AUTHOR=Jia Xiaoyu , Yan Weiming , Ma Hongze , Shangguan Zhouping 

TITLE=Antagonistic and synergistic interactions dominate GHGs fluxes, soil properties and yield responses to biochar and N addition

JOURNAL=Frontiers in Environmental Science

VOLUME=Volume 11 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/environmental-science/articles/10.3389/fenvs.2023.1123897

DOI=10.3389/fenvs.2023.1123897

ISSN=2296-665X

ABSTRACT=Applying biochar to soil has been advocated as an effective measure to improve soil fertility and increase carbon (C) sequestration. Biochar is often co-applied with nitrogen (N) fertilizers in agricultural ecosystems, however, the interactive effects of biochar and N addition (BN) on soil greenhouse gases (GHGs) fluxes, soil C and N fractions, and yield has not been investigated. Here, we manipulated a global meta-analysis to explore the effects of the additions of biochar and N and their interaction on the GHGs, soil C and N fractions, and yield by assembling 75 articles. Across all obtained studies, biochar, N, and BN additions all increased soil CO2 emissions (8.5%-29.6%), yield (4.2%-58.2%), soil organic C (SOC, 1.8%-50.4%), dissolved organic C (DOC, 2.7%-30.0%), and total N (TN, 6.8%-15.6%), but had no significant effect on CH4 fluxes. The addition of biochar reduced N2O emissions (-21.3%), global warming potential (GWP, -19.8%), greenhouse gas intensity (GHGI, -28.2%), NH4+ (-17.8%) and NO3- (-10.7%), whereas N addition increased these indexes. The interaction effects of BN on CO2 and N2O emissions, GWP, TN, and NH4+ contents were antagonistic, while CH4 emissions, DOC, MBC, NO3-, and yield exhibited synergistic responses. Notably, soil GHGs responses varied depending on geo-climatic factors, edaphic properties, biochar and N treatment parameters, and experimental scenarios. These findings indicate the potential of biochar and N co-addition to mitigate climate change and improve yield, providing a valuable reference for the improvement of climate-smart agriculture.