Impacts of adding biochar on nitrogen retention and bioavailability in agricultural soil

• Published in: Geoderma Vol. 206; pp. 32 - 39
• Main Authors: Zheng, Hao, Wang, Zhenyu, Deng, Xia, Herbert, Stephen, Xing, Baoshan
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.09.2013; Elsevier
• Subjects: adsorption; agricultural soils; Agronomy. Soil science and plant productions; Bioavailability; Biochar; Biological and medical sciences; corn; Crop growth; Earth sciences; Earth, ocean, space; Exact sciences and technology; Fertilizing; Fundamental and applied biological sciences. Psychology; Grounds; Leaching; Maize; nitrogen; Nitrogen (N); nitrogen fertilizers; Productivity; Retention; Soil (material); soil productivity; soil water; Soils; Surficial geology; water holding capacity; Zea mays; Bioavailability; Nitrogen (N); Biochar; Retention; Leaching; Nitrogen fertilization; Monocotyledones; ammonium; Immobilization; nitrates; Carbonization; Amendment; productivity; Gramineae; Angiospermae; soils; Nitrogen fertilizer; retention; Plant production; adsorption; Zea mays; soil moisture; accumulation; nitrogen; Nutrient recovery; Agricultural soil; leaching; Spermatophyta; growth; Water holding capacity
• ISSN: 0016-7061; 1872-6259
• DOI: 10.1016/j.geoderma.2013.04.018

Interest in the use of biochar to improve soil productivity has rapidly increased. Nitrogen (N) loss, retention and bioavailability in biochar-amended soils fertilized with NH4+–N and NO3−–N were studied using leaching and pot experiments. NO3−–N leaching from the soils fertilized with NH4+–N and NO3−–N was significantly reduced by biochar addition. NH4+–N leaching from the NO3−–N fertilized soil was also significantly reduced by biochar, while no significant effect was observed for the NH4+–N fertilized soil. Also lower NH4+–N and NO3−–N were leached from NO3−–N fertilized soil with maize (Zea mays L.) grown. Mitigation of N leaching loss following biochar addition is mainly attributed to the increase in soil water holding capacity (WHC), NH4+ adsorption and enhanced N immobilization. Biochar addition stimulated maize growth, both above and below ground. Biochar also increased N utilization efficiency (NUE) of maize but decreased N accumulation efficiency (NAE), indicating that biochar addition may improve N bioavailability in agricultural soils. Therefore, reduction of N leaching, and increase of N retention and bioavailability in agricultural soils can potentially decrease the N fertilizer demand for crop growth. •Biochar reduced NO3−–N and/or NH4+–N leaching from soils.•Biochar addition improved maize growth including biomass and root morphology.•Biochar increased N utilization efficiency, but reduced N accumulation efficiency.•Biochar could increase N retention and bioavailability in agricultural soils.