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科尔沁沙地5种造林乔木的抗旱特征研究 总被引：1，自引：0，他引：1
《辽宁林业科技》2017,(4)
为探讨科尔沁沙地造林树种对干旱环境的适应能力,采用控水法观察糖槭、五角枫、大叶白蜡、桃叶卫矛和稠李5种科尔沁沙地典型造林乔木的叶片形态,测定相对水分亏缺、丙二醛、可溶性糖和相对电导率的变化,运用隶属函数值法进行植物抗旱性综合评价。结果表明:5种乔木的综合抗旱性排序为桃叶卫矛五角枫大叶白蜡糖槭稠李;桃叶卫矛和五角枫抗旱性较强,更适合在科尔沁沙地困难立地进行野外造林。 相似文献
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《防护林科技》2015,(11)
以浑河上游水源涵养林为研究对象,通过对4种典型林分类型的树种组成、枯落物持水特性和土壤持水特性进行的研究,结果表明:各类型林分的树种组成复杂程度顺序为核桃楸+花曲柳+五角枫混交林冷杉+白桦+五角枫针阔混交林辽东栎+五角枫天然林人工日本落叶松纯林,阔叶混交林和针阔混交林树种结构稳定性更强;不同林分类型枯落物和土壤最大持水量的大小顺序为核桃楸+花曲柳+五角枫混交林(4 003.38thm-2)冷杉+白桦+五角枫针阔混交林(3 838.54t hm-2)辽东栎+五角枫天然林(3 444.15t hm-2)人工日本落叶松纯林(3 208.85t hm-2)。 相似文献
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槭树属树种色彩艳丽,品种众多,人们常把具有观赏价值的枫类种苗统称为红枫,而且总把元宝枫与五角枫、鸡爪槭与青枫或者羽毛枫、糖槭与美国红枫、复叶槭与白腊等树种名称混为一谈。本文对几种树种的生物学特性、生态特性进行了详细的描述和区别。 相似文献
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三种槭树叶的组织结构与抗虫性的关系 总被引：1，自引：0，他引：1
为了研究槭树叶的组织结构与抗虫性的关系,采用石蜡切片的方法,对复叶槭、五角枫和挪威槭3种槭树叶的组织结构进行了比较研究。数据分析结果表明:3种槭树科植物的叶片总厚度、叶片表皮气孔密度和栅栏组织密度的大小排列顺序均为:复叶槭<五角枫<挪威槭,方差分析结果表明这3项指标均差异显著,且大小排列顺序与植物的抗虫性顺序是一致的。而叶柄木质部与韧皮部厚度比值大小排列顺序为:挪威槭<五角枫<复叶槭,方差分析结果表明此指标差异极显著,且大小排列顺序与植物的抗虫性顺序是相反的。此外,3种槭树科植物叶片表皮及主脉韧皮部中的内含物与植物的抗虫性也可能存在某种联系。 相似文献
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<正>花曲柳(Fraxinus americana L.)为木樨科白腊属,落叶乔木。小叶通常7枚,卵状长椭圆形,缘具钝锯齿或近全缘,顶端叶较大,叶面具光泽。花单性异株,翅果生于小枝。树干通直,树皮灰褐色,纵裂。展叶时间较晚。花曲柳幼时较耐荫,长大后喜光。幼树植于树荫或林间空地,较植于光照充足处的树生长快,适宜阳性树种疏林地的补植或多树种混交造林。幼树生长缓慢,10 a 左右长势渐快。花曲柳抗逆性较强,耐寒冷,耐高热,不择土壤,耐水湿与干旱, 相似文献
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金叶复叶槭生长季节芽接和绿枝嫁接试验 总被引：1，自引：0，他引：1
金叶复叶槭为槭树科槭树属绿化树种,叶片金黄靓丽,抗寒冷,耐污染,在沈阳地区生长表现优异,是优良的行道树和绿地点缀树种。为探讨金叶复叶槭快速繁育技术,进行了无性繁殖试验,结果表明,＂T＂形芽接成活率最高,绿枝劈接以半木质化新梢为砧木、半木质新梢为接穗的嫁接效果较好。 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