• 17 Videos, Slides, Films

• 11 Natural resources
• 10 Hydrology
• 8 Environmental aspects
• 7 Land use
• 7 Population
• 6 Cultural geography
• 6 Ecosystem management
• 6 Rivers
• 6 Social ecology
• 6 Voyages and travels
• 5 Human geography
• 5 Marine biology
• 5 Pollution
• 4 Ecology
• 4 Refuse and refuse disposal
• 4 Toxicology
• 3 Biotic communities
• 3 Conservation of natural resources
• 3 Effect of human beings on
• 3 Human ecology
• 3 International economic relations
• 3 Marine ecology
• 3 Marine organisms

• 6 Looking Glass Pictures
• 4 Agency for Instructional Technology
• 1 Ampersand Film & Video Tape Productions
• 1 Electric Sky (Firm)
• 1 Journeyman Pictures (Firm)
• 1 Mundomedia Digital Studios, LLC
• 1 National Geographic Television & Film

• 17 English

• 1 Africa
• 1 Africa, Sub-Saharan
• 1 Asia
• 1 Bicol River (Philippines)
• 1 Cauvery River (India)
• 1 China
• 1 Costa Rica
• 1 Earth (Planet)
• 1 Europe
• 1 Greece
• 1 Mekong River
• 1 Mexico, Gulf of
• 1 North America
• 1 Red River Delta (Vietnam)
• 1 Tonle Sap (Cambodia : Lake)
• 1 Zuo River (China)

• 17 Educational films
• 17 Internet videos
• 17 Videorecording
• 4 Video recordings for the hearing impaired

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