Background:Nitrogen(N)deposition affects soil greenhouse gas(GHG)emissions,while biochar application re-duces GHG emissions in agricultural soils.However,it remains unclear whether biochar amendment can alleviate the promoting effects of N input on GHG emissions in forest soils.Here,we quantify the separate and combined effects of biochar amendment(0,20,and 40 t·ha-1)and N addition(0,30,60,and 90 kg N·ha-1·yr-1)on soil GHG fluxes in a long-term field experiment at a Moso bamboo(Phyllostachys edulis)plantation.Results:Low and moderate N inputs(≤60 kg N·ha-1·yr-1)significantly increase mean annual soil carbon dioxide(CO2)and nitrous oxide(N2O)emissions by 17.0％-25.4％and 29.8％-31.2％,respectively,while decreasing methane(CH4)uptake by 12.4％-15.9％,leading to increases in the global warming potential(GWP)of soil CH4 and N2O fluxes by 32.4％-44.0％.Moreover,N addition reduces soil organic carbon(C;SOC)storage by 0.2％-6.5％.Compared to the control treatment,biochar amendment increases mean annual soil CO2 emissions,CH4 uptake,and SOC storage by 18.4％-25.4％,7.6％-15.8％,and 7.1％-13.4％,respectively,while decreasing N2O emissions by 17.6％-19.2％,leading to a GWP decrease of 18.4％-21.4％.Biochar amendments significantly enhance the promoting effects of N addition on soil CO2 emissions,while substantially offsetting the promotion of N2O emissions,inhibition of CH4 uptake,and decreased SOC storage,resulting in a GWP decrease of 9.1％-30.3％.Additionally,soil CO2 and CH4 fluxes are significantly and positively correlated with soil microbial biomass C(MBC)and pH.Meanwhile,N2O emissions have a significant and positive correlation with soil MBC and a negative correlation with pH.Conclusions:Biochar amendment can increase SOC storage and offset the enhanced GWP mediated by elevated N deposition and is,thus,a potential strategy for increasing soil C sinks and decreasing GWPs of soil CH4 and N2O under increasing atmospheric N deposition in Moso bamboo plantations.

Quan Li;Kunkai Cui;Jianhua Lv;Junbo Zhang;Changhui Peng;Yongfu Li;Zhikang Gu;Xinzhang Song

State Key Laboratory of Subtropical Silviculture,Zhejiang A&F University,Hangzhou,311300,PR China;Institute of Environment Sciences,Department of Biology Sciences,University of Quebec at Montreal,Case Postale 8888,Succursale Centre-Ville,Montreal,H3C3P8,Canada;Huzhou Research Center of Ecological Forestry and Protection,Huzhou,313000,PR China

森林生态系统（英文版）

[1]Quan Li;Kunkai Cui;Jianhua Lv;Junbo Zhang;Changhui Peng;Yongfu Li;Zhikang Gu;Xinzhang Song-.Biochar amendments increase soil organic carbon storage and decrease global warming potentials of soil CH4 and N2O under N addition in a subtropical Moso bamboo plantation)[J].森林生态系统（英文版）,2022(04):567-576

Moso,GWPs

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