1. Department of Sustainable Soils and Grassland Systems; Rothamsted Research; Harpenden Hertfordshire AL5 2JQ UK
2. Division of Agricultural and Environmental Sciences; University of Nottingham; Sutton Bonington Campus Loughborough Leicestershire LE12 5RD UK
3. Lancaster Environment Centre; Lancaster University; Lancaster LA1 4YQ UK
4. School of Energy, Environment and Agrifood; Cranfield University; Cranfield Bedfordshire MK43 0AL UK
5. Terrestrial Biogeochemistry Group; Institute of Bio- and Geosciences IBG-3: Agrosphere; Forschungszentrum Jülich GmbH; Jülich 52425 Germany
6. Phil Wallace Ltd; Westland; Martlesham Heath; Ipswich Suffolk IP5 3SU UK
7. University of Exeter; Amory Building Rennes Drive Exeter EX4 4RJ UK