Human ecology 1,705 History 396 Nature 299 Effect of human beings on 255 Environmental conditions 221 Religious aspects 179 Ecology 177 more ... Social aspects 169 Philosophy 156 human ecology 152 Environmental aspects 139 Environmental policy 117 Human ecology in literature 105 Christianity 87 Environmental protection 86 Social conditions 82 Social ecology 81 Environmental ethics 80 Sustainable development 77 Human beings 76 Climatic changes 75 Philosophy of nature 74 Environmental degradation 71 Environmentalism 71 History and criticism 66 Social life and customs 64 Antiquities 61 Effect of environment on 60 Human geography 60 Ecocriticism 56 less ...