Unit 1: EcologyUnit 1: Ecology

Chapters 2 through 5Chapters 2 through 5

EcologyEcology

The scientific study of interactions among The scientific study of interactions among organisms and their environments.organisms and their environments.

Aspects of Ecological StudyAspects of Ecological Study Biosphere Biosphere

Portion of earth that supports lifePortion of earth that supports life Abiotic FactorsAbiotic Factors

Non-living parts of an organism’s Non-living parts of an organism’s environmentenvironment

Biotic FactorsBiotic Factors

All the living organisms that inhabit an All the living organisms that inhabit an environment.environment.

Abiotic FactorsAbiotic Factors NON-LIVINGNON-LIVING parts of environment parts of environment Determine which species survive in an Determine which species survive in an

environmentenvironment Examples:Examples:

TemperatureTemperature LightLight MoistureMoisture SoilSoil Air CurrentsAir Currents

Biotic FactorsBiotic Factors

All All LIVINGLIVING parts of an environment parts of an environment Living things depend on one anotherLiving things depend on one another Need members of the species to Need members of the species to

reproducereproduce Competition for resourcesCompetition for resources Examples:Examples:

Five levels of Organization:Five levels of Organization:1.1. Organism –Organism – living thing living thing2.2. Populations –Populations – a) group of organisms of one species that a) group of organisms of one species that

interbreed and live in the same interbreed and live in the same geographical region geographical region

b) compete with each otherb) compete with each other3.3. Communities –Communities – Several populations in the same regionSeveral populations in the same regiona) Compete or rely on each othera) Compete or rely on each other

4.4. Ecosystems –Ecosystems –Made up of the all biotic and abiotic parts Made up of the all biotic and abiotic parts

of a region and their interactionsof a region and their interactionsTypes include: Types include:

terrestrial – land terrestrial – land aquatic – fresh wateraquatic – fresh watermarine – salt water (75% of Earth)marine – salt water (75% of Earth)

5.5. BiosphereBiosphereFrom High in the atmosphere to the From High in the atmosphere to the

bottoms of the oceansbottoms of the oceans

Organisms in EcosystemsOrganisms in Ecosystems HabitatHabitat – place where an organism lives – place where an organism lives Example:Example: NicheNiche – How an organism interacts with – How an organism interacts with

surrounding ecosystem; how it meets its surrounding ecosystem; how it meets its need for nutrients, shelter, reproduction, need for nutrients, shelter, reproduction, and survival. (The role or and survival. (The role or job of the job of the organismorganism))

Examples: Earthworms and soil, grass Examples: Earthworms and soil, grass and the hillside, bees and flowers.and the hillside, bees and flowers.

Types of Relationships between Types of Relationships between organisms:organisms:

SYMBIOSISSYMBIOSIS – a close and permanent – a close and permanent association among organisms of different association among organisms of different species.species.

Living RelationshipsLiving Relationships Feeding Relationships Feeding Relationships

Living RelationshipsLiving RelationshipsType of Type of RelationshipRelationship

Organism Organism AA

Organism Organism BB

ExampleExample

CommensalismCommensalism

MutualismMutualism

ParasitismParasitism

Predator/ PreyPredator/ Prey

benefits

benefits

benefits

benefits

harmed

neutral Spanish Moss/ Trees

Bee / Flower

Tick / Deer

How Organisms Obtain Energy:How Organisms Obtain Energy:Feeding RelationshipsFeeding Relationships

SunSun – ultimate source of energy – ultimate source of energy Producers (Autotrophs)Producers (Autotrophs) – – Produce own food from the energy of the Produce own food from the energy of the

sun (Photosynthesis)sun (Photosynthesis) Consumers (Heterotrophs)Consumers (Heterotrophs) – –Obtain nutrients by consuming other Obtain nutrients by consuming other

organismsorganisms

Types of HeterotrophsTypes of Heterotrophs

Carnivores -- Carnivores -- Scavengers-- Scavengers-- Herbivores --Herbivores -- Omnivores --Omnivores -- Decomposers -- Decomposers --

eats other animalsFeeds on already dead animals

eats plants

eats plants and animals

Breaks down and absorbsnutrients from dead &decayed plants & animals

Food ChainsFood Chains PathwayPathway showing how showing how MATTERMATTER and and

ENERGYENERGY move through the ecosystem.move through the ecosystem. AlgaeAlgae FishFish HeronHeron Arrow indicates direction of energy flowArrow indicates direction of energy flow Some energy is lost at each link in the Some energy is lost at each link in the

form of heat.form of heat. Formed by 3 – 5 links or steps (called Formed by 3 – 5 links or steps (called

Trophic Levels)Trophic Levels)

Trophic LevelsTrophic Levels

Link in a food chainLink in a food chain Many species can Many species can

occupy same leveloccupy same level A single species can A single species can

feed on several feed on several trophic levels.trophic levels.

Autotroph

1st order Heterotroph

2nd order Heterotroph

3rd order Heterotroph

Food WebsFood Webs Expresses all of the possible feeding Expresses all of the possible feeding

relationships in a communityrelationships in a community

Ecological PyramidsEcological Pyramids Ecological PyramidsEcological Pyramids

Shows energy used in an ecosystemShows energy used in an ecosystem Models the distribution of matter and Models the distribution of matter and

energy within an ecosystemenergy within an ecosystem Pyramid of Energy (HEAT)Pyramid of Energy (HEAT)

Only 10% of energy is transferred from Only 10% of energy is transferred from each succeeding trophic level each succeeding trophic level

Energy lost in the form of heat Energy lost in the form of heat (metabolism, building tissue, etc.)(metabolism, building tissue, etc.)

Cycles in NatureCycles in Nature

Matter is constantly recycled in the environment through several environmental cycles:

1. Water Cycle

2. Nitrogen Cycle

3. Carbon Cycle

4. Phosphorous Cycle

Water gets into air through: Water gets into air through: EvaporationEvaporation TranspirationTranspiration RespirationRespiration

Water gets out of air through precipitationWater gets out of air through precipitation

Carbon CycleCarbon Cycle

Animals or plants die and carbon is released by Animals or plants die and carbon is released by decomposers in the form of methane and decomposers in the form of methane and Carbon DioxideCarbon Dioxide

Carbon trapped in soil becomes fossil fuelsCarbon trapped in soil becomes fossil fuels Released back into atmosphere through Released back into atmosphere through

pollutionpollution AutotrophsAutotrophs (plants) (plants) take COtake CO22 from air from air

during photosynthesisduring photosynthesis (makes Oxygen (makes Oxygen and sugar)and sugar)

HeterotrophsHeterotrophs breath in Oxygen and breath in Oxygen and release COrelease CO22 back into the atmosphere back into the atmosphere during respirationduring respiration

Nitrogen CycleNitrogen Cycle

Air is 78% Nitrogen, but plants can’t use itAir is 78% Nitrogen, but plants can’t use it Lightning and bacteria convert nitrogen in Lightning and bacteria convert nitrogen in

air into a usable form (Nitrate) (NOair into a usable form (Nitrate) (NO22) in the ) in the

soilsoil Plants absorb the nitrogen through their roots Plants absorb the nitrogen through their roots

and use it to make proteinsand use it to make proteins Herbivores eat the nitrogen rich plants.Herbivores eat the nitrogen rich plants. Carnivores eat the HerbivoresCarnivores eat the Herbivores When Animals urinate or die they return the When Animals urinate or die they return the

nitrogen to the soilnitrogen to the soil

Chapter 3Chapter 3

Communities and Communities and BiomesBiomes

SuccessionSuccession Natural changes and Natural changes and

species replacements species replacements that take place in the that take place in the communities of an communities of an ecosystemecosystem

What would cause this?What would cause this?

Succession ContinuedSuccession Continued Occurs in stagesOccurs in stages Decades or even centuries to see this Decades or even centuries to see this

processprocess Primary SuccessionPrimary Succession – Colonization of – Colonization of

new sitesnew sites by communities of organisms. by communities of organisms. Ex. Lava flowEx. Lava flow

Pioneer SpeciesPioneer Species The first species to The first species to

occur in an area after occur in an area after primary succession primary succession has occurred.has occurred.

Lichen is a good Lichen is a good example of the 1example of the 1stst species to appearspecies to appear

Climax CommunityClimax Community

Stable, mature community that Stable, mature community that undergoes little or no change in species.undergoes little or no change in species.

Secondary SuccessionSecondary Succession Sequence of community changes that takes Sequence of community changes that takes

place after a place after a community is disruptedcommunity is disrupted by natural by natural disasters or human actionsdisasters or human actions

Occurs in an area that Occurs in an area that previously contained lifepreviously contained life Less time to reach a climax communityLess time to reach a climax community here here

again because life already existed.again because life already existed. Examples: Forest Fires, hurricanesExamples: Forest Fires, hurricanes

Primary or Secondary Succession?

Primary or Secondary Succession?

CommunitiesCommunities

Interacting populations of different Interacting populations of different speciesspecies

How would a green lawn be like a How would a green lawn be like a community?community?

Limiting FactorsLimiting Factors Environmental factorsEnvironmental factors that that affectaffect an an

organism’s organism’s ability to surviveability to survive Any Any aboiticaboitic or or bioticbiotic factor that restricts the factor that restricts the

existence, numbers, reproduction or existence, numbers, reproduction or distribution of organismsdistribution of organisms

Examples: Examples:

food availability, predators, and temperaturefood availability, predators, and temperature

Ranges of ToleranceRanges of Tolerance Population size varies Population size varies

according to its tolerance according to its tolerance for environmental change. for environmental change.

Examples: Examples:

Corn Crop affected by Corn Crop affected by ranges of temperature ranges of temperature

Cat fish tolerance to low Cat fish tolerance to low levels of oxygenlevels of oxygen

BiomesBiomes

Group of ecosystems with the same Group of ecosystems with the same climax communitiesclimax communities

Terrestrial (land) or Aquatic (water)Terrestrial (land) or Aquatic (water)

Marine BiomesMarine Biomes Largest amount of Largest amount of

biomass (living biomass (living material); mostly small material); mostly small organismsorganisms

Ecologists separate Ecologists separate them into zones called them into zones called photic, Aphoticphotic, Aphotic

Marine ZonesMarine Zones Photic ZonePhotic Zone – Shallow enough for sunlight – Shallow enough for sunlight

to penetrateto penetrate Aphotic ZoneAphotic Zone – Deep area of the water that – Deep area of the water that

never receives any light.never receives any light. EstuaryEstuary – Coastal body of water surrounded – Coastal body of water surrounded

by land in which fresh water and sea water by land in which fresh water and sea water mixmix

PlanktonPlankton Live in the photic zoneLive in the photic zone Base of all aquatic food chainsBase of all aquatic food chains Both small and large organisms eat Both small and large organisms eat

planktonplankton

Terrestrial BiomesTerrestrial Biomes TundraTundra TiagaTiaga DesertDesert GrasslandGrassland Temperate ForestTemperate Forest Tropical Rain ForestTropical Rain Forest

TundraTundra Treeless land with long summer days and Treeless land with long summer days and

short periods of winter sunlightshort periods of winter sunlight South of the north pole (permafrost)South of the north pole (permafrost) Topsoil is thin and can only support shallow Topsoil is thin and can only support shallow

rooted grasses and plantsrooted grasses and plants Mosquitoes are very commonMosquitoes are very common

TiagaTiaga Northern coniferous Northern coniferous

forest full of Spruce & forest full of Spruce & Fir treesFir trees

Stretches across Stretches across Canada, northern Canada, northern Europe and AsiaEurope and Asia

Warmer & wetter than Warmer & wetter than tundratundra

No permafrostNo permafrost

DesertDesert Driest biome Driest biome arid region with arid region with

limited plant limited plant growthgrowth

Plants are hardy Plants are hardy & waxy (reduces & waxy (reduces water loss)water loss)

Lizards, tortoises Lizards, tortoises and snakesand snakes

GRASSLANDSGRASSLANDS Large community Large community

covered with covered with grassesgrasses

Occurs in climates Occurs in climates with less water so with less water so forest can not forest can not survivesurvive

Yellowstone Yellowstone National park (Bison National park (Bison & deer)& deer)

Temperate ForestTemperate Forest 70-150 cm 70-150 cm

precipitation precipitation annuallyannually

Dominated by Dominated by hardwood trees hardwood trees that lose their that lose their foliage annuallyfoliage annually

Squirrel, mice Squirrel, mice rabbits & bearsrabbits & bears

Tropical Rain ForestTropical Rain Forest more species of organisms than any more species of organisms than any

other biomeother biome Warm temperatures, lush plant growthWarm temperatures, lush plant growth 200-600 cm of rain annually200-600 cm of rain annually Near the equatorNear the equator

Tropical Rain Forest ContinuedTropical Rain Forest Continued

Three areas of habitationThree areas of habitation

1.1. Ground levelGround level – leaves – leaves

2.2. Understory Understory – air is still, – air is still, humid, & dark, with lots of humid, & dark, with lots of insectsinsects

3.3. CanopyCanopy – Strong wind, – Strong wind, sunlight, rain. Monkeys and sunlight, rain. Monkeys and birds occupy this region.birds occupy this region.

Chapter 4Chapter 4

Population Population BiologyBiology

Population GrowthPopulation Growth

Increase in population size over timeIncrease in population size over time

Factors in Population SizeFactors in Population Size

ImmigrationImmigration

Movement Movement into a populationinto a population EmigrationEmigration

Movement Movement out of a populationout of a population DeathDeath BirthBirth

How fast do populations grow?How fast do populations grow?

Grow exponentiallyGrow exponentially – as population gets larger, – as population gets larger, it grows faster (more reproducing organisms)it grows faster (more reproducing organisms)

J-Shaped Curve:J-Shaped Curve:

Time

Populationsize

Can this continue forever?

Limits on the EnvironmentLimits on the Environment Limiting factors will stop a population from Limiting factors will stop a population from

increasing… causes an increasing… causes an S – shaped curveS – shaped curve.. Examples: Examples:

Food, Shelter, Sunlight, WaterFood, Shelter, Sunlight, Water Carrying CapacityCarrying Capacity – the number of one – the number of one

species that an environment can support.species that an environment can support.

Time

Populationsize

Carrying Capacity

Reproductive PatternsReproductive Patterns

Rapid Life HistoryRapid Life History

Vs.Vs.

Long Life HistoryLong Life History

Rapid Life HistoryRapid Life History

Organisms in Organisms in unpredictable environmentsunpredictable environments.. Small bodies, mature rapidly, reproduce Small bodies, mature rapidly, reproduce

early, and have short life spans.early, and have short life spans. Lots of offspringLots of offspring Examples:Examples:

mouse, mosquito, fly, weeds, etc.mouse, mosquito, fly, weeds, etc.

Long Life HistoryLong Life History

Organisms in Organisms in stable environmentsstable environments Large bodies, reproduce and mature Large bodies, reproduce and mature

slowly, long-lived, maintain population slowly, long-lived, maintain population near carrying capacitynear carrying capacity

Few offspringFew offspring Examples:Examples:

Humans, elephant, horse, tree, etc.Humans, elephant, horse, tree, etc.

Environmental LimitsEnvironmental Limits Limits that affect population size and growthLimits that affect population size and growth Density-dependent factorsDensity-dependent factors – – Depends on size of the populationDepends on size of the population.. Disease, competition, parasitism, foodDisease, competition, parasitism, food Density-independent factorsDensity-independent factors – – Aren’t dependent on the size of the Aren’t dependent on the size of the

populationpopulation Temperature, drought, flood, habitat Temperature, drought, flood, habitat

disruptiondisruption

Organism Interactions Limit Organism Interactions Limit Population SizePopulation Size

Predation – Predation –

cat hunting mousecat hunting mouse Competition –Competition –

sheep and goats for foodsheep and goats for food Crowding and Stress –Crowding and Stress –

if too many cows are kept in a pasture they will if too many cows are kept in a pasture they will become stressed (Not enough space to roam become stressed (Not enough space to roam around)around)

Biological DiversityBiological Diversityandand

ConservationConservation

Chapter 5Chapter 5

BiodiversityBiodiversity Variety of lifeVariety of life in an area in an area Measured by the number of species in an Measured by the number of species in an

areaarea

Important because…Important because…

1.1. Beauty of NatureBeauty of Nature

2.2. Life depends on LifeLife depends on Life

3.3. Fulfills Human needs: oxygen, food, Fulfills Human needs: oxygen, food, medicinesmedicines

Loss of BiodiversityLoss of Biodiversity

Species can become endangered or extinctSpecies can become endangered or extinct It can occur through It can occur through Habitat AlterationHabitat Alteration

Climate changes Climate changes

Human activityHuman activity

Introduction of Non-native speciesIntroduction of Non-native species