雷州半岛不同林龄尾巨桉人工林根系特征及乔木层生物量分配  

Root Characteristics and Biomass Allocation of Eucalyptus urophylla × E. grandis Plantations of Different Ages in Leizhou Peninsula

作　　者：张学德 伍勇 黄宇超 黄胜 张明思 苏寒 颜炳辉 王志超 ZHANG Xuede;WU Yong;HUANG Yuchao;HUANG Sheng;ZHANG Mingsi;SU Han;YAN Binghui;WANG Zhichao(Guangxi State-owned Qipo Forest Farm,Nanning 530225,Guangxi,China;China Eucalypt Research Centre,Zhanjiang 524022,Guangdong,China;Guangdong Zhanjiang Eucalyptus Forest Ecosystem National Positioning Observation and Research Station,Zhanjiang 524022,Guangdong,China)

机构地区：[1]广西壮族自治区国有七坡林场,广西南宁530225 [2]国家林业和草原局桉树研究开发中心,广东湛江524022 [3]广东湛江桉树林生态系统国家定位观测研究站,广东湛江524022

出　　处：《桉树科技》2019年第3期22-27,共6页Eucalypt Science & Technology

基　　金：广西科技重大专项(桂科AA17204087-9);国家重点研发计划课题(2016YFD0600505,2016YFD0600504);广东湛江桉树林生态系统国家定位观测研究站运行项目(2019132141)

摘　　要：针对桉树人工林生物量估算难度大、精度低的问题,本文通过研究不同林龄尾巨桉人工林的根系生物量特征、地上部分各器官以及整株生物量分配,建立以胸径为变量的各林龄尾巨桉人工林不同器官的数学模型,为桉树人工林乔木层碳储量的准确测算提供科学依据和数据支持。结果表明:各林龄尾巨桉的根系,随径级的增加,细根和中根差异不大,而大根显著增大,且随着林龄的增大,大根比例迅速增加,细根和中根比例逐渐降低。各林龄尾巨桉不同器官的生物量分配均是树干>树根>树枝>树皮>叶片,2 a生、6 a生及10 a生尾巨桉林分总生物量分别为47.18 t·hm^-2、85.09 t·hm^-2和254.36 t·hm^-2,不同林龄各器官的生物量与胸径的拟合方程R^2在0.450~0.989之间,且均达到极显著水平,说明各林龄不同器官的模型方程均适用于尾巨桉乔木层生物量的估测。In view of the difficulties of estimating biomass of Eucalyptus plantations and the low precision of estimates obtained,a study was carried out to examine root biomass,above-ground biomass and the biomass distribution in plantations of different ages,and then model biomass measures to the variable of diameter at breast height(DBH).Development of such a mathematical model of biomass components of E.urophylla×E.grandis plantations provides support for accurate calculation of arbor layer carbon storage in eucalypt plantations.The result shows that with increasing DBH,the biomass of fine roots and mid-sized roots at different plantation ages shows little difference,while the large roots increase significantly.With increasing plantation age,the proportion of large roots increases rapidly while the proportion of fine roots and middle roots gradually decreases.The amount of biomass allocated to different tree component organs in E.urophylla×E.grandis plantations followed the order:stem>tree root>branch>bark>leaf.The total biomass of 2-year-old,6-year-old and 10-year-old E.urophylla×E.grandis plantations were 47.18 t·hm^-2,85.09 t·hm^-2 and 254.36 t·hm^-2 respectively.The correlation(R^2)between biomass components and DBH across ages ranged between 0.45 and 0.99,depending on the component organ;all correlations were highly significant indicating that the regression model equations were accurate for estimation of biomass of E.urophylla×E.grandis from tree DBH.

关 键 词：尾巨桉 人工林 根系特征 生物量 回归模型 

分 类 号：S718.5[农业科学—林学]