生态环境学报2025，Vol.34Issue(12)：1879-1889,11.DOI:10.16258/j.cnki.1674-5906.2025.12.005
土壤硝化N2O排放时空动态对退化热带森林恢复的响应
Response of Spatiotemporal Variation in Soil N2O Emissions from Nitrification to the Restoration of Degraded Tropical Forests
摘要
Abstract
Nitrification is a key microbial process that regulates the transformation of nitrogen nutrients in forest soils,from which nitrous oxide(N2O)is produced,affecting global climate change.Three tropical forests(i.e.,Mallotus paniculatus community at early restoration stage,Mellettia leptobotrya community at medium restoration stage,and Syzygium oblatum community at late restoration stage)were chosen to explore the impact of Xishuangbanna tropical forest restoration on N2O emission dynamics from soil nitrification.We also identified the linkage of wet-dry seasonal and vertical variation in soil N2O emissions from nitrification with environmental factors during tropical forest restoration,using an indoor continuous culture method of"acetylene inhibition of soil nitrification".The results showed that:1)Tropical forest restoration promoted N2O emissions from soil nitrification(p<0.01).The order of soil nitrification N2O emission rates in different restoration stages was as follows(taking N as an example):late recovery stage[(90.8±2.2)μg∙kg-1∙h-1]>medium recovery stage[(87.7±2.3)μg∙kg-1∙h-1]>early recovery stage[(57.5±2.5)μg∙kg-1∙h-1].2)Obvious seasonal variations were observed in N2O emission rates during soil nitrification during tropical forest restoration.The N2O emission rates were higher in wet season[(120.9±2.7)μg∙kg-1∙h-1]than in the dry season[(69.8±1.52)μg∙kg-1∙h-1];they had the largest variation[(74.5±2.5-144.1±5.2)μg∙kg-1∙h-1]in the medium recovery stage,with a variation coefficient of 48.30%.3)N2O emissions from nitrification decreased along the soil profile during tropical forest restoration.The greatest variation in N2O emissions[(58.7-219.3)μg∙kg-1∙h-1]was observed in the later stages of recovery.The N2O emissions from nitrification in the 0-5 cm soil layer accounted for more than 50.0%of the total emissions in the 0-15 cm soil layer.4)Changes in soil physicochemical properties during tropical forest restoration significantly affected nitrification-derived N2O emissions.Soil temperature,water content,and their interactions significantly affected the dynamics of N2O emissions from nitrification,with soil temperature and water content accounting for 52.0%-58.2%and 60.7%-71.4%of the variation in N2O emissions,respectively.Correlation analysis showed that N2O emissions from nitrification were significantly positively correlated with soil ammonium nitrogen(r=0.822;p<0.01),soil organic carbon,microbial biomass carbon,total nitrogen,and pH(r=0.460-0.646;p<0.05),but negatively correlated with soil bulk density(r=-0.589;p<0.05).The results of the structural equation showed that the soil nitrogen component,carbon component,and bulk density explained 67.3%,53.4%,and 41.7%of the changes in N2O emissions,respectively.Therefore,the restoration of tropical forests can regulate N2O emissions from nitrification,primarily by mediating changes in soil nitrogen components,particularly the ammonium nitrogen concentration.关键词
森林恢复/硝化作用/N2O排放/退化热带森林/时空动态/西双版纳Key words
forest restoration/nitrification/N2O emissions/restored tropical forests/spatiotemporal dynamics/Xishuangbanna分类
农业科技引用本文复制引用
颜营林,李少辉,王邵军,曹子林,曹乾斌,左倩倩,陈闽昆..土壤硝化N2O排放时空动态对退化热带森林恢复的响应[J].生态环境学报,2025,34(12):1879-1889,11.基金项目
国家自然科学基金项目(32271722 （）
32060281) （）
