Conservation of natural resources Environmental policy 199 Natural resources 115 Environmental protection 110 Environmental management 94 Management 87 Ecology 86 more ... Medio ambiente 85 Administracion 83 Environmental aspects 81 Sustainable development 80 History 73 Human ecology 72 Recursos naturales 67 Nature conservation 56 Government policy 55 Effect of human beings on 53 Nature 53 Conservacion 48 Politica medioambiental 46 Wildlife conservation 45 Biodiversity conservation 38 Climatic changes 38 Politica ambiental 37 Citizen participation 36 Law and legislation 36 Economic aspects 34 Environmental conditions 30 Renewable energy sources 28 Sustainable agriculture 27 less ...