In addition to the benefits that bi

In addition to the benefits that biochar offers by significantlyreducing soil contaminants through adsorption and/or sequestration of pesticides or their metabolites, biochar amendmentsalso have the potential to serve as soil conditioners by changingthe physicochemical and biological properties of soil, such asincreasing soil pH, cation exchange capacity (CEC) and soilbuffering (Lehmann and Joseph, 2009). Kimetu and Lehmann(2010) reported that the decrease in maize crop yields in theWestern Kenyan Highlands, which was due to the continuouscultivation over 100 years, increased by up to 70% when biocharamendment was utilized; this increase in yield may mainly beattributed to the improvement in the physical properties of soilsuch as pH and water holding capacity. Biochar-amended soilusually exhibits higher soil water contents and nutrientretention compared with unamended soil (Tang et al., 2013;Ahmad et al., 2014). Cui et al. (2014) observed a decrease inadsorption but an increase in desorption of phosphorous onferrihydrite in the biochar-amended soil. Uzoma et al. (2011)reported that maize grain yields significantly increased by 150%and 98% in the soil amended with cow manure biochar at 15 and20 tons/ha, respectively. This enhanced plant growth waspotentially related to improvements in soil properties andnutrient availability following the biochar amendment.Tammeorga et al. (2014) illustrated that the use of biocharas a soil amendment could improve soil poor water retentioncapacities and nutrient deficiencies that were the limitingfactors in subtropical and temperate soils. Wood biocharapplication at 3 and 6 tons/ha in sandy clay loam soil reduceddrought stress and consequently enhanced wheat yield, whichmay have been due to increased water availability .