• 637 Videos, Slides, Films

• 161 Ecological regions
• 156 Pollution
• 149 Biotic communities
• 130 Conservation of natural resources
• 121 Environmental protection
• 120 Environmental policy
• 119 Biodiversity
• 114 Environmental law
• 105 Air
• 105 Climatic changes
• 103 Ecology
• 100 Global warming
• 95 Biology
• 95 Natural resources
• 85 Life sciences
• 67 Ecological zones
• 62 Study and teaching
• 58 Water
• 54 Water use
• 48 Toxicology
• 47 Land use
• 44 Water-supply
• 40 Endangered ecosystems
• 40 Endangered species

• 562 Infobase
• 92 PBS (Firm)
• 74 Films for the Humanities & Sciences (Firm)
• 42 BBC (Firm)
• 38 Green Planet Films (Firm)
• 30 Film Ideas (Firm)
• 28 BBC Worldwide Learning (Firm)
• 26 Media Policy Center (Firm)
• 15 CNN (Firm)
• 15 TV Only SAS (Firm)
• 14 Green Interview (Firm)
• 13 Annenberg Learner (Firm)
• 12 Australian Broadcasting Corporation (Firm)
• 11 Bloomberg LP
• 10 CINEFETE (Firm)
• 10 Camille S. DeBose (Firm)
• 10 MacNeil/Lehrer Productions (Firm)
• 10 National Geographic Digital Media (Firm)
• 8 Cambridge Educational (Firm)
• 8 Mirror/Mirror Productions, Inc. (Firm)
• 8 NewsHour Productions LLC (Firm)
• 8 TVF International (Firm)
• 8 Video Education America (VEA) (Firm)
• 7 ClickView/VEA (Firm)

• 13 Earth (Planet)
• 8 Asia
• 8 United States
• 4 Africa, Sub-Saharan
• 4 North America
• 4 U.S. states
• 3 Africa
• 2 South Asia
• 1 Antarctica
• 1 Australia
• 1 Central America
• 1 China
• 1 Physical geography
• 1 South America
• 1 Southeast Asia

• 637 Internet videos
• 504 Video recordings for the hearing impaired
• 74 Educational films
• 68 Videorecording
• 6 Video recording

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