Environmental impact Natural Resource Economics, (New March 2000) 19 Pollution and Degradation 19 Environmental aspects 17 Sustainability 15 Tourism and Travel 15 Leisure, Recreation and Tourism Economics, (New March 2000) 13 more ... Management 12 Policy and Planning 12 Pollution 12 Meteorology and Climate 11 Social Psychology and Social Anthropology, (New March 2000) 11 Economic impact 10 Agricultural Economics 9 Case studies 9 Land Resources 8 Tourism 8 Water Resources 8 Aquatic Biology and Ecology 7 Environmental protection 7 Plants 7 Risk assessment 7 Social impact 7 Animal Genetics and Breeding, (New March 2000) 6 Biological Resources (General) 6 Ecotourism 6 Feeds 6 Methodology 6 Techniques and Methodology 6 Agriculture 5 less ...