Land management 10 Land Resources 8 Sustainability 6 Land use 4 Natural Resource Economics, (New March 2000) 4 Pollution and Degradation 4 Social Psychology and Social Anthropology, (New March 2000) 4 more ... Biological Resources (General) 3 Case studies 3 Silviculture and Forest Management 3 Soil Fertility 3 Soil fertility 3 Agroforestry 2 Agroforestry and Multipurpose Trees: Community, Farm and Social Forestry 2 Agroforestry systems 2 Biodiversity 2 Conflict 2 Cropping systems 2 Environmental degradation 2 Field Crops, (New March 2000) 2 Forest management 2 Forests 2 Forests and Forest Trees (Biology and Ecology) 2 Land degradation 2 Nature conservation 2 Plant Cropping Systems 2 Policy and Planning 2 Productivity 2 Soil Chemistry and Mineralogy 2 Tropics 2 less ...