Biochar in conservation farming in Zambia. Improving crop yield and storing carbon. Progress report February 2011
The main aim of the project is to investigate the potential of organic waste biochar to sequester carbon and improve the quality of weathered, sandy and/or acidic Zambian soils. Biochar amendment is exclusively combined with Conservation Farming (CF). In CF only 10-12% of the land is tilled. Therefore the expectation is that CF and biochar are a favourable combination, since less biochar is needed to obtain the same effectiveness as with conventional tillage. Chemical characterization of the soil-biochar combinations indicated that biochar could significantly improve the cation exchange capacities and decrease acid saturation of especially poor soils. Field tests were established at six sites. Halfway through the growth season the main conclusion was that biochar can strongly improve maize growth, especially for poor, low-nutirent soils and at low fertilizer rates. In high-quality soils biochar showed less or no effect.