Effects of biochar fertilizers and soil type on yield trends and soil fertility in cotton-maize systems in western Burkina Faso

Effets de la fertilisation à base de biochar sur les paramètres agropédologiques à l’ouest du Burkina Faso

Abstract

In Burkina Faso, low soil fertility combined with low nutrient returns from crop exports are responsible of the declining agricultural production. Fertilizers derived from activated biochar (biochar-SRF), a by-product of cotton stalk pyrolysis, were compared to microdosing of mineral fertilizer of NPK and urea and farmers practice which combined 2,5 t of compost to recommended rate of NPK and urea in a field experiment in western Burkina Faso. A randomized block design was established during three seasons on the farms of two farmers in a cotton-corn rotation. Each farmer represented a soil type. Comparative treatments included: conventional practice (T1), microdosing (T2) and biochar-SRF (T3), each replicated four times. Treatments' performance was assessed on agronomic and soil parameters (plants growth, yield, soil exchangeable capacity, pH, N, P, K). The highest plant growth rates and crops yield were observed with biochar-SRF and microdose treatments. Beneficial effects of the biochar-SRF fertilizer were observed on soil parameters such as soil exchangeable capacity, organic matter, and pH, impacting positively on overall soil fertility, with a pronounced effect on ferruginous concretions soil. This suggests that biochar-based fertilization can be promoted as a sustainable alternative to conventional practice.