Integrating organic fertilizers in maize-mung bean intercropping: implications for soil carbon dynamics and greenhouse gas reduction

Abstract

Organic fertilizers have great potential to improve crop production while reducing greenhouse gas (GHG) emissions in agroecosystems. To study their effect on GHG emissions, a field experiment over a two-year period (2021 and 2022) was carried out to quantify carbon dioxide ( CO2) and nitrous oxide ( N2O) emissions. Experimental treatments included: (i) two types of organic fertilizers [wheat residue (WR) and sheep manure (SM)]; and (ii) three cropping systems [monocropping of maize (Zea mays L., Ma) and mung bean (Vigna radiata (L.) R. Wilczek, Mu), and their intercropping (Ma + Mu)]. Total crop biomass and its carbon (C) and nitrogen (N) content, soil CO2 and N2O emissions, soil temperature and moisture were measured. The results showed that Ma + Mu_WR significantly reduced cumulative CO2 emissions by 36% and 28% compared to the Ma_ WR and Mu_WR, respectively. Similarly, Ma + Mu_ SM reduced soil CO2 emissions by 38% and 70%