Tillage, No-till, and Climate-smart Farming: A Critical Review of Long-term Sustainability Outcomes

Abstract

Tillage management lies at the heart of debates about sustainable agriculture, soil health, and climate change mitigation. As global interest in conservation agriculture and climate-smart farming intensifies, a rigorous reassessment of the long-term sustainability outcomes of tillage and no-till systems has become essential. This article presents a critical narrative review of the peer-reviewed literature on the agronomic, environmental, and socioeconomic dimensions of conventional tillage, no-till, and conservation agriculture, considered within the emerging framework of climate-smart agriculture. The evidence reveals a nuanced picture: no-till management offers meaningful benefits for soil physical properties, aggregate stability, water conservation, and reduced fuel emissions, but its role as a net greenhouse gas mitigation strategy is more limited and context-dependent than commonly assumed. While no-till often concentrates soil organic carbon in surface horizons, evidence for consistent deep-profile gains remains contested. Nitrous oxide emissions show mixed patterns that are strongly influenced by climate, soil drainage, and duration of practice. Crop yield responses to no-till vary considerably by crop type, aridity, and companion management practices; the integration of cover cropping and diverse crop rotations substantially enhances performance. Adoption barriers remain considerable among resource-poor smallholder farmers, particularly in sub-Saharan Africa, where promised productivity gains have frequently fallen short of expectations. Climate-smart agriculture provides a useful policy lens for aligning tillage decisions with adaptation, mitigation, and food security objectives, but its implementation requires site-specific targeting rather than prescriptive adoption. This review calls for integrated, context-sensitive tillage strategies underpinned by long-term experimental evidence, robust life-cycle accounting, and participatory approaches that respect the constraints of diverse farming communities.