Post on 12-Jan-2016
Chapter 6Chapter 6Major Ecosystems of the WorldMajor Ecosystems of the World
Overview of Chapter 6Overview of Chapter 6
Earth’s Major BiomesEarth’s Major Biomes Aquatic EcosystemsAquatic Ecosystems
Freshwater ecosystemsFreshwater ecosystems EstuariesEstuaries
Marine EcosystemsMarine Ecosystems Interaction of Life Zones and HumansInteraction of Life Zones and Humans
Earth’s Major BiomesEarth’s Major Biomes
BiomeBiome A large, relatively distinct terrestrial A large, relatively distinct terrestrial
region with a similar climate soil, plants, region with a similar climate soil, plants, and animals, regardless of where it and animals, regardless of where it occurs in the worldoccurs in the world
Nine major biomes Nine major biomes Location of each biome is primarily Location of each biome is primarily
determined by:determined by: Temperature (varies with both latitude Temperature (varies with both latitude
and elevation)and elevation) PrecipitationPrecipitation
TundraTundra
Treeless biome in the Treeless biome in the far north with harsh, far north with harsh, cold winters and cold winters and extremely short extremely short summerssummers
PrecipitationPrecipitation 10–25 cm/yr10–25 cm/yr
TemperatureTemperature Short growing seasonShort growing season 50–160 days50–160 days
Low species Low species richnessrichness Veg is mostly Veg is mostly
grasses and sedgesgrasses and sedges Very simple food Very simple food
webweb Low primary Low primary
productivityproductivity
TundraTundra
Nutrient poor soils with little organic Nutrient poor soils with little organic materialmaterial Permafrost presentPermafrost present
Boreal ForestsBoreal Forests
A region of coniferous forests in the A region of coniferous forests in the northern hemispherenorthern hemisphere Just south of tundraJust south of tundra
Covers 11% of Earth’s Covers 11% of Earth’s
landland Growing SeasonGrowing Season
A little longer thanA little longer than
tundratundra PrecipitationPrecipitation
~ 50 cm/yr~ 50 cm/yr
White spruceWhite spruce Balsam firBalsam fir Eastern larchEastern larch
Mostly small Mostly small animals and animals and migrating birdsmigrating birds
Some large Some large animals are animals are presentpresent Wolves, bear, Wolves, bear,
moosemoose
Boreal ForestsBoreal Forests Soils are acidic and mineral poorSoils are acidic and mineral poor Vegetation comprised of drought Vegetation comprised of drought
resistant conifersresistant conifers
Temperate RainforestTemperate Rainforest
Coniferous biome with cool weather, Coniferous biome with cool weather, dense fog and high precipitationdense fog and high precipitation Ex: Northwest USEx: Northwest US
PrecipitationPrecipitation > 127 cm/yr> 127 cm/yr Heaviest in winterHeaviest in winter
TemperatureTemperature Winters are mildWinters are mild Summers are coolSummers are cool
Temperate RainforestTemperate Rainforest Soils are nutrient-poor, but high in organic Soils are nutrient-poor, but high in organic
material (dropped needles)material (dropped needles) Cool temperatures slow decompositionCool temperatures slow decomposition
Dominant VegetationDominant Vegetation Large evergreen treesLarge evergreen trees Old-growth forestOld-growth forest
Variety of cool Variety of cool
climate animal lifeclimate animal life Very high speciesVery high species
richnessrichness Heavily loggedHeavily logged
Temperature Deciduous Temperature Deciduous ForestsForests Forest biome that Forest biome that
occurs in temperate occurs in temperate areas with a areas with a moderate amount moderate amount of precipitationof precipitation
PrecipitationPrecipitation 75–150 cm/yr75–150 cm/yr
TemperatureTemperature SeasonalitySeasonality Hot summers and Hot summers and
cold winterscold winters
Temperate Deciduous Temperate Deciduous ForestForest Topsoil is rich in organic Topsoil is rich in organic
material and underlain by material and underlain by clayclay
Vegetation is primarily Vegetation is primarily deciduousdeciduous Oak, maple, beechOak, maple, beech
AnimalsAnimals Deer, bear and small Deer, bear and small
animalsanimals Most of this biome land Most of this biome land
area has been area has been regenerated after farming regenerated after farming & timber harvest& timber harvest
GrasslandGrassland Grasslands with hot summers, cold Grasslands with hot summers, cold
winters and too little precipitation to winters and too little precipitation to support treessupport trees
PrecipitationPrecipitation 25–75 cm/yr25–75 cm/yr
Tall grass prairiesTall grass prairies Short grass prairiesShort grass prairies 90% of this biome90% of this biome
has been lost tohas been lost to
farmlandfarmland
GrasslandGrassland Soil has thick, Soil has thick,
organic material rich organic material rich organic horizonorganic horizon
Periodic fires keep Periodic fires keep the dominant the dominant vegetationvegetation
AnimalsAnimals Once covered with Once covered with
bison - no longer truebison - no longer true Smaller animals are Smaller animals are
still present (ex: still present (ex: prairie dogs)prairie dogs)
ChaparralChaparral
Also called a Mediterranean ClimateAlso called a Mediterranean Climate Ex: Southern CaliforniaEx: Southern California Ex: GreeceEx: Greece
TemperatureTemperature Mild, moist wintersMild, moist winters Hot, dry summersHot, dry summers
Frequent firesFrequent fires
ChaparralChaparral
Soil is thin and Soil is thin and often not fertileoften not fertile
VegetationVegetation Dense growth of Dense growth of
evergreen shrubsevergreen shrubs Lush during the Lush during the
growing seasongrowing season AnimalsAnimals
Mule deer, Mule deer, chipmunks, many chipmunks, many species of birdsspecies of birds
DesertsDeserts
Biome where lack Biome where lack of precipitation of precipitation limits plant growthlimits plant growth
TemperatureTemperature Can very greatly in Can very greatly in
24-hr period, as 24-hr period, as well as yearly well as yearly (based on location)(based on location)
PrecipitationPrecipitation < 25 cm/yr< 25 cm/yr
DesertsDeserts Soils low in nutrients and high in Soils low in nutrients and high in
saltssalts Vegetation sparseVegetation sparse
cactus and sagebrushcactus and sagebrush Animals are very small to regulate Animals are very small to regulate
temperaturetemperature
SavannaSavanna
Tropical grassland Tropical grassland with widely with widely scattered treesscattered trees
TemperatureTemperature Varies little Varies little
throughout the yearthroughout the year PrecipitationPrecipitation
Seasons regulated Seasons regulated by precipitation, not by precipitation, not temperaturetemperature
76–150 cm/yr76–150 cm/yr
SavannaSavanna Soil low in nutrients due to leachingSoil low in nutrients due to leaching VegetationVegetation
Wide expanses of grass, occasional Acacia Wide expanses of grass, occasional Acacia treestrees
Have fire adaptiveHave fire adaptivecharacteristicscharacteristics
AnimalsAnimals Herds of hoofedHerds of hoofed
animalsanimals Large predators -Large predators -
lions, hyenas, etc.lions, hyenas, etc.
Tropical RainforestTropical Rainforest
Lush, species-rich Lush, species-rich biome that occurs biome that occurs where climate is where climate is warm and moist warm and moist throughout the yearthroughout the year
PrecipitationPrecipitation 200–450 cm/yr200–450 cm/yr
Very productive Very productive biomebiome
Most species-rich Most species-rich biomebiome
Tropical RainforestTropical Rainforest
Ancient, weathered, Ancient, weathered, nutrient-poor soilnutrient-poor soil Nutrients tied up in Nutrients tied up in
vegetation, not soilvegetation, not soil VegetationVegetation
3 distinct canopy3 distinct canopylayerslayers
AnimalsAnimals Most abundant Most abundant
insect, reptiles and insect, reptiles and amphibians on earthamphibians on earth
Vertical ZonationVertical Zonation
Increasing Increasing in elevation in elevation has similar has similar effect on effect on ecosystem ecosystem as traveling as traveling to higher to higher latitudeslatitudes
Aquatic EcosystemAquatic Ecosystem Fundamental DivisionFundamental Division
FreshwaterFreshwater SaltwaterSaltwater
Aquatic Ecosystems also affected byAquatic Ecosystems also affected by Dissolved oxygen level, light penetration, Dissolved oxygen level, light penetration,
pH, presence/absence of currentspH, presence/absence of currents Three main ecological categories of Three main ecological categories of
organismsorganisms Plankton - free floatingPlankton - free floating Nekton - strong swimmingNekton - strong swimming Benthos - bottom dwellingBenthos - bottom dwelling
Freshwater EcosystemsFreshwater Ecosystems
Includes:Includes: Rivers and streamsRivers and streams Lakes and pondsLakes and ponds Marshes and swampsMarshes and swamps
Represent 2% of earth’s surfaceRepresent 2% of earth’s surface Assist in recycling water back to the Assist in recycling water back to the
oceansoceans
Rivers and StreamsRivers and Streams
Lakes and PondsLakes and Ponds
Body of freshwater that does not flowBody of freshwater that does not flow Three zonesThree zones
LittoralLittoral LimneticLimnetic ProfundalProfundal
Experience thermal stratification Experience thermal stratification (depending on depth)(depending on depth)
Lakes and PondsLakes and Ponds
Littoral Zone - shallow water area along the Littoral Zone - shallow water area along the shoreshore
Limnetic Zone - open water beyond the Limnetic Zone - open water beyond the littoral zonelittoral zone
Profundal Zone - beneath the limnetic zone Profundal Zone - beneath the limnetic zone of deep lakesof deep lakes
Thermal StratificationThermal Stratification
Temperature Temperature changes sharply changes sharply with depthwith depth
ThermoclineThermocline Temperature Temperature
transition transition between warmer between warmer surface water surface water and colder water and colder water at depthat depth
Only present in Only present in warm monthswarm months
Fall TurnoverFall Turnover
Marshes and SwampsMarshes and Swamps
Lands that shallow, Lands that shallow, fresh water covers fresh water covers for at least part of for at least part of the yearthe year
Were once regularly Were once regularly filled infilled in More recently their More recently their
ecosystem services ecosystem services have been better have been better recognizedrecognized Flood protection, Flood protection,
water filtering, etc.water filtering, etc.
EstuariesEstuaries Where freshwater and saltwater mixWhere freshwater and saltwater mix Highly variable environmentHighly variable environment
Temperature, salinity, depth of light Temperature, salinity, depth of light penetrationpenetration
Highly productiveHighly productive Nutrients transportedNutrients transported
from landfrom land High level of lightHigh level of light
penetrates shallow waterpenetrates shallow water Plants providePlants provide
photosynthetic carpetphotosynthetic carpet
Marine EcosystemsMarine Ecosystems
Subdivided into life zonesSubdivided into life zones Intertidal zoneIntertidal zone Benthic zoneBenthic zone Pelagic environmentPelagic environment
Neritic ProvinceNeritic Province Oceanic ProvinceOceanic Province
Marine EcosystemsMarine Ecosystems
Intertidal ZoneIntertidal Zone
Area of shoreline between low and high Area of shoreline between low and high tidestides
Benthic ZoneBenthic Zone
Ocean floor, extending from tidal zone Ocean floor, extending from tidal zone to deep sea trenchesto deep sea trenches
Sediment is mostly mudSediment is mostly mud Burrowing worms and clamsBurrowing worms and clams
Three zoneThree zone Bathyal: 200m–4000m deepBathyal: 200m–4000m deep Abyssal: 4000m–6000m deepAbyssal: 4000m–6000m deep Hadal: 6000m–bottom of deep sea Hadal: 6000m–bottom of deep sea
trenchestrenches
Productive Benthic Productive Benthic CommunitiesCommunities Seagrass BedsSeagrass Beds
Present to depth of 10 mPresent to depth of 10 m Provide food and habitat to ecosystemProvide food and habitat to ecosystem
Kelp ForestKelp Forest 60 m long brown algae found off rocky shores60 m long brown algae found off rocky shores Large BiodiversityLarge Biodiversity
Coral ReefsCoral Reefs Built from accumulated layers of CaCOBuilt from accumulated layers of CaCO33
Colonies of millions of tiny coral animalsColonies of millions of tiny coral animals Found in shallow warm waterFound in shallow warm water Most diverse of all marine environmentsMost diverse of all marine environments
Left:Left:
SeagrassSeagrass
BedBed
Right:Right:
Kelp Kelp ForestForest
Productive Benthic Productive Benthic CommunitiesCommunities
Coral Reef EnvironmentsCoral Reef Environments
Three types of Three types of coral reefscoral reefs Fringing reef - Fringing reef -
directly attach to directly attach to continent - no continent - no lagoonlagoon
Atoll - circular Atoll - circular reef in a lagoonreef in a lagoon
Barrier reef - Barrier reef - separates lagoon separates lagoon from oceanfrom ocean
Human Impact on Coral Human Impact on Coral ReefsReefs SedimentationSedimentation
From clear-cutting upstreamFrom clear-cutting upstream OverfishingOverfishing Coral bleachingCoral bleaching Mining of corals as building materialsMining of corals as building materials Runoff pollutionRunoff pollution
Pelagic EnvironmentPelagic Environment
All the open ocean waterAll the open ocean water Two main divisionsTwo main divisions
Neritic ProvinceNeritic Province Water that overlies the continental shelf (to Water that overlies the continental shelf (to
depth of 200 m)depth of 200 m) Organisms are all floaters or swimmersOrganisms are all floaters or swimmers
Oceanic ProvinceOceanic Province Water that overlies depths greater than 200 mWater that overlies depths greater than 200 m Organisms are filter feeders, scavengers and Organisms are filter feeders, scavengers and
predatorspredators
Human Impacts on the Human Impacts on the OceanOcean