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What makes a biome a biome? Why is a rainforest different from desert? How does it affect life there?. Terrestrial Biomes.
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What makes a biome a biome? Why is a rainforest different from desert? How does it affect life there? Terrestrial Biomes Objective: Describe at least 4 plant adaptations for living in diverse terrestrial biomes, indicate how each adaptation useful, and why is the adaptation necessary for that biome.
What is a biome? • Biomes- large climatic regions that contain a number of smaller related ecosystems • Defined by • Climate—temperature and rainfall • Inhabitants with similar adaptations—vegetation • Rarely have distinct boundaries • Gradual change between biomes (desert to grassland, etc)
What biomes are there? • Tundra • Tropical forest • Temperate forest • Taiga • Temperate grassland • Savanna • Chaparral • Desert
Tundra • What? • Cold and treeless • Mosses, lichens, grasses, small woody • Caribou, musk oxen, snowy owls, arctic foxes, lemmings, snowshoe hares • Where? • North America • 1/5 of world’s land surface • Why? • Permafrost- permanently frozen layer of soil under the surface • Long cold winters two month growing season • Low precipitation (less than 12 cm/year) • Slow decay few nutrients • Soil thaws in summer, ponds form, and insects and birds arrive
Caribou Yellow Tundra Flower Polar Bear Ptarmigan Musk-ox
Human Impact on the Tundra • disruption of the vegetation leaves deep scars that may never heal (paths, vehicle tracks, etc.) • disruption of migratory patterns of birds and caribou by Alaskan oil pipeline, roads, fences • global climate change is causing permafrost to melt and change landscape
Forests 26 types of forests, divided into 3 types Tropical forest Temperate forest Taiga
Tropical Forest Where? • Near the equator • Asia, Africa, South America, Central America What? • Most productive biome • Tall trees and plants that grow year-round • High species richness and tons of biodiversity! • 1 hectare = 300 species of TREES (vs. 12 in deciduous forest) • Diverse animal life • Monkeys, snakes, lizards, birds • Insects- over 1 million of tree-dwelling • Altogether probably contain ½ of all the world’s species Why? • Stable warm temperatures • Abundant rainfall How? • Trees dominate and grow tall forming a canopy (continuous layer of treetops that shade forest floor)
Cool adaptation! • Epiphytes are mosses, orchids, and bromeliads that live on the branches of trees • Not parasites- they still do photosynthesis
Tropical Rainforest: Human Impact -Removal of the vegetation causes a loss of fertility in the soil, and it becomes as hard as cement. -Erosion by rain carries a great deal of soil into the rivers, causing loss of habitat there as well.
Much of the vegetation is cleared for farming of products such as palm oil, in a process called “slash and burn”. Farmers cut down sections of the forest to use for fields, but the soil is not very fertile, and after a while, does not give good crops. The farmer moves on to another section of the forest and repeats the process.
Temperate Deciduous Forest What? • Deciduous trees—shed leaves each year • Birch, beech, maple, oak, hickory, sycamore, elm, ash, willow, cottonwood • Bears, wolves, white-tailed deer, foxes, raccoons, squirrels Why? • Seasons with varied precipitation throughout the year • Average Annual Precipitation: 81 cm (32 in). • Warmer winters and longer summers than taiga • Average temperature: 24 °C (75 ° F) Often cut for timber or destroyed for farms, towns and cities Cool adaptation! Deciduous trees have broad thin leaves, large surface area for maximum light absorption
The Woodpecker They eat insects, especially from under the bark of trees. They peck with their beaks at the tree, and dig holes to get at the insects. A woodpecker’s skull is designed to allow it to absorb the shock of the bird pecking at a tree, and keeps the brain from being damaged. It has special air pockets within the bone, which absorb the impact.
Man’s impact on the Temperate Forest -Lots of logging -Also subject to pressure from housing, and over development. -Erosion and runoff are a big problem, especially when vegetation is removed.
Taiga What? • Coniferous trees- bear seed cones, typically evergreen • Waxy needle-shaped leaves to reduce water loss • Also called boreal forest • Moose, bears, wolves, lynxes, hares • Some adapted to survive winter (ex. hibernation), some migrate for winter Where? • South of tundra, north of temperate regions • Northern Europe, Asia, North America Why? • Long, cold winters • Short summers • Nutrient-poor soil • Cool adaptation! • Coniferous trees have waxy needle-shaped leaves to reduce water loss. Winter (at least 6 months) – 54 to -1° C (-65 to 30° F). Summer: -7° C (20° F)- 21° C (70° F)
Human Impact on the Taiga -The biggest impact on the taiga comes from the cutting of trees for lumber, and especially paper.
Temperate Grassland • Cool adaptation! • The actively growing part of the plant is at or below the ground (not tip of stem)- allows plant to survive grazing and fires What? • Grasses • Grazing mammals, such as bison Where? • Interior of continents • Same latitude as temperate deciduous forests • North America, Asia, Europe, Australia, South America Why? • Rich, fertile soil • Low rainfall—not enough to support trees Often transformed into farmland or grazing land for domesticated animals
Human Impact on the Grassland: -removal of the grasses for agriculture has resulted in a loss of soil. -many animals and plants have been removed because they are not “useful” to humans -over hunting has almost made some species extinct.
Savanna • Cool adaptations! • Trees shed leaves during dry season to conserve water • Above ground parts of grass die during dry season What? • Tropical or temperate grassland with some deciduous trees and shrubs • Large herbivores—zebras, wildebeests, giraffes, gazelles • Large carnivores—lions, leopards, cheetahs Where? • Africa, South America, Australia Why? • More rainfall than deserts, less than forests
Chaparral What? • Dense, spiny shrubs • Scattered coniferous trees • Coyotes, jack rabbits, mule deer, alligator lizards, horned toads, praying mantis, honey bee and ladybugs Where? • Middle latitudes • Costal regions—Mediterranean Sea & southern California Why? • Mild, rainy winters 10-17 inches of rain all year • Hot dry summers 30° and 100° F • Periodic fires
Chaparral • Cool adaptations! • Many plants have small hard leaves that hold water.
Deserts Where? • North Africa, central Australia, southwest North America, eastern Asia What? • Sparse vegetation with various adaptations to decrease water loss • Creosote bush has waxy coating that reduces evaporation • Few stomata (tiny openings in leaves where water escapes) • Kit foxes, lizards, snakes are nocturnal • Other animals burrow in ground or hide in shade Why? • Variable temperatures- not all hot! • Hot in summer, cold in winter and night • Very little rainfall—less than 25 cm rain per year Cool adaptation! The saguaro cactus has an expandable body that can store water and leaves that evolved into spines to protect from herbivores It can hold about 2,200 lbs of water!