Business Members
Organization Members

Sign Up For Email Updates

Enter your email address:

Follow us on Twitter
Follow us on Twitter
Follow IBI
Photo of Biochar
Biochar Certification
Help put the Earth back in the black

Plant growth improvement mediated by nitrate capture in cocomposted biochar

TitlePlant growth improvement mediated by nitrate capture in cocomposted biochar
Publication TypeMiscellaneous
Year of Publication2015
AuthorsKammann, Claudia I., Schmidt Hans-Peter, Messerschmidt Nicole, Linsel Sebastian, Müller Christoph, Koyro Hans-Werner, Conte Pellegrino, and Stephen Joseph

Soil amendment with pyrogenic carbon (biochar) is discussed as strategy to improve soil fertility to enable economic plus environmental benefits. In temperate soils, however, the use of pure biochar mostly has moderately-negative to positive yield effects. Here we demonstrate that co-composting consideably promoted biochars' positive effects, largely by nitrate (nutrient) capture and delivery. In a full-factorial growth study with Chenopodium quinoa, biomass yield increased up to 305% in a sandy-poor soil amended with 2% (w/w) co-composted biochar (BCcomp). Conversely, addtition of 2% (BCcomp) as well as growth-reducing (BCpure) effects were more pronounced at lower nutrient-supply levels. Electro-ultra filtration and sequential biochar-particle washing revealed that co-composted biochar was nutrient-enriched, particularly with the anions nitrate and phosphate. The captured nitrate in BCcomp was (1) only partly detectable with standard methods, (2) largely protected against leaching, (3) partly plant-available, and (4) did not stimulate N2O emissions. We hypothesize that surface ageing plus non-conventional ion-water bonding in micro- and nano-pores promoted nitrate capture in biochar particles. Amending (N-rich) bio-waste with biochar my enhance its agronomics value and reduce nutrient losses from bio-wastes and agricultural soils.