Use of Biochar-Compost for Phosphorus Availability to Maize in a Concretionary Ferric Lixisol in Northern GHANA

Abstract

A pot experiment was conducted to investigate the effect of biochar-compost on availability of P for maize cultivation in a concretionary Lixisol of northern Ghana and residual soil characteristics thereof. Sawdust biochar was co-composted with kitchen waste and cow dung in various proportions. Four biochar-composts were selected based on their superior carbon and available P content, lower pH, and electrical conductivity (EC). These were amended to attain the standard phosphorus requirement (SPR) and half the SPR of the Lixisol. Triple superphosphate and (NH4)2 SO4 were, respectively, applied as inorganic fertilizer to meet the SPR and the average total nitrogen of the selected biochar-compost treatments. A control without any soil amendment was included. Maize was grown to tasseling (eight weeks) and shoot dry matter and P uptake determined. A 2.71 to 3.71-fold increase in P uptake led to a 1.51 to 2.33-fold increase in shoot dry matter in biochar-compost-amended soils over the control. Residual soil C, pH, and total and available P in the biochar-compost-amended soils were enhanced. Biochar-composts at half the SPR level produced maize with higher shoot dry matter than the equivalent inorganic amendment at full SPR.

Integrated Bioplant and Groundnut Husk Biochar Compost Application on Yield of Lettuce in a Rhodic Kandiustalf

“…The respective 2.1-fold and 3-fold increases in fresh and dry matter yields over the lettuce grown in the un-amended soil following the application of 40 parts of compost (C40) may be due to higher availability of N and P from the compost. The increase in lettuce biomass indicates an improvement in nutrient availability in the soils after the amendment of (C40) as found elsewhere by Sulemana et al (2021). This assertion is corroborated by the neutral pH, elevated total N, and available P contents in the residual levels of C40 treatments (Table 6).…”

“…The low clay content of the soil, which has been found to be dominated by low-activity clays like kaolinite (Eze, 2008), may, in part, explain the low CEC of 5.62 cmol(+)/kg. The moderately acidic pH of the soil in water coupled with the low organic carbon contents and the kaolinitic nature of the clay would promote low P availability (Nartey et al, 1997;Sulemana et al, 2021) as corroborated by the 5.96 mg/kg concentration. The poor fertility status of the soil justifies its choice and use as a medium for testing the efficacy of Bioplant.…”

“…The addition of compost to soil generally helps to improve the structure and fertility status of the soil. Additionally, amendment of the soil with the biochar-compost should increase the pH of the moderately acidic soils to near neutral to enhance P availability and dry matter yield (Latifah et al, 2018;Sulemana et al, 2021) as evident in the pH and available P content, especially of the residual C40 soils. The respective 2.1-fold and 3-fold increases in fresh and dry matter yields over the lettuce grown in the un-amended soil following the application of 40 parts of compost (C40) may be due to higher availability of N and P from the compost.…”

“…Compost, while supplying nutrients in the readily available form, increases the soil humus content to improve on the nutrient holding capacity (Dutta et al, 2003). Compost, being a buffer and alkaline can offset pH decreases arising from nitrification under aerobic soil conditions (Akumah et al, 2021;Sulemana et al, 2021). The amendment also improves on the general health or quality of the soil (Meena et al, 2016), by boosting the micro and macro flora and fauna population and activity (Ros et al, 2003) and organic carbon content (Sulemana et al, 2021) in the soil.…”

“…Compost, being a buffer and alkaline can offset pH decreases arising from nitrification under aerobic soil conditions (Akumah et al, 2021;Sulemana et al, 2021). The amendment also improves on the general health or quality of the soil (Meena et al, 2016), by boosting the micro and macro flora and fauna population and activity (Ros et al, 2003) and organic carbon content (Sulemana et al, 2021) in the soil. Composting could also be a way of closing the nutrient loop in circular photosynthesis by returning nutrient to the soil, thus minimizing nutrient mining.…”