• 570 Videos, Slides, Films

• 164 Ecological regions
• 151 Pollution
• 150 Biotic communities
• 123 Biodiversity
• 117 Conservation of natural resources
• 117 Environmental law
• 117 Environmental policy
• 117 Environmental protection
• 103 Ecology
• 102 Air
• 102 Climatic changes
• 102 Global warming
• 87 Life sciences
• 85 Biology
• 83 Natural resources
• 68 Ecological zones
• 55 Water use
• 52 Water
• 46 Toxicology
• 43 Land use
• 43 Water-supply
• 42 Endangered ecosystems
• 42 Endangered species
• 37 Human ecology

• 570 Films Media Group
• 93 PBS (Firm)
• 42 BBC (Firm)
• 40 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)
• 12 Australian Broadcasting Corporation (Firm)
• 12 Films for the Humanities & Sciences (Firm)
• 11 Bloomberg LP
• 10 CINEFETE (Firm)
• 10 Camille S. DeBose (Firm)
• 10 MacNeil/Lehrer Productions (Firm)
• 10 National Geographic Digital Media (Firm)
• 9 Filmhub (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)
• 7 National Geographic Society (U.S.)

• 562 English
• 5 Unknown
• 2 Spanish
• 1 Indonesian

• 9 Asia
• 4 Africa, Sub-Saharan
• 4 North America
• 4 U.S. states
• 2 Africa
• 2 South Asia
• 1 Antarctica
• 1 Australia
• 1 Central America
• 1 China
• 1 Physical geography
• 1 South America
• 1 Southeast Asia
• 1 United States

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