Farming practices and deficit irrigation management improve winter wheat crop water productivity and biomass through mitigated greenhouse gas intensity under semi-arid regions.

Abstract

Understanding the greenhouse gas emissions mechanism from the agricultural soils is essential to reach an agricultural system with a lower impact on the environment. The cultivation practices in combination with deficit irrigation have been used in a dry-land farming system to modify the soil water status. However, few research works have been focused on plastic film with deficit irrigation regimes on global warming potential (GWP), greenhouse gas intensity (GHGI), and biomass productivity under simulated rainfall conditions. In the current study, a 2-year study was carried out in a rainproof mobile shelter to study the potential role of two cultivation practices (i.e., furrow with plastic mulching on ridges, RF; and conventional flat cultivation, TF) in combination with two deficit irrigation regimes (i.e., 150 and 75 mm) and three simulated rainfall (i.e., 1, 275 mm; 2, 200 mm; and 3, 125 mm). . We found that RF2150 treatment was more effective in improving the soil water content, soil respiration rate, and winter wheat production and significantly reduced (39.2%) the GHGI and GWP than TF2150 treatment. The RF2150 treatment improved soil moisture and significantly increased (18.9%) grain yield, (11.1%) biomass, (75.8%) WUEg, and (64.1%) WUEb of winter wheat and largely mitigated GWP and GHGI. The RF system with 150-mm deficit irrigation regime plays a significant role in increasing the biomass productivity and soil respiration rate and minimizing the seasonal greenhouse gas fluxes, GHGI, and field ET rates under 200-mm precipitation condition. Compared with TF practice, the plastic film mulching on ridges and furrow on the planting zone could significantly improve biomass and WUE and reduce N2O, CO2, and CH4 emissions. The RF2150 treatment should be very good water-saving approach and a powerful tool to decrease GHGI and GWP via increased biomass, WUE, soil respiration rate, and wheat yields under a dry-land farming system.