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安吉县毛竹资源及其生物量研究 总被引：1，自引：1，他引：0
利用最新高分辨率DOM/DLG融合图,采用现地勾绘调查的方法对安吉县毛竹(Phyllostachys heterocycla cv.Pubescens)林资源进行调查,结果显示:全县有毛竹林面积55287.6hm2,毛竹总立株数17084.3×104株,为全省平均的1.2倍,毛竹生物量563.2×104t,单位面积生物量为101.9t/hm2,并推算出毛竹林乔木层年碳固定量为47.3×104t。从海拔高度看,毛竹林主要分于海拔250～650m,占全县毛竹林总面积的82.0%;从坡度看,主要分布于16～35°,占全县毛竹林总面积的87.2%。 相似文献
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毛竹天然分布于我国北纬 2 3°2 3′～ 32°2 0′,东经 10 4°30′～ 12 2°的广阔区域内 ,是我国分布最广、面积最大 ,经济、生态、社会效益最佳的竹种之一。毛竹林是 1年换叶、孕笋 ,下 1年发笋长竹 ,2年为一个周期。我国大部分竹产区都采用大小年毛竹林经营技术 ,这是广大竹农在变竹木混交林为纯竹林的过程中 ,经长期实践探索出来的一个既科学又简单的营林技术。但近期来 ,一些地方改大小年竹林为花年竹林 ,结果竹笋夜蛾、竹象鼻虫、竹螟、竹蝗虫、竹蚧、竹小蜂、竹蝉等竹类害虫迅速繁殖蔓延 ,使竹林遭到严重危害 ,笋竹产量明显下降。因… 相似文献
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钩梢对5年生毛竹竹材物理力学性质的影响 总被引：2，自引：0，他引：2
毛竹(Phyllostachys edulis)秆形通直、材性优良,是利用范围最广、经济价值最大的竹种(刘亚迪等,2008);但同时因毛竹秆高大、枝叶繁茂,是受风雪灾害影响较大的林种之一(肖本权,2003)。2008年初,我国南方遭受了严重的雨雪冰冻灾害,涉及湖南、安徽、浙江、江西等19个省(区、市),受灾森林面积1860万hm2(祝列克,2008),受灾中心区域为毛竹的主分布区,占我国毛竹林面积的70%以上。据统计,全国竹林受灾面积约400万hm2,其中80%为毛竹林(李潇晓,2008)。在竹林培育中,为应对雨雪冰冻灾 相似文献
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1 宣城竹子资源发展现状宣城位居皖东南 ,辖 5县 1市 1区 ,总面积 1 2 3 .3万 hm2 ,林业用地 6 9.3万 hm2 ,森林覆盖率为 5 4 .7%。全市拥有竹种 1 2属 71种 1 4变种 2 3变型 ,现有竹林 1 0 .44万 hm2 ,占全省竹林面积的 3 8.7% ,其中 :毛竹 8.3 1万 hm2 ,立竹蓄积 2 .3 8亿根 ,中、小径竹 2 .1 3万 hm2 ,立竹蓄积 3 .1 9亿根。主要经济竹种有 :毛竹、雷竹、毛环竹、燕竹、红壳竹、刚竹、早竹园、石竹、桂竹、高节竹等 (各县市区竹子资源分布情况见表 1 )。宣城市竹子资源的发展经历了几个阶段 (见表 2 ) ,从 1 96 3年到 1 984年 ,通过将毛… 相似文献
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福建省是我国毛竹主要产区 ,全省竹林面积 82 4万hm2 ,居全国第一。竹业是福建主要产业 ,是农村经济的重要组成 ,竹业发展的好坏关系到农村脱贫致富奔小康。福建省高度重视竹业发展 ,2 0 0 1年重点投资竹业开发二期示范工程 ,建设丰产示范基地。但近年来福建省毛竹林受到南京裂爪螨(Schizotetranychusnanjingensis)、竹缺爪螨 (Aponychuscorpuzae)严重危害 ,造成早期落叶 ,叶片焦黄似火烧状 ,竹笋产量大大降低 (张艳璇等 ,1 997a ;1 997b ;刘巧云等 ,2 0 0 0 ) ,制约了毛竹速生丰产示范基地建设。据调查 ,福建省毛竹害螨发生面积达 6 8万h… 相似文献
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安徽金寨县毛竹产业现状与发展建议 总被引：2，自引：2，他引：0
金寨县是安徽省的林业大县,资源禀赋得天独厚,竹林面积近2万hm2,其中毛竹林面积占竹林面积的67%。近年来,金寨县立足资源禀赋,大力发展竹产业,不断延伸竹产业链条,取得了一定成效。然而,目前金寨县仍存在许多制约着竹产业发展的障碍,文中分析了金寨毛竹产业现状、存在的问题及发展的优势,对毛竹产业的进一步发展提出了建议。 相似文献
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竹林主要害虫发生类型区划初步研究 总被引：1，自引：0，他引：1
笔者在安吉县对主要竹林害虫进行了发生类型区划研究。按害虫的发生频次高低对常灾区、偶灾区、安全区的概念作了明确阐述并制定了划分标准,然后以竹区村为单位根据毛竹、杂竹面积、出笋大小年,竹林占有林地百分比、竹林分布和农业气候、地形、地貌等因子,采用逐项打分计分定类的方法按村区划全县竹虫发生类型,经验证明总正确率达85%以上。 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