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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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.