不同空间尺度西藏色季拉山急尖长苞冷杉群落谱系结构特征  

Phylogenetic structure of Abies georgei var. smithii community at different spatial scales in Sygera Mountains of Tibet, China

作　　者：杨紫玲 田民霞 喻舞阳 罗建 郑维列[1,2] 王国严 YANG Zi-ling;TIAN Min-xia;YU Wu-yang;LUO Jian;ZHENG Wei-lie;WANG Guo-yan(Key Laboratory of Forest Ecology in Tibet Pla-teau,Ministry of Education,Linzhi 860000,Tibet,China;Research Institute of Tibet Plateau Eco-logy,Tibet Agriculture and Animal Husbandry University,Linzhi 860000,Tibet,China;National Key Station of Field Scientific Observation and Experiment,Linzhi 860000,Tibet,China;Gongbu-Jiangda County Culture and Tourism Bureau,Gongbu-Jiangda 860200,Tibet,China;College of Resource and Environment,Tibet Agriculture and Animal Husbandry University,Linzhi 860000,Tibet,China;Institute of Ecological Resources and Landscape Architecture,Chengdu University of Technology,Chengdu 610051,China).)

机构地区：[1]西藏高原森林生态教育部重点实验室,西藏林芝860000 [2]西藏农牧学院高原生态研究所,西藏林芝860000 [3]西藏林芝高山森林生态系统国家野外科学观测研究站,西藏林芝860000 [4]西藏工布江达县文化和旅游局,西藏工布江达860200 [5]西藏农牧学院资源与环境学院,西藏林芝860000 [6]成都理工大学生态资源与景观研究所,成都610051

出　　处：《应用生态学报》2020年第5期1505-1510,共6页Chinese Journal of Applied Ecology

基　　金：西藏农牧学院2016年生态学科建设项目;国家自然科学基金项目(31860123,31560153)资助。

摘　　要：基于西藏色季拉山4 hm^2亚高山暗针叶林固定样地调查数据,分析了急尖长苞冷杉群落内6个径级(1~2、2~4、4~7、7~11、11~16、>16 cm)的植物在5个空间尺度(5 m×5 m、10 m×10 m、20 m×20 m、50 m×50 m、100 m×100 m)上的谱系结构。结果表明:不同空间尺度上,该群落的净谱系亲缘关系指数(NRI)和净最近种间亲缘关系指数(NTI)值均大于零,整体上表现为谱系聚集。在小空间尺度(5 m×5 m)上,谱系结构聚集强度最大。在所有空间尺度上,群落内小径级个体表现为谱系聚集,随着径级的增大(DBH>7 cm),逐渐表现为谱系发散,且发散程度随径级增加而增大。小径级个体的谱系聚集强度随空间尺度而增大;而大径级个体(DBH>7 cm)的谱系发散程度随空间尺度增加而增大。小径级群落的生境过滤和大径级群落的竞争排斥作用可能是驱动该区域急尖长苞冷杉群落构建的主要生态学过程。We analyzed the phylogenetic structure of trees within six diameter classes(1-2, 2-4, 4-7, 7-11, 11-16, >16 cm) in quadrats with different size of 5 m×5 m,10 m×10 m, 20 m×20 m, 50 m×50 m, 100 m×100 m in a Abies georgei var. smithii community in a 4 hm^2 stem-mapping plot located in subalpine dark coniferous forest of Sygera Mountains, southeast Tibet. In various spatial scales, both net relatedness index(NRI) and nearest taxon index(NTI) of the community were larger than zero, indicating a clustered phylogenetic structure with the largest clustering intensity at small spatial scale(5 m×5 m). Community of small-size classes were phylogenetically clustering. In large-size classes(DBH>7 cm) phylogenetic over dispersion became more common, with dispersion increased with increasing tree size under all spatial scales. The intensity of phylogenetic clustering in young trees increased with increasing spatial scales, while the intensity of over dispersion in large trees(DBH>7 cm) increased with spatial scale. Our results suggested that environmental filtering in small-size trees and competitive exclusion in large-size trees might be the main ecological processes driving community assembly in this region.

关 键 词：色季拉山 亚高山暗针叶林 群落构建 谱系结构 径级 

分 类 号：Q948.1[生物学—植物学]