Human ecology 9 Environmental aspects 6 Environmental policy -- 6 Deforestation -- 4 Ecology 3 Ecology -- 3 Economic conditions 3 more ... Economic development -- 3 Environmental protection -- 3 Forest ecology -- 3 Human ecology -- 3 Developing countries 2 Economic conditions -- 2 Economic policy -- 2 Environmental aspects -- 2 Environmental policy 2 Forest conservation -- 2 History 2 History -- 2 International economic relations 2 Natural resources -- 2 Political aspects 2 Political aspects -- 2 Rain forest conservation -- 2 Rain forests 2 Rain forests -- 2 Social sciences 2 Sustainable development -- 2 Tropics 2 Agriculture -- 1 less ...