Long-term use of cover crops and no-tillage in southern Brazil increases soil enzyme activity and carbon stock, benefiting rice cultivation. The study compared different cover crops and fertilization methods in an Entisol soil since 1996. Results showed that cover crops with no-tillage boosted soil respiration, enzyme activity, and carbon and nitrogen stocks. System fertilization led to higher grass productivity but less increase in legumes. Overall, the combination of cover crops and no-tillage improved rice yield by 9%, demonstrating the benefits of these conservation practices for soil health and crop productivity.