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Nitrous Oxide Emissions and Greenhouse Gas Balances during Storage and Field Application of Organic Fertilizers Produced from Cattle Manure

PhD defence, Tuesday 30 May 2023, Xiaoyi Meng

Photo: Xiaoyi Meng

During her PhD studies, Xiaoyi Meng studied the emissions of CH4, N2O, and NH3 during storage and after field application of different manure-derived fertilizers. The carbon footprint of different manure-derived fertilizers were compared by life cycle assessment. Lab experiment illustrated the mechanism of soil N2O emissions after manure application.

The new research findings highlights the environmental advantages of anaerobic digestion of manure and further separation of digestate. Soil N2O emissions are affected by soil water potential and gas diffusivity. The relationships between soil N2O emissions, soil type, and the composition of organic fertilizers are not straightforward. The intricate interactions between soil and fertilizer should be taken into account when developing strategies to reduce N2O emissions and overall GHG emissions in agricultural systems.

The PhD study was completed at Department of Agroecology, Faculty of Technical Sciences, Aarhus University.

This summary was prepared by the PhD student.

Time: Tuesday, 30 May 2023 at 12:00
Place: 8814-3075, Auditorium, AU Viborg, Aarhus University, Blichers Alle 20, 8830, Tjele

Title of PhD thesis: Nitrous Oxide Emissions and Greenhouse Gas Balances during Storage and Field Application of Organic Fertilizers Produced from Cattle Manure

Contact information: Xiaoyi Meng, e-mail: au657355@uni.au.dk, tel.: +45 91695543

Members of the assessment committee:

Professor David Chadwick, School of Natural Sciences, Bangor University, United Kingdom

Research Officer Patrick Forrestal, Crops, Environment and Land-Use Programme, TEAGASC, Ireland

Senior researcher Jim Rasmussen (chair), Department of Agroecology, Aarhus University, Denmark

Main supervisor:
Professor Søren O. Petersen, Department of Agroecology, Aarhus University, Denmark

Co-supervisor:
Senior researcher Marie Trydeman Knudsen, Department of Agroecology, Aarhus University, Denmark

Language: The PhD dissertation will be defended in English

The defence is public.
The PhD thesis is available for reading at the Graduate School of Technical Sciences/GSTS, Jens Baggesens Vej 53, build. 5221, 8200 Aarhus N.