Use of charcoal (biochar) to enhance tropical soil fertility: A case of Masako in Democratic Republic of Congo

Soil fertility transience in the region of Masako in Democratic Republic (RD) of Congo remains a major challenge to sustainable agricultural production. Recently, biochar application as soil amendment has attracted attention of the people across the world owing to its potential to improve soil physicochemical properties, crop yield and carbon sequestration into the soil. A study was conducted in Masako to analyze the use of charcoal (biochar) as soil amendment and assess its effects on soil chemical performance and some biophysical parameters of maize crop. The experiment was set up using randomized complete block design with three replications of three treatments comprising ½ kg of sieved (small-sized particulate) charcoal per m2 (C1), 1 kg of sieved charcoal per m2 (C2) and control group without charcoal (C0). Data were subjected to analysis of variance, Pearson’s phenotypic correlation and regression analyses using genstat 12th edition. The results of the analysis of variance showed non-significant variation for most physicochemical properties of soil and maize phenotypic traits, indicating that treatments had the same effects on soil composition suggesting that there was no clear impact of charcoal amendment as applied except for phosphorus content and collar diameter of the maize crop which were significantly (P ≤ 0.047 and P ≤ 0.043 respectively) influenced by the treatments. The results indicated that biochar improved the soil phosphorus availability by up to 72% as accounted for by the linear contribution of the treatment C2 indicating that biochar could be recommended for use in soil with low level of phosphorous.