RESEARCH ACTION NETWORK FOR REDUCING REACTIVE NITROGEN LOSSES FROM AGRICULTURAL ECOSYSTEMS

Project Information

ACTIONr

Grant agreement ID: 101079299

DOI

10.3030/101079299

Project closed

EC signature date 13 July 2022

Start date 1 November 2022

End date 31 October 2025

Funded under

• Widening participation and spreading excellence

Total cost

€ 1 506 658,73

EU contribution

€ 1 480 300,00

Coordinated by

PANEPISTIMIO THESSALIAS
Greece

Periodic Reporting for period 1 - ACTIONr (RESEARCH ACTION NETWORK FOR REDUCING REACTIVE NITROGEN LOSSES FROM AGRICULTURAL ECOSYSTEMS)

Reporting period: 2022-11-01 to 2025-10-31

Summary of the context and overall objectives of the project

The EU-funded ACTIONr project addressed the critical challenge of nitrogen (N) management in agriculture, recognising its essential role in food production and its contribution to environmental degradation when nitrogen is used inefficiently. Traditional farming practices relying on synthetic nitrogen fertilizers have led to nitrogen losses, environmental impacts and pressure on soil microbial communities. With a focus on Thessaly, a major agricultural region in Greece, ACTIONr aimed to improve nitrogen use efficiency (NUE) and mitigate environmental impacts linked to soil nitrogen cycling.
The main objectives of ACTIONr were to: (1) explore the cellular mechanisms of action of synthetic and biological nitrification inhibitors (NIs); (2) develop synthetic microbial communities to screen NI activity under ecologically relevant conditions; (3) assess the impacts of NIs on soil microbiota and greenhouse gas emissions; and (4) generate experimental evidence supporting the development of safer and more efficient NI-based fertilisation strategies. These objectives were addressed through close collaboration between the University of Thessaly (UTH), the Centre National de la Recherche Scientifique (CNRS; former École Centrale de Lyon group) and the University of Vienna (UNIVIE), combining complementary expertise in microbial nitrogen cycling.
Implemented as a Horizon Europe Twinning project, ACTIONr strengthened the scientific capacity and international integration of UTH through staff exchanges, advanced training activities and joint research. The project introduced advanced experimental and analytical approaches that were not previously available at UTH, including multi-omics workflows, synthetic microbial communities for nitrifier research, fast-track screening assays for nitrification inhibitors, and miniaturised soil microcosm systems enabling realistic assessment of microbial and nitrogen-cycle responses. These capacities are now embedded in the research activities of UTH and support ongoing and follow-up projects.
At the scientific level, ACTIONr advanced understanding of how synthetic and biological nitrification inhibitors interact with key microbial groups involved in nitrogen cycling at cellular, community and soil scales. At the institutional level, the project improved the international visibility of UTH, strengthened its participation in European research networks and competitive funding schemes, supported the development of a sustainable project portfolio, and established durable collaboration structures with its twinning partners, including a Joint PhD Platform. In line with global sustainability priorities, ACTIONr contributed to promoting responsible nitrogen use and environmental stewardship, consistent with the United Nations Sustainable Development Goals.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

Within the framework of the Twinning action, ACTIONr implemented a coordinated set of scientific and technical activities aimed at strengthening research capacity, methodological expertise and scientific competence in microbial Ν cycling at the University of Thessaly (UTH). The work was embedded in training-through-research, staff exchanges and joint experimentation, ensuring that capacity building remained central to the action. Scientific activities focused on elucidating how key microbial groups involved in nitrification respond to synthetic and biological nitrification inhibitors (NIs), while transferring advanced experimental and analytical methodologies to UTH researchers. Experimental work on ammonia-oxidizing archaea and bacteria in controlled laboratory systems generated mechanistic insights into NI–microbe interactions across cellular, community and soil levels. ACTIONr introduced and consolidated advanced methodological capabilities at UTH, including transcriptomics, proteomics, comparative genomics, stable isotope probing, and a fast-track screening system for rapid assessment of nitrification inhibitor activity. To enhance ecological relevance, synthetic microbial communities and soil microcosm experiments were developed, including validated miniaturised soil microcosm systems that enable efficient and realistic assessment of microbial activity and nitrogen cycling processes. These platforms now form part of the permanent experimental toolkit available at UTH. The main achievements of ACTIONr include strengthened scientific competence at UTH, successful local implementation of advanced experimental methodologies, and the generation of high-quality datasets supporting ongoing research and training. Overall, the project delivered durable technical and scientific outcomes that enhanced UTH’s capacity to conduct competitive research in microbial Ν cycling and to participate effectively in future European research and innovation initiatives.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The results of ACTIONr go beyond the state of the art by strengthening the capacity of the University of Thessaly (UTH) to investigate N cycling processes using integrated, multi-scale and methodologically advanced approaches that were not previously available. The project expanded the scientific basis for studying how N transformations are regulated by soil microorganisms and how they respond to synthetic and biological nitrification inhibitors. Through the combined use of multi-omics analyses, fast-track screening assays, synthetic microbial communities and soil microcosm systems, ACTIONr enabled the investigation of nitrification inhibitor effects across cellular, community and soil levels within a coherent experimental framework. This integrated approach represents an advancement in methodological depth and ecological relevance, particularly in the context of capacity building at a widening institution. While no product development or large-scale demonstration was pursued, the methodological platforms and datasets generated provide a strong foundation for follow-up research, pilot studies and future collaboration with industrial and agricultural stakeholders. By the end of the project, ACTIONr delivered enhanced scientific competence at UTH, established experimental platforms for studying nitrification inhibitors at multiple organisational levels, generated high-quality datasets, and created solid international collaboration structures, positioning UTH for more competitive participation in future European research and innovation initiatives.

The Nr cycle in agroecosystems and NUE improving strategies

ACTIONr infographic

Workflow-Schematic Pipeline of ACTIONr