SUBJECT
Soil conservation
Soil erosion
22
Water conservation
18
Economic aspects
14
Social aspects
10
Upland conservation
7
Agroforestry
5
Soils
5
Erosion
4
Watershed management
4
Agricultural engineering
3
Hydraulic engineering
3
Sustainable agriculture
3
Agriculture and state
2
Contour farming
2
Environmental aspects
2
Government policy
2
Research
2
Soil productivity
2
Study and teaching
2
Afforestation
1
Agricultural conservation
1
Agricultural ecology
1
Agricultural productivity
1
Agricultural research
1
Agriculture
1
Agrobiodiversity conservation
1
Agroforestry -- Handbooks, manuals, etc
1
Biological diversity conservation
1
Climatic factors
1
Congresses
1
Conservation of natural resources
1
Corn
1
Economic conditions
1
Farmers
1
Forest influences
1
Hill farming
1
Hillside planting
1
Influence on nature
1
Land capability for agriculture
1
Land use
1
Man
1
Management
1
National parks and reserves
1
Planting
1
Plowing
1
Pollution
1
Rice
1
Social conditions
1
Soil conservation projects
1
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