No-till and mulching enhance energy use efficiency and reduce carbon footprint of a direct-seeded upland rice production system

Abstract

Sustainability of conventional agricultural production systems is threatened by triple challenges of energy and environmental crises, deteriorating natural resources bases, and declining farm profitability. Current agricultural management practices (energy-intensive, inefficient external and natural input use, and crop biomass burning) are negatively impacting the ecosystem services which are the principal drivers for food security and human survival. Hence, there is a need to shift from unsustainable production practices to cleaner production systems. Energy use, carbon footprint (CF), and economic sustainability are important indicators of any clean production systems. Thus, a hypothesis was formulated that no-till (NT) cultivation along with mulching can provide an environmentally clean crop production practice that can enhance energy use efficiency, economic profitability, and reduce the CF. Therefore, the present experiment was conducted for four consecutive years (2012–15) to evaluate the energy budget, CF, and economics of NT along with bio-mulching for a cleaner upland rice production system. The experiment comprised of two tillage practices i.e., conventional tillage (CT) and NT in main plots and four bio- mulches in subplots i.e., rice straw mulch (RSM), Gliricidia sepium mulch (GLM), brown manuring mulch (BMM) of cowpea (Vigna unguiculata), and no mulch (NM) as a control. Results revealed that the adoption of NT curtailed energy use by 48.50%, specific energy by 49.63%, CF by 16.48%, and cost of cultivation by 35% in addition to enhancing energy use efficiency and benefit to cost ratio in comparison to CT. It was also observed that mulching, particularly the BMM, boosted the energy use efficiency, economic productivity, net returns, and benefit to cost ratio over NM. The results suggested that NT with BMM is an environmentally clean production technology to enhance the energy use efficiency, besides reducing the CF of direct-seeded upland rice production system in the Eastern Himalayas and similar eco-regions of the world.