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对刺槐采取挖除伐桩和保留伐桩2种不同采伐措施的更新试验效果表明:挖除伐桩的林地上其根蘖苗萌发数量平均比保留伐桩增加135%,苗高增加10.7%,地径增加75%。 相似文献
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辽东栎伐桩萌苗的发育规律 总被引:4,自引:0,他引:4
通过对黄土高原黄龙山林区辽东栎林固定样地连续6年的调查,研究间伐强度分别为13.4%(弱度间伐)和30.0%(强度间伐)的辽东栎伐桩萌苗的存活与生长规律.结果表明:1)间伐第1年,辽东栎伐桩均有萌生枝发生,每桩萌生枝数量和萌生枝高度在不同强度间无显著差异;2)萌生枝数量受伐桩高度和直径的影响,当伐桩高度较低时,萌生枝数量随伐桩高度的增加而增加,超过20cm后随之减少,呈三次抛物线关系;伐桩萌生枝数量随着伐桩直径增加呈现先增加后减少的趋势,直径30~50cm的伐桩萌生枝数量最多;3)伐桩萌生枝数量与最长萌生枝高度呈显著线性负相关,存在“萌生枝数量——高度权衡”现象;4)间伐第6年,伐桩的存活率为97.01%,强度间伐区萌生枝高度显著高于弱度间伐区;5)调查期间,辽东栎伐桩萌生枝数量逐年下降,伐桩产生的萌生枝数量越多,后期萌生枝死亡的数量也越多,表明伐桩能够自我稀疏,存在“萌代主”现象.在黄土高原地区,辽东栎伐桩萌芽潜力很大,应合理利用;间伐时伐桩高度应尽量低于20cm;伐桩直径在30~50cm更有利于其无性更新;间伐后伐桩应及时除蘖定株,促进萌生枝生长;间伐强度30.0%(强度间伐)更有利于辽东栎伐桩萌生枝的生长. 相似文献
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以秦岭南坡商洛地区栓皮栎次生林皆伐后的伐桩萌苗为研究对象,通过对不同生境条件下伐桩萌生幼苗监测,分析阴坡阳坡2个生境不同萌苗保留量对栓皮栎伐桩萌苗生长和生物量累积的影响.结果表明:1)皆伐后5年期间,2个生境条件下伐桩萌苗数量从伐后第2年开始减少,第4年数量趋于稳定.2)2个生境条件下,不同萌苗保留量监测表明,伐桩随着萌苗数量增多,萌苗平均基径、高度、冠幅减少.3)栓皮栎伐桩不同萌苗保留量监测表明:萌苗基径、高度均为阳坡>阴坡;与对照(自然生长)相比,确定萌苗保留量之后,伐桩萌苗基径、高度增长迅速,4年之后减缓;2个生境条件下栓皮栎伐桩萌苗随着萌苗保留量增多,高度、基径增长幅度降低.4)皆伐5年之后,2个生境条件下不同萌苗保留量栓皮栎伐桩萌苗器官生物量为主干>侧枝>叶片;随着栓皮栎伐桩萌苗保留量增多,伐桩萌苗生物量呈现先增多后减少的趋势,保留3个萌苗的伐桩萌苗生物量最大.萌苗保留量对栓皮栎伐桩萌苗生长和生物量累积影响显著;留萌栓皮栎伐桩保留1个萌苗有利于萌苗生长,保留3个生物量积累较多.选择不超过3个的留萌数量,更能实现不同目的的次生林培育. 相似文献
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东北东部林区次生林主要阔叶树种的萌芽更新规律 总被引:2,自引:1,他引:2
对固定样地调查,采用伐桩的径、高度、萌芽的数量、萌芽的生长情况等指标,分析东北东部林区主要阔叶树种的伐桩萌芽更新规律。结果表明:在一定的伐桩径范围内,伐桩萌生枝数随着伐桩径的增大而增多;增长到一定程度后随着伐桩径的增大而减少;得出不同树种萌芽能力较强的年龄范围的伐桩径级。对于不同阔叶树种,伐桩高与当年生萌生枝数量的关系存在着不同的变化规律,研究地点具有产生萌芽能力的阔叶树种可划为3种类型:对数型、直线型、指数型,阔叶树的萌生枝高生长与伐桩径和伐桩高无明显关系。第2年伐桩萌生枝的数量与伐桩径的关系在总体趋势上与第1年基本相同,同时次年仍有新的萌生枝产生,但数量很少。与第1年不同之处在于萌生枝开始死亡,一方面,伐桩产生的萌生枝越多,死亡的数量也增大;另一方面,第2年的伐桩存活率在不同种类树种间差别较大:水曲柳高达96·2%,槭树为23·3%,榆树类为21·8%。所探讨的树种在研究区域内都有“萌代主”的能力,并且不同树种以及同一树种不同年龄,“萌代主”的能力和单个伐桩保存的萌生大树的数量不同。 相似文献
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河北平原速生杨根蘖林培育技术试验研究 总被引:1,自引:1,他引:0
《河北林业科技》2013,(3)
该研究针对河北平原速生杨采伐更新手段单一、成本高、采伐后复耕趋势增加的现状,选择河北省平原地区速生杨主栽品种107杨、中林46杨、廊坊杨进行根蘖林培育技术试验研究,试验采用正交试验设计方法,对可能影响根蘖苗生长的因素进行了试验分析,确定了速生杨根蘖林留单株苗、苗高30~50cm时定苗、前2年进行农作物间作,第3年开始施肥、培土,冬季采伐覆土厚度5~10cm。填补了河北省平原地区利用速生杨伐根进行更新技术的一项空白。 相似文献
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街子乡根据刺槐根蘖萌生力强的特性,把朝阳村东沟山坡上的四十亩刺槐林(二十年生),甸子沟里九十亩刺槐林(十八年生),因生长缓慢而于八一年冬全部皆伐,八二年春挖去主根,并存东沟全部疏松了:E。现根蘖苗长势旺盛。其经验八三年在本乡毛集、北湾等村推广。全乡共采伐更新两条沟两个坡近320亩刺槐林。群众既分了卖原木椽材的现金,又分了 相似文献
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在采伐现场根据伐桩和相关信息测算已采伐林木蓄积,可采用的方法很多,通过不同测算方法的应用表明:用回归分析法建立根径、胸径、树高的回归方程,并用二元立木材积式计算采伐木蓄积,其结果比较真实可靠。 相似文献
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秦岭南坡不同生境条件下栓皮栎伐桩萌芽特性 总被引:1,自引:0,他引:1
以陕西省佛坪县的栓皮栎伐桩为研究对象,分析2种生境条件下栓皮栎伐桩直径和高度与萌苗数量、萌苗生长的关系,并通过2年跟踪观测研究伐桩的萌发能力。结果表明:1)阳坡伐桩上的萌苗数量多于阴坡,但阴坡的萌苗生长量(基径、高度和冠幅)优于阳坡;2)萌苗数量随伐桩直径增大先增加后减少,直径在15~25cm间的伐桩萌苗数量最多,萌苗生长量随伐桩直径增加先减小后增加;3)伐桩高度与萌苗数量的关系不明显,随着伐桩高度增加,萌苗生长量增加;4)萌苗基径随萌苗数量增多而减小,萌苗高度与之相反,阳坡萌苗数量与萌苗生长量的关系比阴坡密切;5)砍伐2年后,伐桩萌发能力和萌苗生长量均出现降低趋势。栓皮栎伐桩的萌苗数量不仅受到光照条件的影响,也受到伐桩直径和砍伐后时间长度的影响,但萌苗的生长则受到环境条件、伐桩直径、伐桩高度以及萌苗数量的共同影响。因此,择伐栓皮栎次生林中基径为15~25cm的个体最有利于林地快速恢复,在随后的经营管理中控制伐桩的萌苗数量并疏伐过密的萌苗丛有利于萌苗生长。 相似文献
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The effects of light, moderate and heavy branch pruning or lopping treatments (resulting in removal of 28-31, 56-60 and 80-82% of the foliage, respectively, unlopped control = 0%) were studied in 3-year-old black alder (Alnus glutinosa L. Gaertn.) plants. Within 24 h of lopping, transpiration rates decreased and water potentials increased. The effects of lopping continued for 48 days. The improved water status of the lopped plants enhanced water-use efficiency during the first 30 days. Regrowth was related to a combination of enhanced net assimilation rates during the first 30 days after lopping, use of current photoassimilates and stored carbohydrates in the roots (particularly in medium and heavily lopped plants) for the production of new leaf area, and delayed leaf senescence. The lightly and moderately lopped plants developed 62 and 57% more leaf area, respectively, than the unlopped plants, but total leaf area development was slower in the heavily lopped plants. Lightly lopped plants produced total biomass equivalent to that of unlopped plants, but the moderately and heavily lopped plants produced less biomass than the unlopped plants. During the first 30 days after lopping, there was a net loss of nodule dry matter and recovery to control values did not occur during the period of study. Immediately (24 h) after lopping, more (14)C-photosynthate was translocated to the roots of lopped plants than to the roots of unlopped plants. When a branch near the base of the main stem was fed (14)CO(2), (14)C-photosynthate translocation to the shoot increased with increasing intensity of lopping, at 50 days after lopping. 相似文献
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在昆明大马山树木园进行的云南拟单性木兰5年生苗木不同季节断根处理的苗木根系萌发生长效应的试验结果表明:云南拟单性木兰苗木新根的萌发与断根处理季节的气候因素有较大关系。其新根的萌发时间与温度紧密相关而与湿度关系不大;根系的萌发生长状况与断根季节的温度紧密相关,与降水量和蒸发量有一定关系,而与相对湿度关系不大。断根处理时的温度愈高,苗木新根的萌发时间愈早;断根处理时的温度、降水量愈高,其根系的萌发生长愈好。在滇中地区云南拟单性木兰苗木断根处理的季节宜在春、夏季进行,而不宜在秋季和冬季进行。夏季断根处理后3个月及6个月时其苗木每株有根系115.6根及178.4根,根长≥5 cm的侧根数为39.2根及84.0根,侧根分布土层的深度为26.0 cm及34.6 cm,侧根最长达14.4 cm及25.2 cm。与冬季断根处理后3个月及6个月时的苗木根系相比,新根数多108.0根及126.8根,根长≥5 cm的侧根数多39.2根及73.2根,侧根分布土层的深度多18.0 cm及6.8 cm,最长侧根长度多13.0 cm及15.2 cm。 相似文献
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埋干幼化处理对榛扦插生根的影响 总被引:1,自引:0,他引:1
为了解决榛扦插育苗生根率低的问题,提高榛育苗效率,以1年生‘巴塞罗纳’欧洲榛和平榛自根苗为试材,研究了埋干幼化、IBA处理和扦插基质对生根的影响。试验结果表明:在牛粪和壤土以2︰3为比例混合的基质中,用IBA质量浓度为500 mg/L处理,经过幼化处理的欧榛和平榛生根率分别为99.5%和96.3%,平均生根数为35.5和28.0条、平均根长61.9和44.5 mm,生根系数为218.9和119.2。埋干幼化处理可大幅提高榛扦插生根率。 相似文献
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Bonifacio Mostacedo Francis E. Putz Todd S. Fredericksen Armando Villca Turian Palacios 《Forest Ecology and Management》2009
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
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The main objective of our clonal propagation program is the production of high quality timber and faster tree growth. Teak
(Tectona grandis Linn. f.) is an important plantation species in the tropics but the demand of teak timber is increasing globally. Teak planting
stock is still produced from seeds of unselected elite genotypes which may lead to poor stand establishment. The number of
seeds per fruit and their germination ability are also variable and limited by several factors. Therefore an alternative method
i.e., clonal propagation is required for mass multiplication of elite trees. It is an established fact that the clonal propagation
or adventitious root formation in cuttings is markedly affected by several external and internal factors. Considering these,
an experiment was conducted on leafy soft wood shoot cuttings of 3-year-old hedged teak stock plants grown in a hedge garden
to study the effects of branch position and auxin treatment on adventitious root formation. A factorial completely randomized
design was used for experimentation. Coppice shoots were collected from basal, middle and upper positions of the hedge garden;
and mono-nodal leafy cuttings were prepared. These cuttings were treated with different concentrations of IBA and NAA; and
were cultured in a mist chamber for rooting where the relative humidity was maintained at 85 ± 2% with maximum and minimum
day-night temperature at 32 ± 1°C and 26 ± 1°C respectively. After 45 days the cuttings were removed from the rooting medium
and observations were made. It was observed that the rooting parameters viz., percent rooting and percent sprouting, mean
number of leaves, mean number of shoots and length, and mean number of roots and length per cutting were significantly influenced
by the branch position and auxin treatment. Treatment with 4000 ppm IBA increased percent rooting and percent sprouting whereas
NAA suppressed it. Treatment with 4000 ppm IBA also increased the mean number of leaves and shoots, and the length, and the
mean number of roots per cutting. The highest mean number of roots and length were observed in cuttings taken from the branch
emerging at the upper position followed by branches of middle and lower position. Cuttings of branches at a middle position
showed the highest values of percent rooting, percent sprouting, mean number of leaves and shoots and mean shoot length per
cutting. Furthermore, the interactive effect of branch position and auxin treatment on rooting and sprouting response was
also found to be significant. Overall, the findings of this investigation suggest that middle branch position in hedge plants
and 4000 ppm IBA can be made to induce maximum rooting and to produce high quality planting stock material for clonal forestry
program of teak. 相似文献
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Leena Hamberg Minna Malmivaara-L?ms? Irja L?fstr?m Henna Vartiam?ki Sauli Valkonen Jarkko Hantula 《European Journal of Forest Research》2011,130(1):99-106
We investigated the efficiency of three different methods to restrict sprouting in European aspen (Populus tremula L.) in regeneration areas of spruce in Finland. The methods compared were (1) traditional method (cutting at 10?C15 cm height) (2) cutting at 1 m height, and (3) fungus treatment (cutting at 10?C15 cm height, and mycelium of a white-rot fungus, Chondrostereum purpureum [Pers. Ex Fr.] Pouzar was applied to freshly cut stumps). The results indicated that the fungus treatment can restrict the emergence and growth of stump sprouts better than other methods, whereas cutting at 1 m seemed to yield the lowest numbers of root suckers. However, differences between the treatments were not significantly different (P values were > 0.05). For future experimentation, we suggest that the cutting of higher stumps to control the number of root suckers should be combined with application of C. purpureum to restrict the emergence and growth of stump sprouts. We also suggest developing more efficient C. purpureum isolates to control European aspen stump sprouting. 相似文献