Can biochar improve soil physical properties of northern Ghana loamy sandy soils

Soils of the northern region of Ghana are largely coarse-texture and shallow as a consequence, their Water Holding Capacity (WHC) is low, with much of seasonal rainfall lost through drainage which is detrimental to crop growth. Given the poor state of the soil amendment application different experiments were carried in 2021 out to achieve two objectives, thus, the first experiment was a series of runoff and drainage (R+D) conducted in the laboratory to assess the effect of biochar application on (R+D). The second experiment was carried out to determine the effect of biochar applications on Available water capacity AWC, Field capacity (FC), Permanent wilting point (PWP) and bulk density BD. The relationship between biochar application rate and the physical properties was also derived as a function of clay ratio and Biochar application. Study soils used were sampled from 3 locations in the northern regions, namely Wa (Upper West), Tamale (Northern Region) and Navrongo (Upper East). The same soil was used for the two experiments. The results showed that biochar had significant effect on the FC but not on PWP. Biochar application increased the AWC of the soil such that AWC increased from 0.03 cm3/cm3 for BC0 for the soil from Tamale to 0.06 cm³/cm³ for B20. In general, BC10 and BC20 did not differ significantly. Biochar application also influenced the BD with the highest BC20 ton/ha decreasing the initial BD from 1.50 to 1.30 g/ cm3. Runoff + drainage decreased with biochar application in the farming area BC20 < BC10.The effectiveness of biochar on R+D, BD reduction, and AWC increased as the CR decreased (i.e., high CR = low clay).