南京林业大学学报（自然科学版）2026，Vol.50Issue(4)：136-145,10.DOI:10.12302/j.issn.1000-2006.202501018
氮沉降背景下杨树人工林根际和非根际土壤颗粒有机碳和矿物结合态有机碳变化特征
Changes of particulate organic carbon and mineral-associated organic carbon in rhizosphere and bulk soil of poplar plantation under nitrogen deposition
摘要
Abstract
[Objective]Global nitrogen deposition may have significant impacts on ecosystem functions.Studying the differences in soil organic carbon(SOC)between rhizosphere and bulk soils and their responses to nitrogen deposition can provide a theoretical basis for further understanding the response and adaptation mechanisms of forest SOC cycling under future nitrogen deposition scenarios.[Method]Taking the poplar plantation as the object,five nitrogen deposition treatments[0,5,10,15,30g/(m2.a),denoted as:N0,N1,N2,N3,N4]were set up in May 2012,and simulated nitrogen deposition treatments were carried out every year starting from that year.Soil samples from the rhizosphere and bulk were collected in July 2023(summer,vigorous growth period),October 2023(autumn,growth end period),January 2024(winter,non-growth period),and April 2024(spring,early growth period).Determine the contents of soil particulate organic carbon(POC),mineral-associated organic carbon(MAOC),SOC,pH,soil moisture content(SWC),microbial biomass carbon and nitrogen(MBC,MBN),total nitrogen(TN),and other related soil physical and chemical properties.Based on analysis of variance,independent sample T-test,correlation analysis and redundancy analysis,etc.,the variation characteristics of POC and MAOC in rhizosphere and bulk soils under nitrogen deposition treatment were quantified,and the key factors driving the changes in their contents were analyzed.[Result](1)Nitrogen deposition increased the POC concentration in rhizosphere soil.Compared with the NO treatment,the annual average POC concentration in rhizosphere soil increased by 6.35％(N1),19.46％(N2),20.28％(N3),and 28.83％(N4).Nitrogen deposition had no effect on the POC concentration in bulk soil.Nitrogen deposition had no significant effect on the MAOC concentration in rhizosphere and bulk soils and the ratios of POC/SOC and MAOC/SOC.Seasonally,the POC concentration in rhizosphere and bulk soils showed significant seasonal differences,specifically summer＞autumn＞winter＞spring;MAOC did not show significant seasonal differences.(2)Under the same nitrogen deposition treatment,the annual average POC concentration in rhizosphere soil was 29.51％(NO),33.06％(N1),59.90％(N2),48.77％(N3),and 49.67％(N4)higher than that in bulk soil,and the annual average MAOC concentration in rhizosphere soil was 41.78％(N0),52.45％(N1),32.05％(N2),59.73％(N3),and 48.63％(N4)higher than that in bulk soil.(3)Redundancy analysis revealed that pH,SOC,and SWC were the key factors driving the changes in POC and MAOC concentration in bulk soil,while MBC,pH,MBN,and TN were the key factors driving the changes in POC and MAOC concentration in rhizosphere soil.[Conclusion]Nitrogen deposition increased the POC concentration in rhizosphere soil,but had no significant effect on the POC and MAOC concentration in bulk soil and the MAOC concentration in rhizosphere soil.Under all nitrogen treatments,the POC and MAOC concentration in rhizosphere soil were higher than those in bulk soil.The results of this study reveal the differences in the main components of rhizosphere and bulk SOC and their different responses to nitrogen deposition,which can provide a theoretical basis for further exploring the response characteristics of SOC to nitrogen deposition.关键词
杨树人工林/氮沉降/根际土壤/非根际土壤/颗粒有机碳/矿物结合态有机碳Key words
poplar plantation/nitrogen deposition/rhizosphere soil/bulk soil/particulate organic carbon/mineral-associated organic carbon分类
农业科技引用本文复制引用
高雪萍,刘晖晖,施政,方玉,阮宏华,沈彩芹,徐亚明,霍建军,曹国华..氮沉降背景下杨树人工林根际和非根际土壤颗粒有机碳和矿物结合态有机碳变化特征[J].南京林业大学学报（自然科学版）,2026,50(4):136-145,10.基金项目
江苏省林业局揭榜挂帅项目(LYKJ[2022]01) （LYKJ[2022]01）
国家重点研发计划(2023YFD2200404 （）
2021YFD2200403) （）
江苏省林业局造林专项项目([2021-2022]). （[2021-2022]）
