三江并流地区干旱河谷植物物种多样性海拔梯度格局比较

在滇西北三江并流地区典型干旱河谷段, 在怒江、澜沧江和金沙江的东、西坡共设置了6条海拔梯度样带, 通过标准样地的植物群落调查, 分析各条样带植物的物种丰富度、物种更替率的海拔梯度格局, 并比较了地理和植被变量对分布格局的解释。干旱河谷植被带位于海拔3,000 m以下, 以灌丛和灌草丛为主, 其在各河谷的分布上限自西向东依次升高。植物物种丰富度的分布主要与海拔、流域、经纬度和植被带有关, 沿纬度和海拔梯度升高而显著增加的格局主要表现在草本层和灌木层, 灌木物种丰富度还呈现自西向东显著增加的趋势。怒江的灌木和草本种物种丰富度显著高于金沙江和澜沧江, 三条江的乔木种丰富度差异则不显著。森林带的样方草本物种丰富度显著低于灌草丛带样方, 并且还拥有后者没有的乔木种。不同样带的植物物种更替速率呈现了不一致的海拔梯度格局, 但均在样带海拔下部的灌草丛群落与海拔上部森林群落之间的交错带出现峰值。森林-灌草丛植被交错带在怒江样带处于海拔1,900-2,100 m处, 在澜沧江河谷位于海拔2,300-2,400 m, 在金沙江河谷位于海拔2,700-2,900 m。所有海拔样带的森林段或灌草丛段相对于同一样带不同植被段之间的物种更替程度为最小, 不仅小于同一流域不同样带相同植被段之间物种更替率的均值, 更小于所有样带相同植被段之间的更替率均值。在三条河流6条海拔样带的12个植被带段之间的物种更替变化中, 空间隔离因素可以解释34.2%, 而植被类型差异仅能解释不到0.5%。本研究结果显示了环境差异对不同植被类型物种丰富度的首要影响, 和各河流之间的空间隔离对植物群落构建和物种构成的主要作用。     

拉萨河谷植物群落分类与排序及物种丰富度与环境的关系

以拉萨河谷区域的植物群落为研究对象,设置30个样地、90个植物样方,运用双向指示种分析法(TWINSPAN)进行群落的分类分析,运用除趋势对应分析法(DCA)进行群落的排序分析,运用广义可加模型(GAM)进行转换后的物种丰富度(TSR)与海拔、覆盖度、纬度、经度的关系分析。TWINSPAN分类将拉萨河谷的植物群落分为8组,即落叶阔叶林、落叶阔叶灌丛、根茎苔草草甸和丛生嵩草草甸、常绿针叶灌丛草甸和落叶阔叶灌丛草甸、落叶阔叶灌丛草原、丛生禾草荒漠、落叶阔叶灌丛荒漠、小半灌木荒漠,很好地反映了群落的间断性;DCA排序的样方排序结果与TWINSPAN数量分类结果基本一致,很好地反映了群落的连续性及其生境的异质性,DCA排序结果表明,湿度是拉萨河谷植物分布的主导因素;GAM拟合模型显示,TSR沿海拔梯度的分布格局为低-高-低-高-低的双峰格局。     

秦岭牛背梁植物物种多样性垂直分布格局

基于秦岭山脉中段牛背梁自然保护区南北坡垂直样带51个样方的调查资料,利用植被数量分析方法(TWINSPAN和DCA)对牛背梁植物群落进行了分类和排序,并分析了植物物种多样性沿海拔梯度的分布格局。结果表明,牛背梁的植被群落具有明显的海拔梯度格局,从低海拔到高海拔依次分布有：锐齿槲栎(Quercus aliena var.acuteserrata)林,桦木(Betula spp.)林．巴山冷杉(Abis Jargesii)林和亚高山灌丛。海拔梯度是牛背梁山区制约植物群落分布的主要因子,而坡向和坡度则起到次要作用。对物种多样性的分析表明,物种总数、木本植物物种多样性和草本植物物种多样性在南北坡具有不同的海拔梯度格局。物种总数在南坡呈现单峰分布格局,而在北坡分布趋势不明显;木本植物物种多样性在南北坡具有相似的分布格局：在低海拔沿海拔梯度变化不明显,而在高海拔则随海拔上升而急剧下降;草本植物物种多样性在南北坡沿海拔梯度变化的规律不明显。β多样性沿海拔梯度先减少后增加,形成两端高中间低的格局,说明中海拔地区生境条件较为均一,低海拔地区的人为活动增加了生境的异质性,而高海拔地区的生态过渡特性增加了物种的更替速率以及群落的相异性。     

秦岭太白山木本植物物种多样性的梯度格局及环境解释

物种多样性沿环境梯度的分布格局是生物多样性研究的重要议题,而海拔梯度包含了各种环境因子的综合影响,因此对于探讨物种多样性沿环境梯度的分布格局具有重要意义。秦岭山脉地处我国暖温带向亚热带的过渡带,其植被垂直带和物种多样性分布格局对于研究我国南北部植被分异特征具有重要意义。基于对秦岭山脉太白山南北坡海拔1200—3750m之间的垂直样带调查的83个样方,本文利用植被数量分析方法(DCA和TWINSPAN)和Shannon-Wiener多样性指数、Pielou指数以及Jaccard相异性系数对太白山木本植物物种多样性在南北坡沿海拔梯度分布格局进行了初步研究。结果表明：太白山的木本植物群落具有明显的环境梯度格局,海拔是决定太白山植物群落分布的主要因素,而坡向起到次要作用一植物群落类型与坡向的关系不大,当考虑群落的环境梯度格局时,DCA第一轴主要与年均温密切相关,而第二轴则取决于年平均相对湿度：乔木层和灌木层的物种具有相似的海拔梯度格局,植物群落中木本植物物种丰富度和多样性随着海拔的升高单调下降;群落均匀度随着海拔变化的规律不明显;灌木层的物种多样性比乔木层更为丰富,而南坡具有比北坡更多的物种数和更高的多样性。相邻海拔之问群落的相异性在南北坡具有不同的分布格局,在北坡2800m以下,群落相异性沿海拔梯度变化不大,而在2800m以上的高海拔地区,群落相异性随海拔的升高而降低;在南坡,随着海拔的升高,群落相异性不断减少。太白山南坡群落比北坡分布更连续。     

拉萨河流域亏组山植物物种丰富度和群落特征研究

为研究草地植物群落、物种丰富度及其分布格局与影响因子之间的关系,该文以拉萨河流域林周县卡孜乡亏组山为研究地点,对山体垂直样带(3900~5100 m)植物群落特征、植物物种丰富度与各影响因子之间的关系进行了研究。研究区域共设置了13个样带(每隔100 m设一个样带),每样带设置0.5 m×0.5 m的5个样方进行植被调查,运用主成分分析(PCA)和双向指示种分析法(TWINSPAN)对植物群落进行排序和分类,运用冗余分析法(RDA)对群落及其分布格局与影响因子之间的关系进行分析,对植物物种丰富度与各因子之间的关系进行了回归分析。结果表明:该山体植物可分为3个群落类型,含7个群丛;影响区域植物群落物种组成和分布格局的主要环境因子为海拔,其次是坡度;物种丰富度与海拔、分种盖度呈单峰关系,与总盖度、坡度、地上生物量呈正相关。该研究结果为区域植物物种多样性和山地植物资源的保护和可持续利用提供了科学依据。     

三江源区高寒坡地退化植物群落多样性和地上生物量沿海拔梯度的变化特征

山地生态系统退化对生物多样性和地上生物量,以及相互关系在海拔高度梯度上的格局影响,是认识全球变化和人类干扰引起自然生态系统变化的重要内容。以青藏高原三江源区高寒坡地退化草甸和灌丛为研究对象,探讨退化草甸、灌丛群落物种多样性与地上生物量关系及其沿海拔梯度的变化规律。结果表明:(1)坡地退化的上坡位植被盖度显著大于下坡位(P＜0.05)。坡地退化高寒草甸和高寒灌丛,植物物种多样性沿海拔梯度变化规律一致,均呈现"单峰"分布格局。坡地退化高寒草甸Shannon-wiener指数和Simpson指数二次回归方程解释度达到80%和70%以上(P＜0.05)。(2)坡地退化高寒草甸和高寒灌丛的地上生物量与海拔梯度的变化规律一致,即随海拔升高高寒坡地地上生物量呈先增加后降低的变化趋势。海拔梯度对退化高寒山地地上生物量的解释度达到85%以上(P＜0.05)。(3)物种多样性和地上生物量的关系在两个坡地上表现出一致的规律,呈线性增加的变化趋势。高寒草甸坡地回归方程解释度达到70%,高寒灌丛坡地达到60%(P＜0.05)。坡地退化高寒灌丛植物群落多样性和地上生物量高于高寒草甸植物群落。高寒坡地退化草甸和灌丛植物群落物种多样性以及其与地上生物量之间的关系沿海拔梯度的变化规律一致,海拔梯度造成的环境差异对植物群落物种多样性和地上生物量影响仍较大。该研究对认识三江源区退化山地形成生态学机制,及提出有效的生态恢复措施具有重要参考价值。     

阿尔金山自然保护区植物群落生物量和物种多样性的空间格局及其影响因素

以阿尔金山国家级自然保护区的植物群落为研究对象,用样方法调查分析了不同植物群落的物种多样性、生物量的空间格局及其与环境因子间的关系。结果表明:西南高海拔地区主要植被类型为高寒草原,东北低海拔地区主要植被类型为沼泽草甸和高寒草原,西北部中海拔和东南低海拔区域的植被类型则主要为高寒荒漠;植物群落的物种多样性和生物量并未表现出明显的纬度、经度和海拔梯度变化;植物群落的多样性指数与土壤全氮、土壤总碳、土壤有机碳呈显著正相关,与土壤含水量呈极显著正相关;植物生物量与土壤有机碳和土壤含水量呈显著正相关,与土壤全氮呈极显著正相关,与土壤容重呈显著负相关。综上,阿尔金山保护区内植物群落生物多样性与生物量的空间分异是地理因子、土壤因子以及气象条件等综合作用的结果,在保护区尺度上土壤和气象因子对植物群落的影响超过地理因子的影响。     

拉萨河流域植物群落的数量分类与排序

青藏高原植物群落空间分异格局是异质生境条件下物种性状、种间相互作用等生态学过程共同作用的结果,对其分析有助于深入理解群落形成与环境因子之间的关系。基于拉萨河流域自然植被样带调查,采用双向指示种分析(TWINSPAN)和典范对应分析(CCA)等方法,探讨了群落的结构组成及影响其结构分异的主导环境因子。结果表明:(1) TWINSPAN数量分类将拉萨河流域草地系统划分成12个群系类型,即圆叶合头菊+唐古拉翠雀花群系;紫花针茅群系;青藏臺草群系;雪层杜鹃+鲜卑花-西藏嵩草群系;高山嵩草群系;小叶金露梅群系;硬叶柳+杯腺柳群系;水栒子+拱枝绣线菊-高山嵩草群系;绢毛蔷薇-冷蒿+白草群系;大果圆柏-垂穗披碱草群系;铺地柏-藏橐吾+高原荨麻群系;醉鱼草+砂生槐群系。12种群系类型包含了较多的植被类型,包括高寒灌丛草甸、高寒灌丛草原、稀树草原、高寒草甸和高寒草原等。(2) CCA排序表明:影响拉萨河流域植物群系分布的主要环境因子是年均温度、海拔和经度和纬度,其次是年均降雨量。(3) TWINSPAN分类与CCA排序结合反映了群系分布格局变异与环境因子之间的关系,可为拉萨河流域草地的保护和可持续利用,以及相关的植被群落研究提供参考。     

小秦岭森林群落数量分类、排序及多样性垂直格局

采用分层取样的方法,沿小秦岭林区海拔梯度设立56块20 m×20 m样地,用多元回归树(MRT)方法对小秦岭森林群落进行分类,采用除趋势对应分析(DCA)进行排序,用广义可加模型(GAM)研究不同生活型物种多样性沿海拔梯度分布格局。结果表明:(1)56个样地进行MRT分类,经交叉验证并依据植物群落分类和命名原则,本区植物群落可分为5类;(2)样方DCA排序明确地揭示各群落类型生境分布范围,较好地反映小秦岭自然保护区森林群落与环境因子的关系;(3)不同生活型物种多样性指数随海拔梯度变化发生一定的波动,且呈现不同的多样性格局:丰富度指数中,乔木层呈显著的单峰分布格局,灌木层在中海拔段呈明显下降趋势,草本层随着海拔的升高总体呈下降趋势;Shannon-Wiener多样性指数中,不同生活型物种随海拔变化趋势与物种丰富度变化趋势大体相同;不同生活型物种的均匀度指数随海拔变化趋势较平缓。     

香溪河流域河岸带植物群落物种丰富度格局

通过不同海拔高度的样带调查来研究香溪河流域河岸植物群落物种丰富度格局,并探讨河岸带中生物多样性维持的生态学机制。结果表明：河岸植物群落总的物种丰富度、乔木层物种丰富度和草本层物种丰富度沿海拔梯度均表现出相似的格局特征,利用抛物线方程进行拟合,物种丰富度与海拔之间有显著的相关性。灌木层物种丰富度和藤本植物物种丰富度格局特征不明显,且物种丰富度与坡度相关,在流域尺度上,海拔对物种丰富度有着重要的控制作用;在局部尺度上,季节性洪水干扰导致的空间异质性和小地形对群落的生物多样性有着重要的影响,研究结果支在于总的物种多样性在原始河流的中间河段将达到最大值的预测。     

Plant diversity patterns and their relationships with soil and climatic factors along an altitudinal gradient in the middle Tianshan Mountain area, Xinjiang, China

Patterns of plant diversity along the altitudinal gradient of Tianshan in central Xinjiang, China were examined. Plant and environment characteristics were surveyed from higher, south of Bogeda peak, to lower, north of Guerbantonggute desert. There were a total of 341 vascular plant, 295 herbage, 41 shrub, and seven tree species in the sampled plots. The plant richness of vegetation types generally showed a unimodal pattern along altitude, with a bimodal change of plant species number at 100-m intervals of altitudinal samples. The two belts of higher plant richness were in transient areas between vegetation types, the first in areas from dry grass to forest, and the second from forest to sub-alpine grass and bush. The beta diversity varied with altitudinal changes, with herbaceous species accounting for most species, and thus had similar species turnover patterns to total species. Matching the change of richness of plant species to environmental factors along altitude and correlating these by redundancy analysis revealed that the environmental factors controlling species richness and its pattern were the combined effects of temperature, precipitation, soil water, and nutrition. Water was more important at low altitude, and temperature at high altitude, and soil chemical and physical characters at middle altitudes. This study provides insights into plant diversity conservation of Bogeda Natural Reserve Areas in Tianshan Mountain. Nomenclatures: the scientific name for plants follows Flora of China (Compiling Committee of Flora of China).     

伊犁河谷北坡垂直分布格局及其与环境的关系——一种特殊的双峰分布格局

针对伊犁河谷北坡山地的植物多样性和土壤因子沿海拔的分布方式进行研究。对研究地海拔1000-2200m植物和环境特征进行调查,选取群落样地总数为44个,共调查到植物种155种,其中乔木7种、灌木18种、草本130种,调查到的群落类型完全涵盖了研究区所有沿海拔上升的群落类型。通过NLFS高级模拟显示总的物种丰富度、Simpson指数、Shannon-Wiener多样性指数、Pielou均匀度指数都与海拔呈现先升高后降低,再升高的一个特殊分布格局。出现了两个较高的物种丰富度地带,其中一个是低山荒漠到落叶阔叶林,另一个是山地草原到针叶林带。土壤养分和盐分也表现出了类似多样性的分布格局。通过PCA和相关分析表明,环境因子控制着物种丰富度和它的分布方式。水分在低海拔比较重要,在高海拔温度比较重要,而由于逆温层的作用,在较高海拔的针叶林带物种多样性出现了上升。物种丰富度与土壤总盐呈现显著负相关关系(r=-0.343),与土壤全盐也呈现显著负相关关系(r=-0.341)。Simpson指数与土壤pH值呈现显著负相关关系(r=-0.465)。Shannon-Wiener指数与土壤电导率呈现显著负相关关系(r=-0.367)。Pielou均匀度指数与土壤电导率呈现极显著负相关关系(r=-0.477),总之,多样性指数和土样盐分表现出了强相关性。这个研究为伊犁河谷植被与植物资源的保护和利用提供重要的科学依据,为河谷区山地植被与环境关系提供基础科学理论,为山地退化植被的修复提供参考案例和可借鉴的基础性数据。     

Landscape scale effects of disturbance on riparian vegetation

1. Differing responses in riparian species richness and composition to disturbance have been reported as a possible explanation for the differences along and between rivers. This paper explores the role of physical disturbance in shaping landscape‐scale patterns of species distribution in riparian vegetation along a free‐flowing river in northern Sweden. 2. To test whether sensitivity to disturbance varies across large landscapes, we experimentally disturbed riparian vegetation along an entire, free‐flowing river by scouring the soil and the vegetation turf, cutting vegetation, applying waterborne plant litter, and after a period of recovery we measured vegetation responses. The experiment was repeated for two consecutive years. 3. We found no significant effect of disturbance on species composition, but all three forms of disturbance significantly reduced species richness. There was no downstream variation in community responses to disturbance but morphological groups of species responded differently to different kinds of disturbance. Graminoids were most resistant, suppressed only by litter burial. All forms of disturbance except cutting reduced the density of herbaceous species, and species density of trees + shrubs and dwarf shrubs was negatively affected by both scouring and cutting. We also evaluated the effects of disturbance in relation to varying levels of species richness. In nearly all cases, responses were significantly negatively correlated with control plot species richness, and relative responses indicated that species‐rich plots were less resistant to scouring and cutting. 4. Our results suggest that although all disturbance treatments had an effect on species richness, variation in sensitivity to disturbance is not the most important factor shaping landscape‐scale patterns of riparian plant species richness along rivers.     

Avifaunal gradients in two arid zones of central Iran in relation to vegetation, climate, and topography

Aim To identify the ecological factors (related to vegetation, altitude, climate, or geomorphology) that could explain the main gradients of avifaunal richness and composition in arid environments of Central Iran. Location The study was carried out in two nearby semi‐arid protected areas of the Ispahan province: the Kolah‐Ghazi National Park (c. 50,000 ha; 1540–2535 m a.s.l.) and the Mouteh Wildlife Refuge (c. 220,000 ha; 1493–2900 m a.s.l.). Annual average precipitation and temperature range from 155–205 mm and 15–19.5 °C, respectively. Vegetation cover is sparse. Methods The two study areas were sampled with a 1 × 1 km grid design. A subset of 405 squares was randomly chosen and each was visited once during spring or summer by a team of five observers walking from one side of a square to the other and back, recording the birds encountered. Raptors and species considered to be accidental or migrating were not taken into account. We first looked for avifaunal, vegetation, and geomorphological gradients using Correspondence Analysis. As we found spatial autocorrelation within our response variables (avifaunal richness, abundance and/or composition), we first calculated an autocorrelation term, then added this autocorrelation term in anova , ancova (separate slope design) and stepwise regression to assess the relative role of spatial autocorrelation and environmental explanatory variables (vegetation, altitude, climate, or topography). We also partitioned the variance of the avifaunal matrix between several sets of co‐variables, after controlling for spatial effects, using a series of partial Canonical Correspondence Analyses. Results A main gradient, common to the two areas, distinguishes bird species characteristic of flat sedimentary areas and species dwelling in mountainous and/or rocky areas. Despite the generally low values of the correlations measured, we found that richness, abundance and composition of the avifauna were better correlated with topography, especially the altitudinal amplitude within each square, than any other variable, including vegetation. Altitudinal amplitude is related to substrate complexity. Main conclusions In arid zones of central Iran, topographic features seem to be the main factors structuring avifaunal composition and abundance. Avifaunal composition and richness are mainly correlated with the complexity of the substrate, but both avifaunal richness and abundance increase with altitude, probably in response to decreasing aridity. We did not observe any bird altitudinal zonation in a strict sense. These results contrast with those generally observed in mid‐latitude regions of the Palaearctic.     

Influence of altitude on the distribution pattern of flora in a protected area of Western Himalaya

IntroductionDistribution pattern and diversity of flora was compared along an altitudinal gradient using the stratified random sampling design for identifying major plant communities of Kedarnath Wildlife Sanctuary of Garhwal Himalaya, India. The reconnaissance of flora is presented, along with the analysis of the distribution of species, genera, and families within five (5) altitudinal zones. Kedarnath Wildlife Sanctuary which is situated in the Indian Himalayas harbours a rich variety of flora and fauna. The Himalayas are recognized for diverse vegetation distributed over a wide range of topographical conditions.ResultsThe analysis of diversity within five (5) altitudinal zones was carried out and a total of 324 plant species, representing 219 genera belonging to 92 families, were found. The dominant family was Asteraceae; the co-dominant family was Rosaceae, followed by Lamiaceae and Ranunculaceae. Eight (8) families were observed in all the altitudinal zones, while forty (40) families were observed in a single altitudinal zone, and the remaining forty-four (44) families were found in more than one (1) altitudinal zone. Most of the tree species were contagiously distributed, but a few of them were randomly distributed in all the altitudinal zones. The shrubs and herbs were contagiously distributed in all the altitudinal zones. The correlation analysis (P < 0.05) between altitude and number of species showed that altitude is negatively correlated with tree (r = −0.96), shrub (r = −0.61), and herb species (r = −0.20). As per the cluster analysis of tree layer, altitudinal zone - III (2450–2650 m) and altitudinal zone - IV (2900–3100 m) were found most similar. Altitudinal zone–V (3350–3550 m) was found to be dissimilar from the other zones for herbs.ConclusionsAlthough species composition varies with altitude, but there is a complex relationship between species richness and altitudinal gradient. A decreasing pattern in both species richness and family richness for trees, shrubs and herbs, was recorded with increasing altitude. The predominant factors underlying this variability in plant species and biogeography appear to be climatic and specific to each taxonomic group.     

Altitudinal effects on habitat selection of dung beetles (Scarabaeoidea: Aphodiidae) in the northern Iberian peninsula

The effects or vegetation cover on the abundance and species richness of dung beetles (Aphodiidae) were examined in three altitudinal zones: lowland (520–600 m), mid-altitude (950–963 m) and highland (1230–1275 m). Pitfall traps baited with fresh cattle dung were placed in three vegetation types at each altitudinal zone: forest, heathland and pasture. Species richness was lower in forests than in the other vegetation types. The total abundance of beetles also varied with vegetation type, but the effect was dependent on altitude. Number of individuals was higher in pasture at highlands and in heathland and forest at mid-altitude and lowlands. An altitudinal dependence of distribution of individuals between vegetation types was also found for the more abundant species in the study area. These results could be explained if the local distribution of individuals between vegetation types was determined by microcli-matic factors, mainly temperature. Differences in altitude between sites are associated with temperature changes, determining the habitat selection of species at each altitude.     

Importance of historical factors on species richness and composition of butterfly assemblages (Lepidoptera: Rhopalocera) in a northern Iberian mountain range

ABSTRACT. The butterfly assemblages of three vegetation types (pasture, heathland and rocky outcrop with Genista spp.) and two geographical orientations (a northern slope and a sheltered gorge) were studied along an altitudinal gradient in the Picos de Europa in northern Spain. In order to study the effects or historical climatic changes on current butterfly assemblages, it was examined if changes in richness and faunal composition of assemblages were joined with changes in their biogeographical composition. The three vegetation types showed characteristic butterfly assemblages, but no difference in species richness and biogeographical composition was found. Species richness in the sheltered gorge was higher than in the northern slope. Faunal composition also varied between orientations and there were more widespread and Mediterranean species in the sheltered gorge than in the northern slope. Species richness declined with increasing altitude, though a midaltitudinal peak was observed. There was a faunal segregation between high and low localities. Species richness of widespread and Mediterranean butterflies decreased as altitude increased, whereas the reverse was true for montane species. Moreover, biogeographical elements differed in their climatic tolerances measured as altitudinal ranges. Therefore, changes in richness and composition of butterfly assemblages between both slopes and along the altitudinal gradient were joined in part with variation in their biogeographical composition. These results suggest that current species richness and composition of butterfly assemblages in the Picos de Europa might be the consequence of differential colonization of refuges during the past climatic changes.     

西藏珠峰－卓奥友峰普士拉地区高山稀疏植被的群落特征及小地形的影响

在西藏定日县珠穆朗玛峰-卓奥友峰附近的普士拉地区的-山坡上(海拔5176—5390m),设置13个样方。进行群落调查、小地形测定和土壤剖面调查,分析该地区高寒植被的群落特征及其与小地形的关系。13个样方(面积25—200m^2不等)中,共记载物种80个(含变种和亚种),分别隶属于47个属。出现频度较高的种有高山嵩草(Kobresia pygmaea)、矮兔耳草(Lagottes humilis)、楔叶委陵菜(Potentilla funeata)、华马先蒿(Pedicularis oederi var.sinensis)、高山委陵菜(Potentilla polyjchista)、密生雪灵芝(Arenaria densissima)等;含物种数较多的属有：虎耳草属(Saxifraga)、风毛菊属(Saussurea)、嵩草属(Kobresia)、委陵菜属(Potentilla)、龙胆属(Gentiana)、葶苈属(Draba)等。随着海拔降低,物种和属的丰富度呈现出上升的趋势在该地区,植被盖度能较好地指示生境条件。等级聚类的结果也支持了这一观点：随着植被盖度的增加,转换物种丰富度(TSR)和转换属丰富度(TGR)增加,而物种多样性指数(Shannon-Wiener指数)减小。利用物种矩阵以及海拔、坡度、坡向、土壤深度、植被盖度等环境变量进行CCA排序,结果分出4类生境类型,它们较好地反映了群落特征与地形的关系。     

Altitudinal pattern of vegetation variation on Tenerife

Abstract. The variation in structure and floristic composition of the vegetation of Tenerife is related to different environmental factors. 200 sample plots, stratified according to altitude, exposure to wind, kind and age of parent rock, inclination and degree of disturbance were analysed throughout the island. The resulting data were analysed using univariate statistics (altitudinal distribution profiles of the more frequent species) and multivariate methods (Correspondence, Cluster and Pattern Analysis). Altitude, exposure to wind and, to a lesser extent, disturbance were found to be the major determinants of vegetational variation, whereas parent rock and inclination were less important. Ordination results show a continuum in structural and floristic variation of the vegetation with species distributions varying continually along the altitudinal gradient. Nevertheless, altitudinally bound plant community types were recognized with Cluster Analysis. Vegetational discontinuities, which were also detected by pattern analysis, are more evident on the windward slope of the island; they have been attributed to the existence of a major underlying environmental discontinuity the ‘cloud sea’-which is associated with a climatic inversion. On the leeward slope, beyond the influence of the cloud sea, discontinuities are less evident and vegetational variation seems to be closer to a coenocline, i.e. a vegetational continuum.