Nature Effect of human beings on 619 Human ecology 290 History 215 Religious aspects 154 Ecology 115 Environmental conditions 104 rhagor ... Environmental aspects 83 Social aspects 72 Philosophy 59 Environmentalism 58 Christianity 56 Environmental policy 55 Environmental degradation 54 Natural history 54 Climatic changes 51 Environmental protection 50 Human beings 48 Effect of environment on 45 Global environmental change 45 Nature conservation 36 Philosophy of nature 36 Psychological aspects 35 Pollution 31 Political aspects 30 Environmental ethics 29 Landscape changes 29 human ecology 27 Moral and ethical aspects 26 Human-animal relationships 25 llai ...