What Are Biomes?

Biomes (Terrestial) An Interdependent system of plants, animals and land Large regions with similar Ecosystems Tundra Taiga Desert Savanna Grassland Temperate forest Temperate rain forest Tropical rain forest

Biomes of the World Biomes: Characterized by their dominant vegetation & also by animals adapted to that environment Distribution of biomes is determined mostly by temperature & rainfall

Figure 50.24 The distribution of major terrestrial biomes

Biomes & Climate

Tropical Rainforests Occur near the equator Warm temperatures Days 11 – 12 hours long Rainfall is variable Very biodiverse (up to 300 species of trees) Poor soil

Tropical Rainforest

Savannas Grasslands with scattered trees Can be temperate or tropical Grasses main vegetation Animals include: giraffes, zebra, antelope, baboons, lions, cheetahs

Figure 50.25b Savanna

Deserts Hot during the day, cold at night Under 30 cm of rain per year Large deserts found near 30o N and 30o S latitude

Deserts Desertification: conversion of other biomes (especially savannas) to deserts Is a major ecological problem Plants include yucca & cactus Animals include snakes, birds, insects, lizards, rodents

Chaparral Region of dense spiny shrubs Mild, rainy winters & long, hot, dry summers Vegetation is adapted to periodic fires Animals include deer, fruit eating birds, seed eating rodents, lizards, & snakes

Figure 50.25d Chaparral

Temperate Grasslands Are mostly treeless except along rivers & streams Keys to persistence of grasslands: seasonal drought, fires & grazing by large mammals Amount of annual rainfall determines the height of the grassland vegetation

Temperate Deciduous Forests Grow in latitudes between 35o and 50o Areas must have sufficient moisture to grow trees Deciduous: leaf bearing trees (ex: oak, maple, cherry, hickory) Cold winters, hot summers

Temperate Deciduous Forests High precipitation year round Trees have a distinct annual rhythm Rich soil Animals include deer, bear, squirrels, raccoons, birds, insects

Taiga: Coniferous Forests Conifers: cone bearing trees (ex: pine, spruce, fir) Taiga: northern coniferous forests Taiga is cold, but many coniferous forests are temperate

Figure 20.25g Coniferous forests

Tundra Near the North Pole Little vegetation, but mostly mosses, lichens, & small shrubs Very cold Permafrost: layer of soil that remains permanently frozen

Tundra Very little precipitation, but swampy in the summer Animals include: artic fox and hare, insects (in summer), musk oxen, caribou

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