ecosystem structure. the nature of ecology the study of the interrelationships between plants and...

Ecosystem StructureEcosystem Structure

The Nature of EcologyThe Nature of Ecology

The study of the interrelationships between plants and animals and their physical environment

The study of the interrelationships between plants and animals and their physical environment

OrganismsOrganisms

PopulationsPopulations

CommunitiesCommunities

EcosystemsEcosystems

BiosphereBiosphere

How do Ecologists learn about natural systems?How do Ecologists learn about natural systems?

Field researchField research

Remote sensingRemote sensing

Geographic information systems (GIS)Geographic information systems (GIS)

Laboratory researchLaboratory research

Systems analysis (mathematical,computer models)

Systems analysis (mathematical,computer models)

Matter: anything that has mass and occupies spaceMatter: anything that has mass and occupies space

ElementsElements

CompoundsCompounds

MixturesMixtures

MoleculesMolecules

The States of MatterThe States of Matter

SolidSolid

LiquidLiquid

GasGas

Energy: the ability to do workEnergy: the ability to do work

Kinetic energy Kinetic energy Potential energyPotential energyHeatHeat

The Law of Conservation of MatterThe Law of Conservation of Matter

Matter cannot be created nordestroyed

Matter cannot be created nordestroyed

Matter only changes formMatter only changes form

There is no “away”There is no “away”

Laws Governing Energy ChangesLaws Governing Energy Changes

Energy is neither created nor destroyed Energy is neither created nor destroyed

Energy only changes form Energy only changes form

You can’t get something for nothing You can’t get something for nothing

First Law of Thermodynamics (Energy)First Law of Thermodynamics (Energy)

ENERGY IN = ENERGY OUTENERGY IN = ENERGY OUT

Laws Governing Energy ChangesLaws Governing Energy Changes

Second Law of ThermodynamicsSecond Law of Thermodynamics

In every transformation, some energy is converted to heat (lower quality)

In every transformation, some energy is converted to heat (lower quality)

You cannot break even in terms of energy quality

You cannot break even in terms of energy quality

Connections: Matter and Energy Laws and Environmental ProblemsConnections: Matter and Energy Laws and Environmental Problems

High-throughput (waste) economy High-throughput (waste) economy

Matter-recycling economy Matter-recycling economy

Low-throughputeconomy

Low-throughputeconomy

Ecosystem StructureEcosystem StructureEcosystem StructureEcosystem Structure

• Ecosystems have two general Ecosystems have two general categories of components:categories of components:

– BioticBiotic - living organisms - living organisms

– AbioticAbiotic - nonliving - nonliving

The Biotic Components of EcosystemsThe Biotic Components of Ecosystems

Producers(autotrophs)

Producers(autotrophs)

- Photosynthesis- Photosynthesis

Consumers(heterotrophs)

Consumers(heterotrophs)

- Aerobic respiration- Aerobic respiration

Decomposers Decomposers

ConsumersConsumers

• Primary, secondary, tertiary, etc.Primary, secondary, tertiary, etc.

• HerbivoreHerbivore - plant eater - plant eater

• CarnivoreCarnivore - meat eater - meat eater

• OmnivoreOmnivore - mixed plant/animal diet - mixed plant/animal diet

The Abiotic Components of EcosystemsThe Abiotic Components of Ecosystems

1) Outside energy source1) Outside energy source

2) Physical factors that determine2) Physical factors that determine weather, climateweather, climate

3) Chemicals essential for life3) Chemicals essential for life

Outside Energy SourceOutside Energy Source

PowersPowersphotosynthesisphotosynthesis

Warms earthWarms earth

Powers waterPowers watercyclecycle

Physical factors that determinePhysical factors that determineweather, climateweather, climatePhysical factors that determinePhysical factors that determineweather, climateweather, climate

HeatHeat

WindWind

PrecipitationPrecipitation

TopographyTopography

HeatHeatHeatHeat

LocationLocation

ReflectionReflection

RetentionRetention

Wind and PrecipitationWind and PrecipitationWind and PrecipitationWind and Precipitation• Uneven heatingUneven heating

• Ascending, Ascending, descending air descending air massesmasses

Slide 13Slide 13Slide 13Slide 13Slide 13

Moist surface warmed by sun

Flows toward low pressure,picks up moisture and heat

Warm,dry air

Hot, wetair

Falls, is compressed, warms Rises, expands, cools

Heat releasedradiates to space

LOWPRESSURE

HIGHPRESSURE

Cool, dryair

Condensationand

precipitation

HIGHPRESSURE

HIGHPRESSURE

LOWPRESSURE

LOWPRESSURE

Figure 6-10Page 117

ModifiersModifiersModifiersModifiers

• Rotation of the Rotation of the globeglobe

• Geologic Geologic featuresfeatures

Rain ShadowsRain ShadowsRain ShadowsRain Shadows

Lake-effect PrecipitationLake-effect PrecipitationLake-effect PrecipitationLake-effect Precipitation

Chemicals Essential for LifeChemicals Essential for LifeChemicals Essential for LifeChemicals Essential for Life

• Elements and Elements and compoundscompounds

• Recycled Recycled between biotic between biotic and abiotic partsand abiotic parts

Organic vs. InorganicOrganic vs. InorganicOrganic vs. InorganicOrganic vs. Inorganic

• Organic compounds made by living thingsOrganic compounds made by living things– e.g., proteins, fats, DNAe.g., proteins, fats, DNA

• Inorganic compounds produced by biotic Inorganic compounds produced by biotic or abiotic processesor abiotic processes– e.g., water, carbon dioxide

Limiting Factor PrincipleLimiting Factor PrincipleLimiting Factor PrincipleLimiting Factor Principle

• Too much or too little of any abiotic factor can Too much or too little of any abiotic factor can limit or prevent growth of a population, even if limit or prevent growth of a population, even if all other factors are optimal for that population.all other factors are optimal for that population.

• Single factor most over-abundant or deficient in Single factor most over-abundant or deficient in an ecosystem determines presence/absence of an ecosystem determines presence/absence of specific plants/animals.specific plants/animals.

Ecosystem Concepts and ComponentsEcosystem Concepts and Components

Biomes Biomes

Role of climate

Role of climate

Aquatic life zones

Aquatic life zones

Biomes - terrestrial ecosystemsBiomes - terrestrial ecosystemsBiomes - terrestrial ecosystemsBiomes - terrestrial ecosystems

Dry woodlands and shrublands (chaparral)

Temperate grassland

Temperate deciduous forest

Boreal forest (taiga), evergreen coniferousforest (e.g., montane coniferous forest)

Arctic tundra (polar grasslands)

Tropical savanna,thorn forest

Tropical scrub forest

Tropical deciduous forest

Tropical rain forest,tropical evergreen forest

Desert

Ice

Mountains(complex zonation)

Semidesert,arid grassland

Tropic ofCapricorn

Equator

Tropic ofCancer

BiomesBiomesBiomesBiomes

• Determined primarily by Determined primarily by precipitationprecipitation

– ForestsForests (> 75 cm rain per year) (> 75 cm rain per year)

– GrasslandsGrasslands (30-75 cm rain per year) (30-75 cm rain per year)

– DesertsDeserts (< 30 cm rain per year) (< 30 cm rain per year)

BiomesBiomesBiomesBiomes

• Determined secondarily by Determined secondarily by temperaturetemperature– Type of forest, grassland, or desert Type of forest, grassland, or desert

determined by average annual determined by average annual temperaturetemperature

Aquatic ecosystemsAquatic ecosystemsAquatic ecosystemsAquatic ecosystems

• Determined by salinityDetermined by salinity– MarineMarine

– EstuaryEstuary

– FreshwaterFreshwater

Type determined by: depth, nearness Type determined by: depth, nearness to shore, size, water movementto shore, size, water movement

Ecosystem FunctionEcosystem Function

One-way flowof energy

One-way flowof energy

Cycling ofmatter

Cycling ofmatter

Matter and Energy Flow in EcosystemsMatter and Energy Flow in Ecosystems

Food chainsFood chains Food websFood webs

TrophicTrophiclevelslevels

Producer to primaryconsumer

Primaryto secondaryconsumer

Secondary tohigher-levelconsumer

All producers andconsumers todecomposers

Fungi

Gambel'squail

Red-tailed hawk

Collaredlizard

Jackrabbit

Yucca

Kangaroo ratKangaroo rat

AgaveAgave

RoadrunnerRoadrunner

Diamondback rattlesnakeDiamondback rattlesnakeDarklingbeetleDarklingbeetle

BacteriaBacteria

Pricklypearcactus

Pricklypearcactus

Ecological PyramidsEcological Pyramids

Pyramid ofenergy flow

Pyramid ofenergy flow

Ecologicalefficiency (10%)

Ecologicalefficiency (10%)

Pyramid ofbiomass

Pyramid ofbiomass

Pyramid ofnumbers

Pyramid ofnumbers

Energy Productivity of EcosystemsEnergy Productivity of Ecosystems

Primary productivityPrimary productivity

Secondary productivitySecondary productivity

Energy stored/area/timeEnergy stored/area/time

Matter Cycling in EcosystemsMatter Cycling in Ecosystems

-Biogeochemical or nutrient cycles-Biogeochemical or nutrient cycles

-Hydrologic cycle (H2O)-Hydrologic cycle (H2O)

-Atmospheric or gaseous cycles (C, N)-Atmospheric or gaseous cycles (C, N)

-Sedimentary cycles (P, S)-Sedimentary cycles (P, S)

Hydrologic (Water) CycleHydrologic (Water) Cycle

Driven by physical forcesDriven by physical forces

The Carbon CycleThe Carbon Cycle

Driven by biological forces:Driven by biological forces:photosynthesis and respirationphotosynthesis and respiration

The Nitrogen CycleThe Nitrogen Cycle

Driven by biological forces: bacteriaDriven by biological forces: bacteria

Root nodulesRoot noduleson legumeson legumes

CyanobacteriaCyanobacteria

The Phosphorus CycleThe Phosphorus Cycle

Driven by physical forcesDriven by physical forces

Community ChangeCommunity Change

Ecological succession - gradualreplacement of one kind of communityof organisms by another over time

Ecological succession - gradualreplacement of one kind of communityof organisms by another over time

-Initiated by disturbance-Initiated by disturbance

Ecological Succession: Communities in Transition - Type #1Ecological Succession: Communities in Transition - Type #1

Primary successionPrimary succession

- begins with barren area, no soil- begins with barren area, no soil

Ecological Succession: Communities in Transition - Type #1Ecological Succession: Communities in Transition - Type #1

Slow soil development by weathering,activities of tolerant species

Slow soil development by weathering,activities of tolerant species- pioneer species- pioneer species

Ecological Succession: Communities in Transition - Type #1Ecological Succession: Communities in Transition - Type #1

Gradual changeover to less tolerantspecies over long periods of time

Gradual changeover to less tolerantspecies over long periods of time

- equilibrium or successional species- equilibrium or successional species

Primary SuccessionPrimary Succession

Ecological Succession: Communities in Transition - Type #2Ecological Succession: Communities in Transition - Type #2

Secondary successionSecondary succession

- begins with soil already in place- begins with soil already in place

Ecological Succession: Communities in Transition - Type #2Ecological Succession: Communities in Transition - Type #2

Rapid changeover to less tolerantspecies over shorter periods of time

Rapid changeover to less tolerantspecies over shorter periods of time- rapid because soil already present- rapid because soil already present

Secondary SuccessionSecondary Succession

Succession and WildlifeSuccession and Wildlife

The End ProductThe End Product

If undisturbed, communities changetoward a relatively stable stage

If undisturbed, communities changetoward a relatively stable stage

- climax community- climax community

- long-term presence if not disturbed- dominated by less-tolerant species- general equilibrium

- long-term presence if not disturbed- dominated by less-tolerant species- general equilibrium