南亚热带常绿阔叶林细根生物量年际动态及其环境影响因子  

Interannual Dynamics of Fine Root Biomass and Its Environmental Impact Factors in Subtropical Evergreen Broad-Leaved Forest

作　　者：付志高 肖以华[1] 许涵[1] 王焱 贲春丽 陈洁 史欣[1] FU Zhigao;XIAO Yihua;XU Han;WANG Yan;BEN Chunli;CHEN Jie;SHI Xin(Research Institute of Tropical Forestry,Chinese Academy of Forestry,Guangzhou 510520,China;Forestry College of Jiangxi Agricultural University,Nanchang 330006,China)

机构地区：[1]中国林业科学研究院热带林业研究所,广州510520 [2]江西农业大学林学院,南昌330006

出　　处：《四川农业大学学报》2025年第1期165-175,共11页Journal of Sichuan Agricultural University

基　　金：国家重点研发计划项目(2022YFF1303003-06);中央级公益性科研院所基本科研业务费专项(CAFYBB2021SY004);广东省科技厅林业生态监测网络平台建设(2024CG259);广东珠江三角洲森林生态系统国家定位观测研究站(0144135)。

摘　　要：【目的】细根对于森林生态系统中碳的分配和养分循环至关重要,了解影响细根生物量累积的环境因素对理解森林演替、养分循环和地下生态过程具有重要意义。【方法】通过原位监测南亚热带常绿阔叶林的细根生物量、土壤生物(微生物生物量碳和氮)、非生物(有机碳、总氮、总磷、可溶性碳、速效氮、铵态氮、硝态氮、pH、土壤温度和土壤含水量)以及气象(大气降水量、温度和湿度)等要素连续10年数据,探究生物与非生物因子和细根生物量累积的关系。【结果】①湿季(499.36 g/m^(2))较干季(289.61 g/m^(2))而言更有利于细根生物量累积(P<0.01),但湿季细根生物量于457.40~547.13 g/m^(2)区间相对稳定(P=0.097),而干季从157.80~348.53 g/m^(2)极显著变化(P<0.01)。年尺度上细根总生物量的变异与湿季类似,年际间保持相对稳定(P>0.05)。②干季FRB与SOC、MBN、NO_(3)^(-)-N和TP显著正相关,湿季,则与MBC和ST显著正相关。③气候条件(MAP、MAH和MAT)变化主要通过影响土壤因子间接影响细根生物量的累积,且其对土壤生物特性的影响(84%)大于非生物特性(74%)。干季土壤因子(R^(2)=0.65)对于细根生物量的影响高于湿季(R^(2)=0.39),土壤因子中,MBC(重要性值15.41%)和ROC(重要性值27.61%)分别是湿季和干季细根生物量变化的主导因子。年尺度上影响总细根生物量变异的主导因子则与湿季一致为MBC(29.30%)。【结论】南亚热带常绿阔叶林中,ROC和MBC是维持细根生物量年际稳定的主要土壤因子。【Objective】Fine roots are essential in forest systems for carbon alloction and nutrient cycling,and their biomass fluctuation significantly influences these processes.A better understanding of soil factors that influence fine root biomass accumulation aids in understanding forest succession,nutrient cycling,and below-ground ecological processes.【Method】This study investigated fine root biomass(FRB)dynamics in a subtropical evergreen broad-leaved forest over a 10-year period,encompassing both wet and dry seasons.We examined the relationships between FRB accumulation and key soil biotic properties(MBC and MBN),abiotic properties(SOC,TN,TP,ROC,AN,NH+4-N,NO_(3)^(-)-N,pH,ST and SWC),as well as meteorological conditions(atmospheric precipitation,temperature and humidity).Our goal was to elucidate the drivers of FRB accumulation and its inter-annual stability in response to seasonal and climatic variability.【Result】①FRB accumulation was significantly higher in the wet season(499.36 g/m^(2))than in the dry season(289.61 g/m^(2))(P<0.01).Inter-annual variation in FRB was not significant during the wet season(P>0.05),with values ranging from 457.40 to 547.13 g/m^(2).In contrast,significant inter-annual variation was observed in the dry season(P<0.01),where FRB fluctuated between 157.80 and 348.53 g/m^(2).On an annual scale,total FRB exhibited a pattern similar to that of the wet season,remaining relatively stable across years(P>0.05).2.FRB showed significant positive correlations with SOC,MBN,NO_(3)^(-)-N and TP during the dry season,and with MBC and ST during the wet season.3.Climatic factors indirectly affected FRB accumulation primarily through their effects on soil properties,with a stronger impact on soil biotic properties(84%of variance explained)than on abiotic properties(74%).Soil factors had a greater impact on FRB in the dry season(R^(2)=0.65)compared to the wet season(R^(2)=0.39).Specifically,MBC(general dominance value=15.41%)and ROC(general dominance value=27.61%)were identified as the primary de

关 键 词：年际变化特征 细根生物量 环境因子 南亚热带常绿阔叶林 

分 类 号：S718.5[农业科学—林学]