History 151 Economics 131 Agriculture 112 Land use 86 Land tenure 77 Land reform 66 Politics and government 65 Environmental economics-- Land economics 63 Rural development 60 Land economics 52 Tribes 50 Agricultural economics 49 India 47 Population 44 Land reforms 43 Scheduled tribes 42 Education 40 Industries 38 Communication 37 Finance 37 Wildlife management 37 Language and literature 36 Non-governmental organizations 36 Transportation 36 Untouchables 36 Urbanization 36 Tourist trade 35 Geography 34 Land 33 Social Sciences 32