Water Use Efficiencies, Productivities, and Footprints of Rice under a System of Rice Intensification Practice

Adoption of a system of rice intensification (SRI) practice for rice production needs thorough investigation on the amount of water utilized in rice fields as water flow involves interaction of very complex processes, leading to different pathways of water losses. Hence, a field study was carried out during kharif and rabi seasons of 2015–16 and 2016–17, to investigate the effect of the SRI practice on water use efficiencies, productivities and water footprints. Two water treatment experiments (conventional and SRI) with six replications were laid out in the experimental plots. Nonweighing lysimeters, installed in neighboring plots were used to measure the water balance components under both water management practices. Results showed that the considerable reduction in water input (21% in kharif and 18% in rabi seasons) for the SRI cut the deep percolation drastically by 24–29% and 23% in kharif and rabi, respectively. There was no considerable reduction in evapotranspiration under the SRI with comparison to conventional practices. Grain yield was significantly increased by 23–30% and 20–29% under the SRI in kharif and rabi seasons, respectively. Hence, a significant (p < 0.05) fall in consumptive water footprint (19–26% in kharif and 18–24% in rabi) was achieved under the SRI. On average, the crop water use efficiency was enhanced by 25–26% and 19–20% in respective kharif and rabi under the SRI practice. Significant improvement in total water productivity by 56–66% and 46–56% in respective two seasons was also observed in the SRI during the two years of field experiments.