Ecosystems Ecosystems and and

CommunitiesCommunities

What is Climate?What is Climate?

WeatherWeather is the day-to-day condition is the day-to-day condition of Earth’s atmosphere at a particular of Earth’s atmosphere at a particular time and placetime and place

ClimateClimate refers to the average, year- refers to the average, year-after-year conditions of temperature after-year conditions of temperature and precipitation in a particular and precipitation in a particular region.region.

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The Greenhouse EffectThe Greenhouse Effect What is it?What is it?

A natural situation A natural situation in which heat is in which heat is retained by a layer retained by a layer of greenhouse of greenhouse gases.gases.

What causes it?What causes it?

Carbon dioxide, Carbon dioxide, methane, water methane, water vapor, and a few vapor, and a few other atmospheric other atmospheric gases trap heat gases trap heat energy and energy and maintain Earth’s maintain Earth’s temperature range.temperature range.

Effects of Latitude on Effects of Latitude on ClimateClimate

Because earth is a sphere that is tilted, Because earth is a sphere that is tilted, solar radiation hits Earth at different solar radiation hits Earth at different anglesangles This creates 3 main climate zonesThis creates 3 main climate zones

Polar zones = cold zones at the polesPolar zones = cold zones at the poles Tropical zones = warm zones around the Tropical zones = warm zones around the

equatorequator Temperate zones = in between the polar Temperate zones = in between the polar

and tropical zones, vary from hot to cold and tropical zones, vary from hot to cold throughout the yearthroughout the year

Heat Transport in the Heat Transport in the BiosphereBiosphere

The unequal heating of earths The unequal heating of earths surface drives winds and ocean surface drives winds and ocean currents spreading heatcurrents spreading heat

Warm air at the equator rises, cool air at Warm air at the equator rises, cool air at the poles sinks creating wind currentsthe poles sinks creating wind currents

Warm water at the equator rises, cool Warm water at the equator rises, cool water at the poles sinks creating ocean water at the poles sinks creating ocean currentscurrents

What Shapes an What Shapes an Ecosystem?Ecosystem?

Biotic and Abiotic FactorsBiotic and Abiotic Factors NicheNiche Community InteractionsCommunity Interactions Ecological SuccessionEcological Succession

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Biotic FactorsBiotic Factors

Ecosystems are influenced by a Ecosystems are influenced by a combination of biological and physical combination of biological and physical factors.factors.

Biotic FactorsBiotic Factors are the biological (living) are the biological (living) influences on organisms within an influences on organisms within an ecosystem.ecosystem.

Examples: all living things it might interact Examples: all living things it might interact with, birds, trees, mushrooms, bacteria…with, birds, trees, mushrooms, bacteria…

Abiotic FactorsAbiotic Factors Abiotic FactorsAbiotic Factors are the physical (nonliving) are the physical (nonliving)

factors that shape ecosystemsfactors that shape ecosystems

Examples: temperature, precipitation, Examples: temperature, precipitation, humidity, wind, nutrient availability, soil humidity, wind, nutrient availability, soil type, sunlight.type, sunlight.

Together, biotic and abiotic factors Together, biotic and abiotic factors determine the survival and growth of an determine the survival and growth of an organism and the productivity of the organism and the productivity of the ecosystem in which the organism lives.ecosystem in which the organism lives.

The NicheThe Niche A A nicheniche is the full range of physical and is the full range of physical and

biological conditions in which an organism biological conditions in which an organism lives and the way in which the organism lives and the way in which the organism uses those conditions.uses those conditions.

A niche includes the type of food it eats, A niche includes the type of food it eats, how it obtains it, and which other species how it obtains it, and which other species use the organism as food. It also includes use the organism as food. It also includes the physical conditions it requires to survive the physical conditions it requires to survive and it includes when and how it reproduces.and it includes when and how it reproduces.

Everything an organism does to Everything an organism does to survive!survive!

The NicheThe Niche No two species can No two species can

share the same share the same niche in the same niche in the same habitat.habitat.

Different species Different species can occupy niches can occupy niches that are very that are very similarsimilar

ExampleExample

Three species of Three species of North American North American warblers live in the warblers live in the same spruce trees, same spruce trees, but they feed at but they feed at different elevations different elevations and on different and on different parts of the trees.parts of the trees.

Community Community InteractionsInteractions

Community interactions, such as Community interactions, such as competition, predation, and competition, predation, and various forms of symbiosis, can various forms of symbiosis, can powerfully affect an ecosystem.powerfully affect an ecosystem.

CompetitionCompetition CompetitionCompetition occurs when organisms of the occurs when organisms of the

same or different species attempt to use an same or different species attempt to use an ecological resource in the same place at the ecological resource in the same place at the same time.same time.

ResourceResource refers to any necessity of life, such refers to any necessity of life, such as water, nutrients, light, food, or space.as water, nutrients, light, food, or space.

TheThe competitive exclusion principlecompetitive exclusion principle, , states states that no two species can occupy the same that no two species can occupy the same niche in the same habitat at the same time.niche in the same habitat at the same time.

PredationPredation

PredationPredation is an interaction in which is an interaction in which one organism captures and feeds on one organism captures and feeds on another organism.another organism.

The predator is the organism that The predator is the organism that does the killing.does the killing.

The The preyprey is the food organism, the is the food organism, the organism that is being hunted/eaten.organism that is being hunted/eaten.

Predation Predation

SymbiosisSymbiosis is any relationship in is any relationship in which two species live closely which two species live closely together.together.

Symbiosis means “living together”Symbiosis means “living together”

Three main classes of symbiosis:Three main classes of symbiosis: MutualismMutualism CommensalismsCommensalisms ParasitismParasitism

SymbiosisSymbiosis

MutualismMutualism

MutualismMutualism is when both species is when both species benefit, they help each other.benefit, they help each other.

Example: many flowers depend on Example: many flowers depend on certain species of insects to pollinate certain species of insects to pollinate them. them.

The flowers provide the insects with The flowers provide the insects with food (nectar or pollen) and the food (nectar or pollen) and the insects help the flowers reproduce.insects help the flowers reproduce.

MutualismMutualism

CommensalismsCommensalisms

CommensalismCommensalism is when one member is when one member of the association benefits and the other is of the association benefits and the other is neither helped nor harmed.neither helped nor harmed.

Example: barnacles attach themselves to a Example: barnacles attach themselves to a whale’s skin.whale’s skin.

The barnacles don’t help or hurt the whale, The barnacles don’t help or hurt the whale, but the barnacles benefit because as the but the barnacles benefit because as the whale swims, the constantly moving water whale swims, the constantly moving water carries the food the barnacles eat to them.carries the food the barnacles eat to them.

CommensalismsCommensalisms

ParasitismParasitism

ParasitismParasitism is when one organism lives is when one organism lives on or inside another organism and harms it.on or inside another organism and harms it.

The parasite obtains all or part of its The parasite obtains all or part of its nutritional needs from the other organism, nutritional needs from the other organism, called the hostcalled the host

Example: tape worms live in the intestine of Example: tape worms live in the intestine of mammals, Fleas, ticks , and lice live on the mammals, Fleas, ticks , and lice live on the bodies of mammals, feeding on the blood bodies of mammals, feeding on the blood and skin of the hostand skin of the host

ParasitismParasitism

Ecological SuccessionEcological Succession

Ecosystems are constantly changing in Ecosystems are constantly changing in response to natural and human disturbances.response to natural and human disturbances.

As an ecosystem changes, older inhabitants As an ecosystem changes, older inhabitants gradually die out and new organisms move gradually die out and new organisms move in, causing further changes in the in, causing further changes in the community.community.

These predictable changes that occurs in a These predictable changes that occurs in a community over time is called community over time is called Ecological Ecological SuccessionSuccession..

Ecological SuccessionEcological Succession

Succession that occurs where no soil Succession that occurs where no soil exists is called exists is called primary successionprimary succession..

When a disturbance of some kind When a disturbance of some kind changes an existing community changes an existing community without removing the soil, then without removing the soil, then secondary successionsecondary succession can take place. can take place.

Primary SuccessionPrimary SuccessionStagesStages

The first species to populate the area The first species to populate the area are called are called pioneer speciespioneer species. It is . It is usually lichens.usually lichens.

Lichens break down rock, as they die Lichens break down rock, as they die they add organic material to help they add organic material to help form soil in which plants can grow.form soil in which plants can grow.

After lichens, mosses appear, and After lichens, mosses appear, and grasses take root, then seedlings and grasses take root, then seedlings and shrubs can start to sprout.shrubs can start to sprout.

Lichens and Mosses Lichens and Mosses (pioneer species)(pioneer species)

SuccessionSuccession

Secondary SuccessionSecondary Succession

Secondary Secondary succession succession happens when happens when land is cleared and land is cleared and plowed for farming plowed for farming and is abandoned and is abandoned or when wildfire or when wildfire burns woodlands.burns woodlands.