Energy resources Land resources 6 Renewable resources 6 Food resources 5 Forest resources 5 Mineral resources 4 Nuclear pollution 4 Radiation pollution 4 Wasteland reclamation 4 Water resources 4 Disaster management 3 Economics 3 Ecosystems 3 Marine pollution 3 Natural disasters 3 Natural resources 3 Non renewable resources 3 Climatic change 2 Environmental studies 2 Human population 2 Noise pollution 2 Nuclear power 2 Soil pollution 2 consumerism 2 disaster management 2 Acid rain 1 Air resources 1 Biomass burning 1 Biomass energy 1 Biomass gasification 1