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1.
河北小五台山国家级自然保护区森林群落与环境的关系   总被引:2,自引:0,他引:2  
植物与环境之间的关系是一个复杂的演变过程,运用数量生态学方法探讨森林群落的物种组成、种群的生态特征、不同植物群落与环境之间的关系,有助于保护该区森林群落的稳定性和生物多样性。根据148个森林群落样方数据,选用双向指示种分析(TWINSPAN)和典范对应分析(CCA)方法,对河北小五台山国家级自然保护区森林群落进行分类和排序研究。结果表明:(1)TWINSPAN将该区的森林群落分为20个类型;(2)CCA排序结果较好地反映出群落分布格局与环境梯度的关系,各个森林群落类型在前两轴分异明显,在11个环境因子中,海拔、坡位、凋落层厚度、土壤导电率、土壤温度、土壤湿度、土壤厚度和干扰程度这8个环境因子对森林群落的分布起较大的作用,影响森林群落的分布格局,形成不同的植被类型。(3)乔木层优势种的CCA二维排序图所揭示的环境梯度与群落类型的分布有很大的相似性;t值双序图阐明了海拔、凋落层厚度、土壤温度、干扰程度等环境因子对森林群落乔木层优势种有着重要影响。采用TWINSPAN分类与CCA排序的方法,较好地解释了森林群落与环境因子的关系,为小五台山地区森林生态系统的科学管理和保护提供了理论依据,研究结果也为同类地区森林生态系统研究及保护提供参考和借鉴。  相似文献   

2.
The aims of this study were to explore the environmental factors that determine the distribution of plant communities in temporary rock pools and provide a quantitative analysis of vegetation–environment relationships for five study sites on the island of Gavdos, southwest of Crete, Greece. Data from 99 rock pools were collected and analysed using Two-Way Indicator Species Analysis (TWINSPAN), Detrended Correspondence Analysis (DCA) and Canonical Correspondence Analysis (CCA) to identify the principal communities and environmental gradients that are linked to community distribution. A total of 46 species belonging to 21 families were recorded within the study area. The dominant families were Labiatae, Gramineae and Compositae while therophytes and chamaephytes were the most frequent life forms. The samples were classified into six community types using TWINSPAN, which were also corroborated by CCA analysis. The principal gradients for vegetation distribution, identified by CCA, were associated with water storage and water retention ability, as expressed by pool perimeter and water depth. Generalised Additive Models (GAMs) were employed to identify responses of four dominant rock pool species to water depth. The resulting species response curves showed niche differentiation in the cases of Callitriche pulchra and Tillaea vaillantii and revealed competition between Zannichellia pedunculata and Chara vulgaris. The use of classification in combination with ordination techniques resulted in a good discrimination between plant communities. Generalised Additive Models are a powerful tool in investigating species response curves to environmental gradients. The methodology adopted can be employed for improving baseline information on plant community ecology and distribution in Mediterranean ephemeral pools. Handling editor: S. M. Thomaz  相似文献   

3.
Quantitative surveys of the vegetation of south-east Polynesian Islands are rarely undertaken owing to time and logistical restrictions; however they are fundamental in determining the conservation status of fragile island ecosystems. The aim of the research was to document quantitatively the vegetation of Pitcairn Island by investigating whether clearly definable plant communities existed on the island, and the underlying environmental gradients influencing these communities. Initially, 10 x 10 m quadrats were taken from all areas of the island, with environmental parameters recorded for each quadrat. The vegetation was then mapped from high altitude vantage points. Two-way indicator species analysis was used to identify distinct plant communities, and canonical correspondence analysis was used to determine the underlying environmental gradients. The vegetation consists of 14 plant communities: four coastal, six forest, two fernland and two scrub communities. Large areas are covered by non-native scrub vegetation, and by monospecific Syzygium jambos (rose-apple) plantations. Less than 30 % of the island is covered by native forest, and these areas are limited to remote valleys. Fernlands also cover large areas, including both eroding areas and ridge tops. Coastal vegetation comprises rock and cliff communities with limited strand vegetation. The major environmental gradient affecting the composition of the plant communities is altitude, but anthropogenic influences also have a large effect, owing to forest clearance and introduced species. The light environment is affected by the canopy species, and determines what ground flora can develop. Identification of distinct plant communities has allowed for a system of nature reserves to be suggested, which conserve all of these plant communities and a significant proportion of the threatened plant species.  相似文献   

4.
“Mallines” are characteristic Patagonian wet meadows. The objectives of this study were to describe plant community composition in the main mallines in northern Patagonia and to determine the influence of selected environmental variables on the distribution of vegetation. Fifty-two sites were selected for vegetation surveys and measurements of water table (WT) depth, soil pH, electric conductivity (EC), and mean annual precipitation. We performed cluster analysis for vegetation classification and correspondence analysis (CA) and canonical correspondence analysis (CCA) for vegetation ordination. Plant composition was mostly related to both environmental variables and longitude and that it was not possible to disentangle the two (i.e. the vegetation was spatially structured). We defined three plant communities that differed along two main environmental gradients. The main gradient operates on a regional scale and is determined, from west to east, by a decrease in mean annual precipitation and an increase in the depth of the WT, soil pH, and EC. The secondary gradient operates on a site scale and is determined by topographic features inside the mallín and their influence on the hydrological regime (increasing moisture from the border towards the center). This second gradient allowed us to distinguish two plant communities, one of wet characteristics in the centers of the mallín, and another of mesic characteristics along the borders of the mallín.  相似文献   

5.
Patch‐size distribution and plant cover are strongly associated to arid ecosystem functioning and may be a warning signal for the onset of desertification under changes in disturbance regimes. However, the interaction between regional productivity level and human‐induced disturbance regime as drivers for vegetation structure and dynamics remain poorly studied. We studied grazing disturbance effects on plant cover and patchiness in three plant communities located along a regional productivity gradient in Patagonia (Argentina): a semi‐desert (low‐productivity community), a shrub‐grass steppe (intermediate‐productivity community) and a grass steppe (high‐productivity community). We sampled paddocks with different sheep grazing pressure (continuous disturbance gradients) in all three communities. In each paddock, the presence or absence of perennial vegetation was recorded every 10 cm along a 50 m transect. Grazing effects on vegetation structure depended on the community and its association to the regional productivity. Grazing decreased total plant cover while increasing both the frequency of small patches and the inter‐patch distance in all communities. However, the size of these effects was the greatest in the high‐productivity community. Dominant species responses to grazing explained vegetation patch‐ and inter‐patch‐size distribution patterns. As productivity decreases, dominant species showed a higher degree of grazing resistance, probably because traits of species adapted to high aridity allow them to resist herbivore disturbance. In conclusion, our findings suggest that regional productivity mediates grazing disturbance impacts on vegetation mosaic. The changes within the same range of grazing pressure have higher effects on communities found in environments with higher productivity, markedly promoting their desertification. Understanding the complex interactions between environmental aridity and human‐induced disturbances is a key aspect for maintaining patchiness structure and dynamics, which has important implications for drylands management.  相似文献   

6.
Environmental gradients are caused by gradual changes in abiotic factors, which affect species abundances and distributions, and are important for the spatial distribution of biodiversity. One prominent environmental gradient is the altitude gradient. Understanding ecological processes associated with altitude gradients may help us to understand the possible effects climate change could have on species communities. We quantified vegetation cover, species richness, species evenness, beta diversity, and spatial patterns of community structure of vascular plants along altitude gradients in a subarctic mountain tundra in northern Sweden. Vascular plant cover and plant species richness showed unimodal relationships with altitude. However, species evenness did not change with altitude, suggesting that no individual species became dominant when species richness declined. Beta diversity also showed a unimodal relationship with altitude, but only for an intermediate spatial scale of 1 km. A lack of relationships with altitude for either patch or landscape scales suggests that any altitude effects on plant spatial heterogeneity occurred on scales larger than individual patches but were not effective across the whole landscape. We observed both nested and modular patterns of community structures, but only the modular patterns corresponded with altitude. Our observations point to biotic regulations of plant communities at high altitudes, but we found both scale dependencies and inconsistent magnitude of the effects of altitude on different diversity components. We urge for further studies evaluating how different factors influence plant communities in high altitude and high latitude environments, as well as studies identifying scale and context dependencies in any such influences.  相似文献   

7.
动物与其生存环境变量之间的关系一直是生态学家们广泛关注的问题.啮齿动物作为荒漠生态系统中重要的功能群,其数量大小和生态功能对生态系统的平衡和稳定具有重要意义.生境中的植被为啮齿动物提供赖以生存的食物资源和栖息地,了解啮齿动物群落与植被特征之间的关系对于理解动物群落变动规律具有重要意义.不同植被条件下啮齿动物群落的结构不同,Hernández等(2005)研究发现北美Chihuahuan荒漠的灌木生境中啮齿动物密度高于草地生境.  相似文献   

8.
钟娇娇  陈杰  陈倩  姬柳婷  康冰 《生态学报》2019,39(1):277-285
采用多元回归树(MRT)对秦岭山地天然次生林群落进行数量分类,采用典范对应分析(CCA)进行排序,分析了秦岭山地天然次生林群落物种多样性沿海拔梯度的变化规律。结果表明:(1) 275个样方共有种子植物195种,隶属61科128属。乔、灌、草3个层次物种多样性变化沿海拔梯度的变化趋势基本一致,呈单峰模型;(2)经交叉验证认为秦岭山地天然次生林群落可分为2类,Ⅰ冬瓜杨(Populus purdomii)+陇东海棠(Malus kansuensis)+蛇莓(Duchesnea indica)群落,Ⅱ锐齿槲栎(Quercus aliena var. acuteserrata)+黄栌(Cotinus coggygria)+茜草(Rubia cordifolia)群落;(3) CCA排序结果揭示了群落生境的分布范围,反映出生态轴的排序意义,较好地反映秦岭山地天然次生林群落与环境因子的关系,其结果表明,海拔、坡向、凋落层厚度和干扰情况4个变量对该地区次生林群落的分布有较大的影响。  相似文献   

9.
小五台亚高山草甸与生境关系分析   总被引:2,自引:0,他引:2       下载免费PDF全文
该文结合野外植被调查,在获取更为详细的景观尺度生境数据基础上,探讨了小五台亚高山草甸植物群落与直接环境因子之间的定量关系。典范对应分析(CCA)的结果表明:1) 在小五台的亚高山草甸分布地段,热量、养分和水分条件构成了其生境特征差异的基本格局;2) 用效应温度和太阳直接辐射量所表征的热量因子,指示出研究区植物群落最基本的分化,说明热量条件是制约研究区草甸群落分布的最重要的因子;3) 养分状况的差异,除了说明生境条件本身的差异外,也在一定程度上指示了放牧干扰对群落分布的影响;4) 由地形等因素控制的土壤表层水分状况,则反映了草甸植物群落分布所受到的水分条件影响。  相似文献   

10.

东灵山华北落叶松人工林的分布格局及环境解释

  总被引:1,自引:0,他引:1  
应用TWINSPAN、CCA和物种多样性分析,从植物群落、植物种与环境的生态关系等方面研究了东灵山华北落叶松人工林的植被分布格局,并给予合理的环境解释。TWINSPAN分类将华北落叶松人工林分为4个类型,分类结果在CCA二维排序图上得到了较好的验证。样方与物种的CCA排序较好地揭示了该区华北落叶松人工林的分布格局与环境梯度的关系:坡位、坡度、土壤厚度和海拔是影响该区华北落叶松人工林的主导因子。结合物种多样性分析,结果表明东灵山绝大多数华北落叶松人工林生长良好,并根据华北落叶松喜凉湿习性,建议在该区自然分布海拔以下造林时,应优先选择阴坡和半阴坡的中、下位坡。  相似文献   

11.
汶川地震滑坡迹地植物群落与环境的关系   总被引:1,自引:0,他引:1  
孙丽文  史常青  李丹雄  赵廷宁 《生态学报》2016,36(21):6794-6803
为了加快汶川地震滑坡迹地人工恢复植被的进程,探讨地震诱发的滑坡迹地植物群落与环境的关系。在5·12地震重灾区北川境内选取29个样地进行植被调查,采用10个环境指标刻画植物群落的地形、空间位置和土壤养分特征;利用TWINSPAN、CCA、DCA和DCCA,分析植物种、植物群落和植物生活型与环境的关系。结果显示:1)研究区的植物群落可划分为9个类型。2)研究区环境变量对植物种的解释量为21.96%,第一排序轴与pH值、海拔、土壤质地相关,反映的是植物种从次生植物群落向原生植物群落变化。通过DCCA分析得出,环境变量对植物群落的排序解释了25.7%,第一排序轴与pH值、海拔、土壤质地的相关较强,反映植物群落按照耐旱、耐贫瘠→人工或先锋植物→未受损的植被变化;第二排序轴与土壤有机质、全氮含量、坡向的相关,反映的是植物群落从草本植物→乔灌草或者灌草植物变化。3)滑坡迹地的植物群落与未受损林地的植物群落物种存在较大差异。  相似文献   

12.
锦屏水电站植被数量分类与排序   总被引:7,自引:0,他引:7  
以锦屏梯级水电站大河湾段植被为研究对象,以河流流向为基础布置样方,将50个样方物种重要值及其环境因子进行TWINSPAN数量分类和DCA排序,结果显示:(1)由TWINSPAN数量分类将植被划分为7种类型,雅致雾水葛(Pouzolzia elegans)灌草群落为该区域的主要群落.(2)以TWINSPAN数量分类为基础的DCA二维排序图将样方分为6个生态类型,DCA 二维排序图横轴从左至右海拔高度逐渐降低;排序纵轴由下至上坡度逐渐升高.(3)以TWINSPAN数量分类在DCA排序图中有明确的分布范围和界限,DCA排序与TWINSPAN数量分类结合使用,能很好反映群落与环境因子间的生态关系.  相似文献   

13.
三峡库区澎溪河消落带植物群落分布格局及生境影响   总被引:2,自引:0,他引:2  
三峡消落带是一条特殊的水—陆交错带,其生境的特殊性及对整个三峡库区的影响逐渐成为地学、环境科学、生态学等学科的研究热点。植被是消落带各项生态功能的载体。然而,三峡水库的运行使消落带原有植被遭到破坏。通过对澎溪河消落带植物群落及其生境的实地调查,采用双向指示种法(TWINSPAN)划分植物群落类型,并结合方差分解和CCA排序法研究4类生境影响因素组14个生境影响因子与植物群落空间分布的关系,探讨生境对消落带植物群落组成、结构及多样性的影响。结果表明:(1)消落带植物群落包括5种类型:狗牙根+雀稗群落、狗尾草+狗牙根群落、黄荆群落、白茅+鬼针草群落、苔草群落;(2)CCA排序中,第1排序轴对消落带植被空间变化的累计解释量为6.83%,占生境条件总解释量的44.73%,能很好地解释消落带植物群落与生境的相互关系,植物群落类型沿排序轴呈梯度分布;(3)土壤是影响消落带植被空间分布格局的主要影响因素组,各影响因素组间交互作用明显。淹水时间、海拔、土壤含水量是植物群落空间分布的主要影响因子,解释量分别为5.3%、3.0%、2.9%;(4)4类影响因素组共解释消落带植物群落空间格局变化的14.6%,未解释部分所占比例较大,可能是由于消落带内生境条件复杂,影响其群落组成及空间分布的潜在因素较多,如各种土地利用政策、人类活动干扰及景观组成等因素也可能对消落带植物群落构成有影响。研究消落带植物空间分布及其与生境的关系,以期为科学认识消落带、保护水库环境提供依据。  相似文献   

14.
Abstract. Pattern of native vegetation, distribution of alien species and variation of environmental parameters were studied in mountain grasslands in a lithologically homogeneous Córdoba mountain range in Central Argentina. CCA showed that altitude was the most important factor determining the compositional variation of the vegetation, with soil nutrient status and stoniness as additional factors. Short‐grass communities, associated with the driest habitats on plateaus, showed higher small‐scale native species richness than wet‐turf communities in valleys and tall‐grass communities on slopes. Species richness was negatively correlated with soil parameters that indicate nutrient status and water availability. Also, there was a negative correlation between soil Ca‐ and Mg‐ content and richness. High native species richness coincided with high alien species richness. When smaller units – community types – were considered, it became evident that within short‐grass vegetation, the three most species‐rich community types contained significant numbers of alien species, while the other two did not. Even within one community type, the same quadrats that contained the highest number of native species, were also characterized by the highest numbers of alien species. Evidently, the same mechanism was responsible for high richness of both native and alien species. Alien species were distinguished by a greater proportion of annuals and prostrate stoloniferous plants, by lower palatability and by smaller proportion of zoochory. DCA ordination of quadrats on the basis of plant traits as attributes resulted in a clear distinction of three main vegetation types. Short‐grass vegetation was distinguished by a predomination of late flowering species, tall‐grass vegetation by the presence of high herbaceous plants and bushes, and wet‐turf vegetation by the presence of plants with storage organs, the lack of hairy leaves, and by a high proportion of cryptophytes. Quadrats with and without alien species were distinguished as well, indicating that the occurrence of aliens may be dependent on plant traits in a particular patch of a community.  相似文献   

15.
陕西子午岭生态因素对植物群落的影响   总被引:9,自引:1,他引:8  
李国庆  王孝安  郭华  朱志红 《生态学报》2008,28(6):2463-2463~2471
为探讨生境对植被格局分布的影响,对黄土高原马栏林区60块样地进行植被学调查的基础上,采用17个环境指标刻画植物群落的空间位置、地形和土壤特征;利用双向指示种分析(TWINSPAN)划分了该区不同演替阶段的植物群落类型;利用前向选择法(forward selection)及Monte Carlo检验对不同演替阶段植物群落物种组成影响显著(p<0.05)的环境因子进行筛选;利用去势典范对应分析(DCCA)排序方法分析不同演替阶段植物群落分布格局与环境的关系;利用偏典范对应分析(partial CCA)定量分离环境、空间及其交互作用对植被格局总体变异的影响.结果表明:(1)马栏林区的植物群落可划分为13个类型,分别属于4个不同的演替阶段;(2)对演替初期阶段群落影响显著的环境因子是土壤含盐量和碱解氮,对演替过渡阶段群落影响显著的环境因子是海拔和腐殖质厚度,对演替亚顶级阶段群落影响显著的因子是海拔、坡向、枯落物厚度、腐殖质厚度和pH值,而对演替顶级阶段群落分异影响显著的因子是海拔、坡向、pH值和速效磷;(3)不同演替阶段群落的生态学特性和分布规律与环境空间的生态梯度格局吻合较好;(4)随着演替的进行,环境因子单独对植物群落的影响越来越大,而样地位置单独作用和样地位置与环境因子的交互作用之和越来越小.  相似文献   

16.
Aim To study the altitudinal variation of ground spiders (Araneae, Gnaphosidae) of Crete, Greece, as far as species composition, species richness, activity and range of distribution are concerned. Location Altitudinal zones (0–2400 m) along the three main mountain massifs of the island of Crete. Methods Thirty‐three sampling sites were located from 0 to 2400 m a.s.l. on Crete, and sampled using pitfall traps. Material from the high‐activity period of Gnaphosidae (mid‐spring to mid‐autumn) was analysed. Sampling sites were divided into five altitudinal zones of 500 m each. Statistical analysis involved univariate statistics (anova ) and multivariate statistics, such as multidimensional scaling (MDS) and cluster analysis (UPGMA) using binomial data of species presence or absence. Results Species richness declines with altitude and follows a hump‐shaped pattern. The activity pattern of the family, as a whole, is not correlated with altitude and is highly species‐specific. In the highest zone, both species richness and activity decline dramatically. The altitudinal range of species distribution increases with altitude. On the Cretan summits live highly tolerant lowland species and isolated residents of the high mountains of Crete. Two different patterns of community structure are recorded. Main conclusions Communities of Gnaphosidae on Crete present two distinct structures following the altitudinal gradient, these being separated by a transitional zone between 1600 and 2000 m. This study supports previous results which show a hump‐shaped decline in species richness of Gnaphosidae along altitudinal gradients, leading to a peak at 400–700 m, where an optimum of environmental factors exists. This makes this zone the meeting point of the often opportunistic lowland species with the older and most permanent residents of the island. Rapoport's rule on the positive correlation of the altitudinal range of species distributions with altitude is also supported. The high activity recorded for the species that persist on the high mountains of Crete is indicative of a tolerant arachnofauna, and is considered to result from relaxation of competitive interactions with other species. This is related to a reduction in species numbers, shortening of the activity period on high mountains and the unique presence of high mountain species that thrive only there. As shown in our study, strategies to cope with altitude are species‐specific. Therefore, there cannot exist one single model to describe how animals react to the change in altitude, even under the same environmental conditions.  相似文献   

17.
中条山混沟地区森林乔木种的数量分类与环境解释   总被引:22,自引:0,他引:22       下载免费PDF全文
通过对中条山混沟地区森林植被调查资料的多元分析——TWINSPAN分类、CCA排序与环境解释,划分了该地区的植被类型,给出了植被与环境因子的定量关系。结果如下:1)40个样地可划分为青檀林(Form.Pteroceltis tatarinowii)、栾树林(Form. Koelreuteria paniculata)、槲栎林(Form. Quercus aliena)、栓皮栎林(Form. Quercus variabilis)、鹅耳枥+葛萝槭林(Form. Carpinus turczaninowii+Acer grosseri)、元宝槭+千金榆林(Form. Acer truncatum+Carpinus cordata)和辽东栎林(Form. Quercus liaotungensis)7种群落类型,体现了中条山地带性植被类型为暖温带落叶阔叶林的特点。2)群落类型的划分主要反映了CCA排序第一、二轴的环境梯度,CCA排序第一轴突出反映了海拔与土壤养分梯度,第二轴与土壤pH值、湿度指数和坡度显著相关。总体来说,海拔和土壤因子是影响混沟地区乔木物种分布分异的最主要环境因子。3)环境因子和空间因子解释了物种格局变化的46.14%,其中环境因子占30.79%,空间因子占8.48%,空间因子和环境因子交互作用解释的部分占6.87%。良好的环境解释反映了调查取样和环境因子选取的合理性,同时也体现了混沟地区植被的原始性。  相似文献   

18.
Changes in abiotic factors along altitudinal and latitudinal gradients cause powerful environmental gradients. The topography of alpine areas generates environmental gradients over short distances, and alpine areas are expected to experience greater temperature increase compared to the global average. In this study, we investigate alpha, beta, and gamma diversity, as well as community structure, of vascular plant communities along altitudinal gradients at three latitudes in the Swedish mountains. Species richness and evenness decreased with altitude, but the patterns within the altitudinal gradient varied between sites, including a sudden decrease at high altitude, a monotonic decrease, and a unimodal pattern. However, we did not observe a decline in beta diversity with altitude at all sites, and plant communities at all sites were spatially nested according to some other factors than altitude, such as the availability of water or microtopographic position. Moreover, the observed diversity patterns did not follow the latitudinal gradient. We observed a spatial modularity according to altitude, which was consistent across sites. Our results suggest strong influences of site‐specific factors on plant community composition and that such factors partly may override effects from altitudinal and latitudinal environmental variation. Spatial variation of the observed vascular plant communities appears to have been caused by a combination of processes at multiple spatial scales.  相似文献   

19.
The aim of the study was to establish and verify a predictive vegetation model for plant community distribution in the alti-Mediterranean zone of the Lefka Ori massif, western Crete. Based on previous work three variables were identified as significant determinants of plant community distribution, namely altitude, slope angle and geomorphic landform. The response of four community types against these variables was tested using classification trees analysis in order to model community type occurrence. V-fold cross-validation plots were used to determine the length of the best fitting tree. The final 9node tree selected, classified correctly 92.5% of the samples. The results were used to provide decision rules for the construction of a spatial model for each community type. The model was implemented within a Geographical Information System (GIS) to predict the distribution of each community type in the study site. The evaluation of the model in the field using an error matrix gave an overall accuracy of 71%. The user’s accuracy was higher for the Crepis–Cirsium (100%) and Telephium–Herniaria community type (66.7%) and relatively lower for the Peucedanum–Alyssum and Dianthus–Lomelosia community types (63.2% and 62.5%, respectively). Misclassification and field validation points to the need for improved geomorphological mapping and suggests the presence of transitional communities between existing community types.  相似文献   

20.
东灵山濒危植物刺五加生存群落的数量分析   总被引:2,自引:1,他引:1  
许芸  张金屯 《生态学杂志》2007,26(3):314-318
在样方调查的基础上,分别采用双向指示种分类法(TWINSPAN)、除趋势对应分析法(DCA)和典范对应分析(CCA)对东灵山地区濒危植物刺五加的生存群落进行数量分析。TWINSPAN分类将刺五加生存群落分为9类,分类结果在DCA二维排序图上得到了较好的验证,其中第一轴反映的是海拔梯度,第二轴反映了坡向、坡度的变化。刺五加多分布在位于海拔较高、光照较少的杂木林中,除在少数群落中成为灌木层的优势种外,相对分布较少。CCA排序结果与DCA的排序结果基本一致,反映出植物群落分布随环境因子梯度变化的趋势,揭示了海拔和光照是限制刺五加生长的主要环境因子。  相似文献   

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