• 4 Agricultural education
• 4 Technical education
• 3 Agroforestry
• 3 Endangered ecosystems
• 3 Endangered species
• 3 Forestry schools and education
• 3 Forests and forestry
• 3 Horticulture
• 2 Conservation of natural resources
• 2 Environmental law
• 2 Environmental policy
• 2 Environmental protection
• 1 Agricultural implements
• 1 Agricultural machinery
• 1 Agriculture
• 1 Agronomy
• 1 Air
• 1 Biotic communities
• 1 Climatic changes
• 1 Ecological regions
• 1 Ecology
• 1 Farm equipment
• 1 Global warming

• 4 Infobase

• 2 English
• 1 Indonesian
• 1 Unknown

• 1 Asia

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