亚热带不同植被恢复林地凋落物层碳、氮、磷化学计量特征  

C,N and P stoichiometry characteristics of forest floor litter layer at different vegetation restoration stages in the mid-subtropical regions,China

作　　者：杜雨潭 陈金磊 李雷达[1] 辜翔[1] 刘兆丹 苏元博 方晰[1,2] DU Yutan;CHEN Jinlei;LI Leida;GU Xiang;LIU Zhaodan;SU Yuanbo;FANG Xi(College of Life Science and Technology,Central South University of Forestry and Technology,Changsha 410004,Hunan,China;National Engineering Laboratory for Applied Forest Ecological Technology in Southern China,Changsha 410004,Hunan,China)

机构地区：[1]中南林业科技大学生命科学与技术学院,湖南长沙410004 [2]南方林业生态应用技术国家工程实验室,湖南长沙410004

出　　处：《中南林业科技大学学报》2020年第2期108-119,共12页Journal of Central South University of Forestry & Technology

基　　金：国家林业公益性行业科研专项(201504411)

摘　　要：【目的】探究不同植被恢复阶段林地凋落物层现存量及其碳(C)、氮(N)、磷(P)化学计量的差异,为亚热带地区退化林地的植被恢复和管理提供科学依据。【方法】采用空间代替时间的方法,在位于亚热带丘陵区的湖南省长沙县选取地域相邻、环境条件基本一致的4种处于不同植被恢复阶段林地:檵木-南烛-杜鹃灌草丛(LVR)、檵木-杉木-白栎灌木林(LCQ)、马尾松-柯(又名石栎)-檵木针阔混交林(PLL)、柯-红淡比-青冈常绿阔叶林(LAG)作为一个恢复序列,设置固定样地,按未分解层、半分解层和已分解层采集凋落物层分析样品,测定凋落物层现存量以及不同分解层凋落物C、N、P含量及其化学计量比。【结果】1)凋落物层及其各分解层凋落物的现存量总体上随着植被恢复而增加,同一林地不同分解层表现为:已分解层>半分解层>未分解层,不同分解层之间的差异随着植被恢复而增大。2)凋落物层C含量以PLL最高,LCQ最低,而N、P含量总体上随着植被恢复而增高;C、N、P含量随着凋落物的分解而下降。3)无论是整个凋落物层C储量还是各分解层凋落物C储量,均以PLL最高,其次是LAG,LVR最低,而N、P储量随着植被恢复而增高。4)整个凋落物层以及各分解层凋落物的C/N比值均表现为:PLL>LVR>LCQ>LAG,而C/P、N/P比值总体上随着植被恢复呈下降趋势;C/N、C/P、N/P比值基本上随着凋落物的分解而下降。【结论】随着植被恢复,凋落物层现存量及其N、P含量增加,C/N、C/P、N/P比值下降,体现了生态系统物质循环随着植被恢复逐渐优化。【Objective】In order to explore the difference of litter layer existing amount and its carbon(C),nitrogen(N),phosphorus(P)stoichiometry in different vegetation restoration stages,so as to provide scientific basis for vegetation restoration and management of degraded forest land in subtropical region.【Method】By using the space-for-time substitution method,we selected four different types of plant communities,comprising of Loropetalum chinense+Vaccinium bracteatum+Rhododendron simsii scrub-grass-land(LVR),Loropetalum chinense+Cunninghamia lanceolata+Quercus fabri shrubbery(LCQ),Pinus massoniana+Lithocarpus glaber+Loropetalum chinense coniferous-broad leaved mixed forest(PLL),and Lithocarpus glaber+Cleyera japonica+Cyclobalanopsis glauca evergreen broad-leaved forest(LAG)to represent the vegetation restoration sequence in the secondary forests in the hilly area of central Hunan province,China.Based on decomposition state,the litter on the forest floor was divided into un-decomposed layer,semi�decomposed layer,and decomposed layer.Litter samples were taken from these three layers separately in fixed plots in the four forests.Concentrations of C,N and P in litter sample were analyzed and the ratios of C/N,C/P and N/P were estimated,and the dynamics of C,N,P in litter layer with vegetation restoration were discussed.【Result】1)On the whole,the stocks of litter layers and its different decomposed layers increased with vegetation restoration.The stocks of different decomposed layers in the same forest were in the order as follows:decomposed layer>semi-decomposed layer>un-decomposed layer,and the differences of different decomposed layers were increased with vegetation restoration.2)Concentrations of C in the litter layer was the highest in PLL and the lowest in LCQ,while concentrations of N and P increased with the restoration of vegetation.Concentrations of C,N and P decreased with the decomposition of litter.3)Both the C storage in litter layers and in different decomposed layers were the higest in PLL,foll

关 键 词：湘中丘陵区 植被恢复 地表凋落物 分解层 C、N、P含量 化学计量比 

分 类 号：S714.2[农业科学—林学]