Effects of crops residues management systems on crops yields and chemical characteristics of tropical ferruginous soil in Western Burkina Faso

Crop residues' inappropriate management is the main constraint causing the decline in soil fertility and crop yields in Burkina Faso. This study was conducted at the Farako-Bâ Research Station from 2014 to 2019 to assess the effects of crop residue management to improve the sustainability of the cotton-cereal based production systems. The experimental design was complete randomized blocks of Fischer with four replications. Three different crop residue management practices were investigated: (i) Crop residue exportation and conventional tillage (T1); ii) Composted crop residues and conventional tillage (T2); and (iii) Crop residues used for soil mulching and no-tillage (T3). Soil chemical characteristics and crop yields were assessed as parameters in this study. Crop yields were improved by 17 to 34% on maize, from 18 to 38% on cotton and from 6 to 14% on sorghum, respectively, with residues recycled into compost (T2) and residues used for soil mulching (T3) compared to residues exported (T1). Crop residue management and soil tillage technics significantly increased the yields of maize, sorghum, and cotton after the first three years of experimentation. Soil chemical properties were not statistically influenced, except for SOM, nitrogen, and available K content. The highest decrease in soil carbon content induced by crop residue exportation (T1) should not be recommended to farmers.