亚热带-温带过渡区秦岭落叶阔叶林幼苗存活机制  

Seedling survival mechanism of a deciduous broad-leaved forest in the sub-tropical to temperate transition zone in the Qinling Mountains

作　　者：何念军 朱文婷 谢峰淋 李涛 党海山[2] HE Nianjun;ZHU Wenting;XIE Fenglin;LI Tao;DANG Haishan(Administration of Foping National Nature Reserve,Hanzhong,Shaanxi 723400,China;Wuhan Botanical Garden of Chinese Academy of Sciences,Wuhan 430074,China;College of Science,Tibet University,Lhasa 850000,China;Wuhan Kelain Technology Development Co.,Ltd,Wuhan 430070,China)

机构地区：[1]陕西佛坪国家级自然保护区管理局,陕西汉中723400 [2]中国科学院武汉植物园,武汉430074 [3]西藏大学理学院,拉萨850000 [4]武汉市科籁恩科技发展有限公司,武汉430074

出　　处：《西北植物学报》2024年第1期98-104,共7页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金项目(31971491,31770517);中华环境保护基金会美团外卖青山公益专项基金项目(CEPFQS202169-20)。

摘　　要：【目的】物种幼苗的存活与各种生物和非生物因素密切相关,研究关键因素对幼苗存活的影响有助于理解群落物种共存的主要作用机制。【方法】以秦岭落叶阔叶林25 hm^(2)固定样地的木本植物幼苗为对象,对11408棵幼苗的生存动态开展连续5年(2015—2019年)的监测,利用广义线性混合模型(GLMMs)在群落水平上对影响不同年龄阶段幼苗存活的主要生物与非生物因素进行分析。【结果】(1)从群落水平来看,对幼苗存活影响最大的是生物因素,幼苗存活率与同种幼苗邻体密度和同种大树邻体胸高断面积呈显著负相关,与异种幼苗邻体密度呈显著正相关,表明物种在幼苗时期受到强烈的负密度制约效应;(2)从苗龄水平上来看,除了生物因素,影响幼苗存活的主要因素还包括海拔等非生物因素,但非生物因素的影响随着苗龄增大而减小。【结论】影响幼苗存活因素是多样的,其中生物因素的影响更显著,促进秦岭大样地中幼苗共存的主要机制为负密度制约效应。[Objective]Survival of species seedlings is closely related to various biotic and abiotic factors.Exploring the key factors affecting seedling survival is helpful for the understanding of species coexistence mechanisms.[Methods]This study was focused on the survival dynamics of the woody species seedlings in a 25 hm^(2) permanent forest of a deciduous broad-leaved forest in the Qinling Mountains,and the survivals of 11408 seedlings were examined for five consecutive years(2015-2019).The generalized linear mixed models(GLMMs)were used to examine the effect of maior biotic and abiotic factors on the survival of seedlings of different ages at the community level.[Results](1)At the community level,biotic factors played a major role in seedling survival.Seedling survival was negatively correlated with conspecific seedling density and conspecific adults.It also positively correlated with interspecific seedling density.The results showed that negative density-dependence(NDD)had significant effects on seedling dynamics.(2)From the seedling age level,in addition to biological factors,abiotic factors such as altitude also affected seedling survival.The effect of abiotic factors decreased with the increase of seedling age.[Conclusion]There are many factors affecting seedling survival,among which biological factors are more significant,and the main mechanism promoting seedling coexistence is the negative density restriction effect in the Qinling Mountains.

关 键 词：幼苗存活 负密度制约 生物因素 非生物因素 

分 类 号：Q948[生物学—植物学]