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丹江口库区湿地植被的数量分类和排序 总被引:10,自引:2,他引:10
采用双向指示种分析法(TW INSPAN)和除趋势对应分析法(DCA)对丹江口库区的湿地植被进行了数量分类和排序。TW INSPAN把30个样地划分为14个群丛,论述了各群丛的群落学特征。样地的DCA排序结果反映了植物群落类型与环境因子之间的关系,表明土壤类型和生境的水分条件变化是决定丹江口库区湿地植被分布的主导因子。目前的丹江口水库滩涂植被主要由以狗牙根(Cynodon dactylon)、长刺酸模(Rum ex maritimus)、通泉草(Mazus gracilis)和稗(Echinochloa crusgalli)等为优势种的偏旱生群落类型构成。 相似文献
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长白山森林生态系统腐木生苔藓植物生态分布的DCA排序研究 总被引:11,自引:2,他引:11
应用除趋势对应分析(DCA)对长白山不同森林类型腐木生苔藓植物分布研究表明,长白山红松阔叶混交林、暗针叶林以及两者之间的过渡林林下腐木生苔藓植物组成明显不同.红松阔叶混交林以尖叶匍灯藓、毛尖羽藓、细枝青藓等为主;过渡林以尖叶匍灯藓、鞭枝疣灯藓、羽藓、腐木藓、塔藓等为主;暗针叶林的以塔藓、钩枝镰刀藓、拟垂枝藓、曲背藓、毛梳藓等为主.暗针叶林林下腐木生苔藓植物发生量最大,物种的多样性也最高.海拔高度和林冠郁闭度是影响长白山森林林下腐木生苔藓植物生态分布的主要因素. 相似文献
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天山森林生态系统中朽木生地衣植物生态分布的DCA排序 总被引:8,自引:2,他引:8
应用DCA排序方法对天山森林生态系统中朽木生地衣植物的分布格局与海拔之间的相关性进行了分析.结果表明,不同海拔高度的不同类型的森林生态系统中分布着不同种类的朽木生地衣植物.分布于海拔800 m的主要地衣种类有脱落网衣(Lecidella elabens Fr., Kgl)、柳茶渍[Lecanora saligna (Schrad.) A. Zahlbr]等.分布于海拔900~1 100 m的有 刺小孢衣[Bryoria confusa (Awas.) Bodo & Hawksw]、叉小孢衣[Bryoria furcellata (Fr.) Bodo & Hawksw]等种类.分布于海拔1 300~1 760 m的有 粗皮石蕊[Cladonia scabriuscula (Del.) Leight.]、亚鳞石蕊[Cladonia subsquamosa (Nyl.) Vain]等种类;分布于海拔1 800~2 300 m的有 黑蜈蚣衣[Phaeophyscia nigricans (Flk.) Moberg]、美丽黑蜈蚣衣[Phaeophyscia rubropulchra (Degel.) Essl.]等种类. 相似文献
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应用双向指示种分析法(TWINSPAN)和除趋势对应分析(DCA)等数量分析方法,对山西岚县皇姑梁小流域人工植物群落生态关系进行研究,将该人工植被划分为12个群丛,分别位于不同的海拔高度和坡向。分类结果很好地反映了人工植物群落类型及优势种的分布与环境因子的关系,并在DCA二维排序图上得到了较好的验证。DCA排序轴反映了群落土壤含水量、坡向、海拔高度、人工植被恢复时间和物种多样性的梯度变化,表明土壤含水量、坡向、海拔高度、物种类型及其配置模式是影响人工植物群落分布和变化的主要环境因子,不同物种配置模式对群落演替和物种多样性变化有重要影响,油松+华北落叶松.沙棘、小叶杨+油松、油松-沙棘、油松-柠条锦鸡儿等组成的乔灌混交林的物种多样性高于柠条锦鸡儿灌木纯林,并且油松+华北落叶松-沙棘混交林的物种多样性高于小叶杨+油松混交林,混交林的生态恢复效果优于纯林,并且对该小流域的生态恢复作用明显。华北落叶松适合在该小流域海拔较高的梁坡顶、半阳坡、半阴坡和阴坡生长,小叶杨适合在其海拔较低的沟底、半阳坡和半阴坡生长,而油松、沙棘、柠条锦鸡儿的生态适应性强,可在其不同海拔和坡向生长。人工植物群落的演替进程,遵循地带性植物群落演替规律。随着群落演替,野生植物不断侵入,油松、华北落叶松、小叶杨等人工林郁闭度增加,沙棘、柠条锦鸡儿等逐渐退化,油松、华北落叶松、小叶杨等出现枯枝、死株现象,这是自然稀疏的结果,亟待加强管理。 相似文献
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Abstract An inventory of the current Balearic plants occurring in mesophyllous environments, with climatic conditions similar to those in the first half of the Holocene, was compiled. The presence of these floristic elements, extending mainly into the postglacial time, has been related to pollen records of different localities in the Balearic Islands. GIS techniques have been applied in order to map the past and the present-day vegetation suitability of some of these mesophyllous species using pollen surface samples, forest inventory data and Digital Climatic Models. We integrated the information provided by field survey, pollen records and suitability mapping in order to discuss the vegetation dynamics of different habitats. We focused on the nature and the possible causes of the vegetation landscape change that occurred approximately 5000 – 6000 uncal. years BP, when Fagus, Corylus and Buxus formations were replaced by xeric-type formations with Olea dominance. 相似文献
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芦芽山亚高山草甸是在华北地区最典型的山地草甸之一,该草甸在水土保持、生态旅游资源开发和生物多样性保护等方面发挥着重要作用。应用双向指示种分析法(TWINSPAN)和除趋势对应分析(DCA)相结合的方法,对山西芦芽山亚高山草甸进行数越分类和排序,将该草甸划分为13个群丛类型,分别位于不同的海拔高度。分类结果很好地反映了植物群丛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排序轴反映了海拔、土壤湿度和坡向的梯度变化,表明海拔高度、水热条件和地形是影响植物群丛变化的主要生态因子。 相似文献
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一、自然环境大别山位于皖鄂豫三省交界处,是长江与淮河的天然分水岭,主体部分座落在安徽省境内,最高峰为霍山县白马尖,海拔1774m,地理座标为北纬31°44′,东经106°22′。大别山北坡的气候属北亚热带湿润季风气候。根据霍山气象站(31°24′N,116°20′E, 相似文献
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按生长型划分广东省车八岭国家级自然保护区山地常绿阔叶林地被植物,研究自然干扰后连续3a(2008—2010年)不同生长型地被植物的动态变化。结果表明:(1)自然干扰后地被植物优势种的变化不大;草本植物约占优势种的60%,藤本植物约占20%—30%,灌木约占10%—20%。(2)2008年各生长型地被植物的在样方中个体数分布较其它年份都更为分散且更多;2009和2010年各生长型地被植物的个体数分布模式更为相似,尤其是灌木。2008—2010年草本植物丰富度逐年增加;藤本植物逐年减少;灌木2009年最多,2008年次之,2010年最少。(3)多响应置换过程的结果显示各生长型地被植物3a间的组成和分布有极显著差异(P0.0001);从各年度的两两比较看,各生长型地被植物组成和分布的年际差异显著程度逐渐降低:其中以草本植物的年间差异最大、年间变化的指示种最多;藤本植物居中;灌木的年间差异最小、年间变化指示种也最少。指示种分析与指示种在不同组分年份中的变化情况结合起来能筛选出指示作用更强的指示种。 相似文献
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Gordon B. Bonan Samuel Levis Stephen Sitch† Mariana Vertenstein Keith W. Oleson 《Global Change Biology》2003,9(11):1543-1566
Changes in vegetation structure and biogeography due to climate change feedback to alter climate by changing fluxes of energy, moisture, and momentum between land and atmosphere. While the current class of land process models used with climate models parameterizes these fluxes in detail, these models prescribe surface vegetation and leaf area from data sets. In this paper, we describe an approach in which ecological concepts from a global vegetation dynamics model are added to the land component of a climate model to grow plants interactively. The vegetation dynamics model is the Lund–Potsdam–Jena (LPJ) dynamic global vegetation model. The land model is the National Center for Atmospheric Research (NCAR) Land Surface Model (LSM). Vegetation is defined in terms of plant functional types. Each plant functional type is represented by an individual plant with the average biomass, crown area, height, and stem diameter (trees only) of its population, by the number of individuals in the population, and by the fractional cover in the grid cell. Three time‐scales (minutes, days, and years) govern the processes. Energy fluxes, the hydrologic cycle, and carbon assimilation, core processes in LSM, occur at a 20 min time step. Instantaneous net assimilated carbon is accumulated annually to update vegetation once a year. This is carried out with the addition of establishment, resource competition, growth, mortality, and fire parameterizations from LPJ. The leaf area index is updated daily based on prevailing environmental conditions, but the maximum value depends on the annual vegetation dynamics. The coupling approach is successful. The model simulates global biogeography, net primary production, and dynamics of tundra, boreal forest, northern hardwood forest, tropical rainforest, and savanna ecosystems, which are consistent with observations. This suggests that the model can be used with a climate model to study biogeophysical feedbacks in the climate system related to vegetation dynamics. 相似文献
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草海国家级自然保护区水生植物群落的数量分类与排序分析 总被引:4,自引:0,他引:4
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
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结合DCA排序和TW IN SPAN分类结果,将辽东山区天然次生林划分为5个群落类型:花曲柳林、蒙古栎林、阔叶混交林、水曲柳林、胡桃楸林。DCA排序与TW IN SPAN分类产生了较一致的分类结果。DCA第一轴代表的环境意义为坡向。花曲柳林多分布于阳坡的中坡及中上坡,蒙古栎林多分布在中上坡。花曲柳与蒙古栎常混生在一起,随着坡位上升,花曲柳优势度下降,而蒙古栎优势度增加。阔叶混交林多位于阴坡,乔木层没有稳定和绝对优势种,多以假色槭、风桦、色木槭为优势种,但假色槭分布于乔木层第2亚层。水曲柳林多分布在中下坡。胡桃楸分布在山下部,喜潮湿生境。色木槭在辽东山区分布广泛,重要值较高,且更新良好,很可能是群落演替顶级物种。辽东山区天然次生林林下藤本植株数量多,以五味子、软枣猕猴桃、狗枣猕猴桃为主。 相似文献
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桂林岩溶石山青冈栎群落的数量分析 总被引:8,自引:0,他引:8
应用双向指示种分析(TWINSPAN)和除趋势对应分析(DCA)方法对桂林岩溶石山青冈栎群落进行数量分类与排序。通过TWINSPAN分类,将青冈栎群落60个样方划分为8个群丛类型,探讨了各群丛类型的基本特征。结果表明:DCA排序与TWINSPAN分类结果较一致,DCA排序较好地体现了各群丛类型与环境因子的相互关系,DCA第一排序轴主要反映了坡度的变化梯度;DCA排序图的对角线基本体现了坡向的变化梯度。坡度的变化是影响岩溶石山青冈栎群落物种组成与分布的重要生态因子。 相似文献
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The research deals with three scrub communities/formations in the southern Balkans, maquis, pseudomaquis and shibljak, and their changes along the main (macro)ecological gradient. We performed DCA analysis and, since the first axis correlates with climatic data, the projection of relevés on this axis was accepted as proxy for the (macro)ecological gradient, and the species turnover along this gradient was elaborated. Linear regression was used to test the turnover of life forms, chorotypes and the life strategy of species (syntaxonomical affiliation). It was found that life forms, except hemicryptophytes and nanophanerophytes, do not change significantly along the gradient change; most chorotypes change significantly; among species, life strategies (syntaxonomical affiliation), the proportion of species of deciduous and evergreen forests and scrub, as well as species of dry grassland, change significantly. The classification established three clusters, representing three formations and we tested differences among them. It was established that stenomediterranean and Eurasian species and species of perennial grasslands differentiate all three clusters and some groups only two of them. We found that discontinuous formations can be established along a continuous gradient. Communities were also classified within the present synsystematic system. 相似文献