No abstract

This study investigated the effect of biochar amendments on the retention and availability of plant nutrients and Al in seven acidic tropical soils from Zambia and Indonesia. The experiments carried out investigated whether the adsorption capacity of NH þ 4 in the soils increased upon the addition of biochar and which effect biochar had on available concentrations of NO À 3 , K + , Mn 2+ , Mg 2+ , PO 3À 4 , and Al 3+ . These nutrients were selected as they represent those important to plant growth and soil quality. No significant increases or decreases in aqueous NH 4 to the soil-biochar mixtures as compared to the soil alone. However, the addition of biochar to the soil from Zambia increased the sorption of PO 3À 4 compared to the soil alone. The concentrations of K + and Mg 2+ were significantly increased for almost all soils (t-test at the 0.05 confidence level) following the addition of biochar. Addition of biochar to all but two soils significantly decreased (t-test confidence level 0.05) Mn 2+ concentrations. The concentration of Al 3+ in the soils decreased exponentially significantly (t-test confidence level 0.05) following the amendment of biochar in accordance with the increase in pH observed when biochar was added to the soil. These results show that biochar has the ability to release essential plant growth nutrients as well as alleviate Al toxicity in these soils.

No abstract

No abstract