Effects of biochar or activated carbon on soil nutrients and its availability

Abstract

The impact of biochar (2% and 10% on dry weight basis) or activated carbon amendment (2% on dry weight basis) on the sorption and availability of nitrate, ammonium and phosphate in different type of soils was investigated. Biochar amendments increased the total nitrogen, total phosphorus, soil salinity and pH depend on the biochar application rate and soil properties. However, the availability of nitrate, ammonium and phosphate in soil with or without biochar (2% and 10%) were decreased with increasing prior contact period between soil and biochar and with an increasing biochar application rate, due to sorption of ammonium and nitrate by biochar. Furthermore, the available nitrogen form shifted towards ammonium in biochar amended soils, although nitrate mostly remained predominant.