秦岭山地主要森林凋落物化学组分

Chemical composition of litters from main forests in Qinling Mountains

【目的】分析秦岭山地主要森林凋落物的化学组分,为应用Yasso07土壤碳模型估算和预测秦岭山地森林土壤有机碳变化动态提供必要参数。【方法】利用醇浸提法和酸碱洗涤法,测定生长于秦岭火地塘的华山松(Pinus armandi)、油松(Pinus tabulaeformis)、云杉(Picea asperata)、华北落叶松(Larix principis-rupprechtii)、锐齿栎(Quercus aliena var.acuteserrata)和红桦(Betula albo-sinensis)6个主要树种非木质凋落物、细木质凋落物、粗木质凋落物中的醇溶性(ESC)、水溶性(WSC)、酸溶性(ASC)和不溶性(NSC)4类化合物的含量。【结果】(1)不同树种凋落物的化学组分含量差异显著(P<0.05),针叶树种凋落物中ESC、WSC、ASC和NSC的含量分别为(78.23±39.51)^(102.11±40.48)g/kg、(106.43±36.66)^(144.25±60.02)g/kg、(482.09±73.01)^(507.09±56.58)g/kg和(277.42±25.13)^(314.03±16.08)g/kg;阔叶树种的凋落物中ESC、WSC、ASC和NSC的含量则分别为(111.63±68.24)^(129.99±39.10)g/kg、(158.64±70.36)^(184.96±51.20)g/kg、(452.28±51.95)^(489.56±52.39)g/kg和(232.77±44.44)^(240.17±94.81)g/kg。(2)各树种不同凋落物类型间化学组分含量差异显著(P<0.05),非木质、细木质和粗木质凋落物中的ESC、WSC、ASC和NSC的含量分别为(21.27±4.12)^(175.77±24.30)g/kg、(53.30±2.40)^(237.10±29.73)g/kg、(404.23±15.79)^(597.45±4.88)g/kg和(166.11±69.77)^(327.98±4.91)g/kg。(3)聚类分析结果表明,秦岭山地主要树种凋落物可分为两大类,华山松、油松、华北落叶松和云杉这4种针叶树种聚为一类,红桦和锐齿栎这2种阔叶树种聚为一类。【结论】在不同区域应用Yaso07土壤碳模型时,不宜直接采用模型提供的凋落物4类化合物含量参数。

【Objective】The study analyzed chemical composition of litters from main forests in Qinling Mountains to provide necessary parameters for the application of Yasso07 soil carbon model to estimate and predict forest soil organic carbon dynamics.【Method】Litters were collected from common forests Pinus armandi,Pinus tablulaeformis,Picea asperata,Larix principis-rupprechtii,Quercus aliena var.acuteserrataand Betula albo-sinensis in Qinling Mountains and main chemical components including ethanol solublecompounds（ESC）,water soluble compounds（WSC）,acid soluble compounds（ASC）and non-soluble compounds（NSC）were detected by alcohol extraction method as well as acid and alkali washing method.【Result】（1）Compounds of litters from different forests had significant differences（P〈0.05）.The concentrations of compounds in coniferous litter were（78.23±39.51）-（102.11±40.48）g/kg（ESC）,（106.43±36.66）-（144.25±60.02）g/kg（WSC）,（482.09±73.01）-（507.09±56.58）g/kg（ASC）,and（277.42±25.13）-（314.03±16.08）g/kg（NSC）,while those in broad-leaf litters were（111.63±68.24）-（129.99±39.10）g/kg（ESC）,（158.64±70.36）-（184.96±51.20）g/kg（WSC）,（452.28±51.95）-（489.56±52.39）g/kg（ASC）,and（232.77±44.44）-（240.17±94.81）g/kg（NSC）,respectively.（2）Concentrations of compounds among litter types differed significantly.The concentrations of compounds in non-woody,fine and coarse woody litters were（21.27±4.12）-（175.77±24.30）g/kg（ESC）,（53.30±2.40）-（237.10±29.73）g/kg（WSC）,（404.23±15.79）-（597.45±4.88）g/kg（ASC）,and（166.11±69.77）-（327.98±4.91）g/kg（NSC）,respectively.（3）Clustering analysis showed that the litters of main forests in Qinling Mountains can be divided into two main categories,one with P.armandi,P.tablulaeformis,P.asperata and L.principis-rupprechtii while one with Q.aliena var.acuteserrataand B.albo-sinensis.【Conclusion】Parameters in Yasso07 manual cannot be used directly when the model is applied in different forest areas.