Human ecology History 523 Nature 446 Effect of human beings on 389 Environmental conditions 267 Religious aspects 227 Social aspects 213 mer ... Philosophy 209 Environmental policy 174 Environmental aspects 162 Environmental protection 156 Ecology 145 Human beings 128 Christianity 115 Climatic changes 106 Environmental ethics 105 Social conditions 105 Sustainable development 100 Effect of environment on 97 Environmentalism 96 Philosophy of nature 95 Environmental degradation 92 Conservation of natural resources 73 Environmental sciences 71 Human geography 70 Antiquities 67 Natural history 65 Social ecology 64 Economic aspects 60 Social life and customs 58 mindre ...