摘要
为探明热带森林恢复对土壤反硝化N_(2)O排放时空动态的影响,选择西双版纳热带森林不同恢复阶段白背桐(Mallotus paniculatus)、崖豆藤(Mellettia leptobota)、高檐蒲桃(Syzygium oblatum)群落为研究对象,反硝化N_(2)O排放及微生物多样性分别采用“纯氧法抑制反硝化”和高通量测序测定,并分析其与土壤化学性质之间的关联特征。结果表明,1)热带森林恢复显著影响土壤反硝化N_(2)O排放速率(P<0.05),其速率均值(μg·kg^(-1)·h^(-1))大小依次为高檐蒲桃(303.16±37.57)>崖豆藤(251.38±28.37)>白背桐(193.45±26.76)。2)反硝化N_(2)O排放速率具有显著的时空变化,季节动态表现为湿季(6月和9月)显著高于干季(3月和12月),且干湿季变幅表现为白背桐(2.94倍)>高檐蒲桃(2.50倍)>崖豆藤(2.22倍);垂直变化随土层加深逐渐降低。3)不同恢复阶段土壤水分、微生物生物量碳及Shannon多样性对反硝化N_(2)O排放速率的解释量随恢复年限呈增加趋势,其大小顺序分别为:高檐蒲桃(68.77%,70.45%,97.87%)>崖豆藤(62.54%,57.16%,96.8%)>白背桐(54.56%,46.46%,93.17%)。4)主成分分析表明,土壤有机碳、易氧化有机碳、Shannon指数、含水率、微生物量碳是调控土壤反硝化N_(2)O排放的主控因子,而全氮、硝态氮、铵态氮、水解氮、Chao指数、Simpson指数的贡献次之。热带森林恢复通过影响土壤反硝化微生物Shannon多样性、水分及碳库组分含量,进而调控反硝化过程的N_(2)O排放的时空动态。
This study aimed to explore the effect of tropical forest restoration on the spatiotemporal dynamics of N_(2)O emissions from soil denitrification.The continuous indoor-culture method(pure-oxygen inhibition denitrification)and high-throughput metagenomic sequencing technology were used to determine the N_(2)O emissions and microbial diversity in tropical forests(i.e.,Mallotus paniculatus,Mellettia leptobota,and Syzygium oblatum communities)at different restoration stages in Xishuangbanna.We also determined the linkage of denitrifying N_(2)O emission with soil microbial diversity and chemical properties.The results showed that 1)tropical forest restoration significantly affected the N_(2)O emissions from soil denitrification(P<0.05).The average emission rates were ranked as S.oblatum(303.16±37.57)>M.leptobota(251.38±28.37)>M.paniculatus(193.45±26.76μg·kg^(-1)·h^(-1)).2)N_(2)O emission rates of denitrification had a significant spatio-temporal variation.They were significantly higher in the wet season(June and September)than in the dry season(March and December);the range of the fluctuations in N_(2)O emission rates from wet to dry season ranked as M.paniculatus(2.94 times)>S.oblatum(2.50 times)>M.leptobota(2.22 times);the vertical variation decreased along the soil profile.3)The explanatory order of soil water content,microbial biomass carbon and Shannon diversity for the changes of denitrifying N_(2)O emissions at the three restoration stages was ranked as S.oblatum(68.77%,70.45%,and 97.87%)>M.leptobota(62.54%,57.16%,and 96.8%)>M.paniculatus(54.56%,46.46%,and 93.17%).4)The result of principal component analysis showed that total organic carbon,readily oxidizable carbon,Shannon index,water content,and microbial carbon were the main factors regulating the N_(2)O emissions from denitrification.The contribution of total,nitrate,ammonium,and hydrolyzed nitrogen,Chao index,and Simpson index ranked the second.Tropical forest restoration can regulate the spatiotemporal variations in N_(2)O emission during soil deni
作者
张路路
王邵军
张昆凤
樊宇翔
解玲玲
肖博
王郑钧
郭志鹏
郭晓飞
罗双
李瑞
夏佳慧
杨胜秋
兰梦杰
ZHANG Lu-lu;WANG Shao-jun;ZHANG Kun-feng;FAN Yu-xiang;XIE Ling-ling;XIAO Bo;WANG Zheng-Jun;GUO Zhi-peng;GUO Xiao-fei;LUO Shuang;LI Rui;XIA Jia-hui;YANG Sheng-qiu;LAN Meng-jie(College of Ecology and Environment,Southwest Forestry University,Kunming 650224,Yunnan,China)
出处
《西北林学院学报》
CSCD
北大核心
2024年第2期97-105,共9页
Journal of Northwest Forestry University
基金
国家自然科学基金项目(32060281,31660191)
云南省一流学科建设项目(云转发[2022]73号)
云南省教育厅科学研究基金项目(2019Y0136)。
