• 83 Environmental sciences
• 81 Water use
• 43 Land use
• 42 Water-supply
• 41 Earth sciences
• 41 Landforms
• 40 Geography
• 36 Power resources
• 32 Physical geography
• 17 Geology
• 16 Conservation of natural resources
• 14 Physical geology
• 12 Biotic communities
• 12 Ecological regions
• 11 Ecological zones
• 9 Environmental policy
• 9 Environmental protection
• 9 Technical education
• 8 Agricultural education
• 7 Environmental aspects
• 7 Government policy
• 7 Management
• 6 Agronomy
• 6 Earth (Planet)

• 129 Films Media Group
• 19 Films for the Humanities & Sciences (Firm)
• 17 PBS (Firm)
• 13 Camille S. DeBose (Firm)
• 13 Public Broadcasting Service (U.S.)
• 12 Green Planet Films (Firm)
• 8 Film Ideas (Firm)
• 6 BBC (Firm)
• 5 CINEFETE (Firm)
• 5 National Geographic Digital Media (Firm)
• 4 Bloomberg LP
• 4 Global Screen (Firm)
• 3 Australian Broadcasting Corporation (Firm)
• 3 Cerebellum Corporation (Firm)
• 3 Kwanza (Firm)
• 2 CNN (Firm)
• 2 Canadian Broadcasting Corp. (Firm)
• 2 MVD (Firm)
• 2 Magic Lantern Media Inc (Firm)
• 2 Network Ireland Television (Firm)
• 2 Prime Entertainment Group (Firm)
• 2 Video Education America (VEA) (Firm)
• 1 American Geosciences Institute (Firm)
• 1 Classroom Video (Firm)

• 128 English
• 1 Spanish

• 2 Asia
• 2 South Asia
• 1 Africa, Sub-Saharan
• 1 Brazil
• 1 California
• 1 Earth (Planet)
• 1 Europe
• 1 India
• 1 London (England)
• 1 North America
• 1 Portland (Or.)
• 1 Seoul (Korea)
• 1 United States

• 129 Internet videos
• 116 Video recordings for the hearing impaired
• 19 Educational films
• 19 Videorecording

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