• 40 Environmental degradation
• 40 Human ecology
• 40 Life sciences
• 32 Environmental sciences
• 29 Effect of environment on
• 29 Human beings
• 12 Conservation of natural resources
• 12 Environmental law
• 12 Environmental policy
• 12 Environmental protection
• 11 Ecological regions
• 11 Human beings--Effect of environment on
• 9 Population
• 5 Pollution
• 5 Zoology
• 4 Air
• 4 Climatic changes
• 4 Global warming
• 3 Animal behavior
• 3 Behavior
• 3 Biodiversity
• 3 Environmental geography
• 3 Human geography

• 40 Films Media Group
• 21 Green Planet Films (Firm)
• 6 PBS (Firm)
• 3 Cerebellum Corporation (Firm)
• 3 Kwanza (Firm)
• 2 Australian Broadcasting Corporation (Firm)
• 1 ABC NEWS (Firm)
• 1 Allied Environmental Services Australia Pty Ltd (Firm)
• 1 BBC Worldwide Learning (Firm)
• 1 CNN (Firm)
• 1 Java Films (Firm)

• 38 English
• 1 Spanish
• 1 Unknown

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