Soil Carbon Restoration through Conservation Agriculture

Abstract

Poor soil fertility and soil degradation induced by persistent conventional farming with repeated tillage and removal or in situ burning of crop residue are major limitations to food security and environmental sustainability. However, degraded agricultural lands with depleted soil organic carbon (SOC) stocks are capable of soil carbon restoration through improved management practices like aggregation, humification and deep placement of C that can increase SOC seques-tration. According to FAO, conservation agriculture (CA) is arrived at as a solution to restore SOC with three pillars of minimum soil disturbance, permanent organic soil cover and diversified crop rotations. A significant increase in SOC levels under zero tillage (ZT) over conventional tillage (CT) was found; returning more crop residues to the soil is associated with an increase in SOC concentration that is further increased by crop diversification. Additionally, the incorporation of high-value trees with CA is treated as a working model for C storage. Thus, conservation agriculture is an operational approach to restore SOC that aggrades soil, reduces environmental footprints and makes agricultural systems more resilient to climate change.