Conservation Agriculture Research Updates - April 2026

This study looked at conventional (CT) and No-till (NT) in wheat/maize following puddled  or non-puddled TP rice or direct seeded rice. Also residue removal or retention. They looked at soil aggregation, carbon pools, nutrient availability and yield. After 6 years in top 20 cm soil, NT treatments had had more total organic carbon than CT treatments. NT treatments also had more stable soil aggregates. Retention of residues increased TOC,  and soil available nutrients, especially P, K and Zinc over residue removal. The conclude that NT with residue retention should be recommended for improving soil quality and production sustainability.

Soil degradation by soil organic carbon loss is a major concern in SSA. This study assesses the long-term (13 years) changes in SOC, aggregate associated C, particulate organic C (POC) and infiltration in sub-tropical, monocropping maize at 3 soil depths in South Africa. Tillage treatments were No-till (NT) and rotational tillage (RT) both with permanent residue cover and CT with residue removed. Nitrogen treatments were 0, 100 and 200 kg/ha. On average Total SOC did not differ between tillage treatments, but varied with depth where it was stratified in the 0-10 cm depth in NT and RT. POC varied and decreased significantly in the 0-10 cm depth with increased tillage intensity. They conclude that reduced soil disturbance improves physical protection of SOC, soil structure and infiltration but TSOC takes time to improve.