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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