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壶瓶山国家级自然保护区森林植物群落类型及特征 总被引：6，自引：0，他引：6
对壶瓶山自然保护区的植被进行了研究,该区植被属于华中植物区系,地带性植被在森林分区上为中亚热带北部常绿阔叶林亚地带,属三峡武陵山雪峰山林区。主要类型有：低山针叶林、中山针叶林、中山针阔混交林、常绿阔叶林、常绿落叶阔叶混交林、落叶阔叶林、灌丛、灌草丛和草句。在分类系统上采用植被型组(Vegetation type group)一植被型(Vegetation type)一植被亚型(Vegetation subtype)一植物群系(plant formation)一植物群丛(Plant association)为分类等级,共分为5个植被型组,9个植被型,包括50个主要群系。 相似文献
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广东省连南板洞自然保护区主要有3个植被类型组、4个植被类型、12个群系和13个群丛。群落以常绿树种为主，垂直结构较为明显。海拔700m以下的丘陵低山为低山常绿阔叶林(部分为马尾松林、杉木林)，650～1050m为山地常绿阔叶林(镶嵌有落叶阔叶林)，1050～1450m为山顶常绿阔叶矮林，在1000m以上的山顶及裸露山脊即为灌丛草坡。具有典型的中亚热带常绿阔叶林的群落结构特征。 相似文献
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在调查大峡谷自然保护区植被和植物资源的基础上,对该区的植物区系和植被类型进行了分析.结果表明:该保护区的原生植被种类丰富,具有从南亚热带向中亚热带过渡的特点;区内植物区系成分复杂,组成以热带-亚热带和热带成分为主,热带性分布的植物类群甚多,使得区内沟谷常绿阔叶林具有某些雨林特征,小型板根、茎花现象、附生植物、藤萝密布等随处可见,而在其它中亚热带地区这种现象很少见;保护区内的植被有8个类型,包括具有雨林特征的常绿阔叶林、山地常绿针阔叶混交林、山顶常绿阔叶矮林、崖壁常绿矮林、亚热带针叶林、亚热带竹丛、亚热带灌丛草坡等,以及假苹婆、榕树林等18个群系;大峡谷自然保护区多样性植被类型具有与其独特的地形地貌相适应的特点. 相似文献
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崀山丹霞地貌区植物群系特性研究 总被引：1，自引：0，他引：1
采用线路与标淮地调查相结合的方法,研究了崀山丹霞地貌区森林植物群系特性。结果为:峎山有10个植被型、72个植物群系,其植被主要是中国、日本共同的属和众多的中国特有属树种为组成特征的森林植被,也有一定比例东亚—北美成分,在结构组成上表现出中亚热带常绿阔叶林的特点;丹霞单体出現特异的群系分布格局和"植被孤岛效应",不同发育期丹霞地貌上分布着不同演替系列上的森林植被类型;发現分布于丹霞赤壁下部的1个新的植被型(藤本植被型)和2个丹霞赤壁面上由崀山特有物种为建群种组成的持有植物群系(新宁毛莨群系,崀山唇柱苣苔群系)。 相似文献
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常绿阔叶林是亚热带地带性植被类型。在广州流溪河上游流域，分布有少量的保存较好的常绿阔叶林，主要见于海拔200m以下的地区。由于分布面积狭小，因此其植物区系并不丰富。种子植物科、属的地理成分表明，该植被型的区系具有显的热带、亚热带性质，同时具有一定的温带成分，东亚和北美间断分布、泛热带分布和旧世界热带分布对该森林的区系性质影响很大。常绿阔叶林植被及其区系都是在中生代末起源于华夏古陆，其中少量的落叶成分也是干旱促成、华夏起源的。 相似文献
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澜沧江省级自然保护区位于澜沧江中游临沧市境内。该区域植被类型随海拔升高而呈垂直分布规律。在以往的研究中忽视了澜沧江两岸低海拔区域植被的研究。文章以临沧市临翔区邦东乡沿江两岸低海拔植物群落为主要对象,分析该区域植被类型及其物种组成,以期为该区域生物多样性管理提供依据。研究发现,在沿江两岸海拔750~1400 m区域,共计发现7个植被型、8个植被亚型、8个群系及8个群落类型。除季风常绿阔叶林外,其他7个植被亚型均为本次调查新发现,其中热带季雨林与暖热性针叶林是研究区域主要的植被类型,而暖热性针叶林与季风常绿阔叶林则受破坏较大,分别产生暖热性稀树灌木草丛和干热性稀树灌木草丛,而干热灌丛则小面积分布。并根据澜沧江周期性枯水期出现的狗牙根群落,新提出河流消落带植被类型。 相似文献
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保护区共划分8个植被型、12个植被亚型、14个群系,是云南省中山湿性常绿阔叶林的典型分布地,植被水平基带为高原南部季风常绿阔叶林,垂直带层次丰富,包含了从南亚热带到山地寒温带的植被系列.其植被分布特点为:①中山湿性常绿阔叶林面积大,分布典型;②有我国大陆分布最南的苍山冷杉林;③云南省内分布最高的刺柏林;④植被垂直分布特征明显等. 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