长白山区林下主要灌木生物量估算与分析

Estimation and analysis of understory shrub biomass in Changbai Mountains

以长白山金沟岭林场天然云冷杉林、杨桦次生林、人工落叶松林3种森林类型为研究对象,构建了林下灌木层分布较广泛的10个物种以植冠面积(Ac)、植冠体积(Vc)、地径平方与株高乘积(D2H)为自变量的器官生物量模型,并按照灌木形态的不同分别乔木型灌木(主干明显)、典型灌木(分枝多,主干不明显)构建混合物种模型,选出R2较大、SEE较小的模型作为最优模型,研究了不同森林类型林下灌木层生物量及其在不同物种和器官中的分配。结果表明:单一物种器官生物量最优模型多为线性、二次或者三次方程,干、枝最优模型采用的自变量多为D2H或者Vc,叶生物量最优模型采用的自变量多为Ac或者Vc,根的多为D2H。混合物种模型的最优方程为幂函数或三次方程,最优模型的自变量除典型灌木枝模型为Vc外,其他各器官模型自变量都为D2H。计算得到的天然云冷杉林、杨桦次生林、人工落叶松林林下灌木层生物量分别为4 013.59、3 950.66和4 649.36 kg/hm2,且乔木型灌木对生物量的贡献率大于典型灌木。

With 10 common species of understory shrub in three natural forest types,including Spruce-Fir Mixed forests,Polar-Birch secondary forests and Larch plantation in Jinggouling Plantation Changbai Mountains as test objects,crown area（Ac）,project volume（Vc）,square ground diameter by height（D2H） were used as variables in component biomass models.According to the growth forms,tree-like（single trunked） mixed models and shrub-like（multi-stemmed or low branching） mixed models were built.The shrub biomass along with its distribution in different species and components were investigated using the best-fit models which were judged by high R2 and low SEE.The results showed that the best-fit species-specific component model forms were linear,quadratic or cubic equations,the variables in stem and branch models were D2H or Vc,and in leaf models were Ac or Vc,while in root models were D2H.The best-fit mixed model forms were power or cubic equation,the variables in these models were D2H while the branch of mixed model of shurb-like plants was Vc.The biomass of understory shrub in natural Spruce-Fir Mixed forests,Polar-Birch secondary forests and Larch plantation was 4 013.59,3 950.66 and 4 649.36 kg/hm2 respectively,and tree-like plants make more biomass contribution than shrub-like plants.