1. A naturally raised area of land, not as high or craggy as a mountain.
5. Fog or haze intensified by smoke or other atmospheric pollutants.
7. A woody perennial plant, typically having a single stem or trunk growing to a considerable height and bearing lateral branches at some distance from the ground.
8. The surroundings or conditions in which a person, animal, or plant lives or operates.
11. A colourless unstable toxic gas with a pungent odour and powerful oxidizing properties, formed from oxygen by electrical discharges or ultraviolet light.
12. A substance used for destroying insects or other organisms harmful to cultivated plants or to animals.
14. A living organism typically growing in a permanent site, absorbing water and inorganic substances through its roots, and synthesizing nutrients in its leaves by photosynthesis using the green pigment chlorophyll.
16. A large natural stream of water flowing in a channel to the sea, a lake or other body of water.
2. The weather conditions prevailing in an area in general or over a long period.
3. A large area of water surrounded by land.
4. A gradual increase in the overall temperature of the earth's atmosphere generally attributed to the greenhouse effect caused by increased levels of carbon dioxide, CFCs, and other pollutants.
6. The symbolic color of environmentalism and sustainability. In many cultures, this color associated with nature and growth.
9. A community of plants, animals and smaller organisms that live, feed, reproduce and interact in the same area or environment.
10. A process of converting waste materials into reusable material.
13. The planet on which we live.
15. The invisible gaseous substance surrounding the earth, a mixture mainly of oxygen and nitrogen
17. The condensed moisture of the atmosphere falling visibly in separate drops.