Fertilizer technologies for reduced N2O emission from food production

The project will explore options to minimize N2O emissions from food production, be it by development of new fertilizer formulations/fertilizer regimes or alternative soil managements. The search for such mitigations in the past have largely been unsucces sful, but recent progress in molecular biology and our understanding of the microbial genetics and physiology which control N2O emissions have enhanced our possibilities greatly. Our point of departure is to study gas kinetics and gene expression in isola ted bacterial strains, soil bacterial communities and microcosms (soil slurries and intact soils). This explorative phase will provide - a better understanding of how N2O emissions are controlled by the regulatory biology (of denitrification) as realized within the soil matrix. - hypotheses regarding fertilizer formulations and management options which may effectively reduce the N2O emission from food production. The most promising options will be tested by upscaling to the field level flux measurement s. Ongoing research has already identified soil pH management as one promising option, and this will be tested early in the project period. The project will also measure N2O emissions from natural and agronomic ecosystems as an integral part of more comp rehensive investigation of the whole nitrogen cycling within the systems. The outcome of these studies are assessments of the overall N2O/N2 product ratios of whole systems. The project draws heavily on recent progress in molecular biological methods and novel gas kinetic methodology, and the complementary expertise in the project team consisting of the fertilizer company Yara and four leading research groups in China. Yara has taken a lead internationally in the development of precision fertilization, an d the current project represents an extension of these endeavors.