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biome

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biome

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  1. biome • Regions that have distinctive climates and organisms and that contain many separate but similar ecosystems

  2. Tropical rain forests • Warm, wet biome that occurs in a belt around the Earth near the equator and that contains the greatest diversity of organisms on Earth

  3. canopy • In a forest, the covering of tall tress whose intertwining branches absorb a great amount of sunlight and shade the area beneath

  4. Temperate rain forests • Cool, humid biome where tree branches are draped with mosses, tree trunks are covered with lichens, and the forest floor is covered with ferns

  5. Temperate deciduous forest • Forest in an area of extreme seasonal variation in which trees drop their leaves each fall

  6. taiga • Biome dominated by conifers and characterized by harsh winters; occurs just below the Arctic Circle; also called northern coniferous forest

  7. Chapter 4: Kinds of Ecosystems • Section 4.1: Forests • Biomes: • Each biome contains many individual ecosystems • Named for their plant life • Climate determines what plant life can grow in a certain area -temperature and precipitation

  8. Chapter 4: Kinds of Ecosystems • Tropical Rain Forests: • Air is hot and heavy with humidity • Get 100 in of rain a year • Strong sunlight year round, little seasonal variation in temperature • Climate is ideal for growing plants – more than another other biome • 1 acre of temperate forest contains about 10 species of trees, the same area of a tropical rain forest may contain over 100 species

  9. Chapter 4: Kinds of Ecosystems • Tropical Rain Forests: • Plant Adaptations: • Plants grow in layers • Trees more than 100 ft tall form a dense canopy which absorbs at least 95% of the sunlight • Below the canopy, only trees and shrubs adapted to shade can grow there – herbs with large leaves • Orchids and monkey ladder vines, use the tall tree trunks for support high in the canopy, where there is light for photosynthesis

  10. Chapter 4: Kinds of Ecosystems • Tropical Rain Forests: • Animal Adaptations: • Most rain-forest animals are specialists – organisms adapted to exploit a specific resource in a particular way to avoid competition • Ex: several species of birds called antwrens that eat insects, but each species catches insects in a different layer of forest vegetation • Escaping predators • Snaring prey • Camouflage – shaped like leaves or twigs, blend in perfectly with plants, poisons in their skin that are bright colored to warn predators

  11. Chapter 4: Kinds of Ecosystems • Tropical Rain Forests: • Threats to Rain Forests: • Used to cover 20% of the Earth’s surface, now about 7% • Logging strips rain forests the size of North and South Carolina combined each year • This leads to plants and animals becoming extinct • Malaysian nomads are often displaced, culture and tradition lost

  12. Chapter 4: Kinds of Ecosystems • Temperate Forests: • Temperate Rain forests: • Occur in North and South America, Australia and New Zealand • Pacific Northwest is the only area of temperate rain forest in America • 300 ft. tall evergreen trees, ferns; cool, humid climate, rarely freezes • Temperate Deciduous Forests: • Trees drop their leaves in the fall • Seasonal variations can be extreme (95° - below freezing) • Rainfall = 30 – 100”/ year – contributes to rich, deep soils

  13. Chapter 4: Kinds of Ecosystems • Temperate deciduous forests • Plant adaptations: • Plants grow in layers • Forest floor gets more sun than in the rain forest so ferns, herbs, and mosses grow • Adapted to survive seasonal changes • Winter: shed leaves (not enough moisture to support them), underground stems become dormant • Spring: grow leaves, seeds germinate

  14. Chapter 4: Kinds of Ecosystems • Temperate deciduous forests: • Animal Adaptations: • Exploit the forest plants for food and shelter • Squirrels eat nuts, seeds, and fruits in the tree tops • Bears eat the leaves and berries of plants • Birds nest in the safety of the canopy • Mammals and insects hibernate for the winter, birds fly south

  15. Chapter 4: Kinds of Ecosystems • Taiga: • Rough terrain • Forest floor is sparsely vegetated • Also known as the northern coniferous forest • Stretches across the northern hemisphere, just below the arctic circle • Long, extremely cold winters • 50 days of growing season • Most precipitation falls as snow

  16. Chapter 4: Kinds of Ecosystems • Taiga: • Plant adaptations: • Conifer: a tree whose seeds develop in cones • Leaves’ narrow shape and waxy coating retain water for the tree when the moisture in the ground is frozen • Pointed shape helps shed snow which would otherwise crush it • Dominate tree species: pine, hemlock, fir, and spruce • Conifer needles contain acidic substances that acidify the soil when the needles fall • Most plants can’t grow in acidic soil so forest floor is bare except for blueberries, ferns, and mosses

  17. Chapter 4: Kinds of Ecosystems • Taiga: • Animal Adaptations: • Lakes and swamps attract birds, fish, and other wetland organisms • Birds migrate south for the winter • Shrews and voles burrow underground during the winter • Moose and arctic hares (rabbits) eat what vegetation they can find • Hares have adapted to avoid predation by lynx, wolves, and foxes by shedding their brown summer fur and growing white fur to blend into the snow.