SUBJECT
Afforestation
1
Agricultural conservation
1
Agricultural ecology
1
Agricultural engineering
3
Agricultural productivity
1
Agricultural research
1
Agriculture
1
Agriculture and state
2
Agrobiodiversity conservation
1
Agroforestry
5
Agroforestry -- Handbooks, manuals, etc
1
Biological diversity conservation
1
Climatic factors
1
Congresses
1
Conservation of natural resources
1
Contour farming
2
Corn
1
Economic aspects
14
Economic conditions
1
Environmental aspects
2
Erosion
4
Farmers
1
Forest influences
1
Government policy
2
Hill farming
1
Hillside planting
1
Hydraulic engineering
3
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
Research
2
Rice
1
Social aspects
10
Social conditions
1
Soil conservation
Soil conservation projects
1
Soil degradation
1
Soil erosion
22
Soil erosion prediction
1
Soil productivity
2
Soils
5
Sols
1
Stories and anecdotes
1
Study and teaching
2
more ...