COMMUNITIES AND COMMUNITIES AND BIOMESBIOMES

Ch. 3.1: CommunitiesCh. 3.1: Communities

What is a community?What is a community? all the interacting all the interacting biotic biotic

factorsfactors in an area; all the in an area; all the different speciesdifferent species

How is a community How is a community different than an different than an ecosystem?ecosystem? Focuses on Focuses on bioticbiotic AND AND

abiotic factorsabiotic factors in an area in an area What are some limiting What are some limiting

factors that may have an factors that may have an effect on the living effect on the living organisms in this desert organisms in this desert community?community?

Limiting FactorsLimiting Factors SunlightSunlight TemperatureTemperature WaterWater Soil nutrients/chemistrySoil nutrients/chemistry # of other individuals # of other individuals

(shelter/food/protection)(shelter/food/protection) Food sourceFood source

What is tolerance?What is tolerance? Ability of an organism to withstand Ability of an organism to withstand

fluctuations of fluctuations of bioticbiotic and and abioticabiotic factorsfactors

What temperature range would you want to stay within for optimal plant growth?

What is the temperature range you need to stay within to ensure the plants survive? (This is the range of tolerance)

SuccessionSuccession It is a It is a processprocess By definition:By definition: orderly changesorderly changes & & speciesspecies

replacementreplacement of communities in ecosystems of communities in ecosystems You determine the type of succession by You determine the type of succession by

looking at the looking at the startingstarting pointpoint

SuccessionSuccession

Absolutely nothing.Absolutely nothing.

Primary SuccessionPrimary Succession Colonization of Colonization of

barren land (NEW barren land (NEW land w/ no soil)land w/ no soil)

Things used to be there, Things used to be there, but are gone.but are gone.

Secondary SuccessionSecondary Succession Soil is already presentSoil is already present There were living There were living

organisms on the land organisms on the land beforebefore

The steps of primary and secondary succession are identical with the exception of how they begin.

Ask yourself What was there before?

Primary SuccessionPrimary Succession = colonization of = colonization of barren land by communities of organismsbarren land by communities of organisms

1. New land is formed1. New land is formed

2. Pioneer 2. Pioneer species (ex. species (ex.

lichens) lichens) take holdtake hold

3. Decayed pioneer species 3. Decayed pioneer species build up and create soilbuild up and create soil

4. Once soil is formed, is 4. Once soil is formed, is the same as secondary the same as secondary successionsuccession

Secondary SuccessionSecondary Succession Sequence of changes after an existing Sequence of changes after an existing

community is destroyed/damaged/abandonedcommunity is destroyed/damaged/abandoned

Once soil has been Once soil has been established…established…

Succession follows the same pattern Succession follows the same pattern (whether it started as primary or (whether it started as primary or secondary)secondary)

Goes through a series of changes until a Goes through a series of changes until a stable, stable, climax communityclimax community is reached is reached

The The Indiana DunesIndiana Dunes are an example of are an example of primary successionprimary succession

BiomesBiomes

Ch. 3, Sec. 2Ch. 3, Sec. 2

What’s a Biome?What’s a Biome? Large group of ecosystems that share Large group of ecosystems that share

the same type of climax communitythe same type of climax community

Aquatic BiomesAquatic Biomes

Approx. 75% of Approx. 75% of Earth’s surface is Earth’s surface is covered by watercovered by water

Mostly salt waterMostly salt water

11. Marine Biomes. Marine Biomes = = oceans, can be very oceans, can be very shallow (surface of shallow (surface of ocean)ocean) or very or very deep deep (bottom of ocean)(bottom of ocean) Photic ZonePhotic Zone = portion = portion

of marine biome that of marine biome that is shallow enough for is shallow enough for sunlight to penetratesunlight to penetrate

Aphotic ZoneAphotic Zone = deep = deep water that never water that never receives sunlightreceives sunlight

2. Estuaries2. Estuaries = mixture of = mixture of freshwaterfreshwater & & ocean waterocean water; where rivers meet the ; where rivers meet the oceanocean

3. Intertidal Zone3. Intertidal Zone = portion of shoreline = portion of shoreline between high and low tidebetween high and low tide

4. Freshwater Biomes4. Freshwater Biomes = lakes, ponds, = lakes, ponds, rivers rivers

Terrestrial BiomesTerrestrial Biomes

Rainfall varies from biome to biome, Rainfall varies from biome to biome, resulting in different adaptations in resulting in different adaptations in speciesspecies

TundraTundra Cold temperaturesCold temperatures Low precipitation (less than 100cm/year)Low precipitation (less than 100cm/year) Layer of permafrost, only plants with shallow roots Layer of permafrost, only plants with shallow roots

can growcan grow Short growing seasonShort growing season

TaigaTaiga Cold, more precipitation than tundraCold, more precipitation than tundra Characteristic species of plant: Characteristic species of plant: conifers conifers

(trees that produce cones)(trees that produce cones) Soil has poor mineralsSoil has poor minerals

DesertDesert Less than 25cm of annual rainfallLess than 25cm of annual rainfall Tend to be very warm, but can be very Tend to be very warm, but can be very

cold as wellcold as well AdaptationsAdaptations for living in the desert for living in the desert

Plants = spine, waxy coating, toxins Plants = spine, waxy coating, toxins Animals = nocturnal activity, venom, require Animals = nocturnal activity, venom, require

less waterless water

GrasslandGrassland (prairies and savannas) (prairies and savannas) 25-75cm of rainfall25-75cm of rainfall Grasses are predominant speciesGrasses are predominant species Soil is rich in nutrientsSoil is rich in nutrients

Supports trees and shrubs Supports trees and shrubs

Usually near bodies of waterUsually near bodies of water Many grazing herbivoresMany grazing herbivores

Temperate ForestsTemperate Forests Trees lose their leaves each yearTrees lose their leaves each year Precipitation of 70-150cm /yearPrecipitation of 70-150cm /year

Rain ForestsRain Forests High level of precipitationHigh level of precipitation Warmer temperatureWarmer temperature High level of High level of biodiversitybiodiversity found in found in tropical tropical

& & temperate (moderate climate)temperate (moderate climate) areas areas

PracticePractice

How are organisms in the photic zone How are organisms in the photic zone and aphotic zone interdependent?and aphotic zone interdependent?

(Hint: Think about what grows in the (Hint: Think about what grows in the photic zone, what supports the base of photic zone, what supports the base of ecological pyramids? What happens if a ecological pyramids? What happens if a population of one species grows out of population of one species grows out of control?)control?)