Land BiomesLand Biomes

APES – LCHSAPES – LCHS

Dr.EDr.E

Introduction Introduction Biomes are the major regional groupings Biomes are the major regional groupings of plants and animals discernible at a of plants and animals discernible at a global scaleglobal scale

distribution patterns are correlated with distribution patterns are correlated with regional climate patterns and identified regional climate patterns and identified according to the climax vegetation typeaccording to the climax vegetation typea biome is composed not only of the climax a biome is composed not only of the climax vegetation, but also of immature vegetation, but also of immature communitiescommunities

To understand the nature of biomes To understand the nature of biomes one needs to learnone needs to learn

Global distribution patternGlobal distribution pattern1.1. Where each biome is found and Where each biome is found and

how each varies geographicallyhow each varies geographically

2.2. A given biome may be composed of A given biome may be composed of different taxa on different different taxa on different continentscontinents

To understand the nature of biomes To understand the nature of biomes one needs to learnone needs to learn

The dominant, characteristic, and The dominant, characteristic, and unique growth formsunique growth forms

vertical stratificationvertical stratification

leaf shape, size, and habitleaf shape, size, and habit

special adaptations of the special adaptations of the vegetationvegetation

To understand the nature of biomes To understand the nature of biomes one needs to learnone needs to learn

The types of animals (especially The types of animals (especially vertebrates) characteristic of the vertebrates) characteristic of the biome biome

Their typical morphological, Their typical morphological, physiological, and/or behavioral physiological, and/or behavioral adaptations to the environmentadaptations to the environment

Major BiomesMajor Biomes

DesertsDeserts

ForestsForests

GrasslandsGrasslands

TundraTundra

AquaticAquatic

DesertsDesertsDeserts cover about one fifth of the Earth’s Deserts cover about one fifth of the Earth’s surface and occur where rainfall is less than surface and occur where rainfall is less than 50 cm/year50 cm/year

Most deserts occur at low latitudesMost deserts occur at low latitudes

Another kind of desert, cold deserts, occur in Another kind of desert, cold deserts, occur in the basin and mountain rangesthe basin and mountain ranges

Most deserts have a considerable amount of Most deserts have a considerable amount of specialized vegetation, as well as specialized specialized vegetation, as well as specialized vertebrate and invertebrate animalsvertebrate and invertebrate animals

DesertsDesertsSoils often have abundant nutrients Soils often have abundant nutrients because they need only water to become because they need only water to become very productive and have little or no organic very productive and have little or no organic mattermatter

Disturbances are common in the form of Disturbances are common in the form of occasional fires or cold weather, and occasional fires or cold weather, and sudden, infrequent, but intense rains that sudden, infrequent, but intense rains that cause floodingcause flooding

Types of DesertsTypes of Deserts

Hot and DryHot and Dry

SemiaridSemiarid

CoastalCoastal

ColdCold

Hot and Dry DesertHot and Dry DesertTemperatureDesert surfaces receive a little more than twice

the solar radiation received by humid regions and lose almost twice as much heat at night

Many mean annual temperatures range from 20-25° C

The extreme maximum ranges from 43.5-49° C. Minimum temperatures sometimes drop to -18° C

Hot and Dry DesertHot and Dry DesertPrecipitation Rainfall is usually very low and/or concentrated in short

bursts between long rainless periods Evaporation rates regularly exceed rainfall rates Sometimes rain starts falling and evaporates before

reaching the ground Rainfall is lowest on the Atacama Desert of Chile, where

it averages less than 1.5 cm Inland Sahara also receives less than 1.5 cm a year Rainfall in American deserts is higher—almost 28 cm a

year

Hot and Dry DesertHot and Dry DesertSoilsSoils are course-textured, shallow, rocky or

gravely with good drainage and have no subsurface water

They are coarse because there is less chemical weathering

The finer dust and sand particles are blown elsewhere, leaving heavier pieces behind

Hot and Dry DesertHot and Dry DesertPlants

Canopy in most deserts is very rarePlants are mainly ground-hugging shrubs and short woody trees

Leaves are “replete” (fully supported with nutrients) with water-conserving characteristicsThey tend to be small, thick and covered with a thick cuticle (outer layer)In the cacti, the leaves are much-reduced (to spines) and photosynthetic activity is restricted to the stemsSome plants open their stomata (microscopic openings in the epidermis of leaves that allow for gas exchange) only at night when evaporation rates are lowest

Hot and Dry DesertHot and Dry Desert

Yuccas Ocotillo Turpentine bush Prickly Pears False mesquite

Sotol Ephedras

Agaves Brittlebush

Hot and Dry Hot and Dry DesertDesertAnimalsAnimals

The animals include small nocturnal (active at The animals include small nocturnal (active at night) carnivoresnight) carnivoresThe dominant animals are burrowers and The dominant animals are burrowers and kangaroo ratskangaroo ratsThere are also insects, arachnids, reptiles and There are also insects, arachnids, reptiles and birdsbirdsThe animals stay inactive in protected hideaways The animals stay inactive in protected hideaways during the hot day and come out to forage at during the hot day and come out to forage at dusk, dawn or at night, when the desert is coolerdusk, dawn or at night, when the desert is cooler

SnakesSnakes

LizardsLizards

Tortoise Tortoise Bighorn Sheep Bighorn Sheep

CoyoteCoyote Ants Ants

TarantulaTarantulaTarantula Wasp Tarantula Wasp

Semiarid DesertSemiarid DesertTemperatureTemperature

The summers are moderately long and dry, The summers are moderately long and dry, and like hot deserts, the winters normally and like hot deserts, the winters normally bring low concentrations of rainfallbring low concentrations of rainfallSummer temperatures usually average Summer temperatures usually average between 21-27° Cbetween 21-27° CIt normally does not go above 38° C and It normally does not go above 38° C and evening temperatures are cool, at around evening temperatures are cool, at around 10° C. 10° C.

Semiarid DesertSemiarid DesertPrecipitationCool nights help both plants and animals by

reducing moisture loss from transpiration, sweating and breathing

Condensation of dew caused by night cooling may equal or exceed the rainfall received by some deserts

As in the hot desert, rainfall is often very low and/or concentrated

The average rainfall ranges from 2-4 cm annually.

Semiarid DesertSemiarid Desert

Soilsranges from sandy and fine-textured to loose

rock fragments, gravel or sandfairly low salt concentration, compared to

deserts which receive a lot of rain (acquiring higher salt concentrations as a result)

there is no subsurface water.

Semiarid DesertSemiarid DesertPlantsThe spiny nature of many plants in semiarid deserts

provides protection in a hazardous environmentThe large numbers of spines shade the surface

enough to significantly reduce transpirationThe same may be true of the hairs on the woolly

desert plantsMany plants have silvery or glossy leaves, allowing

them to reflect more radiant energyThese plants often have an unfavorable odor or

taste.

Semiarid DesertSemiarid DesertCreosote bush

Bur sage

White thorn

Cat claw

Mesquite

Brittle bushes

Lyciums

Jujube

Semiarid DesertSemiarid Desert

AnimalsAnimalsDuring the day, insects move around twigs to During the day, insects move around twigs to

stay on the shady side; jack rabbits follow the stay on the shady side; jack rabbits follow the moving shadow of a cactus or shrubmoving shadow of a cactus or shrub

Naturally, many animals find protection in Naturally, many animals find protection in underground burrows where they are underground burrows where they are insulated from both heat and aridityinsulated from both heat and aridity

Semiarid DesertSemiarid DesertKangaroo rats

Rabbits Skunks

Side-blotched Lizard Mountain Lion

Mule Deer Rattlesnake Burrowing owls Western Bluebird

Coastal DesertCoastal DesertTemperatureTemperature

The cool winters of coastal deserts are followed The cool winters of coastal deserts are followed by moderately long, warm summersby moderately long, warm summers

The average summer temperature ranges from The average summer temperature ranges from 13-24° C; winter temperatures are 5° C or below13-24° C; winter temperatures are 5° C or below

The maximum annual temperature is about 35° The maximum annual temperature is about 35° C and the minimum is about -4° CC and the minimum is about -4° C

In Chile, the temperature ranges from -2 to 5° C In Chile, the temperature ranges from -2 to 5° C in July and 21-25° C in Januaryin July and 21-25° C in January

Coastal DesertCoastal DesertPrecipitationPrecipitation

The average rainfall measures 8-13 cm in The average rainfall measures 8-13 cm in many areasmany areas

The maximum annual precipitation over a The maximum annual precipitation over a long period of years has been 37 cm with a long period of years has been 37 cm with a minimum of 5 cmminimum of 5 cm

Coastal DesertCoastal DesertSoilsSoils

fine-textured with a moderate salt contentfine-textured with a moderate salt content

fairly porous with good drainage.fairly porous with good drainage.

Coastal DesertCoastal DesertPlantsPlants

extensive root systems close to the surface where they extensive root systems close to the surface where they can take advantage of any rain showerscan take advantage of any rain showersthick and fleshy leaves or stems can take in large thick and fleshy leaves or stems can take in large quantities of water when it is available and store it for quantities of water when it is available and store it for future usefuture usesome surfaces are corrugated with longitudinal ridges some surfaces are corrugated with longitudinal ridges and groovesand grooves

stem swells so that the grooves are shallow and the ridges far stem swells so that the grooves are shallow and the ridges far apartapartthe stem shrinks as water is used so that the grooves are deep the stem shrinks as water is used so that the grooves are deep and ridges close together. and ridges close together.

Coastal DesertCoastal Desert Salt bushSalt bush

Buckwheat BushBuckwheat Bush

Black bushBlack bush

Rice grassRice grass

Little Leaf HorsebrushLittle Leaf Horsebrush

Black SageBlack Sage

ChrysothamnusChrysothamnus

Coastal DesertCoastal DesertAnimalsAnimals

Some animals have specialized adaptations for Some animals have specialized adaptations for dealing with the desert heat and lack of waterdealing with the desert heat and lack of water

toads seal themselves in burrows with gelatinous toads seal themselves in burrows with gelatinous secretions and remain inactive for eight or nine secretions and remain inactive for eight or nine months until a heavy rain occursmonths until a heavy rain occursamphibians that pass through larval stages have amphibians that pass through larval stages have accelerated life cycles, which improves their chances accelerated life cycles, which improves their chances of reaching maturity before the waters evaporateof reaching maturity before the waters evaporateinsects lay eggs that remain dormant until the insects lay eggs that remain dormant until the environmental conditions are suitable for hatchingenvironmental conditions are suitable for hatchingfairy shrimps also lay dormant eggs. fairy shrimps also lay dormant eggs.

Coastal DesertCoastal Desert Chilean WoodstarChilean Woodstar

CaeciliansCaecilians

VulturesVultures

MiceMice

Fox Fox

ScorpionsScorpions

Cold DesertCold DesertTemperatureTemperature

Cold winters with snowfall and high overall Cold winters with snowfall and high overall rainfall throughout the winter and occasionally rainfall throughout the winter and occasionally over the summerover the summer

Antarctic, Greenland and the Nearctic realmAntarctic, Greenland and the Nearctic realm

short, moist, and moderately warm summers short, moist, and moderately warm summers with fairly long, cold winterswith fairly long, cold wintersmean winter temperature is between -2 to 4° C mean winter temperature is between -2 to 4° C and the mean summer temperature is between and the mean summer temperature is between 21-26° C 21-26° C

Cold DesertCold DesertPrecipitationPrecipitation

winters receive quite a bit of snowwinters receive quite a bit of snow

mean annual precipitation ranges from 15-26 mean annual precipitation ranges from 15-26 cmcm

annual precipitation has reached a maximum of annual precipitation has reached a maximum of 46 cm and a minimum of 9 cm46 cm and a minimum of 9 cm

heaviest rainfall of the spring is usually in April heaviest rainfall of the spring is usually in April or Mayor May

rainfall can be heavy in autumn in some areasrainfall can be heavy in autumn in some areas

Cold DesertCold DesertSoilSoil

heavy, silty, and saltyheavy, silty, and salty

relatively porous and drainage is good so relatively porous and drainage is good so that most of the salt has been leached outthat most of the salt has been leached out

Cold DesertCold DesertPlantsPlants

widely scatteredwidely scatteredareas of shad-scale, about 10 percent of the areas of shad-scale, about 10 percent of the ground is coveredground is covered

some areas of sagebush it approaches 85 some areas of sagebush it approaches 85 percentpercent

heights vary between 15 cm and 122 cm heights vary between 15 cm and 122 cm

deciduous, most having spiny leavesdeciduous, most having spiny leaves

Cold DesertCold Desert

Lichens Lichens

BryophytesBryophytes

Antarctic AlgaeAntarctic Algae

Snow AlgaeSnow Algae

KelpKelp

Cold DesertCold DesertAnimalsAnimals

population density can range from 14-41 population density can range from 14-41 individuals per hectareindividuals per hectare

all except the jack rabbits are burrowersall except the jack rabbits are burrowersalso applies to carnivores also applies to carnivores

several lizards do some burrowing and several lizards do some burrowing and moving of soilmoving of soil

deer are found only in the winterdeer are found only in the winter

Cold DesertCold DesertJack RabbitsJack Rabbits Kangaroo RatsKangaroo Rats

Kangaroo MiceKangaroo Mice

Pocket MicePocket Mice Grasshopper MiceGrasshopper Mice

Antelope Ground Squirrels Antelope Ground Squirrels

BadgerBadger Kit foxKit fox

Coyote Mule deerCoyote Mule deer

http://curriculum.calstatela.edu/courses/builders/lessons/less/biomes/deciduous/decweb.html

ForestsForestsoccupy approximately one-third of Earth’s land areaoccupy approximately one-third of Earth’s land area

account for over two-thirds of the leaf area of land account for over two-thirds of the leaf area of land plantsplants

contain about 70% of carbon present in living contain about 70% of carbon present in living thingsthings

are major casualties of deforestation, pollution, and are major casualties of deforestation, pollution, and industrial usage industrial usage

forest biomes are classified according to forest biomes are classified according to numerous characteristics, with seasonality numerous characteristics, with seasonality being the most widely usedbeing the most widely used

Types of ForestsTypes of Forests

Tropical Tropical

Temperate Temperate

Boreal forests (taiga) Boreal forests (taiga)

Tropical ForestsTropical Forestsare characterized by the greatest diversity of are characterized by the greatest diversity of speciesspecies

occur near the equator, within the area bounded occur near the equator, within the area bounded by latitudes 23.5 degrees N and 23.5 degrees Sby latitudes 23.5 degrees N and 23.5 degrees S

distinct seasonalitydistinct seasonalitywinter is absentwinter is absent

only two seasons are present (rainy and dry)only two seasons are present (rainy and dry)

The length of daylight is 12 hours and varies The length of daylight is 12 hours and varies little. little.

Tropical ForestsTropical Forests

Tropical ForestsTropical Forests

Tropical ForestsTropical Forests

TemperatureTemperature

average 20-25° C and varies little average 20-25° C and varies little throughout the yearthroughout the year

the average temperatures of the three the average temperatures of the three warmest and three coldest months do not warmest and three coldest months do not differ by more than 5 degreesdiffer by more than 5 degrees

Tropical ForestsTropical Forests

PrecipitationPrecipitationevenly distributed throughout the yearevenly distributed throughout the year

annual rainfall exceeds 2 meters annual rainfall exceeds 2 meters

Tropical ForestsTropical Forests

SoilSoilnutrient-poor and acidicnutrient-poor and acidic

decomposition is rapiddecomposition is rapid

subject to heavy leachingsubject to heavy leaching

Tropical ForestsTropical ForestsPlantsPlants

Canopy Canopy multilayered multilayered ContinuousContinuousallows little light penetrationallows little light penetration

Flora is highly diverseFlora is highly diverseone square kilometer may contain as many as 100 one square kilometer may contain as many as 100 different tree speciesdifferent tree species

Trees are 25-35 m tallTrees are 25-35 m tall buttressed trunks and shallow rootsbuttressed trunks and shallow rootsmostly evergreen, with large dark green leaves. mostly evergreen, with large dark green leaves.

Tropical ForestsTropical Forests

Plant AdaptationsPlant Adaptationsability to tolerate constant shade ability to tolerate constant shade

adapt strategies to reach sunlightadapt strategies to reach sunlight

Fungus is a good example of a plant that Fungus is a good example of a plant that flourishes in warm, dark places created by flourishes in warm, dark places created by the forest canopy and understory the forest canopy and understory

Tropical ForestsTropical Forests LianasLianas Epiphytes Epiphytes (grow on another plant)(grow on another plant)

FernsFerns

Moss Moss

CurareCurareForest CanopyForest Canopy Palms Palms

Tropical ForestsTropical Forests White-faced MonkeyWhite-faced Monkey Tree frogTree frog ToucanToucan

Vine SnakeVine Snake GeckoGecko Vested AnteaterVested Anteater Transparent butterflyTransparent butterfly

JaguarJaguar Unicorn grasshopperUnicorn grasshopper Red-eyed tree frogRed-eyed tree frog Silver-throated TanagerSilver-throated Tanager

Tropical king snakeTropical king snake ScorpionScorpion

http://curriculum.calstatela.edu/courses/builders/lessons/less/biomes/deciduous/decweb.html

Temperate ForestTemperate ForestTemperatureTemperature

Well-defined seasons with a distinct winter Well-defined seasons with a distinct winter characterize this forest biomecharacterize this forest biome

Moderate climate and a growing season of Moderate climate and a growing season of 140-200 days during 4-6 frost-free months 140-200 days during 4-6 frost-free months distinguish temperate forestsdistinguish temperate forests

Temperature varies from -30° C to 30° C.Temperature varies from -30° C to 30° C.

Temperate ForestTemperate Forest

Temperate ForestTemperate Forest

Temperate ForestTemperate ForestPrecipitationPrecipitation

(75-150 cm) is distributed evenly throughout (75-150 cm) is distributed evenly throughout the yearthe year

SoilsSoilsfertile, enriched with decaying litterfertile, enriched with decaying litter

Temperate ForestTemperate ForestPlantsPlants

Canopy Canopy moderately dense moderately dense allows light to penetrateallows light to penetrateresulting in well-developed and richly diversified resulting in well-developed and richly diversified understory vegetation and stratification of animalsunderstory vegetation and stratification of animals

Flora is characterized by 3-4 tree species per Flora is characterized by 3-4 tree species per square kilometersquare kilometerTrees are distinguished by broad leaves that are Trees are distinguished by broad leaves that are lost annuallylost annually

Temperate ForestTemperate ForestOakOak HickoryHickory BeechBeechHemlockHemlock MapleMaple BasswoodBasswoodCottonwoodCottonwood ElmElm Willow Spring-flowering herbsWillow Spring-flowering herbs

Bank VoleBank Vole

Black BearBlack Bear

Gray SquirrelGray Squirrel

RaccoonRaccoon

White-tailed Deer White-tailed Deer

Wild BoarWild Boar

CardinalCardinal

GoshawkGoshawk

TurkeyTurkey

Yellow-bellied Sapsucker Yellow-bellied Sapsucker

Rat Snake Rat Snake

Spring PeeperSpring Peeper

Temperate Temperate ForestForest

Temperate ForestTemperate ForestFurther subdivisions of this group are determined by Further subdivisions of this group are determined by seasonal distribution of rainfall: seasonal distribution of rainfall:

moist conifer and evergreen broad-leaved forestsmoist conifer and evergreen broad-leaved forests: wet winters and : wet winters and dry summers (rainfall is concentrated in the winter months and dry summers (rainfall is concentrated in the winter months and winters are relatively mild)winters are relatively mild)dry conifer forestsdry conifer forests: dominate higher elevation zones; low : dominate higher elevation zones; low precipitation.precipitation.Mediterranean forestsMediterranean forests: precipitation is concentrated in winter, less : precipitation is concentrated in winter, less than 1000 mm per yearthan 1000 mm per yeartemperate coniferoustemperate coniferous: mild winters, high annual precipitation : mild winters, high annual precipitation (greater than 2000 mm)(greater than 2000 mm)temperate broad-leaved rainforeststemperate broad-leaved rainforests: mild, frost-free winters, high : mild, frost-free winters, high precipitation (more than 1500 mm) evenly distributed throughout precipitation (more than 1500 mm) evenly distributed throughout the yearthe year

Only scattered remnants of original temperate forests remainOnly scattered remnants of original temperate forests remain

Boreal forests, or taigaBoreal forests, or taigarepresent the largest terrestrial biomerepresent the largest terrestrial biomeOccurs between 50 and 60 degrees Occurs between 50 and 60 degrees north latitudesnorth latitudesseasons are divided into short, moist, seasons are divided into short, moist, and moderately warm summers and and moderately warm summers and long, cold, and dry winterslong, cold, and dry winterslength of the growing season in boreal length of the growing season in boreal forests is 130 days forests is 130 days

                               

Boreal forests, or taigaBoreal forests, or taiga

Boreal forests, or taigaBoreal forests, or taigaTemperatures are very lowTemperatures are very low

Precipitation is primarily in the form of Precipitation is primarily in the form of snow, 40-100 cm annuallysnow, 40-100 cm annually

Soil is thin, nutrient-poor, and acidicSoil is thin, nutrient-poor, and acidic

Canopy permits low light penetration, Canopy permits low light penetration, and as a result, understory is limitedand as a result, understory is limited

Boreal forests, or taigaBoreal forests, or taigaThe conical or spire-shaped needleleaf trees common to the taiga The conical or spire-shaped needleleaf trees common to the taiga are adapted to the cold and the physiological drought of winter and are adapted to the cold and the physiological drought of winter and to the short-growing season: to the short-growing season:

Conical shape - promotes shedding of snow and prevents loss of branches. Conical shape - promotes shedding of snow and prevents loss of branches.

Needleleaf - narrowness reduces surface area (transpired), especially during Needleleaf - narrowness reduces surface area (transpired), especially during winter when the frozen ground prevents plants from replenishing their water winter when the frozen ground prevents plants from replenishing their water supply. The needles of boreal conifers also have thick waxy coatings--a supply. The needles of boreal conifers also have thick waxy coatings--a waterproof cuticle--in which stomata are sunken and protected from drying waterproof cuticle--in which stomata are sunken and protected from drying winds. winds.

Evergreen habit - retention of foliage allows plants to photosynthesize as Evergreen habit - retention of foliage allows plants to photosynthesize as soon as temperatures permit in spring, rather than having to waste time in the soon as temperatures permit in spring, rather than having to waste time in the short growing season merely growing leaves. short growing season merely growing leaves.

Dark color - the dark green of spruce and fir needles helps the foliage absorb Dark color - the dark green of spruce and fir needles helps the foliage absorb maximum heat from the sun and begin photosynthesis as early as possiblemaximum heat from the sun and begin photosynthesis as early as possible

Taiga Taiga PlantsPlantsBalsam FirBalsam Fir

Black Spruce Douglas-fir Black Spruce Douglas-fir

Paper Birch Eastern Red Cedar Jack PinePaper Birch Eastern Red Cedar Jack Pine

Siberian White Fir White Poplar Siberian White Fir White Poplar

SpruceSpruce

White Spruce White Spruce

Taiga AnimalsTaiga Animals

American Black Bear Bald Eagle American Black Bear Bald Eagle Bobcat Bobcat

Canadian Lynx Gray Wolf Grizzly Bear Canadian Lynx Gray Wolf Grizzly Bear

Long-Eared Owl Red Fox River Otter Long-Eared Owl Red Fox River Otter

Snowshoe Rabbit Wolverine Snowshoe Rabbit Wolverine

Boreal Boreal forests, forests, or taigaor taiga

GrasslandsGrasslandscharacterized as lands dominated by characterized as lands dominated by grasses rather than large shrubs or treesgrasses rather than large shrubs or trees

largest land animals due to huge largest land animals due to huge vegetationvegetation

There are two main divisions of There are two main divisions of grasslandsgrasslands

tropical grasslands called savannastropical grasslands called savannas

temperate grasslands. temperate grasslands.

SavannaSavannaSavanna is grassland with scattered individual Savanna is grassland with scattered individual treestreesClimate is the most important factor in creating a Climate is the most important factor in creating a savannasavannafires maintain an area as a savanna fires maintain an area as a savanna Types of Savannas Types of Savannas

climatic conditions are called climatic conditions are called climatic savannasclimatic savannassoil conditions not entirely maintained by fire are soil conditions not entirely maintained by fire are called called edaphic savannasedaphic savannasderived savannaderived savanna is the result of people clearing forest is the result of people clearing forest land for cultivation land for cultivation

SavannaSavanna

SavannaSavannaPrecipitationPrecipitation

always found in warm or hot climates where the always found in warm or hot climates where the annual rainfall is from about 50.8 to 127 cm (20-50 annual rainfall is from about 50.8 to 127 cm (20-50 inches) per yearinches) per year

crucial that the rainfall is concentrated in six or crucial that the rainfall is concentrated in six or eight months of the year, followed by a long eight months of the year, followed by a long period of drought when fires can occurperiod of drought when fires can occur

if the rain were well distributed throughout the if the rain were well distributed throughout the year, many such areas would become tropical year, many such areas would become tropical forestforest

SavannaSavannaSoilsSoils

porous, with rapid drainage of waterporous, with rapid drainage of water

only a thin layer of humus (the organic only a thin layer of humus (the organic portion of the soil created by partial portion of the soil created by partial decomposition of plant or animal matter), decomposition of plant or animal matter), which provides vegetation with nutrientswhich provides vegetation with nutrients

SavannaSavannaPlantsPlants

characterized by a continuous cover of characterized by a continuous cover of perennial grasses, often 3 to 6 feet tall at perennial grasses, often 3 to 6 feet tall at maturitymaturity

may or may not also have an open canopy may or may not also have an open canopy of drought-resistant, fire-resistant, or of drought-resistant, fire-resistant, or browse-resistant trees, or they may have an browse-resistant trees, or they may have an open shrub layeropen shrub layer

SavannaSavannaAnimalsAnimals

When the rains come, savanna bunch grasses When the rains come, savanna bunch grasses grow vigorouslygrow vigorously

larger grasses may grow an inch or more in 24 larger grasses may grow an inch or more in 24 hourshours

a surge of new life at this timea surge of new life at this time

for example, many antelope calves are bornfor example, many antelope calves are bornwith so much grass to feed on, mothers have plenty with so much grass to feed on, mothers have plenty of milkof milk

calves die if the rains fail to come. calves die if the rains fail to come.

SavannaSavannaAnimalsAnimals

do not all occur in the same savannado not all occur in the same savannagiraffes, zebras, buffaloes, kangaroos, mice, giraffes, zebras, buffaloes, kangaroos, mice, moles, gophers, ground squirrels, snakes, moles, gophers, ground squirrels, snakes, worms, termites, beetles, lions, leopards, worms, termites, beetles, lions, leopards, hyenas, and elephantshyenas, and elephants

GiraffesGiraffes ZebrasZebras Water buffaloesWater buffaloes

CheetahCheetah Baboon Baboon AntsAnts

CrocodileCrocodile Wild DogWild Dog Termites Termites

MeerkatsMeerkats LionsLions LeopardsLeopards

HyenasHyenas ElephantsElephants RhinocerosRhinoceros

Temperate GrasslandTemperate Grasslandgrasses as the dominant vegetation grasses as the dominant vegetation with trees and large shrubs absentwith trees and large shrubs absent

seasonal drought and occasional seasonal drought and occasional fires are very important to fires are very important to biodiversity. biodiversity.

effects aren’t as dramatic in temperate effects aren’t as dramatic in temperate grasslands as they are in savannas grasslands as they are in savannas

Temperate GrasslandTemperate GrasslandPrecipitationPrecipitation

usually occurs in the late spring and early usually occurs in the late spring and early summersummer

annual average is about 50.8 to 88.9 cm annual average is about 50.8 to 88.9 cm (20-35 inches). (20-35 inches).

Temperate GrasslandTemperate Grassland

Temperate GrasslandTemperate Grassland

Temperate GrasslandTemperate GrasslandTemperatureTemperature

range is very large over the course of the range is very large over the course of the yearyear

summer temperatures can be well over 38° C summer temperatures can be well over 38° C (100 degrees Fahrenheit(100 degrees Fahrenheit

winter temperatures can be as low as -40° C winter temperatures can be as low as -40° C (-40 degrees Fahrenheit)(-40 degrees Fahrenheit)

Temperate GrasslandTemperate GrasslandSoilSoil

deep and dark, with fertile upper layersdeep and dark, with fertile upper layers

nutrient-rich from the growth and decay nutrient-rich from the growth and decay of deep, many-branched grass rootsof deep, many-branched grass roots

rotted roots hold the soil together and rotted roots hold the soil together and provide a food source for living plants provide a food source for living plants

Temperate GrasslandTemperate GrasslandPlantsPlants

different species of grass grows best in a different species of grass grows best in a particular grassland environment particular grassland environment seasonal drought, occasional fires, and seasonal drought, occasional fires, and grazing by large mammals all prevent woody grazing by large mammals all prevent woody shrubs and trees from invading and becoming shrubs and trees from invading and becoming establishedestablisheda few trees, such as cottonwoods, oaks, and a few trees, such as cottonwoods, oaks, and willows grow in river valleys, and some willows grow in river valleys, and some nonwoody plants, specifically a few hundred nonwoody plants, specifically a few hundred species of flowers, grow among the grassesspecies of flowers, grow among the grasses

Temperate GrasslandTemperate GrasslandPurple needlegrass Blue GramaPurple needlegrass Blue Grama

Buffalo grass GalletaBuffalo grass Galleta

Asters Blazing StarsAsters Blazing Stars

Coneflowers GoldenrodsConeflowers Goldenrods

Sunflowers CloversSunflowers Clovers

Psoraleas Wild Indigos Psoraleas Wild Indigos

Temperate GrasslandTemperate GrasslandAnimalsAnimals

gazelles, zebras, rhinoceroses, wild gazelles, zebras, rhinoceroses, wild horses, lions, wolves, prairie dogs, jack horses, lions, wolves, prairie dogs, jack rabbits, deer, mice, coyotes, foxes, rabbits, deer, mice, coyotes, foxes, skunks, badgers, blackbirds, grouses, skunks, badgers, blackbirds, grouses, meadowlarks, quails, sparrows, hawks, meadowlarks, quails, sparrows, hawks, owls, snakes, grasshoppers, leafhoppers, owls, snakes, grasshoppers, leafhoppers, and spidersand spiders

TundraTundra: The Not-So Barren Land : The Not-So Barren Land

coldest of all the biomescoldest of all the biomescomes from the Finnish word comes from the Finnish word tunturiatunturia, , meaning treeless plainmeaning treeless plainfrost-molded landscapesfrost-molded landscapesextremely low temperaturesextremely low temperatureslittle precipitationlittle precipitationpoor nutrientspoor nutrients short growing seasonsshort growing seasons

TundraTundra: The Not-So Barren Land : The Not-So Barren Land

TundraTundra: The Not-So Barren Land : The Not-So Barren Land

TundraTundra: The Not-So Barren Land : The Not-So Barren Land

TemperatureTemperaturegrowing season ranges from 50 to 60 daysgrowing season ranges from 50 to 60 days

average winter temperature is -34° C (-30° F)average winter temperature is -34° C (-30° F)

average summer temperature is 3-12° C (37-average summer temperature is 3-12° C (37-54° F) which enables this biome to sustain 54° F) which enables this biome to sustain lifelife

TundraTundra: The Not-So Barren Land : The Not-So Barren Land

PrecipitationPrecipitation

may vary in different regions of the may vary in different regions of the arcticarctic

yearly precipitation, including melting yearly precipitation, including melting snow, is 15 to 25 cm (6 to 10 inches) snow, is 15 to 25 cm (6 to 10 inches)

TundraTundra: The Not-So Barren Land : The Not-So Barren Land

SoilSoilformed slowlyformed slowly

layer of permanently frozen subsoil called permafrost layer of permanently frozen subsoil called permafrost exists, consisting mostly of gravel and finer materialexists, consisting mostly of gravel and finer material

when water saturates the upper surface, bogs and ponds when water saturates the upper surface, bogs and ponds may form, providing moisture for plantsmay form, providing moisture for plants

no deep root systems in the vegetation of the arctic no deep root systems in the vegetation of the arctic tundra, however, there are still a wide variety of plants tundra, however, there are still a wide variety of plants that are able to resist the cold climate that are able to resist the cold climate

TundraTundra: The Not-So Barren Land : The Not-So Barren Land There are about 1,700 kinds of plants in the arctic There are about 1,700 kinds of plants in the arctic and subarcticand subarcticadapted to sweeping winds and disturbances of the adapted to sweeping winds and disturbances of the soilsoilshort and group together to resist the cold short and group together to resist the cold temperatures and are protected by the snow during temperatures and are protected by the snow during the winterthe wintercarry out photosynthesis at low temperatures and carry out photosynthesis at low temperatures and low light intensitieslow light intensitiesgrowing seasons are short and most plants growing seasons are short and most plants reproduce by budding and division rather than reproduce by budding and division rather than sexually by floweringsexually by flowering

TundraTundra: The Not-So Barren Land : The Not-So Barren Land

low shrubs, sedges, reindeer mosses, low shrubs, sedges, reindeer mosses, liverworts, and grasses liverworts, and grasses

400 varieties of flowers 400 varieties of flowers

crustose and foliose lichen crustose and foliose lichen

TundraTundra: The Not-So Barren Land : The Not-So Barren Land

AnimalsAnimals

Strategies evolved to withstand the Strategies evolved to withstand the harsh conditions of the tundra can be harsh conditions of the tundra can be divided among those species that are divided among those species that are resident and those that are migratoryresident and those that are migratory

TundraTundra: The Not-So Barren Land : The Not-So Barren Land ResidentResident

small number of bird (e.g., ptarmigan) and mammal (e.g., muskox, small number of bird (e.g., ptarmigan) and mammal (e.g., muskox, arctic hare, arctic fox, musk ox) arctic hare, arctic fox, musk ox) Morphological adaptations Morphological adaptations

large, compact bodieslarge, compact bodiesa thick insulating cover of feathers or fur a thick insulating cover of feathers or fur pelage and plumage that turns white in winter, brown in summerpelage and plumage that turns white in winter, brown in summer

Physiological adaptations Physiological adaptations ability to accumulate thick deposits of fat during the short growing seasonability to accumulate thick deposits of fat during the short growing seasoninsulation and as a store of energy for use during the winter, when animal insulation and as a store of energy for use during the winter, when animal species remain activespecies remain active

Population adaptations Population adaptations cyclical fluctuations in population size, best seen perhaps in the lemming, a cyclical fluctuations in population size, best seen perhaps in the lemming, a small rodent which is the major herbivore in the tundra's simple food chainsmall rodent which is the major herbivore in the tundra's simple food chainpredator populations and plant populations respond in kind to the peaks predator populations and plant populations respond in kind to the peaks and crashes of the herbivore populationsand crashes of the herbivore populations

TundraTundra: The Not-So Barren Land : The Not-So Barren Land

MigratoryMigratoryspecies such as waterfowl, shorebirds and species such as waterfowl, shorebirds and caribou adapt to the tundra by avoiding the caribou adapt to the tundra by avoiding the most severe conditions of wintermost severe conditions of wintereach year at the end of the short growing each year at the end of the short growing season they move southward into the boreal season they move southward into the boreal forest or beyond, but return to the tundra to forest or beyond, but return to the tundra to breed due to the long growing seasonbreed due to the long growing season

BibliographyBibliography1.1. http://www.ucmp.berkeley.edu/glossary/gloss5/biome/ihttp://www.ucmp.berkeley.edu/glossary/gloss5/biome/i

ndex.htmlndex.html

2.2. http://www.http://www.enchantedlearningenchantedlearning.com/biomes/marsh/freshwater..com/biomes/marsh/freshwater.shtmlshtml  

3.3. http://http://mbgnetmbgnet..mobotmobot.org/.org/  

4.4. http://www.http://www.runetrunet..eduedu/~/~swoodwarswoodwar/CLASSES/GEOG235/biomes/intro.html/CLASSES/GEOG235/biomes/intro.html

5.5. http://archive.globe.http://archive.globe.govgov//sdasda-bin/wt/-bin/wt/ghpghp//tgtg+L(en)+P(seasons/+L(en)+P(seasons/MiniinvestigationMiniinvestigation))

6.6. http://www.panda.org/about_wwf/where_we_work/http://www.panda.org/about_wwf/where_we_work/ecoregions/global200/pages/home.htmecoregions/global200/pages/home.htm