摘要
探究生物因子和非生物因子与土壤有机碳含量的关系,解析影响土壤有机碳含量变异的主导因素,可为生态系统碳平衡协调发展提供理论依据。以北京山区针阔混交林为研究对象,基于64个样地的实测数据,采用结构方程模型筛选出影响土层(0-10、10-20、20-30 cm)有机碳含量的主导因素,并结合结构方程模型探究了各因子对土壤有机碳含量的直接和间接影响。结果表明,(1)林龄、根系生物量、凋落物质量、土壤全氮和土壤容重对0-10 cm的土壤有机碳含量的影响极显著(P<0.01),植物多样性对0-10 cm的土壤有机碳含量影响显著(P<0.05);直接效应依次为土壤全氮(0.73)>根系生物量(0.59)>凋落物质量(0.56)>林龄(0.47)>土壤容重(-0.44)>物种香农维纳指数(0.21),间接效应依次为林龄(0.31)>根系生物量(0.29)>凋落物质量(0.27)>物种香农维纳指数(0.11)。(2)海拔、土壤全氮和土壤容重对10-20 cm的土壤有机碳含量影响极显著(P<0.01),根系生物量、林龄对10-20 cm的土壤有机碳含量影响显著(P<0.05);直接效应依次为土壤全氮(0.69)>土壤容重(-0.53)>海拔(0.32)>根系生物量(0.27)>林龄(0.24),间接效应依次为海拔(0.23)>林龄(0.14)>根系生物量(0.09)。(3)海拔、土壤全氮和土壤容重对20-30 cm的土壤有机碳含量影响极显著(P<0.01),pH值对20-30 cm的土壤有机碳含量影响显著(P<0.05);直接效应依次为土壤全氮(0.59)>土壤容重(-0.47)>海拔(0.43)>pH值(-0.15),间接效应依次为海拔(0.14)>pH值(-0.04)。综上,土壤全氮和土壤容重主要通过直接作用影响土壤有机碳含量,而根系生物量、凋落物质量、林龄、植物多样性、土壤pH值对土壤有机碳含量不仅存在直接影响,而且还通过其他因子的作用而产生间接影响。
Exploring the relationships between biological factors(i.e.,plant diversity,litter quality,root biomass,and forest age),abiotic factors(i.e.,topography,soil physical and chemical properties)and soil organic carbon content,and analyzing the dominant factors affecting the variation of soil organic carbon content can provide a theoretical basis for coordinated development of forest ecosystem carbon balance in Beijing mountainous areas.In this paper,the mixed coniferous and broad-leaved forests in Beijing mountainous area were taken as the research object.Based on the measured data of 64 sample plots,the dominant factors affecting soil organic carbon content(0–10 cm,10–20 cm,20–30 cm)were selected by structural equation model,and the direct and indirect effects of each factor on soil organic carbon content were explored with structural equation model.The results showed that(1)root biomass,litter quality,soil total nitrogen and soil bulk density had a significant effect on the organic carbon content of surface soil(P<0.01),and plant diversity significantly affected the organic carbon content of surface soil(P<0.05).The direct effects revealed that soil total nitrogen(0.73)>root biomass(0.59)>litter quality(0.56)>stand age(0.47)>soil bulk density(0.44)>Shannon Wiener index(0.21),and the indirect effects showed that stand age(0.31)>root biomass(0.29)>litter quality(0.27)>Shannon Wiener index(0.11).(2)Altitude,soil total nitrogen and soil bulk density had a significant effect on the organic carbon content of 10–20 cm soil(P<0.01),and root biomass and stand age significantly affected the organic carbon content of 10–20 cm soil(P<0.05).The direct effects followed the order:soil total nitrogen(0.69)>soil bulk density(0.53)>altitude(0.32)>root biomass(0.27)>stand age(0.24),and the indirect effects followed the order:altitude(0.23)>stand age(0.14)>root biomass(0.09).(3)Altitude,soil total nitrogen and soil bulk density had a significant effect on soil organic carbon content in 20–30 cm(P<0.01),and pH value signifi
作者
张林
齐实
周飘
伍冰晨
张岱
张岩
ZHANG Lin;QI Shi;ZHOU Piao;WU Bingchen;ZHANG Dai;ZHANG Yan(School of Soil and Water Conservation,Beijing Forestry University,Beijing 100083,P.R.China)
出处
《生态环境学报》
CSCD
北大核心
2023年第3期450-458,共9页
Ecology and Environmental Sciences
基金
北京市京津风沙源治理二期工程2020年项目林业监测与评价(2020-SYZ-01-17JC05)。
关键词
针阔混交林
土壤有机碳含量
影响因素
结构方程模型
mixed coniferous and broad-leaved forests
soil organic carbon content
influencing factors
structural equation model
