相似文献   

16.
Subtropical forests in the Ryukyu Islands have been degraded by silvicultural practices, and thus their structural attributes are being shifted to other states dominated by a few tree species. This study clarified the mechanisms of the change, and examined the effect of clear logging on the resilience of a subtropical forest. Sprouting regeneration and typhoon disturbance were introduced into an individual-based model, SEIB-DGVM, for describing stand development and succession. The regeneration dynamics from young secondary to old-growth stands were reproduced fairly well with the model. Sprouting recruitment produced high stem density at the beginning of stand development, which caused a self-thinning trajectory following the −3/2 power law. In the late development stage after 70 years, tree species diversity fluctuated because of the regenerative response of sprouting species and the facilitatory effect of typhoon disturbance on the coexistence of subordinate species. The death of canopy trees because of typhoon disturbances reduced the dominance of Castanopsis sieboldii, and depressed its dominance in the understory. Consequently, the understory species could establish by virtue of fallen canopy trees, and tree species diversity increased at the stand level. Clear logging experiments in the model revealed that species diversity deteriorated, especially in the stand dominated by sprouting species. Resilience of subtropical forests was determined by initial species composition before clear logging. Our simulation results suggest that repeated logging drives subtropical forests with high species diversity to a stand monopolized by C. sieboldii.  相似文献   

17.
This study explores the sprouting characteristics of an evergreen broad-leaved forest after clear-cutting based on a survey of 1,893 stumps of 62 tree species in Okinawa, Japan. The sprouting capabilities of the stumps varied among tree species. The stumps of 60 species could produce sprouts, while those of the other two species could not. In 10 of the sprouting species, the mean sprout-stem number was higher than 4.0 stems per stump; nine sprouting species showed low sprouting capabilities. Additionally, Castanopsis sieboldii and Schima wallichii, the dominant species, exhibited high sprouting capabilities. Further, the sprouting capabilities varied with stump diameter at breast height (DBH). Stumps with a larger DBH tended to have a higher mean number of sprout stems per stump, higher DBH, and higher tree height than the smaller stumps. The forest stands regenerated by sprouting might recover into a tree community similar to that before clear-cutting.  相似文献   

18.
微圃植树法     
在分析育苗移栽成活率低及其原因、树木自然传种发芽机制和策略的基础上,提出微圃植树方法设想,并分析了微圃植树方法的优点。  相似文献   

19.
We followed the establishment and growth response of 13 commercial tree species to canopy opening, above-ground biomass removal, and experimental burns of low and high intensities in a lowland dry forest in Bolivia. Three patterns of response to treatments were observed among the most abundant commercial tree species. (1) Shade-intolerant species regenerated mostly from seed and had the highest survival and growth rates following high-intensity burns. (2) Shade-tolerant species were abundant in gap control and plant removal treatments. Treatments had little effect on the height growth of these species. (3) Individuals of root sprouting species were most abundant following plant removal and low-intensity burn treatments. Treatments had little effect on the height growth of these species. The wide variation in species responses to gap treatments found in this study not only reinforces the concept that species are distributed along a continuum of shade-tolerance levels, but that other aspects of species biology, such as seed dispersal type or sprouting behavior, further differentiate regeneration strategies. The variety of regeneration strategies found among the species at this forest site will require a flexible management scheme that mixes more intensive silvicultural treatments such as prescribed burning with less intensive treatments.  相似文献   

20.
文章以结构调控初期的城镇景观林为对象,调查测定间伐第1年主要树种的伐桩萌芽情况、萌枝数量、高度以及群落垂直结构,分析树种的萌枝能力及其群落的结构变化。结果表明,各树种的萌枝能力均较强,不同树种间存在极显著差异(F=129.5,P < 0.001),呈现"常绿树种产生数量多、植株矮小的萌枝,落叶树种产生数量较少、植株高大的萌枝"的格局。砍伐降低了林分密度,为冠层受压树种释放空间;同时,伐桩萌枝以其生长优越性快速恢复,占据高度3 m以下的空间,丰富了群落的垂直结构。因此,城镇景观林结构调控时,可通过砍伐并适当保留伐桩萌枝达到既控制林分密度又促进群落分层、维持群落和景观稳定性的作用。    相似文献   

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