毛乌素沙地不同林龄樟子松人工林林下植物多样性和生物量的动态变化  

Dynamics of understory plant diversity and biomass of Pinus sylvestris var.mongolica plantations with different ages in Mu Us Sandy Land

作　　者：胡尔查[1,2,3] 王铮 李梓豪 杨海峰 李卓凡 王晓江[1] 高润红 HU Ercha;WANG Zheng;LI Zihao;YANG Haifeng;LI Zhuo-fan;WANG Xiaojiang∗;GAO Runhong(Inner Mongolia Academy of Forestry Science,Hohhot 010010,China;Daqing Mountains Forest Ecosystem Research Station,Inner Mongolia,Hohhot 010010,China;College of Forestry,Inner Mongolia Agricultural University,Hohhot 010019,China)

机构地区：[1]内蒙古自治区林业科学研究院,呼和浩特010010 [2]内蒙古大青山森林生态系统国家定位观测研究站,呼和浩特010010 [3]内蒙古农业大学林学院,呼和浩特010019

出　　处：《生态学杂志》2024年第11期3246-3254,共9页Chinese Journal of Ecology

基　　金：内蒙古自治区重点研发和成果转化项目(2022YFHH0106);内蒙古自自然科学基金重点项目(2020ZD04);中央财政林业和草原科技推广示范项目(内林草改[2023]18号)资助。

摘　　要：研究人工林林下植物多样性和生物量的动态变化,对评估沙地植被恢复成效和人工林管理具有重要意义。以毛乌素沙地不同林龄(Ⅰ龄级:林龄≤10 a、Ⅱ龄级:10 a<林龄≤15 a、Ⅲ龄级:15 a<林龄≤20 a、Ⅳ龄级:林龄>20 a)樟子松人工林为研究对象,对比分析了不同林龄林下植物群落特征,并用结构方程模型路径分析解析了林分因子对林下植物群落的影响。结果表明:樟子松人工林林下灌、草植物组成共记录到20科47属57种,其中灌木3种。草本植物以菊科、禾本科、豆科和藜科植物种类较多,占总草本植物种的50%。随着林龄的增加,林下草本植物科、属、种数呈先减少后增加的规律。随着林龄的增加,林下多年生草本植物增加,一、二年生植物相对减少,偏旱生植物减少、偏中生植物增加。樟子松人工林不同林龄林下草本层Shannon多样性指数、Simpson优势度指数、Margalef丰富度指数均随着林龄的增加呈先减少后增加的规律,Pielou均匀度指数随林龄的增加而逐渐增加,但各龄级之间差异不显著(P>0.05)。结构方程模型路径分析结果显示,乔木层盖度与灌木层盖度和生物量之间存在负效应关系,乔木层盖度、灌木层盖度与林下草本层盖度、地上生物量、物种丰富度和Shannon多样性指数之间均存在正效应关系。灌木层地上生物量与林下草本盖度、地上生物量、物种丰富度和Shannon多样性指数之间存在负效应关系。综上,毛乌素沙地樟子松人工林植被恢复模式有利于林下草本植物的恢复,未来沙地植被恢复中应合理配置乔、灌木,适当调控林分密度和结构,增加盖度,以提高林下物种多样性和群落稳定性。Understanding the dynamics of understory plant diversity and biomass in plantations is of great signifi-cance for assessing the effectiveness of sandy vegetation restoration and plantation management.We analyzed the characteristics of understory communities in Pinus sylvestris var.mongolica plantations with different stand ages(Ⅰ:≤10 a,Ⅱ:10 a<age≤15 a,Ⅲ:15 a<age≤20 a,Ⅳ:age>20 a)in Mu Us Sandy Land.The impact of stand factors on understory plant communities was analyzed using structural equation modeling path analysis.A total of 57 species from 47 genera and 20 families were recorded,including 3 shrub species.Asteraceae,Gramineae,Leguminosae and Chenopodiaceae dominated herbaceous layer,accounting for 50%of the total herbaceous species.With increasing stand age,the number of families,genera and species of herbaceous layer decreased first and then increased.With increasing stand age,the perennial herbaceous plants increased,the annual and biennial plants de-creased relatively,the xerophytes decreased,and the mesophytes increased.The Shannon diversity index,Simpson dominance index and Margalef richness index of herbaceous layer decreased first and then increased with increasing stand age,and the Pielou evenness index increased with increasing stand age,but there was no significant differ-ence among different stand age classes(P>0.05).There was a negative relationship between tree layer coverage and shrub layer coverage and biomass,and a positive relationship between tree layer coverage,shrub layer coverage and understory herb layer coverage,aboveground biomass,species richness and Shannon diversity index.There was a negative correlation between aboveground biomass of shrub layer and herb coverage,aboveground biomass,spe-cies richness and Shannon diversity index.In summary,the vegetation restoration model of Pinus sylvestris var.mon-golica plantation in Mu Us Sandy Land is conducive to the restoration of understory herbaceous plants.Trees and shrubs should be rationally allocated in the future restorati

关 键 词：樟子松人工林 林下植被 物种多样性 地上生物量 毛乌素沙地 

分 类 号：S718.5[农业科学—林学]