微地形对江西武夷山南方铁杉针阔混交林幼树更新的影响  

Effect of micro-topography on the saplings regeneration in the coniferous (Tsuga chinensis var. tchekiangensis) and broadleaf mixed forest in the Wuyishan, Jiangxi Province

作　　者：赵家豪 孙晓丹 叶钰倩 祝于红 雷平 陈斌 关庆伟[1,2] ZHAO Jiahao;SUN Xiaodan;YE Yuqian;ZHU Yuhong;LEI Ping;CHEN Bin;GUAN Qingwei(College of Biology and the Environment,Nanjing Forestry University,Nanjing 210037,China;Co-Innovation Center for the Sustainable Forestry in Southern China,Nanjing Forestry University,Nanjing 210037,China;Administrative Bureau of Jiangxi Wuyishan National Nature Reserve,Shangrao 334515,China)

机构地区：[1]南京林业大学生物与环境学院,南京210037 [2]南京林业大学南京现代林业创新协同中心,南京210037 [3]江西武夷山国家级自然保护区管理局,上饶334515

出　　处：《生态学报》2022年第6期2357-2367,共11页Acta Ecologica Sinica

基　　金：国家重点研发计划项目(2016YFC0502703)。

摘　　要：为探讨江西武夷山南方铁杉针阔混交林内不同微地形中幼树更新特征的差异,明晰不同微地形生境对幼树天然更新的影响。以江西武夷山国家级自然保护区内海拔约1800m的南方铁杉针阔混交原始林为研究对象,基于在其中建立的中亚热带南方铁杉针阔混交林动态监测固定样地首次调查数据,将固定样地中160个20m×20m的样方根据其海拔、凹凸度和坡度3种地形参数通过C-均值模糊聚类划分成不同的微地形生境,比较这不同微地形下的更新幼树种类组成及幼树更新特征,包括幼树密度,幼树平均胸径、平均高、平均冠幅,空间分布格局,分析不同微地形下幼树更新特征与地形因子、林分因子之间的关系。结果显示:(1)通过聚类分析,最终将固定样地的微地形生境划分成4类,分别为陡坡、凹地、凸地、缓坡。(2)4类微地形更新幼树优势种组成类似,但优势程度存在差异。闽皖八角幼树在4类微地形中的重要值皆为第一,均大于43%。建群种南方铁杉的幼树在凸地的重要值为9.09%,具有一定优势;在陡坡的重要值为0.62%,优势程度较差。(3)陡坡的更新幼树密度最高,为399株/hm^(2),高于凹地,凸地和缓坡;幼树平均胸径和平均高的大小表现为:缓坡>凸地>凹地>陡坡,幼树平均冠幅表现为凸地>缓坡>凹地>陡坡。缓坡的幼树生长情况最优,凸地次之,陡坡的幼树生长情况最差。部分幼树更新特征指标在4类不同微地形中存在显著性差异(P<0.05)。(4)更新幼树在不同微地形中的分布类型均为聚集分布,聚集强度依次为缓坡>凸地>凹地>陡坡。幼树优势种闽皖八角多数聚集于样地的右下坡区域,南方铁杉幼树偏好地势较高的地形。(5)相关分析结果表明,地形因子中仅海拔与幼树更新存在关联,4类微地形下部分林分因子与幼树更新具有显著相关性(P<0.05)。微地形对南方铁杉针阔混交林幼树的天然更新具�Based on investigation data in permanent plot of coniferous(Tsuga chinensis var. tchekiangensis) and broadleaf mixed virgin forest in the Wuyishan National Natural Reserve of Jiangxi Province, species composition and renewal characteristics of saplings in different terrains were analyzed, and the relationship between saplings renewal and terrain factors were discussed, which provided scientific basis for maintaining biodiversity of forest ecosystem and conservation of rare and relic plant of T. chinensis var. tchekiangensis. The coniferous and broadleaf mixed virgin forest at an elevation around 1800 m was set as research site. One hundred and sixty samples of 20×20 m plots were divided into different micro-topographies by fuzzy C-mean clustering analysis of three terrain factors;there are elevation, convexity and slope. Under different micro-topography habitats, we compared the species composition and regeneration characteristics of saplings, including saplings density, the average diameter at breast height(DBH), height, crown width and spatial distribution pattern of saplings. The relationship between regeneration characteristics and terrain factors and stand factors was analyzed. The results showed that:(1) through cluster analysis, the micro-topographic habitats in permanent plot were divided into four categories: steep slope, concave, ridge and gentle slope.(2) The compositions of the regeneration dominant saplings in four micro-topography types were similar, but the degrees of dominance were different. Illicium minwanense was in an absolute dominant position in these four types, and T. chinensis var. tchekiangensis saplings had certain advantages in ridge, but the degree of dominance in steep slope was poor.(3) The saplings density in steep slope was the highest, followed by concave, ridge and gentle slope. The average DBH and average height of saplings were as follows: gentle slope>ridge>concave>steep slope, and the average crown width of saplings was ridge>gentle slope>concave>steep slope, which showed s

关 键 词：南方铁杉 针阔混交林 微地形 幼树更新 空间分布 

分 类 号：S718.5[农业科学—林学]