Towards greater nitrogen use efficiency in agroecosystems
Agriculture uses over 120 x 106 metric tons of nitrogen (N) fertilizer p.a. globally, but more than 50 % of the applied N is lost to the environment. This unsustainable practice is accompanied with low nutrient use efficiencies (NUE) and serious environmental problems i.e. nitrite pollution. Therefore new ways are needed to effectively target the efficient use of N.
Soil microbes are key to N cycling; they can influence N – flows and pathways, and dictate the amount of N available to plants or lost. To date, a plethora of field observations on N and crop yields have been collected; unfortunately our current understanding has failed neither to reduce N loss nor to improve NUE. Agroecosystem models assume that soil microbes are somehow inflexible. However, emerging evidence suggests that soil microbes can regulate NUE for example in relation to varied N availability.
Therefore by deciphering the microbial component, a more comprehensive understanding of the controls and factors regulating the N cycling in agroecosystems will put forward new ways and approaches to enhance the NUE in agroecosystems.
The diversity of N cycling processes in agricultural soils will be investigated in a series of lab and field experiments, combining classical and state-of-the-art microbiological, biochemical and molecular techniques at high temporal resolution. This will allow us:
- to quantify the relationships among the microbial activity, the environment and the (highly variable) efficiency with which N – fertilizers are used,
- to decipher the intrinsic link between microbial N regulation and crop uptake in intensified agroecosystems, and
- to quantify the pathways which nitrogen is lost to
the environment.
The proposed research is designed to have a two-fold impact:
- to resolve the temporal dynamics of N cycling in agricultural soils, and
- to suggest new ways to optimize the use of N fertilizer, to reduce costs, and to improve yields.
Nitro-Ag is organized in 5 work packages (WP)
- Deciphering the factors and controls of N cycling in agricultural fields (WP1 Field Study)
- Mechanistic understanding of the factors and controls regulating N cycling ecology and biochemistry (WP2 Mesocosm studies)
- Plot study (WP3 Plot/Field study)
- Results synthesis and dissemination (WP4 Publications & dissemination)
- Project Management (WP5 Administrative & scheduling)
Nitro-Ag is expected to complete in June 2024 (36 months). Nitro-Ag is a personal research grant awarded to Dr Georgios Giannopoulos (PI) for postdoctoral research in the field of Agricultural Sciences under the 2nd call for postdoctoral research by the Hellenic Foundation for Research and Innovation under the General Secretariat for Research and Technology.
