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1.
欧洲水青冈(Fagus sylvatical L.)构筑型与形态多样性研究   总被引:14,自引:0,他引:14  
通过对植物构件和构筑型的分析,可以了解植物的整体结构与系统演化关系。高等植物构筑型的研究以树木最为深入,植物学家对全球的树木进行了构筑模式的分类,并确定了23个基本的构筑类型。植物的构筑型和其形态的多样性是密不可分的。构筑奕型确定了植物所属的整体形态类型,而对每种植物具体的形态多样性分析可以深入了解每种构筑型的数量特征及其形成过程。在概述了树木树筑型研究的基础上,系统说明了欧洲水青冈构筑才形态多样性分析的步骤和步骤和分析的意义。水青冈属(Fagus)为Troll型构筑模式,处于不同生态条件下的同一种的不同种群之间,在形态、解剖、生理和遗传多样性方面都存在着差异。树木的形态多样性虽然主要受遗传因素的控制,但生态条件对其形态和遗传多样性也有非常显著的影响。在对树木进行构筑型分析时,道德要根据构筑要素(主要是形态与生长特性)确定它所属的构筑类型,其次是分析它的形态特征与环境条件的关系,进行进一步分析其遗传多样性。  相似文献   

2.
Abstract

Areas that currently may be potentially occupied by deciduous forests represent approximately 5.5% of the Castile and Leon area. These forests include plant communities mainly dominated by Fagus sylvatica L., Quercus petraea (Mattuschka) Libl. and Betula pubescens Ehrh. subsp. celtiberica (Roth. & Vasc.) Rivas-Martínez. Taking into account the observed trends in annual mean temperature and precipitation in this region over a 37 years period (1961?–?1997), three climatic variation scenarios (for 2025, 2050 and 2075) have been proposed to determine the potential consequences of climatic change on the distribution patterns of the most representative deciduous forests. According to these scenarios, a more oceanic climate can be expected, leading to an increase in territories having a temperate climate. In this situation, deciduous forests could increase their distribution limits, thus replacing some semi-deciduous and evergreen ones. The paper also emphasizes the relevance of using bioclimatic models to anticipate possible changes in the natural vegetation of a territory. Thus, better knowledge of the seasonal distribution of temperature and rainfall under a climate change is necessary for forecasting effects on the forest distribution of a given region.  相似文献   

3.
4.
 The mechanism of freeze stress-induced embolism in Fagus sylvatica L. branches was analyzed under controlled conditions. Excised branches were exposed to successive freeze-thaw cycles in temperature controlled chambers. Thermocouples were placed on the bark to detect sap freezing exotherms. The degree of xylem embolism was estimated after each cycle by the loss of hydraulic conductivity. After one freeze-thaw cycle the degree of embolism was found to decrease with xylem specific hydraulic conductivity, small apical shoots being more susceptible to embolism. Exotherms revealed that distal shoots were freezing first and exuded sap as a result of water expansion. The lower water content in apical shoots upon freezing probably induced higher sap tensions which promoted air bubble expansion and vessel cavitation preferentially near the apices. When the decrease in water content was experimentally prevented, embolism developed to a lesser extent. The higher vulnerability of shoot apices may protect the rest of the branch from winter damage. Received: 29 May 1998 / Accepted: 15 August 1998  相似文献   

5.
全球气候变暖将严重影响中国天然橡胶种植的气候适宜区分布.根据影响中国橡胶种植的5个主导气候因子,即最冷月平均温度、极端最低温度平均值、月平均温度≥18 ℃月份、年平均气温和年平均降水量,基于最大熵MaxEnt模型,利用1981—2010年全国气候数据和RCP4.5情景的气候预估,分析了1981—2010、2041—2060、2061—2080年中国天然橡胶种植的气候适宜区变化.结果表明: 随着未来气候变化,2041—2060和2061—2080年中国天然橡胶的种植气候适宜区范围总体呈北扩趋势,对橡胶树北移有利. 2041—2060、2061—2080年中国天然橡胶气候适宜区总面积较1981—2010年呈增长趋势,高适宜区和中适宜区的面积均有增加趋势,而低适宜区面积呈减少趋势.局部区域气候适宜性发生明显变化:云南的橡胶主产区的适宜区总面积减少,其中,云南省的景洪、勐腊等地将由现在的高适宜区转变为中适宜区,海南岛及广东雷州半岛的橡胶种植高适宜区面积明显增加,在台湾岛出现了新的橡胶种植低适宜区等.  相似文献   

6.
7.
气候变化直接影响物种赖以生存的栖息地环境条件,进而影响物种的分布、数量和存活率。基于优化后最大熵(MaxEnt)模型预测气候变化下黄腹角雉(Tragopan caboti)过去、当前、未来时期的潜在栖息地格局。结果表明,降水量、温度、海拔是栖息地的主要影响因子。当前时期适宜栖息地面积较过去时期下降24.69%;未来2041—2060年间,共享社会经济路径(SSP)3-7.0与SSP5-8.5情景下黄腹角雉适宜栖息地面积较当前时期分别下降55.19%、58.10%。浙江、江西和福建是当前以及未来黄腹角雉核心适宜栖息地,适宜栖息地面积呈现下降的趋势,并往高纬度区域移动。  相似文献   

8.
Abstract

Seasonal variations of mineral nutrients and trace elements in Fagus sylvatica L. leaves at Vallombrosa (FI). - During the vegetative periodo 1987 monthly samples of beech leaves were collected in Vallombrosa forest area to determine the nutritive situation of beech trees by leaves analysis. Among nutrients, potassium appears the worst supplied one. Even copper is present in very low values, under the critical level. Heavy metals as manganese, aluminium, lead, cadmium and also iron show a clear increase during the vegetative season.  相似文献   

9.
张杰京  陈飞  谢菲  张鑫  尹文萍  樊辉 《生态学报》2023,43(9):3807-3818
生境变化直接关系到物种种群维持与人类安全,揭示其长期变化规律及其对人类的影响,可为物种保护与生境恢复提供科学支撑。但因受物种活动点数据获取与位置精度的局限,鲜见濒危、危险物种的长时序生境变化研究。以人象冲突频发的西双版纳勐海—普洱澜沧地区亚洲象种群(勐海—澜沧象群)活动区为例,提出融合MaxEnt与HSI模型的亚洲象长时序生境适宜性评价方法,即基于荟萃分析筛选出的15个亚洲象生境评价因子,结合近期有限的物种活动点监测数据,利用MaxEnt得到生境评价因子的贡献率,再运用HSI模型计算生境适宜性指数;利用该方法制作出研究区1988—2020年逐年时序的亚洲象生境适宜性图,以分析亚洲象生境的时空变化,将其与亚洲象肇事数据结合,进而分析人象冲突与生境变化的关联。结果表明:(1)基于物种生境偏好不变的前提,融合MaxEnt模型与HSI模型的生境适宜性评价方法可应用于物种的长时序生境评价,且基于亚洲象活动点数据从动物对生境利用的生态学视角定量获取亚洲象对各生境评价因子的偏好程度,使生境评价结果具有良好的生态可解释性;(2)目前亚洲象适宜生境面积占研究区面积三分之一(4039.76 km...  相似文献   

10.
Towards an understanding of the Holocene distribution of Fagus sylvatica L.   总被引:1,自引:1,他引:1  
Aim Understanding the driving forces and mechanisms of changes in past plant distribution and abundance will help assess the biological consequences of future climate change scenarios. The aim of this paper is to investigate whether modelled patterns of climate parameters 6000 years ago can account for the European distribution of Fagus sylvatica at that time. Consideration is also given to the role of non‐climatic parameters as driving forces of the Holocene spread and population expansion of F. sylvatica. Location Europe. Methods European distributions were simulated using a physiologically‐based bioclimatic model (STASH) driven by three different atmospheric general circulation model (AGCM) outputs for 6000 years ago. Results The three simulations generally showed F. sylvatica to have potentially been as widespread 6000 years ago as it is today, which gives a profound mismatch with pollen‐based reconstructions of the F. sylvatica distribution at that time. The results indicate that drier conditions during the growing season 6000 years ago could have caused a restriction of the range in the south. Poorer growth conditions with consequently reduced competitive ability were modelled for large parts of France. Main conclusions Consideration of the entire European range of F. sylvatica showed that no single driving force could account for the observed distributional limits 6000 years ago, or the pattern of spread during the Holocene. Climatic factors, particularly drought during the growing season, are the likely major determinants of the potential range. Climatic factors are regionally moderated by competition, disturbance effects and the intrinsically slow rate of population increase of F. sylvatica. Dynamic vegetation modelling is needed to account for potentially important competitive interactions and their relationship with changing climate. We identify uncertainties in the climate and pollen data, as well as the bioclimatic model, which suggest that the current study does not identify whether or not climate determined the distribution of F. sylvatica 6000 years ago. Pollen data are better suited for comparison with relative abundance gradients rather than absolute distributional limits. These uncertainties from a study of the past, where we have information about plant distribution and abundance, argue for extreme caution in making forecasts for the future using equilibrium models.  相似文献   

11.
Abstract

Fine roots represent a small proportion of total plant biomass however they represent the most dynamic component of the root systems of woody plants. There is limited information on the beech fine root production in Mediterranean ecosystems and especially in Greece. We measured live, dead and total fine root biomass (d<2 mm) (LFRB, DFRB and TFRB, respectively) over a growing season in a beech (Fagus sylvatica L.) stand on Paiko mountain, NW Greece, in order to contribute to the generally scarce knowledge of the fine root biomass of beech stands. It was found that TFRB and LFRB increased from May to July and then decreased. LFRB decreased with soil depth while there was no pattern at the change of DFRB with soil depth.  相似文献   

12.
张博鑫  李崇林  左小康  那晓东 《生态学报》2024,44(12):5194-5205
目前全球变暖趋势的加剧对丹顶鹤等大型濒危水禽的栖息地造成了严重的威胁。由于监测方法和技术手段的限制,丹顶鹤在迁徙路线上潜在生境的分布范围尚不清楚,气候变化对丹顶鹤迁徙路线生境适宜性的影响机理有待进一步研究。基于138个丹顶鹤样本分布信息和19种环境变量数据,利用 BIOMOD2 软件包构建了丹顶鹤潜在生境评价的组合模型,对丹顶鹤在亚洲东部秋季迁徙路线上的生境适宜性进行数值模拟,并预测SSP1.2-6气候背景下2021-2040年、2041-2060年、2061-2080年、2081-2100年四个不同阶段的丹顶鹤潜在生境范围的变化趋势。研究结果表明:与单模型的模拟结果相比,集成9种单模型的BIOMOD2组合模型预测精度更高。集成模型的重要性分析表明,气温日较差是丹顶鹤生境适宜性变化的最重要的影响因子。受气候变化的影响2021-2040年、2041-2060年、2061-2080年、2081-2100年丹顶鹤潜在生境的面积将分别减少到2.60×105km2、2.58×105km2、2.75×105km2、2.56×105km2,迁徙路线上胶东半岛和环渤海地区适栖生境面积减少的最为显著。本研究对于迁徙路线上珍稀水禽潜在适宜生境的模拟及全球变化背景下珍稀水禽栖息地的保育和修复具有重要意义。  相似文献   

13.
Local adaptation patterns have been found in many plants and animals, highlighting the genetic heterogeneity of species along their range of distribution. In the next decades, global warming is predicted to induce a change in the selective pressures that drive this adaptive variation, forcing a reshuffling of the underlying adaptive allele distributions. For species with low dispersion capacity and long generation time such as trees, the rapidity of the change could impede the migration of beneficial alleles and lower their capacity to track the changing environment. Identifying the main selective pressures driving the adaptive genetic variation is thus necessary when investigating species capacity to respond to global warming. In this study, we investigate the adaptive landscape of Fagus sylvatica along a gradient of populations in the French Alps. Using a double‐digest restriction‐site‐associated DNA (ddRAD) sequencing approach, we identified 7,000 SNPs from 570 individuals across 36 different sites. A redundancy analysis (RDA)‐derived method allowed us to identify several SNPs that were strongly associated with climatic gradients; moreover, we defined the primary selective gradients along the natural populations of F. sylvatica in the Alps. Strong effects of elevation and humidity, which contrast north‐western and south‐eastern site, were found and were believed to be important drivers of genetic adaptation. Finally, simulations of future genetic landscapes that used these findings allowed identifying populations at risk for F. sylvatica in the Alps, which could be helpful for future management plans.  相似文献   

14.
云南烤烟种植的气候适宜性分布将受到气候变化的深刻影响.根据云南烤烟种植气候适宜性的3个决定因子(7月平均气温、7—8月日照时数、4—9月降水量),利用1981—2060年的气候模拟数据及1986—2005年的气象台站实测数据,分析了1986—2005年及RCP 4.5和RCP8.5气候情景下2021—2040年、2041—2060年云南烤烟种植气候适宜性分布的变化.结果表明: 未来气候情景下,云南烤烟种植气候适宜分布呈现北抬东扩的趋势,未来云南烤烟可种植区域将呈逐渐增加的趋势,且2041—2060年增幅大于2021—2040年、RCP8.5情景的增幅大于RCP4.5情景,其中,烤烟的最适宜区域、次适宜区域增幅均较大,适宜区域则变化不大.未来云南中北部烟区的昆明、曲靖、大理、楚雄、丽江最适宜区面积与可种植面积增幅较大,文山、红河、普洱、西双版纳等南部烟区最适宜区面积与可种植面积减幅较大.  相似文献   

15.
We assessed the effects of irradiance received during growth on the vulnerability of Fagus sylvatica L. xylem vessels to water-stress-induced embolism. The measurements were conducted on (1) potted saplings acclimated for 2 years under 100% and 12% incident global radiation and (2) branches collected from sun-exposed and shaded sides of adult trees. Both experiments yielded similar results. Light-acclimated shoots were less vulnerable to embolism. Xylem water potential levels producing 50% loss of hydraulic conductivity were lower in sun-exposed branches and seedlings than in shade-grown ones (–3·0 versus –2·3 MPa on average). The differences in vulnerability were not correlated with differences in xylem hydraulic conductivity nor vessel diameter. Resistance to cavitation was correlated with transpiration rates, midday xylem and leaf water potentials in adult trees. We concluded that vulnerability to cavitation in Fagus sylvatica may acclimate to contrasting ambient light conditions.  相似文献   

16.
We modelled the present and future sub-Saharan winter distributions of 64 trans-Saharan migrant passerines to predict the potential impacts of climate change. These predictions used the recent ensemble modelling developments and the latest IPCC climatic simulations to account for possible methodological uncertainties. Results suggest that 37 species would face a range reduction by 2100 (16 of these by more than 50%); however, the median range size variation is −13 per cent (from −97 to +980%) under a full dispersal hypothesis. Range centroids were predicted to shift by 500±373 km. Predicted changes in range size and location were spatially structured, with species that winter in southern and eastern Africa facing larger range contractions and shifts. Predicted changes in regional species richness for these long-distance migrants are increases just south of the Sahara and on the Arabian Peninsula and major decreases in southern and eastern Africa.  相似文献   

17.
ABSTRACT

The results of a synecological and syntaxonomic study of mesophilous forest coenoses, mixed or with a prevalence of Beech, in northern Latium (Roman Tuscia), are reported. The main parameters determining the distribution pattern and floristic composition of these coenoses were altitude, exposure, acclivity, asperity and ecotope. The presence of Aquifolio-Fagetum (Doronico-Fagion) at la Tolfa and in the Sabatini Mts. is confirmed, together with the autonomy of Teucrio siculi-Quercion cerridis and Lathyro-Quercion cerridis in the Cimini-Vicani and Sabatini Mts. and on the sandstone substrates of Mt. Rufeno, respectively. Variants of Polysticho-Fagetum aceretosum pseudoplatani (Galio odorati-Fagenion) with Polystichum setiferum and with Veronica hederifolia were recognized in certain parts of the Cimini and Vicani Mts. The presence of Carpinion betuli, especially with Carpino-Coryletum avellanae and the new subassociation phyllitiaetosum scolopendrii of the latter, is recognized in gullies and ravines eroded in tufo of the Vulsino and Cimino complexes.  相似文献   

18.
Electron microscopic analysis of cotyledons of beech ( Fagus sylvatica ) at different stages of seed maturation indicates that protein bodies originate by gradual subdivision of the vacuoles in which reserve proteins are deposited. The majority of protein bodies show a proteinaceous matrix and a number of globoid inclusions of different sizes. In a small number of cells, druse-like inclusions were observed. Analysis by SDS-PAGE of proteins extracted from isolated protein bodies shows that the majority correspond to beech seed storage globulins.  相似文献   

19.
Using an enrichment procedure, we cloned microsatellite repeats from European beech (Fagus sylvatica L.) and developed primers for the amplification of microsatellite markers. Six polymorphic loci were characterized which produced 3–21 alleles in 70 individuals from one Italian population, with an observed heterozygosity between 0.58 and 0.85. All six loci amplified fragments which were polymorphic in the closely related species, Fagus orientalis, also. Owing to their very high degree of variation, these markers should be very useful in gene flow studies of these species.  相似文献   

20.
 We assessed the genetic relationships between members of the Fagaceae family by RAPDs in order to better ascertain the taxonomic status of a very particular population of Fagus sylvatica, the ‘tortuosa’ variety. Intra- and inter-population Nei and Li’s mean genetic distances were compared, and the genetic relationships between individuals were clarified on dendrograms by the Neighbor joining method. RAPD analysis was first conducted on three species from three genera, Quercus petraea, Castanea sativa, and Fagus sylvatica, in order to develop an efficient RAPD protocol. The variety level was then studied, and a general tendency of the individuals to cluster by variety was observed. Individuals also clustered by geographic locations, but the genetic distances between populations were not correlated to the distances between sites. Finally, we compared the common beech and ‘tortuosa’ varieties from two different locations, Verzy and Süntel. Both populations from one location were closer than the same variety from two sites. This last result is in agreement with those previously obtained with isozymes. Hypotheses concerning the origin of the ‘tortuosa’ variety are discussed. Received: 9 January 1998 / Accepted: 25 February 1998  相似文献   

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