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1.
甘南玛曲植物群落的多元分析与环境解释   总被引:22,自引:0,他引:22  
王孝安 《生态学报》1997,17(1):61-65
应用无偏对应分析(DCA)及二岐指示种分析(TWINSPAN)对玛曲178个植物群落样方资料进行了多斐邓和数量分类,并应用植物群落的排序值与环境参数的多元回归分析出各群类型的定量环境解释,探讨了该区植物群的基本类型生态梯度及其与环境因子的定量关系。结果表明,玛曲的植物群落类型及基分布主要取惟地热量和湿度,并可通过环境参数地数字表达式定量地确定。  相似文献   

2.
黄土高原马栏林区植物群落的多元分析与环境解释   总被引:10,自引:1,他引:9  
应用双向指示种分析(TW IN SPAN)及除趋势对应分析(DCA)对黄土高原马栏林区40个植物群落样地资料进行了多元分析——数量分类和排序,并结合群落排序值与环境参数的回归分析给出各群落类型的定量环境解释,探讨了该区植物群落的基本类型、生态梯度及其与环境因子的定量关系.结果表明:在大尺度范围内,决定马栏林区植物群落宏观分布格局的主导因子是坡向和坡位;小尺度范围内,决定该区植物群落类型和分布的主导因子是枯枝落叶层厚度、土壤腐殖质厚度、土壤全磷、速效磷含量及土壤的pH值.  相似文献   

3.
红花尔基地区沙地樟子松群落及其与环境关系研究   总被引:14,自引:1,他引:14  
通过野外调查,采用双向指示种分类(TWINSPAN)和除趋势典范对应分析(DCCA)方法。对内蒙古红花尔基地区沙地樟子松群落进行了分类和排序,并根据DCCA排序结果对樟子松群落和物种空间分布格局及其与环境因子之间关系进行定量分析。结果表明,应用TWINSPAN方法将该区沙地樟子松植被划分为6个类型。DCCA分析表明,海拔高度、地貌类型、群落盖度、土壤总碳含量、土壤总氮含量、乔木胸面积等因子对植物群落和物种分布格局影响明显。在DCCA排序图上,樟子松群落及物种的空间分布呈明显的聚集格局,可划分出不同的类群,并反映与环境因子之间具有密切的关系。对各类环境因子解释植被分布格局的作用进行了定量分解,指出地形因素是解释作用最强的变量,对未能解释部分的原因进行了分析。  相似文献   

4.
历山自然保护区猪尾沟森林群落植被格局及环境解释   总被引:49,自引:6,他引:43  
张峰  张金屯 《生态学报》2003,23(3):421-427
应用TWINSPAN、DCA和DCCA,从植物种,植物群落与环境的生态关系方面,研究历山自然保护区猪尾沟森林群落的植被分布格局,并给予合理的环境解释。结果如下:(1)采用TWINSPAN数量分类方法,将植被划分为9个群落类型。(2)对于特定的研究区域猪尾沟,制约森林群落类型,植物种分布格局的主要因素是海拔梯度,即水、热两个环境因子。(3)DCCA排序图明显反映出排序轴的生态意义,第一轴基本上突出反映了各植物群落所在环境的海拔梯度,即热量因素,沿第一轴从左到右,海拔逐渐升高,植物群落或植物种对热量要求降低;第二轴主要表现了各植物群落或植物种所在环境的坡度,坡向,即水分和光照因素,沿第二轴从下到上,坡度渐缓,坡向渐向阳。  相似文献   

5.
潘少兵  任晓冬 《生物学杂志》2010,27(5):60-63,76
在群落样方调查的基础之上,采用双向指示种分析法(TW INSPAN)和除趋势对应分析(DCA)对草海国家级自然保护区水生植物群落进行分类和排序。TW INSPAN将50个样方分为17组,根据植被分类的原则划分为17个群丛,论述了各个群丛的群落学特征。50个样方的DCA排序结果反映了植物群落类型与环境梯度之间的关系,表明影响群落分布格局的主导生态因子为水分条件,第一轴反映了各个群落类型所在的水分条件梯度。排序结果与分类结果较吻合,反映出植物群落类型和物种分布随环境因子梯度变化的趋势。  相似文献   

6.
中条山中段植物群落数量分类与排序研究   总被引:22,自引:0,他引:22  
在群落样方调查基础上,采用双向指示种分析法(TWINSPAN)和除趋势对应分析(DCA)对中条山中段植物群落进行了数量分类和排序。TWINSPAN将53个样方分为14组,根据植被分类的原则划分为14个群丛,论述了各群丛的群落学特征。53个样方的DCA排序结果反映了植物群落类型与环境梯度之间的关系,表明影响群丛分布格局的主导生态因子为海拔高度、水分和热量。DCA排序将65个种分为5个种组,各种组在排序轴上的位置反映了种组成员的生态适应性及其在群落中的重要性和更新生态位。  相似文献   

7.
卧龙自然保护区亚高山草甸的数量分类与排序   总被引:13,自引:1,他引:12  
在野外植被调查的基础上,采用植被数量分析方法对岷江流域卧龙自然保护区亚高山草甸进行TWINSPAN分类和DCA排序,研究了植物种、植物群落与环境之间的关系.结果表明,该地区亚高山草甸共有植物139种,隶属于31科88属.应用数量分类方法将114个样方分为12个群落类型.在分析不同环境因子间的关系基础上,从定量的角度揭示了影响群落分布的主要因素是海拔梯度和土壤含水量.DCA排序图反映出排序轴的生态意义,第1轴反映了各群落类型所在环境的海拔梯度,从上到下,随着海拔的升高,植物群落或植物种的耐寒性越来越强;第2轴基本上反映了各群落类型所在环境的土壤含水量.排序结果与分类结果比较吻合,反映出植物群落类型和物种分布随环境因子梯度变化的趋势.  相似文献   

8.
山西芦芽山植物群落的数量分类   总被引:12,自引:0,他引:12  
张丽霞  张峰  上官铁梁 《植物学通报》2001,18(2):231-239,176
本文在群落样方调查基础上,采用双向指示种分析法(TWINSPAN)和除趋势对应分析(DCA)对山本芦芽山植物群落进行数量分类和排序。TWINSPAN等级分类将芦芽山82个样方分为28类,可归属于7个植被型,分类结果反映了植物群落类型与环境梯度之间的关系,并在DCA二维排序图上得到较好的验证,DCA排序轴对角线基本反映了海拔,温度和湿度的梯度变化,表明群落生境所在地的海拔,温度和湿度是决定群落分布的主要因素。  相似文献   

9.
本文在群落样方调查基础上,采用双向指示种分析法(TWINSPAN)和除趋势对应分析(DCA)对山西芦芽山植物群落进行数量分类和排序。TWINSPAN等级分类将芦芽山82个样方分为28类,可归属于7个植被型,分类结果反映了植物群落类型与环境梯度之间的关系,并在 DCA二维排序图上得到较好的验证。DCA排序轴对角线基本反映了海拔、温度和湿度的梯度变化,表明群落生境所在地的海拔、温度和湿度是决定群落分布的主要因素。  相似文献   

10.
利用双向指示种(TWINSPAN)分类技术将黄河三角洲湿地草本植被划分为7个群落类型,然后应用双变量主坐标分析(double principal coordinate analysis, DPCoA)法对其进行排序,结果表明:在物种组成上,芦苇+盐地碱蓬群落为芦苇群落和盐地碱蓬+芦苇群落、盐地碱蓬群落、盐地碱蓬+补血草+碱蓬群落、补血草群落的过渡类型,而芦苇+穗状狐尾藻群落与其他群落类型差异较大;黄河三角洲湿地草本植被的分布主要与土壤因子中的土壤盐分、土壤pH等紧密相关,而与土壤全磷、全氮、有机质等养分无显著相关关系。将DPCoA和其他一些常用的植被排序方法进行了比较,相对于主分量分析(PCA)和除趋势对应分析(DCA)而言,DPCoA信息保留量更高,能够将物种组成和类别上较为接近的植物群落聚集在一起,而将差异较大的植物群落在排序图中分散开来,在揭示群落间相互关系以及植被与环境之间关系上可能更为有效。  相似文献   

11.
 根据对西藏阿里地区163个植物群落样地资料进行的多元分析——排序、数量分类与环境解释,给出了该地区植被的基本类型、生态梯度及其与环境因子的定量关系。基本分析方法包括3个步骤:1)通过无倾向对应分析(DCA)的两个排序向量揭示了阿里植被的两个主要生态梯度;2)由该梯度的二维散点图及二元指示种分析(TWINSPAN)分别产生非等级制与等级制的植物群落分类系统;3)以多元回归分析将排序值与环境及地理参数相联系而给出各类型的环境指标——定量环境解释。分析表明,阿里植被类型及其分布主要取决于热量与湿度梯度,前者可通过地理参数,后者则通过土壤特征的数学表达式来定量地确定。两梯度包含的类型、种类与生境差异颇大,由低山暖性荒漠直到高山冰缘植被,从隐带性沼泽与盐生草甸到高原地带性荒漠与草原均各得其位,各有其值。表明该数量分析法对于处理高度生态多样性的植物群落生态信息是十分有效的。  相似文献   

12.
江洪 《植物生态学报》1994,18(3):209-218
 本文应用DCA排序的方法进行了四川西北部和甘肃南部云冷杉林的梯度分析,建立了植物群落梯度环境解释的数学模型和植物群落地理分布的数学模型。研究结果表明:影响川西北甘南云冷杉林植物群落地理分布的生态梯度中最显著并起主导作用的是温度梯度和水分梯度。在水分梯度上,大致有这样的植被序列,由较湿的藓类和杜鹃冷杉及云杉林,中生性的箭竹冷杉林和云杉林,偏旱的高山栎冷杉林和云杉林;处于恢复中期的桦木林的生境也偏旱,但一般不如高山栎林。冷杉林比云杉林更趋于阴湿的生境。 在温度梯度上,呈现出灌木云杉林—桦木林—落阔冷杉林—高山栎云杉林—箭竹云杉林—箭竹红桦林—高山栎冷杉林—藓类红桦林—藓类云杉林—箭竹冷杉林—藓类云冷杉林—藓类冷杉林—小叶章云杉林—杜鹃冷杉林的排序。基本特征是:川西北和甘南的云杉林的温度需求高于冷杉林。川西北云冷杉林与甘南云冷杉林在DCA排序轴上没有明显的区别。虽然川西北地区云冷杉林的海拔分布高于甘南地区,但是其纬度也低于甘南,故在温度条件上基本一致。在水分梯度上,川西北云冷杉林的湿度要稍大于甘南云冷杉林。利用植物地理分布的数学模型和有关的图、表,详细地分析了植物群落的空间分布,进行了环境解释,并找出了主导的环境因子。  相似文献   

13.
河西走廊水生植物多样性格局、群落特征及影响因素   总被引:1,自引:0,他引:1  
水生植物是湿地生态系统重要组成部分,研究水生植物多样性分布格局及其影响因素对地区水生植物资源保护具有重要意义。通过野外调查并结合气候等环境因素,研究了河西走廊主要水生植物群落类型、数量特征、水生植物多样性分布格局及影响因素,并对中域效应假说进行了验证。研究结果表明:(1)河西走廊地区共有水生植物29科42属84种,群落的聚类分析可将河西走廊水生植物群落划分为15个主要群落类型;(2)河西走廊水生植物群落类型主要受到水温、海拔、经纬度等环境因子影响,群落物种多样性指数与盐度以及溶解性固体总量呈显著性相关;(3)河西走廊水生植物多样性空间格局呈现出"∩"型的单峰格局,中域效应模型能较好地解释该地区水生植物多样性水平的纬度格局及海拔垂直分布格局,对该区域水生植物物种丰富度在纬度和海拔梯度上的变异解释率分别为57.56%、63.5%。分析表明,河西走廊水生植物物种丰富度格局由几何(边界)限制和随机过程及其他未知因素共同控制,且几何(边界)限制和随机过程贡献率较大;同时本研究中未考虑的环境异质性、气候、人为干扰等因素也对河西走廊水生植物多样性空间分布产生重要影响。  相似文献   

14.
Aim The aim of this study was to explore the environmental factors that determine the spatial distribution of oro‐mediterranean and alti‐mediterranean plant communities in Crete. Location The paper provides a quantitative analysis of vegetation–environment relationships for two study areas within the Lefka Ori massif Crete, a proposed Natura 2000 site. Methods Eleven environmental variables were recorded: altitude, slope, aspect, percentage of bare rock, percentage of unvegetated ground, soil depth, pH, organic matter content and percentages of sand, silt and clay content. Classification of the vegetation was based on twinspan , while detrended correspondence analysis (DCA) and canonical correspondence analysis (CCA) were used to identify environmental gradients linked to community distribution. Results One hundred and twenty‐five species were recorded from 120 plots located within the two study areas. Forty‐seven of the recorded species are endemic, belonging to 35 families. Hemicryptophytes and chamaephytes were the most frequent, suggesting a typical oro‐mediterranean life form spectrum. The samples were classified into five main community types and one transitional. The main gradients, identified by CCA, were altitude and surface cover type in the North‐west site, while in the Central site the gradients were soil formation‐development and surface cover type. Main conclusions The use of classification in combination with ordination techniques resulted in a good discrimination between plant communities and a greater understanding of controlling environmental factors. The methodology adopted can be employed for improving baseline information on plant community ecology and distribution in Mediterranean mountain zones.  相似文献   

15.
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   

16.
We investigated and monitored a reed community in the fields.Data on the bio-ecologieal characteristics and β-diversity of reed communities in different environmental gradients (mainly based on water depth) of the Yellow River Delta were collected through multianalysis,extremum analysis and β-diversity index analysis.In accordance with the square sum of deviations (Ward)cluster analysis,10 sampling plots were divided into six types with the dominant plants in different plots varying according to the change in environmental gradients.The dominant plants in these plots varied from aquatic plants to xerophytes and salt tolerant plants as water depth decreased.The average height and diameter of the reeds at breast level were significantly correlated with the average water depth.The fitness curves of average density and coverage with average water depth were nonlinear.When the average water depth was 0.3 m,the average density and coverage of reeds reached the apex value,while the height and diameter of the reeds at breast level increased with the water depth.There were obvious changes to the environmental gradient in the Yellow River Delta.The transitional communities were also found to exist in the Yellow River Delta by β-diversity analysis.Vicarious species appeared with the change in water depth.The occurrence of substitute species is determined by the function of common species between adjacent belts.The different functions of common species led to differences in community structure and function and differences in dominant plants.The result reflects the variations of species present in different habitats and directly reflects environmental heterogeneity.The values of//-diversity indices of adjacent plots were higher than those of nonadjacent plots.There are transition zones between the xerophytes and aquatic plants in the Yellow River Delta.In an aquatic environment,the similarity of reed community is higher than that of xeromorphic plants.The β-diversity index can reflect plant succession trends caused by the change in environmental gradients in the Yellow River Delta.The β-diversity index reveals plant responses to changes in environmental gradient and is helpful in observing changes in patterns of species diversity in relation to environmental gradient change and evolving trends in the future,which in turn plays a prominent role when environmental water requirements of wetland are discussed.  相似文献   

17.
Abstract The vegetation patterns in the Central Coast region of New South Wales have been extensively studied with respect to single environmental variables, particularly soil nutrients. However, few data are available on the effects of multiple environmental variables. This study examines the relationships between vegetation and multiple environmental variables in natural vegetation on two underlying rock types, Hawkesbury Sandstone and Narrabeen Group shales and sandstones, in Ku-ring-gai Chase National Park, Sydney. Floristic composition and 17 environmental factors were characterized using duplicate 500 m2 quadrats from 50 sites representing a wide range of vegetation types. The patterns in vegetation and environmental factors were examined through multivariate analyses: indicator species analysis was used to provide an objective classification of plant community types, and the relationships between vegetation and environmental factors within the two soil types were examined through indirect and direct gradient analyses. Eleven plant communities were identified, which showed strong agreement with previous studies. The measured environmental factors showed strong correlations with vegetation patterns: within both soil types, the measured environmental variables explained approximately 32–35% of the variation in vegetation. No single measured environmental variable adequately described the observed gradients in vegetation; rather, vegetation gradients showed strong correlations with complex environmental gradients. These complex environmental gradients included nutrient, moisture, and soil physical and site variables. These results suggest that a simple ‘nutrient’ hypothesis regarding vegetation patterns in the Central Coast region is inadequate to explain variation in vegetation within soil types.  相似文献   

18.
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   

19.
三峡库区消涨带植物群落的数量分析   总被引:23,自引:0,他引:23  
运用双向指示种分析法(TWINSPAN)和除趋势对应分析法(DCA)对三峡库区消涨带植物群落进行了数量分类和排序分析。TWINSPAN将122个样方分成19类,可归为4个植被型,分类结果反映了植物群落与环境梯度间的关系,并在DCA分布图上得到较好的验证。DCA分布图的对角线基本反映了水淹时间长短和土壤湿度高低,表明水淹时间和土壤湿度是该区域植物群落组成和空间分布的主要限制性影响因子。对消涨带不同部位植物群落的物种组成和分布规律的分析为筛选耐水淹物种、进行三峡水库消涨带的植被恢复提供了物种参考。  相似文献   

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