凋落物输入对马尾松细根生长及化学计量的影响  

Effects of Litter Input on the Growth and Stoichiometry of Fine Roots of Pinus massoniana

作　　者：蔡银美 张成富 李昕颖 何腾兵[1] 赵庆霞 Cai Yinmei;Zhang Chengfu;Li Xiying;He Tengbing;Zhao Qingxia(Guizhou University,Guiyang 550025,P.R.China;Guizhou Institute of Mountain Resources)

机构地区：[1]贵州大学,贵阳550025 [2]贵州省山地资源研究所

出　　处：《东北林业大学学报》2022年第6期32-38,共7页Journal of Northeast Forestry University

基　　金：贵州省林业青年项目(黔林科合J(2018)06号);国家自然科学基金项目(32060339)。

摘　　要：以35年生马尾松人工林为研究对象,采用内生长袋法,研究凋落物处理(自然条件为对照(CK)、凋落物去除(LR)及凋落物添加(LA))对马尾松人工林细根生产量、形态特征、细根碳(C)、氮(N)、磷(P)质量分数及其化学计量比垂直分布的影响。结果表明,马尾松人工林细根年生产量为57.55 g·m^(-2)·a^(-1),LA和LR处理对细根生产量的影响不显著,与30~40 cm土层相比,0~10、10~20、20~30 cm土层细根生产量较高,细根集中生长在0~30 cm土层。LR处理显著增加了0~10 cm土层细根的比根长和比表面积,增加了细根养分和水分的吸收效率。细根直径、根长密度、表面积密度、体积密度整体随土壤深度的加深逐渐减小。细根碳(C)质量分数在不同凋落物处理间无明显差异,氮(N)质量分数总体表现为LR和LA处理大于CK,磷(P)质量分数由大到小表现为LR、CK、LA,LA处理提高了细根w(C)∶w(P)和w(N)∶w(P),LR处理降低了细根w(C)∶w(P)和w(N)∶w(P)。土壤深度均显著影响细根N、P质量分数及w(C)∶w(P)、w(N)∶w(P),细根N质量分数在0~10、10~20、20~30 cm土层呈逐渐下降趋势,P质量分数在0~10、30~40 cm土层较高,细根w(C)∶w(P)在0~10 cm土层较低,w(N)∶w(P)表现为0~10 cm土层高于30~40 cm土层。综上,凋落物输入量的改变一定程度上影响细根养分含量及细根对土壤养分的吸收利用状况,但对细根垂直生长的影响并不显著。The experiment was conducted to clarify the effects of control(CK),litter removal(LR)and litter addition(LA)on the fine root production,morphological characteristics,fine root C,N,P content and stoichiometry of 35-year-old Pinus massoniana plantations by ingrown bag method.The annual fine root production of P.massoniana plantation was 57.55 g·m^(-2)·a^(-1).LA and LR have no significant effect on the fine root production.The fine root production in the soil layer of 0-10,10-20,and 20-30 cm is higher than that of 30-40 cm,and the fine root is concentrated in the soil layer of 0-30 cm.LR significantly increased the specific root length and specific surface area of the fine root in the 0-10 cm soil layer,and the purpose was to increase the nutrient and water absorption efficiency.Fine root diameter,root length density,surface area density,and bulk density gradually decrease with the depth of soil.There was no significant difference in fine root C content between different litter treatments.For N content,LR and LA were greater than CK,for P content the descending order was LR,CK and LA.LA increased fine root w(C)∶w(P)and w(N)∶w(P),and LR decreased the fine root w(C)∶w(P)and w(N)∶w(P).The soil layer significantly affects the N and P content of fine root and w(C)∶w(P),w(N)∶w(P).The N content of fine root in the 0-10,10-20,and 20-30 cm soil layer showed a gradual downward trend,and the P content is 0-10,30-40 cm soil layer is higher,w(C)∶w(P)is lower in 0-10 cm soil layer,w(N)∶w(P)in 0-10 cm soil layer is higher than that in 30-40 cm soil layer.Therefore,changes in litter input affect the nutrient content of fine root and the absorption and utilization of soil nutrients by fine root to a certain extent,but the effect on the vertical growth of fine root is not significant.

关 键 词：凋落物 马尾松 细根 化学计量 

分 类 号：S718.55[农业科学—林学]