Applied ecology Development economics & emerging economies 24 Environmental policy & protocols 18 Environmental economics 4 Environmental science, engineering & technology 4 Agriculture & related industries 3 Alternative & renewable energy sources & technology 3 Environmental management 3 Mining industry 3 Central government policies 2 Food & society 2 Natural history 2 Politics & government 2 Business & management 1 Climate change 1 Energy 1 Environment law 1 Ethics & moral philosophy 1 Human geography 1 Industry & industrial studies 1 International relations 1 Sociology 1