1. School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, England
2. School of Geography and the Environment, University of Oxford, South Parks Road, Oxford OX1 3QY, England
3. Institut de Géographie, Faculté des Géosciences et de l'Environnement, Université de Lausanne, Lausanne CH 1015, Switzerland
4. School of Geographical Sciences, University of Bristol, University Road, Bristol BS8 1SS, England
5. Faculty of Social Sciences, University of East Anglia, Norwich NR4 7TJ, England
6. Centre for Rural Economy, School of Agriculture, Food and Rural Development, Newcastle University, Newcastle upon Tyne NE1 7RU, England