Soil Organic Carbon, Cation Exchange Capacity, and Maize (Zea mays) Response to Biochar and Nitrogen Fertilizer Amendments

Biochar, a rich carbon source, has a significant effect in increasing soil fertility and soil chemical properties. The experiment was carried out to study the effects of biochar and nitrogen fertilizer on soil organic carbon (OC), cation exchange capacity (CEC), and maize performance. The trial was a 3 × 4 factorial experiment arranged in a Randomized Complete Block Design (RCBD) with three levels of biochar (0, 2.5, and 5 t/ha) and four levels of urea fertilizer (0, 40, 80, 120 kg N / ha) replicated three times. Data collected were analyzed using the General Linear Model SAS software at p≤0.05. Means were separated using the Duncan Multiple Range Test (DMRT). Study results showed that the application of biochar significantly increased CEC but did not alter OC significantly. Biochar application had no effect on plant height, stover, and grain yield of maize. Nitrogen fertilizer application however had a significant effect on plant height, stover, and grain yield of maize. 5 tons of biochar with 120 kg of N fertilizer are therefore recommended for farmers in Minna to have an appreciable grain yield of maize. However, higher rates of biochar application should be investigated to better understand the potential effect of biochar on soil properties and plant characteristics.