Effects of tillage practices on wheat production using groundwater-based irrigation: multidimensional analysis of energy use, greenhouse gases emissions and economic parameters.

Optimization of crop production inputs to reduce energy input and greenhouse gases emissions with maximizing economic productivity is needed to develop sustainable agriculture under groundwater-based irrigation conditions. This paper examined the effects of irrigated wheat tillage practices on energy indices, greenhouse gases emissions, and economic indices. Research treatments were conventional tillage and no-tillage (environment-friendly) systems in semi-arid environments. This study was conducted in wheat farms under groundwater-based irrigation, and data were monitored and collected for two years between 2012–2013 and 2013–2014. The results indicated that no-tillage practice had lower energy input (13%, 21.12 vs. 24.34 GJ ha⁻¹), energy output (18%, 83.01 vs. 101.11 GJ ha⁻¹), and energy use efficiency (7%), but higher energy productivity (19%) and indirect energy (9%) than conventional tillage practice. Moreover, no-tillage practice produced lower emissions of CO₂ (24%, 830.28 vs. 1096.40 kg ha⁻¹) and total global warming potential (GWP) (14%, 1830.03 vs. 2120.43 kg CO₂-equivalents ha⁻¹) than conventional tillage practice. In comparison, 53.9% of GWP originated from N₂O and 45.4% from CO₂. Inputs of electricity, diesel fuel, machinery, and nitrogen fertilizer had 95% contributions in emission from farms. Economically, no-tillage practice had higher productivity (3%, 7.06 vs. 6.86 kg US$⁻¹) but lower net return (18%, 1076.52 vs. 1313.48 US$ ha⁻¹) and benefit to cost ratio (14%, 3.10 vs. 3.61) than conventional tillage practice. However, producing wheat in this agroecosystem is profitable and beneficial under both tillage systems. It was concluded that the promising technique of the no-tillage under groundwater-based irrigation conditions significantly facilitated a cleaner production of wheat through managing energy with controlling greenhouse gases emissions in a semi-arid environment. [ABSTRACT FROM AUTHOR]