首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Wu Gang  Li Junqing 《林业研究》1998,9(4):290-291
The distribution, regeneration and succession ofFagus in China were systematically analyzed in comparison with those in Europe and in northern America. The results showed that it was very likely that China was the distribution center ofFagus, which originated in eastern Asia, migrated into northern America and then into Europe. Distribution ofFagus in China is relatively independent with seven species. The main reason for wide distribution ofFagus in Europe, but unitary species, is possibly the influence of the climate in Quaternary Period, and also related with influence of the ocean climate. This study was supported by National Natural Sciences Foundation of China (39500116 and 39670145) (Responsible Editor: Chai Ruihai)  相似文献   

2.
Beech trees occur in significantly lower latitudes in continental East Asia than in Europe and North America. They are common deciduous trees in the deciduous forests of the temperate zone in Europe, the eastern part of North America and Japan. In continental East Asia, however, they are absent in the deciduous forests of the temperate zone, but occur in the forests of mountains in the moist subtropical zone, south of 34° Northern Latitude. The lower limits of their distribution in these mountains show a significantly different pattern from the usual distribution pattern of plants and vegetation: it declines as the latitude decreases. The altitudinal belts of beech species lie higher in the northern than in the southern parts of their distribution areas in China. Based on an analysis of the climate and the phenology of these deciduous trees, we show that the prevailing monsoon conditions are the main factor affecting the distribution of the Chinese beech species.  相似文献   

3.
绣线菊属植物资源及其在园林中的应用前景   总被引:6,自引:0,他引:6  
综述我国绣线菊属植物原种和变种资源及其分布,介绍常用的种类、栽培品种及其优良性状、园林应用状况,并推荐一些优良的绣线菊植物种类,阐述绣线菊属植物在园林中的应用前景.与英、美、德等国家对绣线菊的引种和应用相比,我国对绣线菊属植物的深入研究和园林应用亟待加强.  相似文献   

4.
杨柳科植物的分类与分布   总被引:14,自引:5,他引:9  
杨柳科包含2个亚科、5个属、约500种;杨亚科由杨属和胡杨属组成,柳亚科由原柳属、钻天柳属和柳属组成;该科广泛自然分布天大约从北纬82度至南纬52度的非洲、欧洲、亚洲、南美洲和北美洲。杨属约50种,分布于欧洲、亚洲、北美洲和非洲北缘;胡杨属约3种,间断分布于热带非洲、古地中海地区和墨西哥;原柳属约50种,广泛分布于非洲、欧洲、亚洲、南美洲和北美洲;钻天柳属约4种,局限分布于鄂霍次克海和日本海四周地  相似文献   

5.
European beech Fagus sylvatica and Norway spruce Picea abies are economically and ecologically important forest trees in large parts of Europe. Today, the beech forest reaches its northern distribution limit in south-eastern Norway and it is expected to expand northwards due to climate warming. This expansion will likely result in fundamental ecosystem changes. To increase our knowledge about the competitive balance between spruce and beech, we have investigated how beech and spruce litter affect spruce seedling emergence, growth and uptake of C and N. We did this in a seed-sowing experiment that included litter layer removal as well as reciprocal transplantations of litter layers between spruce and beech forests. Our results show that spruce seedling emergence was significantly impaired by both litter layer types, and especially so by the beech litter layer in the beech forest. The low seedling emergence in beech forests is concurrent with their lower light availability.  相似文献   

6.
近年来,正交胶合木(CLT)建筑在欧美地区得到广泛应用并向全球推广。文中从厂商分布、CLT应用、产业协同等方面对当前CLT的发展现状进行梳理,从环保意识、森林资源、政策法规和成本造价等方面对影响CLT建筑发展的主要因素进行对比,分析CLT建筑在我国发展所面临的障碍与机遇,并结合欧美地区的经验对我国CLT建筑的发展进行展望。研究发现,意识认知缺乏、市场需求不足及传统设计建造流程的改变是当前CLT建筑在我国发展推广所面临的主要障碍,但我国在CLT厂商及项目的市场基础、国产树种CLT的研发应用、政策法规的引导支持等方面正在逐步发展完善,未来将具有较大的市场空间和可行的发展路径。  相似文献   

7.
In general, trees growing at or near their limit of distribution are more sensitive to climate than those growing at their ecological core. Here we examined the growth–climate relationship of European beech (Fagus sylvatica L.) close to its northern distribution limit in southern Sweden. Tree-ring width chronologies were developed from four well-separated sites where the species was dominant (Djupeåsen, DJ; Baldringe, BLD; Komperskulla, KSK and Ryssberget Nature Reserve, RYSS). The chronologies extended from 52 years (BLD) to 150 years (RYSS). Significant negative relationships were found between tree growth and previous summer (July and August) temperatures at three sites. July temperature of the year of growth had a negative relationship with beech growth at BLD and DJ. In contrast, current summer (July and August) precipitation was positively correlated with beech growth at DJ and KSK. This sensitivity of European beech to drought at its northern limit is in line with the previous research. However, following the exceptionally dry summer in southern Sweden in 1970, a marked growth decrease was noted as well as a shift in the relationship between beech growth and current growing-season temperature. Our results show that that the radial growth of European beech has become more sensitive to drought and precipitation than temperature at its northern distribution limit in the last several decades.  相似文献   

8.
The conversion of anthropogenic into more natural, self-regenerating forests is one of the major objectives of forestry throughout Europe. In this study, we present investigations on permanent plots with different silvicultural treatment in NE German pine stands. Management of old-growth pine stands on acidic and nutrient-poor sandy sites differs in fencing, thinning, and planting of certain tree species. The investigations were carried out on the community, population, and individual level of the pine forest ecosystems. Thus, vegetation changes, size and height of tree populations, and height increment of tree individuals were observed over a time span of 6 years. Special attention was paid to short-lived tree species such as, e.g., Frangula alnus and Sorbus aucuparia, as well as to Fagus sylvatica as one of the most typical forest tree species of Central Europe. Vegetation changes are interpreted as a consequence of natural regeneration of formerly degraded forest sites, involving an increase in nutrient availability. High browsing pressure can be considered as a key factor for the inhibition of tree seedlings and growth of saplings. Some Sorbus aucuparia individuals, however, succeeded in growing out of the browsing height also in unfenced stands. Few found specimens of Fagus sylvatica proved that this species is able to establish spontaneously on these relatively dry, acidic sites under continental climate influence. Such natural regeneration processes, also including spontaneous rejuvenation of trees, can be integrated into silviculture as passive forest conversion management. An active management like thinning of stands, planting of trees, and fencing can accelerate forest conversion with regard to height growth and species number of trees.  相似文献   

9.
北半球针叶林最严重的森林病害是由广义的多年异担子菌(Heterobasidion annosum sensu lato)引起的干基白色腐朽病,但近年的研究表明多年异担子菌并不是单一的物种,目前在欧洲已分出3个独立的种,即原始多年异担子菌(Heterobasidion annosum sensu stricto)、小孔异担子菌(Heterobasidion parviporum)和冷杉异担子菌(Heterobasidi-on abietinum),它们生物学习性、形态结构,生态学,寄主范围和发生区域均有差异。应用大伏革菌Phlebiopsisgigantea对该类病害进行生物防治是较好的方法。将中国东北和西南(云南)的异担子菌单孢菌株与欧洲的三种异担子菌进行交配,结果表明中国东北和西南地区的异担子菌与原始多年异担子菌无性亲和反应,而与小孔异担子菌有性融合反应,因此中国东北和西南地区的异担子菌是小孔异担子菌,目前中国并不存在原始多年异担子菌。由于原始多年异担子菌和冷杉异担子菌均为严重的森林病原菌,应将其作为对外检疫对象。  相似文献   

10.
IntroductionItissurethatpresentelevatiollsofCO2a11dotllergrcc11-housegasesinducedbyhumanactivitiesaren1akli1gglobalclimategothroughinexperielICedcl1anges(Scl1le-subgerl987).Thecurrentquasi-equilibriulllstatesofbio-sphereecosystCm,esPeciallyterrestrialecosystems,wouldbebrokenbecausetl1estructure,fu11ction,distributio11andtlledynamicsofanyexistedecosystemsareIberesultsoflongtermadaptationofbio-systemtocurrentclin1ate.Theec()systemsdistributedinhighlatitlldeareawouldhavemuchbiggerchai1ge(Bona…  相似文献   

11.
中国环志五年来,已建环志站点45处,累计环志放飞鸟类达186种、37060只。同期回收到国内外环志鸟171只、计57种。来自7个国家和地区的环志鸟提供了候鸟跨亚洲—澳洲、亚洲—欧洲迁徙途径,以及候鸟飞越喜马拉雅山脉迁徙的证据,解释了历史上对此问题的疑点。中国的复杂生态环境和地理位置、已知候鸟迁徙于中国与各洲之间的信息、中国与亚太地区24个国家和地区相同种候鸟的分析统计情况表明:中国大陆作为东亚与北亚、南亚次大陆、澳、美、欧、南太平洋之间候鸟迁徙终端的夏候鸟繁殖地、冬候鸟越冬地以及旅鸟的停息地的国家,对于研究亚太地区候鸟迁徙规律,对于研究各国环志鸟信息的回收和繁殖生态特点、生存率及其他生态生物学信息的收集都起着重要作用。  相似文献   

12.
世界主要采脂树种及松脂生产发展趋势   总被引:10,自引:0,他引:10  
  相似文献   

13.
全球气候变暖已经成为一个不争的事实。在全球气候变化背景下,我国的气温不断增高,降水和极端天气气候事件不断增多。根据气候变化现状和趋势,文章从陆地生态系统的可能响应、北方森林的分布变化、生产力、生物地球化学循环、火干扰等方面分析了气候变化对中国北方森林生态系统的可能影响,并提出了我国北方森林应对气候变化的适应性对策。  相似文献   

14.
We measured fine root N concentration, root in vivo nitrate reductase activity (NRA) and root uptake capacity for (15)NH(4) (+) and (15)NO(3) (-) along an N-deposition gradient from northern Sweden to central Europe, encompassing a variation in N deposition rates of < 5 to about 40 kg N ha(-1) year(-1). The focus was on Picea abies (L.) Karst., but Fagus sylvatica L. in central Europe and Pinus sylvestris L. and Betula spp. in northern Sweden were also studied. We assumed that, with an increased supply of N, root N concentration would increase, activity of the inducible enzyme nitrate reductase (NR) in roots would increase, particularly with an increasing supply of NO(3) (-), and root uptake capacity for inorganic N would decline, reflecting a lower demand for N. As expected, fine root N concentration in P. abies increased along the gradient from 1.1% (d.w. basis) at the northern site to 2.1% at central European sites. This variation compared with an amplitude of 0.7-1.5% for foliage. Root in vivo NRA was low in northern Sweden, and higher in central Europe. Picea abies and broad-leaved species had similar root NRA. At one location in Denmark and one in France, however, root NRA in the spring was very high in F. sylvatica. Root uptake capacity for NO(3) (-), as measured in excised roots, was low throughout the transect, but in P. abies, it was high for NH(4) (+) in northern Sweden and decreased by a factor of 4 with increasing N deposition. A similar pattern was found in the broad-leaved species. Unless the higher availability of NO(3) (-) and lower specific root uptake capacity per unit root mass for inorganic N in central Europe (compared with northern Sweden) is balanced by a higher root biomass, the central European forests will be a weaker sink for N.  相似文献   

15.
The distribution of the double spined spruce engraver beetle Ips duplicatus ranges from Scandinavia and northeastern Europe to northern Asia. In Europe, I. duplicatus usually is associated with I. typographus on Picea abies, and due to morphological similarities and similar gallery constructions the damage and significance of I. duplicatus are often not recognised and thus underestimated. I. duplicatus has been recently reported from the southern part of Poland, the Czech Republic, Slovakia, northern parts of Austria and Germany; records are missing from many other central European countries (e.g., Hungary). The species became an important pest in some parts of central Europe, and continuous outbreaks of this bark beetle have been reported in Inner Mongolia, China, since the 1950s. The aim of this study was to compare I. duplicatus populations from Europe and Asia by genetic means using the analysis of the mitochondrial DNA. Individuals of I. duplicatus populations from China, Poland, the Czech Republic and Slovakia were collected, and 520 bp fragments of the cytochrome oxidase I (COI) gene were analysed. Four haplotypes were detected and a sequence divergence of 0.8% was found between the populations from China and Europe. These differences associate with behavioural differences in the pheromone bouquet and behavioural response of the two groups. Within Europe three haplotypes were found, but due to the small sample size no significant geographical distribution was demonstrated.  相似文献   

16.
Prediction of potential geographic distributions is important for species protection and habitat restoration.Ulmus lamellosa is an endangered and endemic species in China for which conservation efforts are required.The maximum entropy(MaxEnt) model was used to predict the current and future geographic distribution(from 2030 to 2070) of U.lamellosa in China and discuss the reasons for changes in climatic suitability.The MaxEnt model provided a good fit to our data as confirmed by an AUC value of 0.948.The suitable areas for U.lamellosa were primarily projected in the northern part of China from 2030 to2070, especially in Liaoning province.The variables"temperature seasonality", "precipitation of wettest month" and "precipitation of warmest quarter" were the most influential climatic variables in limiting the distribution of U.lamellosa.Our results clearly predict the future impacts of climate change on the geographic distribution of U.lamellosa and this can help prioritize design of localized conservation strategies in China.  相似文献   

17.
目前广东省内栽培的樱花种类品种较为单一,为筛选出适生于广东省的樱花种类,将基于19个气候因子和233个地理分布记录,利用DIVA-GIS软件结合BIOCLIM生态位模型,对大叶早樱Cerasus subhirtella、高盆樱桃C.cerasoides、山樱花C.serrulata、尾叶樱桃C.dielsiana、迎春樱桃C.discoidea和钟花樱桃C.campanulata共6种原产于我国的野生樱花在当前和未来气候下的适生区进行预测,结果显示:在粤北地区引种除高盆樱桃外的5种樱花种类会有较好表现,也可尝试在广东其他地区引种大叶早樱、山樱花、钟花樱桃等种类,且主成分分析表明年均温是6个种共同的主导气候限制因子。  相似文献   

18.
Xylem cavitation resistance is a key physiological trait correlated with species tolerance to extreme drought stresses. Little is known about the genetic variability and phenotypic plasticity of this trait in natural tree populations. Here we measured the cavitation resistance of 17 Fagus sylvatica populations representative of the full range of the species in Europe. The trees were grown in three field trials under contrasting climatic conditions. Our findings suggest that the genotypic variability of cavitation resistance is high between genotypes of a given population. By contrast, no significant differences were found for this trait across populations, the mean population cavitation resistance being remarkably constant in each trial. We found a significant site effect and a significant site?×?population interaction, suggesting that cavitation resistance has a high phenotypic plasticity and that this plasticity is under genetic control. The implications of our findings for beech forest management in a context of climate change are discussed.  相似文献   

19.
我国花境应用现状与前景分析   总被引:7,自引:0,他引:7  
花境是一种最自然优美、最具亲和力的花卉应用形式。它起源于欧洲,目前在欧美应用广泛。我国对花境的研究应用较少,但已逐步开始关注应用这种形式。针对目前我国花境研究较少、花境应用形式单一、植物材料不够丰富的现状,探讨其原因,提出在加大宣传力度的同时,特别要注意丰富花境植物种类,同时提高设计师水平。要求设计师不仅要灵活运用植物材料以及具有创造性设计的能力,还要充分运用环境心理学知识,创造精彩的花境景观,满足人们的审美要求。  相似文献   

20.
竹类植物是昭通市北部比较优势突出的生物资源。昭通市位于中国竹子分布的混合竹林带区,复杂的地形地貌、温和湿润的气候条件及多样的土壤类型,孕育了丰富的竹类资源;昭通市自然分布的竹类15属78种,是我国西南地区竹类植物富集区之一。截至2018年底,全市竹林总面积17.19万hm2,占全国竹林面积的0.28%,占全省竹林面积的21.4%,是全国竹资源富集区和云南竹资源最富集地区之一。本文系统地介绍了昭通市竹类植物资源的种类、特点及分布情况,并对其开发利用提出了建设性意见。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号