Soil carbon sequestration, greenhouse gas emissions, and water pollution under different tillage practices

Tillage is a common agricultural practice and a critical component of agricultural systems that is frequently employed worldwide in croplands to reduce climatic and soil restrictions while also sustaining various ecosystem services. Tillage can affect a variety of soil-mediated processes, e.g., soil carbon sequestration (SCS) or depletion, greenhouse gas (GHG) (CO2, CH4, and N2O) emission, and water pollution. Several tillage practices are in vogue globally, and they exhibit varied impacts on these processes. Hence, there is a dire need to synthesize, collate and comprehensively present these interlinked phenomena to facilitate future researches. This study deals with the co-benefits and trade-offs produced by several tillage practices on SCS and related soil properties, GHG emissions, and water quality. We hypothesized that improved tillage practices could enable agriculture to contribute to SCS and mitigate GHG emissions and leaching of nutrients and pesticides. Based on our current understanding, we conclude that sustainable soil moisture level and soil temperature management is crucial under different tillage practices to offset leaching loss of soil stored nutrients/pesticides, GHG emissions and ensuring SCS. For instance, higher carbon dioxide (CO2) and nitrous oxide (N2O) emissions from conventional tillage (CT) and no-tillage (NT) could be attributed to the fluctuations in soil moisture , temperature regimes. In addition, NT may enhance nitrate (NO3-) leaching over CT because of improved soil structure, infiltration capacity , greater water flux, however, suggesting that the eutrophication potential of NT is high. Our study indicates that the evaluation of the eutrophication potential of different tillage practices is still overlooked. Our study suggests that improving tillage practices in terms of mitigation of N2O emission and preventing NO3- pollution may be sustainable if nitrification inhibitors are applied.