Location: Soil and Water Management ResearchTitle: Biochar effects on crop yield Author
Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 6/1/2014
Publication Date: 2/20/2015
Citation: Jeffery, S., Abalos, D., Spokas, K.A., Verheijen, F. 2015. Biochar effects on crop yield. In: Lehmann, J., Joseph, S., editors. Biochar for Environmental Management: Science, Technology and Implementation. New York, NY: Taylor & Francis. p. 301-326. Interpretive Summary:
Technical Abstract: From a strictly agronomic point of view, the potential benefit of biochar application must be considered as a consequence of its effect on enhancing soil productivity, which is determined by the entire spectrum of soil properties. Among these properties are: physical attributes, such as the size and continuity (and tortuosity) of pores, aggregate stability, and texture, which together determine soil structure; chemical properties, such as organic matter content and composition, nutrient stocks and availability, mineralogy, pH, salinity, and the quantity of elements and compounds that are deleterious to plant growth; biological attributes, such as the quantity, activity, and diversity of microbial biomass and soil fauna (Cassman, 1999). To be of use in agriculture, and before policy can be developed in detail, biochar application must show direct and/or indirect improvements on certain key soil properties without impoverishing the others. Verification of the effects and mechanisms by which biochar affects crop yields would, therefore, demonstrate the potential for biochar to help or hinder achieving global food security while concurrently aiding with the mitigation of climate change. In this chapter provide an overview of the history and review the potential of biochar use to increase crop productivity. After briefly showing the first agronomic application of biochar by Amerindian populations before the arrival of Europeans, we perform a quantitative meta-analysis of current studies reporting the effect of biochar on crop productivity and discuss the main mechanisms behind the effects. This data is then used to provide a framework for developing a biochar decision aid to facilitate decision making as to which biochar type should be best applied to a given soil/crop/climate.