QOTD - NO MARK QUIZ 1. The number of deer in a forest is called… THE POPULATION THE POPULATION 2. Which does not belong? Sunshine, Water, Dirt or a rotting.

QOTD - NO MARK QUIZQOTD - NO MARK QUIZ1. The number of deer in a forest is called…1. The number of deer in a forest is called…

THE POPULATIONTHE POPULATION2. Which does not belong? Sunshine, Water, Dirt 2. Which does not belong? Sunshine, Water, Dirt

or a rotting log?or a rotting log? ROTTING LOG (Biotic)ROTTING LOG (Biotic)3. Name one ecologically significant region in 3. Name one ecologically significant region in

Can.Can.GREAT LAKES, PRAIRIES, CDN. SHIELD, ETC.GREAT LAKES, PRAIRIES, CDN. SHIELD, ETC.

4. The variety of living things is called…4. The variety of living things is called…BIODIVERSITYBIODIVERSITY

5. The process by which plants produce food is…5. The process by which plants produce food is…PHOTOSYNTHESISPHOTOSYNTHESIS

ECOSYSTEMS 101ECOSYSTEMS 101

DECIDUOUS FOREST

THE TUNDRA

BOREAL FOREST

GRASSLANDS

Energy in an EcosystemEnergy in an Ecosystem

• All living elements play a All living elements play a role in the functioning of an role in the functioning of an ecosystem.ecosystem.

• As energy flows through the As energy flows through the ecosystem, it is passed from ecosystem, it is passed from one organism to another.one organism to another.

• The energy coming into an The energy coming into an ecosystem originates from ecosystem originates from the Sun.the Sun.

PhotosynthesisPhotosynthesis

6CO6CO2 2 + 6H+ 6H22O + Light CO + Light C66HH1212OO66 + + 6O6O22 RAW

MATERIALS PRODUCTS

ProducersProducers

• Capture energy from the Capture energy from the sun and convert it to food sun and convert it to food energy (Photosynthesis).energy (Photosynthesis).

• Plants use this food energy Plants use this food energy and soil nutrients to live and and soil nutrients to live and reproduce.reproduce.

• When plants are eaten, When plants are eaten, some of this energy is some of this energy is passed along.passed along.

Types of ConsumersTypes of Consumers

• Consumers must Consumers must eat to obtain their eat to obtain their energy.energy.

• All animals are All animals are consumersconsumers

HERBIVORE

Types of ConsumersTypes of Consumers

CARNIVORE

OMNIVORE

Types of ConsumersTypes of Consumers

SCAVENGERS

DecomposersDecomposers

• After a consumer After a consumer dies, nutrients are dies, nutrients are returned to the soilreturned to the soil

• Decomposers recycle Decomposers recycle nutrients back to nutrients back to producers by producers by breaking down dead breaking down dead matter. matter.

• Moulds and Bacteria Moulds and Bacteria finish the job!finish the job!

Cellular RespirationCellular Respiration

CC66HH1212OO66 + 6O + 6O22 6H 6H22O + 6COO + 6CO22 RAW MATERIALS PRODUCTS

Sugar + oxygen = water + carbon dioxide

Photosynthesis and Photosynthesis and RespirationRespiration• Complementary processes – check it out…Complementary processes – check it out…

• Photosynthesis:Photosynthesis:

6CO6CO2 2 + 6H+ 6H22O + Light O + Light →→ C C66HH1212OO66 + 6O + 6O22

• Cellular Respiration:Cellular Respiration:

CC66HH1212OO66 + 6O + 6O22 →→ 6H 6H22O + 6COO + 6CO22

FOOD CHAINFOOD CHAIN•A connection of organisms showing the transfer of energy from one organism to the next.

Question…Question…

• WHAT’S WRONG WITH JUST USING WHAT’S WRONG WITH JUST USING FOOD CHAINS TO DESCRIBE THE FOOD CHAINS TO DESCRIBE THE RELATIONSHIPS WITHIN RELATIONSHIPS WITHIN ECOSYSTEMS?ECOSYSTEMS?

• FOOD WEBS are more realistic!FOOD WEBS are more realistic!

TROPHIC LEVELSTROPHIC LEVELS

• A way of categorizing living things A way of categorizing living things according to how they gain their according to how they gain their energy.energy.

• The 1The 1stst trophic level contains trophic level contains Autotrophs Autotrophs (organisms that make (organisms that make their own food)their own food)

• Each higher level contains Each higher level contains Heterotrophs Heterotrophs (eat others for energy)(eat others for energy)

TROPHIC LEVELS (Cont.)TROPHIC LEVELS (Cont.)

1st

2nd

3rd

4th

PRODUCERS (AUTOTROPHS)

Eg. GRASS

PRIMARY CONSUMERS

Eg. INSECTS

SECONDARY CONSUMERS

Eg. SPARROW

TERTIARY CONSUMERS

Eg. HAWK – TOP CARNIVORE

TROPHIC LEVELS (Cont.)TROPHIC LEVELS (Cont.)

TROPHIC LEVELS (Cont.)TROPHIC LEVELS (Cont.)

Energy Flow!Energy Flow!

• What is this What is this illustration illustration telling us?telling us?

--Trophic levelsTrophic levels

- Food web- Food web

- - Energy Energy Transfer?Transfer?

• Not all of the Sun’s energy is captured.Not all of the Sun’s energy is captured.

• As you go along up the trophic levels, As you go along up the trophic levels, energy is lost. energy is lost.

• [1 joule is the absolute [1 joule is the absolute minimum amount of energy minimum amount of energy required (on the surface of required (on the surface of Earth) to lift a one kilogram Earth) to lift a one kilogram object up by a height of 10 object up by a height of 10 centimeters.]centimeters.]

• So each level So each level loses about 90% loses about 90% of the energy in of the energy in the previous the previous level! And where level! And where does it go?does it go?

HEAT!HEAT!

Energy Pyramid

• The dry weight of all The dry weight of all organisms in all in an organisms in all in an ecosystem is known ecosystem is known as:as:

BIOMASS!BIOMASS!• So: As the amount of So: As the amount of

energy decreases ↓, energy decreases ↓, so does the so does the BIOMASSBIOMASS. .

• Therefore: there are Therefore: there are fewer animals at fewer animals at each trophic leveleach trophic level

Biomass Pyramid

Numbers PyramidNumbers Pyramid

• For example, in an forest ecosystem:For example, in an forest ecosystem:

- Grasses = 10,000,000,000 - Grasses = 10,000,000,000 organismsorganisms

- Grasshoppers = 27,000,000- Grasshoppers = 27,000,000

- Frogs = 90,000- Frogs = 90,000

- Trout = 300- Trout = 300

- Bear = 5- Bear = 5

BioaccumulationBioaccumulation • BioaccumulationBioaccumulation: :

How substances How substances (usually toxic) (usually toxic) build up in a build up in a biological systembiological system

• BiomagnificationBiomagnification

↑ ↑ increased increased concentration of a concentration of a toxin in the bodies toxin in the bodies of consumers at of consumers at each trophic level.each trophic level.

• MeHg = Methyl MercuryMeHg = Methyl Mercury

• Here is another look. This picture shows how Here is another look. This picture shows how weather through water works in spreading toxins.weather through water works in spreading toxins.

THE END!!!