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1.
哀牢山徐家坝中山湿性常绿阔叶林区系结构 总被引：3，自引：0，他引：3
本文根据组成森林的区系(地理)成分,着重讨论了徐家坝湿性常绿阁叶林的区系组成,森林的性质和区系起源。讨论表明组成湿性常绿阔叶林的区系以中国喜马拉雅成分为主,以西南特有种为特征和热带东南亚(印度、马来西亚)北缘成分共同组成,并在垂直结构中形成梭状图式。具亚热带和热带北缘区系特性及起源古老的特点。与邻近森林区系的关系表现出与中国喜马拉雅南部及热带东南亚北部山地森林区系更近亲。结构5层,8种层片。所有这些表明该森林是亚热带山地垂直带上部典型的常绿阔叶林。由于生态环境特殊与同类其他中山湿性常绿阔叶林不同。 相似文献
2.
红毛丹栽培技术 总被引：6，自引：0，他引：6
红毛丹NepheliumLappaceum,为无患子科韶子属常绿乔木果树,是著名的热带水果。原产马来群岛,在东南亚各国栽培较多,中美洲、非洲、大洋洲一些国家和美国均有栽种。世界上红毛丹栽培面积较大的是泰国,其次是马来西亚,泰国属热带季风气候区,马来西亚属热带雨林气候区,因其优越的热带气候特点使泰国、马来西亚成为红毛丹的主产地,泰国种植面积达10万hm2,年产130万t左右,均占世界总量的70%以上[1]。红毛丹在国际市场上一直供不应求,价格稳定。1964年我国海南省保亭热作所引进种植,1995年起大规模推广种植,到2002年,种植面积已达2700hm2。云南省… 相似文献
3.
甘肃野生花卉的基本特征及特点 总被引：1，自引：0，他引：1
对甘肃省野生花卉调查研究后认为,甘肃野生花卉的基本特征依据产地可归纳为4种气候类型,即荒漠气候型、高寒高山气候型、亚热带气候型和大陆东岸气候型(中国气候型)。其特点是：分布不均匀;温带花卉占主导地位;种类繁多,类型多样;珍稀濒危植物种类丰富;报春花属、龙胆属、杜鹃花属、柽柳属、马先蒿属野生花卉有特色。 相似文献
4.
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
5.
福建省木兰科植物研究 总被引：1，自引：0，他引：1
福建地处中国的东南沿海,属亚热带海洋性季风气候区,地带性植被为亚热带常绿阔叶林,十分适合木兰科植物的生长、繁衍、分化、发展。福建现有木兰科植物6属25种,另引入栽培10余种,这些物种由中国西南的现代分布中心经南岭走廊迁移、扩散进入福建后,在适生环境下生长、繁衍并分化出地域性特有种3种。 相似文献
6.
元江自然保护区半湿润常绿阔叶林的群落学及种子植物区系特征 总被引：2，自引：0，他引：2
在元江自然保护区所保留的半湿润常绿阔叶林内,经作样地调查,共记录到种子植物56科,115属,194种,蕨类植物13科,17属,20种;其半湿润常绿阔叶林的空间层次分明,可分为乔木上层、乔木下层、灌木层、草本层和层外植物,表明在哀牢山海拔高度1 900～2 200 m的地带,仍保存着较完整的半湿润常绿阔叶林植被类型.对其种子植物区系特征的分析表明,该植被类型热带性质的属要多于温带性质的属;而在种的结构上, 只有热带亚洲成分、东亚-喜马拉雅成分及中国特有成分能够贯穿于各层次之中; 其区系成分以东亚-喜马拉雅和中国特有成分占优势, 同时热带亚洲成分也占有相当的比例, 说明在其种子植物区系上具有由亚热带向温带过渡的性质; 而从中国种子植物特有种作进一步分析,则表明其在种子植物区系上具有过渡性质.与澜沧江自然保护区的半湿润常绿阔叶林相比较,澜沧江以硬斗石栎和木果石栎为主要优势种,而元江自然保护区的半湿润常绿阔叶林则以元江栲和短柄石栎为主要优势种,且分布的海拔高度偏低;与邻近的无量山自然保护区,海拔高度相近的同类半湿润常绿阔叶林相比,其主要优势种相同,说明两地的半湿性常绿阔叶林具有同源性. 相似文献
7.
通过对江西三百山自然保护区植被调查研究,结果表明三百山自然保护区区系成分复杂,以热带和亚
热带区系成分最多。保护区的主要植被类型是常绿阔叶林,从其组成的主要优势树种壳斗科Fagaceae、金缕
梅科Hammamelidaceae、木兰科Magnoliaceae、山茶科Theaceae和樟科Lauraceae 等树种来看,体现了典型的
亚热带森林特点。 相似文献
8.
林祁 《中南林业科技大学学报(自然科学版)》1999,(3)
湖南木兰科植物有 ６ 属 ３４ 种 ２ 变种,分布于 ４８ 个县,多生长于海拔 ５００～１５００ ｍ 的山地阔叶林中．依据湖南木兰科植物的地理分布,结合系统分类和植物区系资料,经分析和推论得知：（１）湖南木兰科植物种质资源丰富,以中国特有成分为主,它们与毗邻省（区）的种类关系密切;（２）湖南木兰科植物区系表现为多种区系成分的过渡与汇集,即华中、华东、华南和滇黔桂４ 个区系成分的交汇、混杂和过渡;（３）湖南木兰科植物的多数种类是从湖南西北至西南以外地区迁移扩散而来,少数种类是在本省西北至西南地区及其周边省区分化形成;（４）湘西北至湘西南地区是湖南木兰科植物的现代分布中心与现代分化中心．另外,还编排了湖南木兰科植物分类检索表 相似文献
9.
甜槠林是我国亚热带分布最广的常绿阔叶林类型之一,是我国典型的地带性植被和顶极群落类型。本文全面系统地研究了湖南甜槠林的分布、生境特征、群落结构及区系组成,并讨论了立木生长规律。为进一步保护利用亚热带常绿阔叶林提供了较为系统的资料和理论基础。 相似文献
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11.
《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
12.
《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
13.
《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
14.
《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
15.
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
16.
《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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18.
《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
19.
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
20.
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