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1.
长白山北坡植物群落复杂性的海拔梯度变化   总被引:2,自引:0,他引:2  
应用梯度格局法在长白山北坡海拔700m-2600m的坡面上每100 m海拔设置一样地,共计20块样地,通过对同一群落各样方间的相异性测定,对各海拔植物群落的复杂性进行了分析。结果表明,以主林层乔木种的二元数据计算的结果,除亚高山岳桦林外,其它各海拔群落的样方间均表现出较高的相异性,特别是低海拔的阔叶红松林平均相异系数达0.74,明显高于其它植被类型;暗针叶林各群落间差异不大,相对而言1400 m群落样方间的相异性略高于其它群落,表现出过渡性群落树种组成的复杂性;岳桦林树种组成简单,样[(267275274344322262261355317326263366275317270337265304317340313306320324241243)-0.1(322324271340304276326326265304266376324252312375276335274306313343265304310272)]落内的相异性,虽低海拔的阔叶红松林总体上高于其它群落,但差异趋势并不像乔木种那么明显。以各草本植物与所有植物种的二元数据计算的各海拔群落内样方间的相异性,表现出非常相近的趋势,群落内样方间草本植物及所有植物种均以阔叶红松林及高山冻原差异最大,暗针叶林基本稳定于比较相近的水平。图3表1参8。  相似文献   

2.
长白山北坡植物群落间物种共有度的海拔梯度变化   总被引:2,自引:0,他引:2  
应用梯度格局法在长白山北坡海拔700-2600 m之间每100 m设置一样地,共计20块样地,应用Jaccard指数,对植物群落间物种共有度的海拔梯度变化进行了分析。不同海拔群落间的共有度,无论以哪一层次的植物种来表达,基本都以与其最相邻海拔的群落之间为最高。相邻海拔群落的不同层次物种间的共有度变化存在相似性和相异性;但如相邻海拔的两个群落属于不同植被类型,其共有度则较低。群落间物种共有度的峰值与谷点反映了植被的海拔梯度格局,且灌木种的物种更替在这些地段具有非常明显的规律。在同一海拔差群落间的共有度数值都非常接近,并均随着海拔差的增加呈明显的下降趋势,表明群落各层次物种的构成有很大的相关性。  相似文献   

3.
对野生杓兰种群适生林分进行了全面的调查,对调查数据进行计算,得到杓兰野生适生林分主要建群种种类、数量、密度、频度、盖度、高度、胸径(地径)等数量及结构特征指标,并对得到的结论进行了分析。  相似文献   

4.
长白山北坡亚高山云冷杉林植物种类的重要值   总被引:1,自引:0,他引:1  
采用典型抽样方法,对长白山北坡不同海拔高度带云冷杉林的植物种类的重要值进行了初步研究。根据主要伴生树种在各云冷杉林群落的重要值,长白山北坡的云冷杉林可分为三类,即红松云冷杉林,典型云冷杉林及岳桦云冷杉林。  相似文献   

5.
谢鞋山是雷州半岛保护最为完整的天然地貌和生态植被地区之一,保存了中国内陆唯一仅存的连片野生荔枝林,其植被类型为次生季雨林。通过对谢鞋山植被开展的实地调查,分析不同海拔样带的重要值和多样性指数,结果表明:占有绝对的优势地位的乔木分别为山脚的橄榄,重要值为71.93,山腰的荔枝为84.16,山顶的山杜英重要值为89.99;其次,灌木为粗毛野桐,重要值74.16,山腰的毛果巴豆重要值为72.81,山顶的罗伞树重要值为29.47;乔木层多样性指数H、优势度指数D、均匀度指数J等最高的为山脚,分别为2.266 8、0.860 6、0.750 6;灌木层最高的为山顶,分别为3.191 5、0.949 1、0.883 8。树种重要值和多样性指数均随着海拔梯度的变化发生明显的变化,随着海拔的升高,谢鞋山依次形成以橄榄、荔枝、山杜英为建群种,其树种多样性指数在乔木层呈现随海拔升高而降低趋势,在灌木层呈现随海拔降低而呈现先降低后上升趋势。  相似文献   

6.
采用有限空间种群增长的逻辑斯谛方程,研究天然针阔混交林建群种的种群优势度增长规律。研究结果表明,群落建群种马尾松和丝栗栲的种群优势度最大增长速度的径级范围是36~40cm 和24~28cm,此外还对该群落的演替趋势进行了分析。  相似文献   

7.
在祁连山北坡中段的大野口流域,沿海拔梯度(2 500~3 300 m)调查了青海云杉中龄林的结构,并分海拔段(每100 m)进行统计。结果表明:1)研究区森林密度较大但树木个体较小,密度、胸径、树高和冠幅直径(平均值±SD)分别为1 550±628 株·hm-2、13.9±6.2 cm、8.1±3.7 m和3.3±1.7 m。随海拔升高,密度降低、平均胸径和冠幅直径增加,平均树高呈"单峰"变化,峰值在海拔2 800~2 900 m。2)研究区森林的径级组成以小树(DBH: 5~12.5 cm)和中树(DBH: 12.5~22.5 cm)为主,树高(H)以6~12 m的树木为主。随海拔升高,林内幼树(DBH≤5 cm)比例基本稳定,小树比例略有下降,中树比例呈"单峰"变化,峰值在2 800~2 900 m,大树(DBH>22.5 cm)比例增加。H≤6 m的树木比例呈"V"字型变化,在海拔2 800~2 900 m最低,H为6~12 m和H>12 m的树木比例均呈"单峰"变化,峰值分别在海拔2 600~2 700 m和海拔2 800~2 900 m。3)林分高径比介于0.45~0.73,胸高断面积介于7.86~33.32 m2·hm-2,随海拔升高两者均呈"单峰"变化,峰值在海拔2 800~2 900 m。分析表明,随海拔升高,青海云杉林的结构呈明显变化,并在中间海拔区(海拔2 800~2 900 m)达到最优。因此,分海拔区段建立森林结构与水文过程的定量关系并进行生态水文模型的参数设置十分必要。  相似文献   

8.
对灵石山米槠林优势种不同叶龄叶绿体色素的差异以及优势种叶绿体色素沿海拔梯度的变化规律进行分析。结果表明:除少数优势种在某海拔梯度以外,不同叶龄叶绿素a、叶绿素b和叶绿素(a+b)存在显著或极显著差异,一般在中高海拔梯度差异最大,且2年生叶片含量高于1年生叶片;而不同叶龄间叶绿素a/b和类胡萝卜素的差异性表现复杂,表现了植物对环境的适应。不同优势种叶绿素[叶绿素a、叶绿素b和叶绿素(a+b)]在海拔梯度间存在显著差异,并且沿海拔梯度的变化呈现一定的规律性,米槠林优势种中有7种优势种不同叶龄叶绿素[叶绿素a、叶绿素b、叶绿素(a+b)]含量均随海拔的升高先升高,一般在A5(442m)或A6(531m)达到最大值,然后随海拔的升高逐渐降低,而叶绿素a/b随海拔升高变化趋势比较多样化。类胡萝卜素作为功能色素由于其功能比较复杂,对海拔的响应规律也不尽相同。海拔作为重要的环境因素对于植物叶绿体色素产生显著影响,不同的优势种沿海拔的变化规律存在差异,说明其对环境的适应对策不同。  相似文献   

9.
常绿阔叶林是江西省地带性植被类型。本文分析赣南建群树种有丝栗栲、南岭栲、米槠、木荷、黧蒴栲,而赣东北为甜槠、木荷、丝栗栲、石栎。利用标准地平均木的解析资料,建立林木树高、胸径、材积潜在的生长量函数。拟合结果以理查兹曲线拟合效果最好,相关系数均大于0.9。  相似文献   

10.
采用标准地法对卧龙自然保护区4个海拔梯度川滇高山栎群落水平结构进行了研究,结果表明:(1)在各个海拔梯度上物种以川滇高山栎为主,其相对密度分别为61.40、65.67、77.21和62.27;随海拔升高伴生木本植物种类逐渐减少,从11种减少到3种.(2)有随海拔升高,川滇高山栎群落物种相对频度大于2.0以上的物种数量具有先升高后降低的趋势,川滇高山栎是各个梯度出现频度最大的物种.(3)川滇高山栎群落物种重要值大于5.0以上的物种数量具有随海拔升高先升高后降低的趋势,川滇高山栎在从低到高的4个海拔梯度上重要值分别为68.47、80.37、119.93和84.01.(4)林分平均树高和林分平均地径具有随海拔升高而降低的趋势,海拔每升高100 m树高和基径分别平均降低0.18 m和0.22 cm.(5)按株频度计算,在巴朗山阳坡各个海拔梯度的川滇高山栎种群多为聚集分布;而丛频度计算,在高海拔和低海拔地带川滇高山栎种群格局呈聚集分布,在中等海拔区域川滇高山栎种群格局呈随机分布或均匀分布.  相似文献   

11.
IntroductionAs an important index reflecting species spatialpatterns, frequency reflects not only the importanceof species, but also the evenness of spatial distribution in community (Lin 1986, Magurran 1988; Dale1999). Frequency figure could reveal the complexityand diversity of community at some extent. Raunkiaer(1918) divided frequency indices into five classes,namely, Ac 1%-20%, Ba 21%-40%, Cd 41%-60%, Da61%-80%, and Ed 81%-100%, and based on 8 078frequency indices of herbaceous vegetat…  相似文献   

12.
长白山北坡土壤线虫的群落结构特征   总被引:4,自引:0,他引:4  
对长白山北坡不同海拔(7262200m)的阔叶红松林、红松云冷杉混交林、暗针叶林、岳桦林和高山苔原中土壤线虫进行了研究。在2001、2002年春天,分别在样地的枯枝落叶层、不同深度的表层土(0-5、5-10、10.20cm)掘取土壤样品进行分析。土壤线虫群落中共有27个科,60个属,其中Plectus和Tylenchus两属为优势属,优势属线虫主要分布在枯枝落叶层中。土壤线虫数量与土壤含水量显著相关(r=0.357;p〈0.01)。在不同深度和植被群落中丰富度最大的是食细菌类群线虫。土壤线虫总数和营养类群在不同土壤深度中差异显著(p〈0.05);食真菌类群/食细菌类群(F/B)和食真菌类群数量与食细菌类群数量之和与植食类群数量之比(WI)在不同深度也存在明显差异(P〈0.05)。总之,土壤水分是影响土壤线虫密度和营养组成的最主要因素之一,海拔梯度并未显著影响土壤线虫的生态指标,如营养多样性和Shannon指数。  相似文献   

13.
IntroductionAgestructureoftrees,whichreflcctsrcge11eratio11processandvelocity,meansquantityoftreesdividingbyage.Broad-leavedKoreanpineforestwastl1etypicalzol1alvegetationofChangbaiMountaininNortheastO1ina,anditwastheprimarygymnospermconununitysurvivedaftertheQuatemaryGlacierPeriod.Alotofcommunityinf`)r-mationaccumulatCdinthestr-uctllreofforeststandsa11dgrowingprocessofindividualtrees.So,athoroughstUdyonagestructureanditsdistributiol1ofbroad-leavedKore-anpine.forestwouldprovidetl1eoretical…  相似文献   

14.
From 2001 to 2003, the litter decomposition dynamics of dominant tree species were conducted using a litterbag burying method in the broadleaf-Korean pine forest, spruce-fir forest and Ermans birch forest, which represents three altitudinal belts in Changbai Mountain, northeast China. The spatial and temporal dynamics of litter decomposition and the effects of litter properties were examined. Furthermore, the decomposition trend of different species was simulated by the Olson model, and results showed that annual mass loss rates increased over time, but was not significantly correlated. Leaf decomposition rates increased after decomposing for 638 days (1.75 years), and the order of dry weight remaining rates of leaf litter for different species is: Asian white birch (Betula platyphylla) (24.56%) < Amur linden (Tilia amurensis) (24.81%) < Korean pine (Pinus koraiensis) (38.48%) < spruce (Picea jezoensis var. microsperma) (41.15%) < Ermans birch (Betula ermanii) (41.53%) < fir (Abies nephrolepis) (42.62%). The dry weight remaining rates of twig litter was smaller than that of leaf litter, and followed the order of Amur linden (44.98%) < fir (64.62%) < Korean pine (72.07%) < spruce (73.51%) < Asian white birch (77.37%) < Ermans birch (80.35%). The simulation results by the Olson model showed that, in leaf, the 95%-decomposition rates ranged from 4.5 to 8.0 years, and annual decomposition rate (k) followed the order of Amur linden (0.686) > Asian white birch (0.624) > Korean pine (0.441) > spruce (0.406) > fir (0.397) > Ermans birch (0.385); in twig, it ranged from 7.8 to 29.3 years, and k follows the order: Amur linden (0.391) > fir (0.204) > Korean pine (0.176) > spruce (0.157) > Asian white birch (0.148) > Ermans birch (0.102). In general, the differences of decomposition rate are evident between leaf and twig litter and among species, and were higher in broad-leaved species compared with coniferous species at the same elevation, and decreased with the ascending of elevation. __________ Translated from Acta Ecologica Sinica, 2006, 26(4): 1,037–1,046 [译自: 生态学报]  相似文献   

15.
Based on a vast of field investigation on stamps inTilia broad-leaved Korean pine forest on northern slope of Changbai Mountain, age structure of some major species were studied in this paper. The results showed that Korean pine population was composed of grouped patches with different ages. There were not strict intervals among the dominated generations, and the curve of age structure often had two or more peaks. The distribution of broad-leaved species in natural Korean pine forest was grouped or scattered, and age distribution was also uneven-aged. There existed close relation between quality of broad-leaved species and Korean pine. So, it shaped multi-storied and uneven-aged mixed forest. The model of age structure and growth demonstrated their passive correlation, but growth became slow when woods had reached old age. The study was funded by the Opened Research Station of Changbai Mountain Forest Ecosystems, the Chinese Academy of Sciences. (Reponsible Editor: Chai Rulhai)  相似文献   

16.
通过对2006年10月发生在长白山北坡的森林火警的分析,结果表明:人为火源是该地区引发森林火灾的重要原因,尤其是在红松籽成熟的季节;秋季人为火源多于春季。针对长白山北坡的林火隐患,提出了林火管理对策。  相似文献   

17.
长白山北坡林线分布趋势的研究   总被引:5,自引:0,他引:5  
张扬建  代力民  潘洁 《林业研究》2001,12(2):97-100
为了揭示高山树线随着气候变化而变化的现象,对长白山的高山树线变化趋势进行了研究。根据长白山北坡地区的气象数据,重点调查了(对树线有最大限制作用)一月平均气温和年积温。并在岳桦林与高山苔原之间的交叉带内测出岳桦的地径及样方内岳桦株数。根据地径与年龄有线性关系,地径可以用来代替年龄。结果表明岳桦林年龄随着海拔的上升而降低。近些年长白山北坡的气温在渐渐上升,因此导致了高山树线的上升。  相似文献   

18.
Elevational changes in patterns of diversity are important to understanding of the influence of global changes, yet few studies have addressed the distribution of microorganisms, e.g. soil micro-fungi. We studied the diversity of the forest soil micro-fungi in four vegetation belts along an elevation gradient on the north slope of Changbai Mountain in Changbai National Nature Reserve.The four belts were characterized as coniferous–deciduous mixed forest, coniferous forest, Erman's birch forest, and alpine tundra. We estimated the quantity and distribution of the fungal species in each belt and calculated three indices,viz. Shannon–Wiener diversity(H'), Pielou's evenness(J'),and Margalef's abundance(E), to depict fungal species diversity. A total of 932 strains were recorded and identified, representing 53 genera, and 108 species. Among these, Penicillium, Aspergillus, Trichoderma, Mucor, Rhizopus and Fusarium were the dominant genera. With increasing elevation, the quantity of fungi and values of H',E, and J' gradually declined.  相似文献   

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