Filling the“vertical gap”between canopy tree species and understory shrub species:biomass allometric equations for subcanopy tree species  

作　　者：Xue Sun Xingchang Wang Chuankuan Wang Quanzhi Zhang Qingxi Guo 

机构地区：[1]Center for Ecological Research,Northeast Forestry University,Harbin 150040,People’s Republic of China [2]Key Laboratory of Sustainable Forest Ecosystem Management–Ministry of Education,Northeast Forestry University,Harbin 150040,People’s Republic of China

出　　处：《Journal of Forestry Research》2023年第4期903-913,共11页林业研究（英文版）

基　　金：supported by the National Key Research and Development Program(2021YFD220040105);National Natural Science Foundation of China(32171765).

摘　　要：Subcanopy tree species are an important component of temperate secondary forests.However,their biomass equations are rarely reported,which forms a“vertical gap”between canopy tree species and understory shrub species.In this study,we destructively sampled six common subcanopy species(Syringa reticulate var.amurensis(Rupr.)Pringle,Padus racemosa(Lam.)Gilib.,Acer ginnala Maxim.,Malus baccata(Linn.)Borkh.,Rhamnus davurica Pall.,and Maackia amurensis Rupr.et Maxim.)to establish biomass equations in a temperate forest of Northeast China.The mixed-species and species-specifi c biomass allometric equations were well fi tted against diameter at breast height(DBH).Adding tree height(H)as the second predictor increased the R^(2)of the models compared with the DBH-only models by–1%to+3%.The R^(2)of DBH-only and DBH-H equations for the total biomass of mixed-species were 0.985 and 0.986,respectively.On average,the biomass allocation proportions for the six species were in the order of stem(45.5%)>branch(30.1%)>belowground(19.5%)>foliage(4.9%),with a mean root:shoot ratio of 0.24.Biomass allocation to each specifi c component diff ered among species,which aff ected the performance of the mixed-species model for particular biomass component.When estimating the biomass of subcanopy species using the equations for canopy species(e.g.,Betula platyphylla Suk.,Ulmus davidiana var.japonica(Rehd.)Nakai,and Acer mono Maxim.),the errors in individual biomass estimation increased with tree size(up to 68.8%at 30 cm DBH),and the errors in stand biomass estimation(up to 19.2%)increased with increasing percentage of basal area shared by subcanopy species.The errors caused by selecting such inappropriate models could be removed by multiplying adjustment factors,which were usually power functions of DBH for biomass components.These results provide methodological support for accurate biomass estimation in temperate China and useful guidelines for biomass estimation for subcanopy species in other regions,which can help to improve estimate

关 键 词：Subcanopy tree species BIOMASS Allometric equations Temperate forests Biomass allocation 

分 类 号：S718.54[农业科学—林学]