Planting practices and mulching materials improve maize net ecosystem C budget, global warming potential and production in semi-arid regions

Planting and mulching practices have long been used to change soil water storage, which may increase crop yields in dry-land farming systems. But, few research works have focused on mulching practices on the greenhouse gas intensity (GHGI), global warming potential (GWP), and net ecosystem C budget (NECB). Therefore, a two years field study was carried out in 2017–2018 to evaluate NECB, GWP, GHGI, biomass and maize production under six treatments: RPS: ridge tillage with film mulch on ridges and straw on furrows; RP: ridge tillage with film mulch on ridges; RT: ridge tillage without film mulch; FM: film mulching; SM: straw mulching; CT: conventional tillage. Finding of our results showed that both plastic film and straw mulching under two planting methods considerable reduced (41.3 %) GHGI, and improving the maize production and soil water status. The RPS treatment improved the soil environment, thus significantly increased corn productivity, C breathing loss, NECB, GWP, N₂O, and CH₄ emissions. The improve in NPP through RPS treatment is higher than the C loss in respiration, but seasonal NECB shows larger negative values because more NPP is removed as grain and straw. In the RPS treatment increased (22.3 %) the net GWP over flat planting without mulched, but decreased GHGI, due to increased (42.1 %) biomass productivity. The RPS treatment results in higher N₂O, CO₂ emissions and GWP, and therefore, has an adverse impact on the environment compared to CT treatment. However, the higher WUEg (72.1 %), WUEb (34.4 %), biomass and (83.1 %) grain yields obtained through RPS treatment may balance the negative ecological impacts associated with climate change. Thus, under dry farming systems, RPS treatment may be an effective water-saving management strategy that can increase WUE, biomass, corn yield and reduce the impact of global warming by increasing crop yields.