Table of Contents

1. Chapter 21 Ecosystems Table of Contents Section 1 Terrestrial Biomes Section 2 Aquatic Ecosystems

2. Section 1 Terrestrial Biomes Chapter 21 Objectives • Identifythe eight major biomes. • Comparetundra with taiga. • Comparethe different kinds of forests. • Comparethe different kinds of grasslands. • Describethe adaptations of desert organisms.

3. Section 1 Terrestrial Biomes Chapter 21 The Major Biomes • The major types of terrestrial ecosystems, known as biomes, are tundra, tropical forest, temperate forest, taiga, temperate grassland, savanna, chaparral, and desert.

4. Section 1 Terrestrial Biomes Chapter 21 Earth’s Major Biomes

5. Section 1 Terrestrial Biomes Chapter 21 Tundra • Tundrais a cold biome characterized by permafrost under the surface of the ground.

6. Section 1 Terrestrial Biomes Chapter 21 Forests • Tropical Forests • Tropical forests receive abundant rainfall and have stable temperatures. • They have a greater species richness than any other biome.

7. Section 1 Terrestrial Biomes Chapter 21 Forests, continued • Temperate Forests • Temperate forests have coniferous trees, which bear seeds in cones, or deciduous trees, which shed their leaves each year.

8. Section 1 Terrestrial Biomes Chapter 21 Forests, continued • Temperate Deciduous Forests • The trees in temperate deciduous forests shed all of their leaves in the fall.

9. Section 1 Terrestrial Biomes Chapter 21 Forests, continued • Taiga • Taigais cold but is warmer than tundra and receives more precipitation. • Taiga is dominated by coniferous forests.

10. Section 1 Terrestrial Biomes Chapter 21 Grasslands • Temperate Grasslands • Temperate grasslandsoccur in areas with cold winters and hot summers. • They are dominated by grasses and herds of grazing animals.

11. Section 1 Terrestrial Biomes Chapter 21 Grasslands, continued • Savanna • Savannasare tropical grasslands with alternating wet and dry seasons. • They are dominated by herds of grazing animals.

12. Section 1 Terrestrial Biomes Chapter 21 Grasslands, continued • Chaparral • Chaparralis found in coastal regions with warm, dry summers and mild winters. • It is dominated by dense, spiny shrubs.

13. Section 1 Terrestrial Biomes Chapter 21 Deserts • Deserts receive less than 25 cm (9.9 in.) of precipitation per year. • Desert inhabitants have adaptations for conserving water.

14. Section 2 Aquatic Ecosystems Chapter 21 Objectives • Identifythe major ocean zones. • Comparethe aphotic zone with the photic zone. • Comparethe neritic zone with the oceanic zone. • Describeestuaries. • Compareeutrophic lakes with oligotrophic lakes. • Explainthe significance of gradient in rivers and streams. • Describefreshwater wetlands.

15. Section 2 Aquatic Ecosystems Chapter 21 Ocean Zones • The photic zone in the ocean receives light, but the aphotic zone does not. • Other zones of the ocean are defined based on their relative locations.

16. Section 2 Aquatic Ecosystems Chapter 21 Ocean Zones, continued • The Intertidal Zone • In the intertidal zone, organisms must be able to tolerate drying and pounding by waves.

17. Section 2 Aquatic Ecosystems Chapter 21 Intertidal Zone

18. Section 2 Aquatic Ecosystems Chapter 21 Ocean Zones, continued • The Neritic Zone • The neritic zonereceives nutrients from the bottom of the ocean and from land. It is the ocean’s richest zone in terms of the number of species and individuals.

19. Section 2 Aquatic Ecosystems Chapter 21 Neritic Zone

20. Section 2 Aquatic Ecosystems Chapter 21 Ocean Zones, continued • The Oceanic Zone • Production in the oceanic zone is limited by a shortage of nutrients.

21. Section 2 Aquatic Ecosystems Chapter 21 Ocean Zones, continued • Estuaries • Estuariesare very productive areas where rivers and streams flow into the sea.

22. Section 2 Aquatic Ecosystems Chapter 21 Freshwater Zones • Lakes and Ponds • Oligotrophic lakes are clear and lacking in nutrients. • Eutrophic lakes are rich in nutrients and are often murky.

23. Section 2 Aquatic Ecosystems Chapter 21 Three Lake Zones

24. Section 2 Aquatic Ecosystems Chapter 21 Freshwater Zones, continued • Rivers and Streams • Rivers and streams are bodies of water that flow down an elevation gradient within a watershed.

25. Section 2 Aquatic Ecosystems Chapter 21 Freshwater Zones, continued • Freshwater Wetlands • Freshwater wetlands are areas of land, such as marshes and swamps, that are covered with fresh water for at least part of each year.

26. Section 2 Aquatic Ecosystems Chapter 21 Freshwater Biomes