摘要
【目的】对比分析黄土高原南部桥山林区3种林分类型麻栎群落的种群结构与幼苗生长过程,阐明麻栎种群在不同群落类型下的数量和结构动态,为该地区麻栎林科学经营和恢复提供依据。【方法】采用样地调查法,调查12块样地(麻栎阔叶混交林、麻栎油松混交林和麻栎纯林3种林分类型,每种林分类型设置4块样地)内所有胸径大于4 cm个体的胸径(幼苗地径)、树高和冠幅等特征;在每块样地采集幼苗或幼树标准株,测定各器官生物量。以径级结构和高度级结构代替年龄结构,编制不同林分类型麻栎种群静态生命表,根据各径级麻栎种群存活量绘制存活曲线,并分析3种林分类型中1~10年生麻栎实生幼苗的高度、基径、冠幅及生物量分配差异。【结果】3种林分类型麻栎种群均呈现出随年龄增加个体数减小趋势,低龄级个体具有绝对数量优势,桥山地区麻栎种群年龄结构呈进展型。种群静态生命表表明,麻栎种群存活量随年龄增加呈降低趋势,低龄级死亡最高,为生活史脆弱期;Ⅲ、Ⅳ龄级期望寿命最高;在Ⅲ~Ⅶ龄级,麻栎阔叶混交林和麻栎油松混交林中的麻栎种群死亡率远远低于麻栎纯林。不同林分类型麻栎种群的存活曲线皆呈Deevey-Ⅲ型。实生苗基径在1~5年表现为麻栎纯林>混交林,随着年龄增加,麻栎油松混交林实生苗基径略高于其他2种林分类型,但3种林分类型间差异不显著;实生苗冠幅在2~10年表现为混交林>纯林,且3种林分类型间实生苗冠幅差异在4年后开始显著(P<0.05);麻栎油松混交林实生苗高度在2~10年均高于其他2种林分类型,3种林分类型间实生苗高度差异在5年后开始显著(P<0.05)。不同林分类型麻栎实生苗叶、干、根、侧枝生物量均随年龄增加而增长。3种林分类型间,实生苗叶生物量在1~6年差异不显著,干生物量在1~4年无显著性差异,侧枝生物量在1~2年差异不显�
【Objective】By comparing population structure and seedling growth of Quercus acutissima among three different community types,the purpose of the study was to illustrate the quantitative and structural dynamics of Q.acutissima populations,in order to provide a basis for forest restoration and management in Qiaoshan forest region,southern Loess Plateau,China.【Method】Field survey was conducted in 12 fixed plots(3 different stand types×4 reduplicates).All Q.acutissima individuals(DBH>4 cm)were measured for DBH(ground diameter for seedlings),height and crown width.Biomass of different organs was also measured for typical seedlings sampled from each plot.By substituting diameter class for age class,the static life table and survival curve were draw according to the survival amount of Q.acutissima in each diameter class.Differences among growth characteristics(height,ground diameter,crown width,and biomass allocation)of 1-10 years seedlings in three community types were analyzed.【Result】The number of individuals tended to decrease with age in all of the three stand types of Q.acutissima,i.e.the low age classes displayed an absolute advantage in number of trees,indicating that the Q.acutissima population is progressive in Qiaoshan region.The static life table of the Q.acutissima population showed that the highest mortality rate occurred at younger diameter class indicating the phase was the most vulnerable stage in life history of Q.acutissima.The life expectancy was the highest in age classes ofⅠandⅡ.The mortality of Q.acutissima between age classes ofⅢtoⅣis far lower in mixed forest of Q.acutissima with broad leaved tree and mixed forest of Q.acutissima with Pinus tabulaeformis than that in pure forest of Q.acutissima.The survival curve of the different Q.acutissima populations was Deevey-Ⅲtype.The ground diameter of seedlings for 1-5 years were larger in the pure forest than in the mixed forest,with the increase of age,the ground diameter of seedlings in Q.acutissima with P.tabulaeformis forest w
作者
张维伟
赵忠
刘金良
邓平
Zhang Weiwei;Zhao Zhong;Liu Jinliang;Deng Ping(College of Forestry,Northwest Agriculture and Forestry University Key Comprehensive Laboratory of Forestry,Shaanxi Province Key Laboratory of Silviculture on the Loess Plateau,National Forestry and Grassland Administration,Yangling 712100)
出处
《林业科学》
EI
CAS
CSCD
北大核心
2021年第7期1-10,共10页
Scientia Silvae Sinicae
基金
国家自然科学基金项目(2017YFC0504605)。
关键词
麻栎
种群结构
生境
生长特性
生物量
Quercus acutissima
population structure
habitat
growth characteristics
biomass
