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为指导培育市场急需的赤皮青冈容器大苗,以2a生赤皮青冈为研究对象,设置4个不同氮素水平(每株施氮 CK 0g,A10.144 9g,A20.283 8g,A30.425 7g),研究不同氮素添加量对赤皮青冈容器苗木生长量的影响。结果表明：苗高、地径、叶总数、叶片长度与宽度以及地上与地下生物量,都表现为随着氮素添加量的增加先增加后减小趋势;A2处理对苗高、单株叶片数以及叶片、茎、根系生物量最有利,A1 处对地径以及叶片长度与宽度最有利。按照本研究采用的营养土来源和配比,利用2a生幼苗培育赤皮青冈容器大苗时,建议每株施氮0.283 8g或0.144 9g。 相似文献
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以赤皮青冈1年生轻基质网袋容器苗为对象,采用析因试验设计,研究不同基质配比和缓释肥施用量对其生长及根系发育的影响,并提出优化育苗方案。结果表明,除根系发育的缓释肥效应不明显外,赤皮青冈容器苗生长对基质配比和缓释肥施用均较为敏感。随着基质中泥炭比例的增加,地径、生物量及根系指标值均呈现显著的先增高再降低现象,当泥炭所占比例为60%时,地径、各部位生物量及根系发育指标均达最大值。随着缓释肥施用量增大,苗高、生物量和根体积先升高再降低,当缓释肥施用量为2.5 kg·m-3时,相应指标值最大,且显著大于其它缓释肥施用处理,但其根系形态指标如根长、根表面积和根直径的缓释肥效应较小,不同缓释肥施用量间差异不显著。综合基质配比和缓释肥施用量两因素效应及其交互效应,采用模糊数学隶属函数法,为赤皮青冈1年生容器苗优选出最优育苗方案及备选的其它4种较优育苗方案。最优育苗方案为配比基质中泥炭:谷糠体积比6:4,并增施2.5kg·m-3缓释肥爱贝施(Apex)。 相似文献
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[目的 ]基于不同缓释肥添加梯度和接种菌根菌互作试验,分析缓释肥添加和接种菌根菌对赤皮青冈1年生容器苗生长性状和养分状况的作用规律,以提高赤皮青冈容器苗的菌根化育苗水平。[方法 ]采用裂区试验设计,主区为菌根菌处理,分为接种(育苗容器中间部位注射浓度为36.28 mg·mL-1的彩色豆马勃10mL)与不接种2个处理;副区为基质缓释肥添加处理,设置5个缓释肥添加梯度(1.50、2.25、3.00、3.75和4.50 kg·m-3)。[结果 ]接种菌根菌对不同缓释肥梯度下1年生赤皮青冈容器苗生长均有促进作用,缓释肥添加和接种菌根菌对容器苗总生物量和P利用指数有显著的互作效应。接种菌根菌后,赤皮青冈容器苗苗高、地径、高径比、总生物量、总根长和根系直径等生长性状相比不接种分别增加18.70%、7.16%、10.75%、24.55%、1.02%和18.47%,N含量、N吸收量和N利用指数、P吸收量和P利用指数分别增加2.04%、27.10%、27.67%、19.72%和30.52%,P含量降低2.94%,除总根长和N、P含量外各生长性状和养分状况指标接... 相似文献
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《浙江林业科技》2017,(4)
对浙江省龙泉市营造3~4年生赤皮青冈Cyclobalanopsis gilva,福建青冈C.chungii和小叶青冈C.myrsinifolia的58个家系子代幼苗进行生长性状测定,分析生长性状、遗传变异及生长性状间相关性,并对其进行早期选择。结果表明,不同青冈及其家系间生长性状存在丰富的变异,各家系4年生幼苗多数生长性状间呈显著正相关(0.05水平),且树高和当年抽梢高存在显著的表型相关,其中遗传相关和环境相关均达到显著水平。初步筛选出13个生长较优的青冈家系,分别为宁赤3,宁赤2,宁赤4,宁赤10,福赤8,宁赤6,庆小11,宁赤7,庆小9,福赤7,龙小6,庆小1和福赤5。多数为赤皮青冈家系,表明赤皮青冈早期生长优于小叶青冈和福建青冈。4年生的生长性状测定表明,生长性状的早期选择存在较明显的稳定性。 相似文献
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人工针叶纯林成熟林分主伐择伐后,对20株/亩(A)、30株/亩(B)、40株/亩(C)3种不同保存密度林冠下采用赤皮青冈与米槠2年生无纺布营养袋苗造林效果对比,造林2年的生长量调查结果表明：不同保存密度林下套种的赤皮青冈与米槠造林成活率、地径、高度、冠幅4项指标均以A最高,平均造林成活率达96.4%,赤皮青冈平均地径达2.21 cm,平均高达177.7 cm,平均冠幅达106.0 cm;米槠平均地径达2.07 cm,平均高达224.6 cm,平均冠幅达133.6 cm; 4项指标大小次序为A>B>C。 相似文献
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《浙江林业科技》2016,(3)
2014-2015年,在浙江省缙云县对赤皮青冈(Cyclobalanopsis gilva)、闽楠(Phoebe bournei)、木荷(Schima superba)3种树种进行容器苗和裸根苗在上、中、下3种不同坡位造林试验,并研究其对造林成活率、地径及树高生长量的影响。结果表明:不同树种容器苗造林后树高生长量、地径生长量及造林成活率均显著高于裸根苗;坡位对不同树种造林成活率、地径生长量和树高生长量的影响均表现为下坡中坡上坡;不同树种之间,木荷在各坡位造林的成活率均高于赤皮青冈、闽楠,闽楠则在地径生长量和树高生长量上优势最明显。试验表明容器苗造林可以有效提高造林成活率,下坡造林有利于幼苗更好生长。 相似文献
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于2019—2020年,在浙江省龙泉市林业科学研究院设施大棚,研究不同补光时长(3、6、9 h,以不补光为对照)对青冈、浙江樟、浙江楠3种阔叶树1年生容器苗生长的影响。结果表明：不同补光时长下青冈、浙江楠容器苗的地径、苗高、叶下高、叶片总数、最大叶片长度、最大叶片宽度等生长指标存在极显著差异;浙江樟容器苗的地径、苗高、叶下高、最大叶片长度、最大叶片宽度等生长指标存在极显著差异,而叶片总数差异显著。不同补光时长对青冈容器苗生长的影响程度大小依次为9 h>6 h>CK>3 h,对浙江樟、浙江楠容器苗生长的影响程度大小均为6 h>3 h>9 h>CK。综合结果表明,青冈容器苗的最佳补光时长为9 h,浙江樟、浙江楠容器苗的最佳补光时长为6 h。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(5):427-435
In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads. 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(1):53-61
This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1):15-27
The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions. 相似文献
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本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(2):131-138
The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(5):472-479
Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken. 相似文献
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Srisuda Thippayarugs Banyong Toomsan Patma Vityakon Viriya Limpinuntana Aran Patanothai Georg Cadisch 《Agroforestry Systems》2008,72(2):137-148
In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic
or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts
(stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea
(Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content
as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest
N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized
to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea,
largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for
N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant
components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N
released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures
were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality
components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in
the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols.
Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest
age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its
components are mixed. 相似文献
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A. Rigueiro-Rodríguez M. R. Mosquera-Losada E. Gatica-Trabanini 《Agroforestry Systems》2000,48(3):245-256
The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste
disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization,
(2) milk sewage sludge at 40 kg N ha−1 target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two
pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha−1. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1); (2) Lolium perenne L. var. Tove (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea
(Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m2, with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect
on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage
sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but
affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral
systems.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献