Sustainability assessment of crop production in accord with energy, environment and economic performances in Nepal

Abstract

Increasing crop production usually warrants increased use of energy in the system that triggers the question of locating an ‘appropriate’ operating point by weighing the economics of output and its environmental impacts. Sustainability of diverse cereals, legumes and vegetable production systems were assessed in lowlands of Nepal in light of the efficiency of energy use, CO₂e (carbon dioxide equivalent) emissions and financial return–cost ratios. The energy saving potential of 238 farms selected in the study area is calculated adopting Data Envelopment Analysis (DEA). Based on the per-hectare energy consumption, vegetables (12.37 GJ), cereals (10.60 GJ) and legumes (3.80 GJ) crop production systems are ranked in descending order. Rice offered the highest per-hectare energy output (68.99 GJ) among the selected crops. Potential saving of energy inputs in the study area is shown to be between 18 and 35% without conceding yield of the particular crop production system. The highest environmental impact is due to garlic production (2997.13 kg CO₂e ha⁻¹); while rice, maize, wheat, lentil, mungbean and onion crops emit 60, 63, 28, 5, 3 and 86% CO₂e emissions (of that of garlic crop), respectively. As expected, the vegetable production remains the most profitable system with the return–cost ratio of 2.96–3.52, followed by legume (1.83–2.16) and cereal (1.21–1.96) production systems.