The combined application of nitrogen and biochar reduced microbial carbon limitation in irrigated soils of West African urban horticulture

Urban Farm DB summary

This 2-year study in semi-arid Ouagadougou and sub-humid Tamale, West Africa, measured the effects of biochar and N fertilization on soil microbial biomass carbon, fungal ergosterol, and functional diversity. Sole biochar addition did not affect soil chemical or biological properties, but biochar with N fertilization increased microbial respiratory response. N fertilization decreased soil pH by 1.1 units in both cities, and a pH of 4.7 led to reduced microbial biomass carbon and ergosterol contents in Tamale. An N fertilizer-induced decline in soil pH below 5 should be avoided, as it decreased microbial biomass carbon and microbial functional diversity.