Nature Effect of human beings on 659 Naturaleza 329 Human ecology 302 History 212 Religious aspects 168 Science 118 more ... Ecology 104 Environmental conditions 103 Natural resources 99 General 95 Recursos naturales 95 Environmental aspects 92 Agriculture 88 Social aspects 86 Technology 78 Tecnologia 71 Climatic changes 70 Documentary films 70 Agricultura 64 Ecosistemas y habitats, bosques y selva tropical 63 ecosystems and habitats 63 forests and rainforests 63 Philosophy 62 Christianity 60 Environmental degradation 60 Conservacion y proteccion del medio ambiente 58 Environmentalism 57 Forestal 56 Forestry 56 less ...