Ecosystem Processes and Ecosystem Processes and BiomesBiomes

OverviewOverviewDescribing Life on EarthDescribing Life on Earth

Taxonomic HierarchyTaxonomic HierarchyClassifying speciesClassifying speciesBiogeographicalBiogeographical RealmsRealms

TrophicTrophic HierarchyHierarchyEnergy and nutrient flowEnergy and nutrient flowFood chains and Food websFood chains and Food websNutrient CyclesNutrient Cycles

Ecological HierarchyEcological HierarchyCommunities and AssemblagesCommunities and AssemblagesStability, succession and disturbanceStability, succession and disturbanceTerrestrial EcosystemsTerrestrial EcosystemsBiomesBiomes

BiomesBiomesFormation classesFormation classes

Biogeography: the study of the Biogeography: the study of the distributions of plants and animals and distributions of plants and animals and related ecosystems; the geographical related ecosystems; the geographical relationships with their environments relationships with their environments over timeover time

The BiosphereThe BiosphereThe biosphere encompasses all of the living The biosphere encompasses all of the living species on earth (Biodiversity)species on earth (Biodiversity)

What the species areWhat the species areHow they interact with each otherHow they interact with each otherHow they are distributed over the globeHow they are distributed over the globe

Scientific perspectives derive fromScientific perspectives derive fromEvolutionary theoryEvolutionary theory

Genetic relationship between speciesGenetic relationship between speciesNatural selectionNatural selection

Interaction with each other through competition for resourcesInteraction with each other through competition for resourcesEcologyEcology

CoCo--occurrence of species in given areasoccurrence of species in given areasCompetition (especially in food chains) regulates the flow of Competition (especially in food chains) regulates the flow of energy through energy through

Global classification based onGlobal classification based onEvolutionary linkages (Realms and Regions)Evolutionary linkages (Realms and Regions)Ecological relationships (Biomes)Ecological relationships (Biomes)

Hierarchies of LifeHierarchies of LifeBiodiversity is shaped by the Biodiversity is shaped by the interactions ofinteractions of speciesspecies that result in the that result in the formation of formation of stable groupsstable groups (or unstable (or unstable groups) of species through the groups) of species through the regulation of the regulation of the flow of energy and flow of energy and nutrients.nutrients.

Taxonomic hierarchies Taxonomic hierarchies organization of related speciesorganization of related species

TrophicTrophic hierarchieshierarchiesorganization of energy and nutrient floworganization of energy and nutrient flow

Ecological hierarchiesEcological hierarchiesorganization of species into groupsorganization of species into groups

Taxonomic HierarchyTaxonomic HierarchyTaxonomy: the systematic classification of Taxonomy: the systematic classification of plants, animals and other life forms according plants, animals and other life forms according to presumed natural relationshipsto presumed natural relationshipsTaxonTaxon: a group or entity within a : a group or entity within a classification system (pl. classification system (pl. taxataxa))

SpeciesSpeciesGenusGenusFamilyFamilyOrderOrderClassClassPhylumPhylumKingdomKingdom

Groupings based on identified evolutionary Groupings based on identified evolutionary relationshipsrelationships

specific

general

Species are classified according to:Species are classified according to:Morphology Morphology –– similarity of physical and behavioral similarity of physical and behavioral traitstraitsReproductive criteriaReproductive criteriagenetic relationshipsgenetic relationships

Species named with Latin binomials, Species named with Latin binomials, according to taxonomic criteriaaccording to taxonomic criteria

Genus + Specific epithetGenus + Specific epithetExample: Genus Example: Genus SyzygiumSyzygium

SyzygiumSyzygium inophylloidesinophylloidesS. S. samarangensesamarangenseS. S. dealatumdealatumS. S. savaiiensesavaiiense

Groupings into similar genera and families implies Groupings into similar genera and families implies evolutionary linkageevolutionary linkage

KingdomsKingdomsKingdom Kingdom MoneraMonera (prokaryotic bacteria and (prokaryotic bacteria and cyanobacteriacyanobacteria))Kingdom Kingdom ProtistaProtista (eukaryotic single(eukaryotic single--cell cell organisms; protozoa, amoebas, organisms; protozoa, amoebas, multicellularmulticellular algae)algae)Kingdom Kingdom MyceteaeMyceteae: fungi: fungiKingdom Kingdom AnimaliaAnimalia: animals: animalsKingdom Kingdom PlantaePlantae: plants: plants

Links (Links (11))

Kingdom Kingdom PlantaePlantae: Phyla: PhylaBryophytaBryophyta: mosses: mossesPteridophytaPteridophyta: ferns: fernsConiferophytaConiferophyta: conifers (gymnosperms): conifers (gymnosperms)AnthophytaAnthophyta: flowering plants : flowering plants (angiosperms)(angiosperms)

monocotyledonsmonocotyledonsdicotyledonsdicotyledons

OthersOthers

Kingdom Kingdom AnimaliaAnimaliaInvertebratesInvertebrates

Arthropods (Insects, spiders, mites, crustaceans)Arthropods (Insects, spiders, mites, crustaceans)MollusksMollusksFlatwormsFlatwormsRoundwormsRoundwormsEarthwormsEarthwormsJellyfish, coralsJellyfish, coralsStarfish, spongesStarfish, sponges

VertebratesVertebratesFishFishAmphibiansAmphibiansReptilesReptilesBirdsBirdsMammalsMammals

There are roughly 1.8 million known species There are roughly 1.8 million known species on Earthon Earth

Estimates on total species vary between 4 million Estimates on total species vary between 4 million and 20 millionand 20 million

Taxonomic distributionTaxonomic distribution56% Insects56% Insects

Beetles (Beetles (ColeoptraColeoptra) comprise 24% of the total) comprise 24% of the total17% Other arthropods and invertebrates17% Other arthropods and invertebrates14% Plants14% Plants9% Algae, 9% Algae, protozoansprotozoans, fungi, fungi2.7% Vertebrates2.7% Vertebrates1% Bacteria and viruses1% Bacteria and viruses

Numbers of described species by major Numbers of described species by major taxataxaInsectaInsecta: 751,000: 751,000PlantaePlantae ((MulticellularMulticellular plants): 248,428plants): 248,428NonNon--insect insect arthropodaarthropoda (mites, spiders, crustaceans): 123,151(mites, spiders, crustaceans): 123,151MolluscaMollusca: 50,000: 50,000Fungi: 46,983Fungi: 46,983Protozoa: 30,800Protozoa: 30,800Algae: 26,900Algae: 26,900Pisces (fish): 19,056Pisces (fish): 19,056PlatyhelminthesPlatyhelminthes (flatworms): 12,200(flatworms): 12,200NematodaNematoda (roundworms): 12,000(roundworms): 12,000AnnelidaAnnelida (Earthworms): 12,000(Earthworms): 12,000Aves (Birds): 9,040Aves (Birds): 9,040CoelenterataCoelenterata (Jellyfish, corals): 9,000(Jellyfish, corals): 9,000ReptiliaReptilia: 6,300: 6,300EchinodermataEchinodermata (starfish, etc.): 6,100(starfish, etc.): 6,100PoriferaPorifera (sponges): 5,000(sponges): 5,000MoneraMonera (Bacteria, blue(Bacteria, blue--green algae): 4,760green algae): 4,760AmphibiaAmphibia: 4,184: 4,184MammaliaMammalia: 4,000: 4,000

BiogeographicBiogeographic RealmsRealms

RealmsRealmsAs continental masses separated off from As continental masses separated off from each other, their isolation from each other each other, their isolation from each other allowed their species to evolve separately, allowed their species to evolve separately, giving rise to unique assemblagesgiving rise to unique assemblagesOceans form main barrier to spread, but also Oceans form main barrier to spread, but also mountains, climatic conditionsmountains, climatic conditions

Trophic HierarchyTrophic HierarchyOrganizing life according to the flow of energyOrganizing life according to the flow of energy

Solar energySolar energyCritical role of plants: photosynthesisCritical role of plants: photosynthesistrophic levels, trophic levels, foodchainsfoodchains, efficiency, food , efficiency, food pyramidspyramids

Producers: plants (Producers: plants (autotrophsautotrophs))Consumers (Consumers (heterotrophsheterotrophs))

Primary consumers: herbivoresPrimary consumers: herbivoresSecondary consumers: carnivoresSecondary consumers: carnivoresTertiary consumers: higher order carnivores, omnivoresTertiary consumers: higher order carnivores, omnivores

Food Chains & Food websFood Chains & Food websChains indicate linear pathways of energy flow Chains indicate linear pathways of energy flow (single path)(single path)Food webs illustrate complex multiple pathwaysFood webs illustrate complex multiple pathwaysEfficiency: Loss of energy at each level Efficiency: Loss of energy at each level

AbioticAbiotic ComponentsComponentsLight: photoperiodLight: photoperiodClimate: temperature and waterClimate: temperature and waterAltitudinal zones (life zones)Altitudinal zones (life zones)

Increases in altitude mimic increases in latitudeIncreases in altitude mimic increases in latitudeNormal lapse rate: temperatures cool with Normal lapse rate: temperatures cool with increasing altitude: changing climatic patternsincreasing altitude: changing climatic patterns

Elemental cycles (biogeochemical cycles)Elemental cycles (biogeochemical cycles)Nitrogen cycleNitrogen cycleCarbon and oxygen cycleCarbon and oxygen cycle

Limiting factors: an Limiting factors: an abioticabiotic or chemical factor or chemical factor that is in short supply and inhibits ecosystems that is in short supply and inhibits ecosystems from operating at full potential. from operating at full potential.

TrophismTrophism

Producers, consumers, Producers, consumers, detrivoresdetrivores, decomposers, decomposersFood chains and food websFood chains and food websTrophic levelsTrophic levels

ProducersProducersplantsplants

Primary consumersPrimary consumersherbivoresherbivores

Secondary consumersSecondary consumerscarnivorescarnivores

Tertiary consumersTertiary consumershigher level carnivoreshigher level carnivores

Critical Role of PlantsCritical Role of PlantsA vital link between the A vital link between the abioticabiotic and biotic and biotic componentscomponents

with help from soil biotawith help from soil biota

PhotosynthesisPhotosynthesisStores Carbon dioxide, water, and energyStores Carbon dioxide, water, and energyCreates Carbohydrates and oxygenCreates Carbohydrates and oxygen

6CO6CO22 + 6H+ 6H22 OO CC66 HH1212 OO66 + 6O+ 6O22

RespirationRespirationReleases stored energy, carbon dioxide and water vaporReleases stored energy, carbon dioxide and water vapor

CC66 HH1212 OO66 + 6O+ 6O22 6CO6CO22 + 6H+ 6H22 OOPlants also intercept Nitrogen, a building block of Plants also intercept Nitrogen, a building block of proteinsproteinsNet Primary Productivity: photosynthesis usually Net Primary Productivity: photosynthesis usually exceeds respiration.exceeds respiration.

Net primary productivity results in increased biomass Net primary productivity results in increased biomass Biomass: net dry weight of organic materialBiomass: net dry weight of organic material

Consider also grassConsider also grass--fed beef; although similar inefficiencies exist, fed beef; although similar inefficiencies exist, people cannot directly digest grass. In areas where agriculturepeople cannot directly digest grass. In areas where agriculture is is not viable, this makes ecological sense.not viable, this makes ecological sense.

Nitrogen Cycle, Revisited

Carbon cycle, revisitedCarbon cycle, revisited

Ecological HierarchyEcological HierarchyOrganization of life according to number of Organization of life according to number of species and spatial scalespecies and spatial scaleIndividual SpeciesIndividual Species

IndividualIndividualPopulationPopulationMetapopulationMetapopulation

CommunityCommunityAssemblagesAssemblagesGuildsGuilds

Ecosystem: communities plus Ecosystem: communities plus trophictrophic interactionsinteractionsBiomes: ecosystems on a global scale, Biomes: ecosystems on a global scale, differentiated by levels of differentiated by levels of abioticabiotic inputs and inputs and primary productivityprimary productivityBiosphereBiosphere

EcosystemsEcosystems

Ecosystem: a selfEcosystem: a self--regulating regulating association of plants, animals and association of plants, animals and physical environmentphysical environmentEcology: the study of the various Ecology: the study of the various interactions between components interactions between components of the environmentof the environment

Ecosystem ComponentsEcosystem Components

Ecosystems have biotic and Ecosystems have biotic and abioticabiotic componentscomponentsAbioticAbiotic: :

solar energy inputsolar energy inputnutrient cyclesnutrient cycles

nitrogennitrogencarboncarbon

BioticBioticCommunitiesCommunities

an assemblage of interacting plants and animalsan assemblage of interacting plants and animalsCompetitionCompetitionMutualismsMutualisms

HabitatHabitatthe type of environment that a particular species lives in and ithe type of environment that a particular species lives in and is s adapted to.adapted to.

Some species are adapted to one type of habitatSome species are adapted to one type of habitat““habitat specialistshabitat specialists””

Some species are adapted to several habitatsSome species are adapted to several habitats““habitat generalistshabitat generalists””

Niche: the functional role a species plays in its communityNiche: the functional role a species plays in its communityHabitat nicheHabitat nicheTrophic niche: producer, consumer, decomposerTrophic niche: producer, consumer, decomposerReproductive nicheReproductive nicheCompetitive exclusion principleCompetitive exclusion principleAn ecosystem is most stable when all of its niches are filledAn ecosystem is most stable when all of its niches are filled

Range and DistributionRange and DistributionThe distribution of the The distribution of the abioticabiotic resources that resources that a species needs affects where that species a species needs affects where that species can occurcan occurClimatic factors are important determinants of Climatic factors are important determinants of rangerangeSpecies that are limited to one or a few areas Species that are limited to one or a few areas are referred to as endemicsare referred to as endemics

These species are often highly specialized to a These species are often highly specialized to a particular nicheparticular nicheOften the most efficient competitor for that niche, Often the most efficient competitor for that niche, but are susceptible to changebut are susceptible to change

Generalist species often have a much greater Generalist species often have a much greater spatial range than specialized species, and spatial range than specialized species, and are more tolerant of changeare more tolerant of change

Stability, Succession, DisturbanceStability, Succession, DisturbanceBasic ConceptsBasic Concepts

Stability: ability of a community to retain its species Stability: ability of a community to retain its species composition: most stable when all niches are filledcomposition: most stable when all niches are filled

Climax communityClimax communityResilience: ability of a community to recover its Resilience: ability of a community to recover its original species composition after a disturbanceoriginal species composition after a disturbanceBiodiversity: the number and abundance of species in Biodiversity: the number and abundance of species in an areaan areaDisturbance: an event that alters community Disturbance: an event that alters community composition, recomposition, re--allocates stored nutrients, and alters allocates stored nutrients, and alters nutrient pathwaysnutrient pathwaysSuccession: changes in species composition in a Succession: changes in species composition in a community over time as the community moves toward community over time as the community moves toward stability following a disturbancestability following a disturbance

Biodiversity and stabilityBiodiversity and stabilityHigh native biodiversity conveys ecosystem stabilityHigh native biodiversity conveys ecosystem stability

Prevent loss of energy and nutrients Prevent loss of energy and nutrients

DisturbanceDisturbanceWhen a disturbance is small in comparison to the When a disturbance is small in comparison to the community in question, the community quickly community in question, the community quickly reincorporates the disturbance and reestablishes reincorporates the disturbance and reestablishes stabilitystability

Example: tree fall, creating gaps in forest canopyExample: tree fall, creating gaps in forest canopy

When a disturbance is larger than a community When a disturbance is larger than a community and occurs relatively frequently, the type of and occurs relatively frequently, the type of disturbance structures the community compositiondisturbance structures the community composition

““Disturbance RegimeDisturbance Regime””Examples: Hurricanes, fire ecologyExamples: Hurricanes, fire ecology

When a disturbance is of similar spatial scale and When a disturbance is of similar spatial scale and occurs with a frequency comparable to succession occurs with a frequency comparable to succession rates, transformation of ecosystems can occurrates, transformation of ecosystems can occur

Ecological SuccessionEcological SuccessionPatch DynamicsPatch Dynamics

Seed banks (seeds already present at a location)Seed banks (seeds already present at a location)Dispersal (seeds transported into a location)Dispersal (seeds transported into a location)

Areas of infrequent disturbance are more likely to return to Areas of infrequent disturbance are more likely to return to original community compositionoriginal community compositionAreas of frequent disturbance will change composition Areas of frequent disturbance will change composition toward dispersible species from outside the patchtoward dispersible species from outside the patch

Terrestrial SuccessionTerrestrial SuccessionPrimary SuccessionPrimary Succession

Occurs in areas with no vegetationOccurs in areas with no vegetationexample: lava flowsexample: lava flowsexample: surface miningexample: surface mining

Species adapted to growing on little or no soil (lichens, mossesSpecies adapted to growing on little or no soil (lichens, mosses) ) are often the pioneer speciesare often the pioneer species

Secondary SuccessionSecondary SuccessionOccurs where disturbance leaves some vegetationOccurs where disturbance leaves some vegetationRapidly dispersing, opportunistic species are frequent pioneer Rapidly dispersing, opportunistic species are frequent pioneer speciesspecies

SuccessionSuccession

Fire EcologyFire EcologyA disturbance regimeA disturbance regimeFire is a Fire is a ““naturalnatural”” part of many ecosystemspart of many ecosystems

Especially in the western USEspecially in the western USLightning strikesLightning strikesNative American land managementNative American land management

created a created a ““parkpark--like landscapelike landscape”” that provided habitat for that provided habitat for gamegame

Many tree species are adapted to fire, and require Many tree species are adapted to fire, and require it to complete their reproductive cyclesit to complete their reproductive cycles

Fire suppression allowed accumulation of Fire suppression allowed accumulation of fuel, contributing to catastrophic firesfuel, contributing to catastrophic firesFire is now used as a management toolFire is now used as a management tool

Ecosystems and BiomesEcosystems and BiomesTerrestrial EcosystemsTerrestrial Ecosystems

selfself--regulating assemblages of plant and regulating assemblages of plant and animal species interacting with each other animal species interacting with each other and their and their abioticabiotic environmentenvironmentThe assemblage of plant species gives The assemblage of plant species gives each ecosystem its defining charactereach ecosystem its defining character

provides link between provides link between abioticabiotic and biotic and biotic components (distinguishes ecosystems from components (distinguishes ecosystems from communities)communities)provides habitat and nicheprovides habitat and niche

Biome: large, stable, terrestrial Biome: large, stable, terrestrial ecosystemecosystem

Classification based on dominant Classification based on dominant vegetationvegetation

forestforestsavannasavannashrublandshrublandgrasslandgrasslanddesertdeserttundratundra

EcotoneEcotone: transition zone between biomes: transition zone between biomesFormation classes: dominant vegetation Formation classes: dominant vegetation within the general biome classeswithin the general biome classes

Formation ClassesFormation ClassesEquatorial and Tropical Rainforest (ETR)Equatorial and Tropical Rainforest (ETR)Tropical Seasonal Forest and Scrub (Tropical Seasonal Forest and Scrub (TrSFTrSF))Tropical Savanna (TRS)Tropical Savanna (TRS)MidlatitudeMidlatitude Broadleaf and Mixed Forest (MBME)Broadleaf and Mixed Forest (MBME)NeedleleafNeedleleaf Forest and Montane Forest (NF/MF)Forest and Montane Forest (NF/MF)Temperate Rain Forest (Temperate Rain Forest (TeRTeR))Mediterranean Mediterranean ShrublandShrubland ((MShMSh))MidlatitudeMidlatitude Grasslands (Grasslands (MGrMGr))Warm Desert and SemiWarm Desert and Semi--desert (DBW)desert (DBW)Cold Desert and SemiCold Desert and Semi--desert (DBC)desert (DBC)Arctic and Alpine Tundra (AAT)Arctic and Alpine Tundra (AAT)(Ice)(Ice)

Equatorial and Tropical RainforestEquatorial and Tropical RainforestOccur in tropical areas that receive high amounts Occur in tropical areas that receive high amounts of rainfall regularly throughout the yearof rainfall regularly throughout the yearHigh net primary productivity and biomassHigh net primary productivity and biomassVertical arrangement of ecological nichesVertical arrangement of ecological niches

Emergent Layer: Intense sunlight, high temperatures, Emergent Layer: Intense sunlight, high temperatures, strong winds, low humiditystrong winds, low humidityCanopy Layer: 90% of species live here; epiphytes, Canopy Layer: 90% of species live here; epiphytes, lianas, primateslianas, primatesUnderstory: 2 Understory: 2 –– 15% of sunlight; dark, sparse, shade 15% of sunlight; dark, sparse, shade tolerant speciestolerant speciesForest Floor: Less than 2% light. Decomposing organic Forest Floor: Less than 2% light. Decomposing organic mattermatter

OxisolsOxisols, , UltisolsUltisolsRepresent approximately half of the worldRepresent approximately half of the world’’s s remaining forestsremaining forests

Tropical Seasonal Forest and ScrubTropical Seasonal Forest and ScrubAlso called Moist Deciduous forestAlso called Moist Deciduous forestOn the margins of tropical rainforestsOn the margins of tropical rainforestsSeasonal variation in rainfallSeasonal variation in rainfall

Tropical Savanna climateTropical Savanna climateTropical Monsoon climateTropical Monsoon climate

SemiSemi--deciduous treesdeciduous treeslose their leaves during the drylose their leaves during the dry--seasonseason

OxisolsOxisols, , UltisolsUltisols, , VertisolsVertisols, , AlfisolsAlfisolsCaatingaCaatinga (Brazil), Chaco (Paraguay and (Brazil), Chaco (Paraguay and Argentina), Argentina), brigalowbrigalow (Australia), (Australia), dornvelddornveld(South Africa)(South Africa)

Tropical SavannaTropical SavannaTransitional between tropical forests and semiTransitional between tropical forests and semi--arid tropical steppes and desertsarid tropical steppes and desertsMixture of grasslands and small trees and Mixture of grasslands and small trees and shrubsshrubsHerbivores that move in herds are characteristic Herbivores that move in herds are characteristic of landscapes that are wide openof landscapes that are wide openFireFire--ecology disturbance regimeecology disturbance regime

Rainfall only occurs with ITCZ (less than 6 months)Rainfall only occurs with ITCZ (less than 6 months)Dry conditions otherwiseDry conditions otherwise

xerophyticxerophytic vegetationvegetation

AlfisolsAlfisols, , UltisolsUltisols, , OxisolsOxisols

MidlatitudeMidlatitude Broadleaf and Mixed Broadleaf and Mixed ForestForest

Moist continental climatesMoist continental climateshumid subhumid sub--tropical hottropical hot--summer climatesummer climatemarine west coast climatesmarine west coast climatescool summer, winter drought climatecool summer, winter drought climate

Mixture of deciduous and evergreen Mixture of deciduous and evergreen speciesspeciesCommunity structure greatly altered by Community structure greatly altered by human activityhuman activityUltisolsUltisols, , AlfisolsAlfisols, some , some SpodosolsSpodosols

NeedleleafNeedleleaf Forest and Montane Forest and Montane ForestForest

Also called boreal forestsAlso called boreal forestsTaiga in in areas transitional to arctic or subarctic Taiga in in areas transitional to arctic or subarctic climatesclimates

Humid Humid microthermalmicrothermal climatesclimatesNeedleafNeedleaf forests not common in S. Hemisphereforests not common in S. HemisphereMontane forests found world wide (altitudinal Montane forests found world wide (altitudinal zonationzonation))

EvergreensEvergreensPine, spruce and firPine, spruce and fir

Characteristic faunaCharacteristic faunaBeaver, moose, snowshoe rabbit, lynx, wolverineBeaver, moose, snowshoe rabbit, lynx, wolverine

SpodosolsSpodosols, , HistosolsHistosols, some , some AlfisolsAlfisols

Temperate RainforestTemperate Rainforest

Mostly in the Pacific NW of N AmericaMostly in the Pacific NW of N AmericaRelatively low diversity of tree speciesRelatively low diversity of tree species

Tallest trees in the world: Giant Redwoods Tallest trees in the world: Giant Redwoods ((Sequoia Sequoia sempervirenssempervirens))Evergreens, some deciduousEvergreens, some deciduous

Extremely wet climateExtremely wet climateTongassTongass National Forest, AlaskaNational Forest, Alaska

The worldThe world’’s last pristine temperate s last pristine temperate rainforestrainforest

SpodosolsSpodosols, , InceptisolsInceptisols

Mediterranean Mediterranean ShrublandShrubland

Mediterranean dryMediterranean dry--summer climatesummer climatePolewardPoleward of subtropical high pressure of subtropical high pressure cellscells

Stable highStable high--pressure creates dry conditionspressure creates dry conditionsFire ecology disturbance regimeFire ecology disturbance regimeSclerophyllousSclerophyllous vegetationvegetation

hardy, drought resistant shrubs with deep hardy, drought resistant shrubs with deep roots and hard waxy leavesroots and hard waxy leaves

ChaparralChaparralAlfisolsAlfisols, , MollisolsMollisols

MidlatitudeMidlatitude GrasslandsGrasslands

The most heavily human modified biome The most heavily human modified biome mining of mining of MollisolsMollisols for agriculturefor agricultureVery little of this biome leftVery little of this biome left

Fauna also characterized by herding Fauna also characterized by herding herbivoresherbivoresPrairies of the Great Plains, Pampas of Prairies of the Great Plains, Pampas of ArgentinaArgentinaMollisolsMollisols, , AridisolsAridisols

Warm Desert and SemiWarm Desert and Semi--desertdesert

Subtropical high pressure cells create the Subtropical high pressure cells create the dry conditions in these areasdry conditions in these areasAtacama Desert, ChileAtacama Desert, ChileXerophyticXerophytic shrubs, succulents, thorn treesshrubs, succulents, thorn treesAridisolsAridisols, , EntisolsEntisols

Cold desert and Cold desert and SemidesertSemidesert

Higher latitudes than warm desertsHigher latitudes than warm desertsRainshadowsRainshadows and cold ocean currents and cold ocean currents influence the drynessinfluence the drynessSage brush and scrubSage brush and scrubMany were former shortMany were former short--grass regions, grass regions, transformed by intensive grazingtransformed by intensive grazingAridisolsAridisols, , EntisolsEntisols

Arctic and Alpine TundraArctic and Alpine Tundra

Northern hemisphere, bordering the Arctic Northern hemisphere, bordering the Arctic ocean North of 10ocean North of 10oo latitudelatitudeTundra vegetationTundra vegetation

Mosses, lichens, short grass, some small treesMosses, lichens, short grass, some small treesAlpine tundra: high altitude Alpine tundra: high altitude zonationzonation

FaunaFaunaLemmings, caribou, musk ox, arctic fox, polar bearLemmings, caribou, musk ox, arctic fox, polar bear

GellisolsGellisols, , InceptisolsInceptisols, , EntisolsEntisolspermafrostpermafrost