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毛竹林丰产年龄结构模型与应用研究 总被引：18，自引：3，他引：18
从南岭山脉以南的各毛竹产区中收集１３３０块高产林标准地,分别调查各度竹株数、胸径等测树因子与林分、环境因子,以用材林的竹秆产量,笋用林的笋产量为因变量,建立了产量模型：材用林Ｙ１＝－６２６９５．２４５＋６．５４１３Ｎ＋７０１２．５１９５Ｄ＋８．４５４８Ｘ１＋１１．０８７０Ｘ２＋１４．１５２０Ｘ３＋８．９９６９Ｘ４＋１４．５１５６Ｘ５笋用林Ｙ２＝６９７．５５６９＋０．２０５２Ｎ＋１．８５１４Ｄ－０．６４１４Ｘ１＋１．２４９３Ｘ２＋０．７６３６Ｘ３＋０．３７９０Ｘ４－０．８８３３Ｘ５（Ｒ１＝０．９８,Ｒ２＝０．９６）并结合生产要求,提出约束条件八组。应用该模型研究毛竹林最优化年龄结构,可以得到不同竹林质量、立竹量、立地条件、经营水平下最适宜年龄结构。能显著地提高林分的竹材和笋产量。 相似文献
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在福建省邵武市对椽竹、孝顺竹、坭竹等几种造纸用丛生竹进行秆节育苗试验表明，用平埋方法育苗显著优于斜埋和直插，竹蔸平埋效果更佳；不同竹种秆节育苗成活率存在明显差异；不同年龄的秆节育苗成活率在不同竹种间表现不同；不同育苗时间（３月或５月）的成活率差异不显著。竹秆不同粗细、不同部位、单节段或双节段育苗对比试验，结果以细秆（胸径２．５ｃｍ）、上部节段、双节段育苗成活率较粗秆（胸径４．６ｃｍ）、下部节段、单节段的为高。椽竹秆节径用不同激素处理后，处理间成苗率差异显著，以２，４－Ｄ２０ｍｇ／ｋｇ处理５ｈ和硼酸２０ｍｇ／ｋｇ处理２４ｈ的效果最佳。几种造纸用丛生竹秆节育苗试验＊张文燕周道三马乃训叶长青曹德友张华明 相似文献
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对闽南地区麻竹人工林地上部分生物量模型及现存生物量结构进行了研究。结果表明：以模型ｍ＝ａ·（Ｄ２Ｈ）ｂ对麻竹地上部分总生物量和秆生物量进行估计较为可靠,而对枝、叶生物量的估计需引进枝下高因子ｈ及模型ｍ＝ａ·Ｄｂ·（Ｈ－ｈ）Ｃ或ｍ＝ａ·Ｄｂ·［（Ｈ－ｈ）／ｈ］Ｃ。闽南地区麻竹人工林地上部分平均现存生物量为３９．５１８ｔ·ｈｍ－２,按年龄分配为：３年生生物量最高,占５９．１７％,其次为２年生、４年生、５年生;按器官分配为：秆生物量最高,占６２．８１％,其次为枝、叶。地上部分总生物量与秆生物量随竹秆高度增加而递减,枝、叶生物量自６～８ｍ区分段分别向秆基及秆梢递减 相似文献
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斑苦竹无性系种群生长发育规律的研究 总被引：8，自引：0，他引：8
本文通过对四川缙云山次生性斑苦竹无性系种群的取样调查，研究了笋芽的发笋规律，竹笋－幼竹的高生长和秆径生长动态，以及地上茎生长与气候因子的关系。结果表明：斑苦竹无性系种群的发笋盛期主要集中在６月中、下旬。无性系分株幼竹阶段平均高度呈Ｌｏｇｉｓｔｉｃ增长，回归模型为：Ｈ＝６２５。９７８１／１＋ｅｘｐ５．８５２６－０．１０１６ｔ（Ｐ〈０．０５）地上茎生长的主要制约因素为温度和湿度。高湿结合温暖有益于斑苦 相似文献
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时云南、广西等地细叶龙竹人工林进行调查,研究其竹秆特性,测量胸径、秆高、鲜重、含水量等指标．对部分指标做相关性检验,建立回归方程．研究结果表明,胸径与秆高、鲜重等因子显著相关,将不同立地等级竹材的胸径和秆高、胸径和秆重用直线、幂函数、多项式等方程进行拟合,拟合方程经F检验均达到极显著水平．造林密度越大,细叶龙竹每丛株数越少、胸径越小,秆高变化不大;在胸径相同的情况下,立地条件越好,细叶龙竹秆高越高,鲜重越重：细叶龙竹幼竹木质化程度低,其含水量高于成竹,雨季竹秆含水量较旱季高． 相似文献
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研究了雅竹、斑苦竹、满山爆、茶秆竹、大节竹和孝顺竹6种竹的相对外径、壁厚率、秆重等干形变化规律,分析了这6个竹种全长随胸径、秆重随胸径和全长的变化规律。结果表明,6个竹种竹秆累计重量的百分数与相对高度的关糸皆为三次多项式;6个竹种胸径与秆重的关系皆为幂函数W=aD~b,胸径和全长与秆重的关系都是W=aD~bH~c。 相似文献
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对新兴、丰顺、英德3 个地方的连片麻竹Dendrocalamus latiflorus 林分生长性状和竹材性状进行系统调查及分析比较,结果表明：新兴麻竹林分竹丛内竹秆数量多且竹秆年龄结构较为均衡,丰顺麻竹林分竹丛内竹秆数量很少且竹秆年龄结构不均衡,英德麻竹林分竹丛内竹秆数量少,竹秆年龄结构亦不均衡;160 m2 竹林中,新兴麻竹林分竹秆数量显著多于英德和丰顺,达263 株。一年生竹秆平均胸径以丰顺最大,其他两地较小;其他年龄竹秆平均胸径新兴、英德较大,丰顺最小;新兴、英德两地间麻竹林分竹秆胸径大小在所有年龄级中均无显著差异。3 个地区间麻竹竹秆的加工性状有显著差异,新兴麻竹竹秆分枝特别高、秆重大,英德麻竹秆高最大,分枝较高,因而两者均是较好的加工重组竹材的材料;丰顺麻竹材分枝特别低,但秆重较大,作为重组竹材的加工材料还是可行的。3 个地区的麻竹竹秆基本密度大致相同。 相似文献
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[目的]揭示屏边空竹的发笋、退笋和幼竹生长规律。[方法]定点观测了30丛屏边空竹周年的出笋、退笋、秆高及地径生长数据,运用SPSS软件分析评价了不同季节出笋及幼竹生长规律。[结果](1)屏边空竹笋期历时9个月左右(从9月至次年5月),根据出笋量的差异可分为初期、盛期和末期,春季最多而夏季最少;其中5丛(16. 67%)每季出笋,具有四季发笋的习性。(2)退笋率随着笋期逐渐增加,在出笋末期达到最高,为87. 76%。(3)笋-幼竹高生长约130 d完成,平均秆高达6. 36 m;呈现"慢-快-慢"的生长规律,生长曲线可用三次曲线方程描述:H=0. 806-0. 029t+0. 001t2-5. 894×10-6t3,R2=0. 980。(4)地径的生长历时16 d左右,平均地径为18. 50 mm,也呈现"慢-快-慢"的生长规律。[结论]屏边空竹发笋期长约9个月,具有四季发笋的习性,但各季节出笋量差异显著;秆高和地径呈现"慢-快-慢"的生长规律。 相似文献
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天然沙罗竹生物学特性和个体结构规律的研究 总被引：3，自引：0，他引：3
沙罗竹是我国南部热带地区分布较广，具有多种经济价值较高的大型丛生竹，本文论述了天然沙罗竹的分布和生物学特性，揭示了沙罗竹的秆形、秆壁厚度、秆材含水率的变化规律和个体结构特点，用实测材料拟合了秒结构因子之间相关关系的回归方程，编制了供天然沙罗竹林资源调查和规划使用的计量数表，为天然丛生林资源调查计量标准和科学经营的依据。 相似文献
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The bambooPhyllostachys bambusoides has been widely planted on riverbanks in Japan to protect against erosion. Recently, unmanagedP. bambusoides stands with high culm density are spreading along the banks of rivers. In order to study the impact of the bamboo stands
on riparian ecosystems, the relations between bamboo stand structure, light conditions and plant communities under the canopy
were examined. The study sites were set in bamboo stands with various culm densities in the middle of the Yahagi River in
Toyota, Aichi Prefecture. There was a close relationship between canopy coverage and relative photon flux density (RPFD) in
the bamboo stands. RPFD showed a highly negative relationship with total culm density, whereas no significant relation was
observed between the basal area of bamboo and RPFD. The total number of plant species in the bamboo stands increased with
decreasing culm density. Only a small number of tree saplings were observed in the stands with the highest culm densities,
while several species of forest floor herbs were found in the stands with lower culm densities. A number of invasive and annual
plants colonized the thinned stand. We suggest that moderate thinning and clearing of dead culms are needed to maintain biological
diversity in the bamboo stands on riverbanks. 相似文献
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We determine the relationships of culm surface area to other culm dimensions for one of the largest bamboo species, Phyllostachys pubescens Mazel ex Houzeau de Lehaie. A total number of 150 sample culms were collected from a stand of P. pubescens in Mt. Toshima, Kumamoto Prefecture, western Japan. The culm surface area for each sample was calculated, and then the relationships
of the culm surface area to basal area and product of diameter at breast height (dbh) and culm height were analyzed. The relationship
between culm surface area and basal area could be described successfully by the power equation, whereas there was a linear
relationship of culm surface area to product of dbh and height. Although the regression equations determined here would be
useful in estimating culm surface area of P. pubescens, it is necessary to select an appropriate equation depending on the purpose and available time and labor. 相似文献
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Xuanran Li Qijing Liu Yongrui Chen Lile Hu Fengting Yang 《Frontiers of Forestry in China》2008,3(1):16-23
Regressive models of the aboveground biomass for three conifers in subtropical China—slash pine (Pinus elliottii), Masson pine (P. massoniana) and Chinese fir (Cunninghamia lanceolata)—were established. Regression analysis of leaf biomass and total biomass of each branch against branch diameter (d), branch length (L), d
3 and d
2
L was conducted with functions of linear, power and exponent. A power law equation with a single parameter (d) was proved to be better than the rest for Masson pine and Chinese fir, and a linear equation with parameter (d
3) is better for slash pine. The canopy biomass was derived by adopting the regression equations to all branches of each individual
tree. These kinds of equations were also used to fit the relationship between total tree biomass, branch biomass, foliage
biomass and tree diameter at breast height (D), tree height (H), D
3 and D
2
H, respectively. D
2
H was found to be the best parameter for estimating total biomass. However, for foliage biomass and branch biomass, both parameters
and equation forms showed some differences among species. Correlations were highly significant (P<0.001) for foliage biomass, branch biomass and total biomass, among which the equation of the total biomass was the highest.
With these equations, the aboveground biomass of Masson pine forest, slash pine forest and Chinese fir forest were estimated,
in addition to the allocation of aboveground biomass. The above-ground biomass of Masson pine forest, slash pine forest and
Chinese fir forest was 83.6, 72.1 and 59 t/hm2 respectively, and the stem biomass was more than the foliage biomass and the branch biomass. The underground biomass of these
three forests which estimated with others’ research were 10.44, 9.42 and 11.48 t/hm2, and the amount of carbon-fixed were 47.94, 45.14 and 37.52 t/hm2, respectively.
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Translated from Chinese Journal of Applied Ecology, 2006, 17(8): 1382–1388 [译自: 应用生态学报] 相似文献
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[目的]探讨不同避光处理对麻竹笋苦涩味强度及单宁含量、形态与分布影响的机理。[方法]运用感官评定、光学显微镜、电子显微镜透射技术和磷钨酸-钨酸钠比色法,采用覆土(EP)、双层不透光套袋(CLPB)和自然生长(CK)3种不同处理,对麻竹鲜笋的口感品质进行感官评定,分析测定麻竹笋笋体单宁物质含量、形态和分布。[结果](1)不同处理的麻竹鲜笋的口感不仅均呈苦涩味,且苦涩味强度均表现为由麻竹笋的基部到笋尖逐渐增强的趋势,其苦涩味强度整体大小顺序为:CKCLPBEP。(2)麻竹竹笋壁中含有单宁物质的细胞(CWT)可被2%氯化亚铁溶液染成黑色,与不含单宁物质的细胞区别明显。(3)单宁大量分布在薄壁细胞内,少量在纤维细胞内,维管束中的筛管和导管细胞中无单宁分布。(4)单宁在薄壁细胞中主要分布于细胞质内,少量分布在液泡中,电镜下CWT中积累的单宁可分为絮状、颗粒状和块状3种类型。(5)不同处理的麻竹笋单宁含量为CK:1.15 2.67 mg·g~(-1),CLPB:1.03 1.43 mg·g~(-1),EP:0.36 1.13 mg·g~(-1),其相应的CWT密度大小顺序为:CKCLPBEP,3种处理不同部位的单宁含量与CWT密度大小均为笋尖中部基部。[结论]避光显著降低麻竹竹笋壁的苦涩味强度及单宁含量,自然光照下生长的麻竹笋苦涩味强度及单宁含量显著高于避光处理;光与竹笋中单宁物质分布和形态相关不显著,单宁形态仅与竹笋部位密切相关。覆土、套袋等避光措施可显著降低笋体单宁物质的含量,降低苦涩味,改善竹笋的口感品质,为培育低苦涩味麻竹笋提供科学的理论依据。 相似文献
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E. Shibata 《Journal of Forest Research》2003,8(2):0123-0126
To establish a sampling procedure for estimating the density of bamboo galls induced by Aiolomorphus rhopaloides Walker (Hymenoptera: Eurytomidae) in a stand of bamboo Phyllostachys heterocycla (Carr. Mitf.) (Monocotyledoneae: Gramineae), 5–12 bamboo culms were cut at random in late March of each year during 1998–2001
just before gall-maker emergence. The number of galls on the branches of each bamboo culm was counted. The spatial patterns
of the galls on the culms in the stand and on the branches within each culm were measured by Iwao's patchiness regression.
Galls were distributed contagiously both on culms and on branches. Current bamboo culms that emerged the previous summer did
not require sampling because no galls were observed on them. Except for this, there was no difference in gall density on young
and old culms, suggesting that it is not necessary to distinguish them. There were few (<4%) galls above 6 m height during
the 4 years. There was no significant difference in gall density up to 4 m and above 4 m, suggesting that branches up to 4 m
can be sampled with confidence. Kuno's two-stage sampling method at different precision levels showed that the number of culms
to be sampled varied with gall density. For example, at mean density m = 1.0 per branch when the number of sampled branches per culm is 10, a total of 24 culms is required to estimate gall number
at a precision level of D = 0.2, where D is the ratio of standard error to mean.
Received: July 10, 2002 / Accepted: November 25, 2002
Acknowledgments I thank Dr. K. Kamijo for insect identification. Thanks are also due to the members of the Laboratory of Forest Protection
for their kind help with the fieldwork. This study was supported in part by a Grant-in-Aid for Scientific Research (No. 11460068)
from the Ministry of Education, Culture, Sports, Science and Technology, Japan. 相似文献
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勃氏甜龙竹是一种优良的多用途竹种,近年来在许多适生区得到推广,其资源扩繁主要依赖于母竹移植。研究应用竹子生理整合性等生态学原理,以竹林林分结构调控为核心技术,采用不同林分结构组合,旨在探求笋苗兼用竹林经营模式。结果表明:(1)新造竹林有一明显的出笋数量和笋个体质量增长期,时间区段不同,前3a均快速增长,然后笋个体质量相对稳定,出笋数量仍较快增长。(2)竹笋产量主要影响因子是丛立竹数和立竹胸径,决定出笋数量和笋个体质量。出笋数量与丛立竹数正相关,与笋个体质量负相关。胸径与笋个体质量正相关,与出笋数量无相关。(3)合理的林分结构在450丛·hm-2时,丛立竹数为10株左右,胸径4～6cm。(4)经营类型经济效益明显,新造竹林第2年即有产出,第4年进入丰产期。 相似文献
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The effects of removing aboveground vegetation on survival and growth of Hondo spruce (Picea jezoensis var. hondoensis) saplings were examined in a dense dwarf bamboo (Sasa nipponica) field inside a deer-proof fence built in a degraded sub-alpine forest on Mt Ohdaigahara, central Japan. All bamboo culms
were removed within a radius of 1 m from each sapling in a plot of 0.6 ha (removal plot), whereas no culms were removed in
two control plots of 0.1 ha. We measured the height, crown depth, and main shoot elongation over 1 year for all spruce saplings,
culm height and cover ratios of dwarf bamboo growing around each spruce sapling, and the light levels above each sapling.
Removal of dwarf bamboo regulated the culm height and bamboo coverage until the following summer such that light conditions
improved. The mortality of saplings smaller than the average culm height was lower in the removal plot (0.89%) than in a control
plot (5.9%). After bamboo removal, sapling height growth was reduced with increasing bamboo cover in the previous year. Complete
removal of the aboveground portions of covering bamboo improved sapling survival while regulating elongation growth, possibly
because of the sudden increase in light intensity. Thus, controlling the extent of dwarf bamboo removal might be necessary
to facilitate the growth of spruce saplings to restore the forest. 相似文献
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Allometric equations predict tree seedling biomass from non-destructively measured variables such as stem diameter (D), height (H) and seedling silhouette area (A), measured by digital imaging. This study investigates whether one general allometric equation can predict biomass of radiata
pine (Pinus radiata D.Don) seedlings grown under three levels of photosynthetic photon flux density (PPFD). It also identifies which commonly
used variables (A, D
2
H or D
2) were the best for predicting seedling biomass under these conditions. Radiata pine seedlings were grown with constant daytime
(12 h d−1) PPFD = 500, 250 or 125 μmol m−2 s−1 for 11 weeks. Seedlings were randomly selected every 10 d for measurement. Analysis of covariance tested whether the relationship
between seedling biomass and A, D
2
H or D
2 varied for each PPFD level. PPFD levels influenced the relationship between biomass and A, D
2
H or D
2. As a result, “full” allometric models which varied with PPFD levels were more accurate and precise at predicting biomass
than “reduced” models which did not vary with PPFD level, although a “reduced” model using D
2 also performed well. 相似文献