Life Support Systems

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Across 5. A major regional group of plant/animal communities best adapted to the region's environment. 6. The type of salination that is often the combination of over-irrigation and drylands. Cities are often located on drylands, leaving the rich soils for agriculture. Irrigation is also now common in cities (gardens and recreation areas). 7. Also called manioc, a staple in much of Africa. Tapioca starch is made from this. 13. The removal of soil nutrients and the loss of topsoil rich in organic matter, caused by erosion 17. Model that illustrates the flow of energy 18. The effect of mostly water vapour and carbon dioxide in the atmosphere 19. To "feed" with water 21. Occurs when cold air is below and warm air is above, trapping pollution around a city 22. A mixture of sulfur dioxide and nitrogen oxide pollutants reach the Earth in the form of rain or solid particles 24. The maximum production of fish, grain and livestock. 27. 9900 joules per day, the minimum energy intake per person 29. A pollutant found in refrigerators and aerosol cans 30. Removal of salt from seawater

Down 1. Largest river in China 2. More than enough water 3. Where the Oak Ridges Moraine is located (name the country) 4. The buildup of excess salts in soil, restricting amount of water and essential nutrient uptake by plants. 8. Gases that include carbon oxide and carbon dioxide 9. The different sections of the energy pyramid 10. Water-saturated sand 11. An irritating gas that forms just above the Earth's surface 12. The cause of increased amount of UV radiation reaching the Earth's surface 14. Type of air pollution resulting from the burning of fossil fuels 15. The movement of pollutants from the U.S. to Canada 16. Land that can be used for growing crops 18. The predicted rise in average temperature in the 21st century 20. Town in Ontario where 2300 people got sick from drinking infected water 23. Countries that suffer the most from lack of water 25. A type of irrigation system, 95% 26. Pollution caused by reactions between automobile exhaust and industrial emissions 28. Sea in Asia, where the worst water-related ecological disaster ever happened

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