2010/11/23 by A. Silber, I. Levkovitch, Ellen R. Gräber · 5 citations
Materials Science · Agricultural and Biological Sciences · Environmental Science · Chemistry · #Clay minerals and soil interactions #Soil Carbon and Nitrogen Dynamics #Phosphorus and nutrient management #Biochar #Chemistry #Cation-exchange capacity #Fertilizer #Soil water #Organic matter #Dissolution #Environmental chemistry #Soil pH #Nutrient #Soil fertility #Ion exchange #Ion #Soil science #Pyrolysis #Environmental science
paper · doi:10.1021/es101283d
openalex publication_date 2010/11/23 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/29
Surface charge and pH-dependent nutrient release properties of cornstraw biochar were examined to elucidate its potential agronomic benefits. Kinetics of element release was characterized by rapid H(+) consumption and rapid, pH-dependent P, Ca, and Mg release, followed by zero-order H(+) consumption and mineral dissolution reactions. Initial K release was not pH-dependent, nor was it followed by a zero-order reaction at any pH. Rapid and constant rate P releases were significant, having the potential to substitute substantial proportions of P fertilizer. K releases were also significant and may replace conventional K fertilizers, however, not long-term plant demand. The cation exchange capacity (CEC) of the biochar leached with a mild acidic solution increased linearly from 179 to 888 mmol(c) (kg C)(-1) over a pH range of 4-8, while the anion exchange capacity of 154 mmol(c) (kg C)(-1) was constant over the same pH range. Since native soil organic constituents have much higher CEC values (average 2800 mmol(c) (kg C)(-1) at pH 7), improved soil fertility as a result of enhanced cation retention by the biochar probably will be favorable only in sandy and low organic matter soils, unless surface oxidation during aging significantly increases its CEC.