Environment

2. a large amount of water covering an area that is usually dry
5. a situation in which there is not enough food for a great number of people
8. wild animals collectively
11. the action or process of converting waste into reusable material
13. the natural home or environment of an animal, plant, or other organism
15. If you reduce something, you make it smaller in size or amount, or less in degree
17. the process by which land changes into desert
18. is all the animals, plants, and other things in the world that are not made by people, and all the events and processes that are not caused by people
20. a mixture of smoke, gases, and chemicals

1. this is the study of the relationships between plants, animals, people, and their environment
3. a long period of time during which no rain falls
4. (of a species) seriously at risk of extinction.
6. to become liquefied by warmth or heat
7. the introduction of harmful materials into the environment
9. the clearing or thinning of forests by humans
10. is a process that occurs when gases in Earth's atmosphere trap the Sun's heat
12. the composite or generally prevailing weather conditions of a region
14. material or things that are no longer wanted or needed
16. keep safe or rescue (someone or something) from harm or danger
19. all the living things in an area and the way they affect each other and the environment