Soil Conservation for Mitigation and Adaptation to a Changing Climate: Sustainable Solutions in the Nigerian Savanna Ecology

Abstract

Soil conservation and quality improvement under intensive land use and fast economic development has become a major challenge for sustainable natural resource use in developing countries such as Nigeria. Conventional tillage is commonly practiced at land preparation and effect of this on soil quality for sustainable productivity has been very discouraging. Therefore measures for mitigating soil degradation, adverse effects of climate change and encouraging adaptation/adoption under intensive agricultural land use were investigated in this study. Conservation Agriculture tillage-based practices with Nitrogen and Phosphorus fertilizer rates’ application were studied in a Nigerian Savanna Alfisol. Results show that Conservation Tillage practices involving in-situ grown, incorporated and relayed legumes like Centrosema pascuorum and Desmodium uncinatum ameliorated soil acidity, enhanced soil carbon sequestration, improved cation exchange capacity of the soil, and resulted in higher maize and sorghum grain yields than Conventional tillage and No-Till practices. Conservation tillage (C. pascuorum in-situ grown, incorporated and relayed) combined with 100 kgNha-1 and 26.4kgPha-1 resulted in higher maize grain yield that increased from 2.58 tha-1 in 2010 to 3.67 kgha-1 in 2011. Conservation tillage (Desmodium uncinatum in-situ grown, incorporated and relayed) combined with 50 kgNha-1 and 13.2 kgPha-1 resulted in 1.48 tha-1 sorghum grain yield that was significantly higher than the other tillage practices.