ECOLOGY

Chapter 3

WHAT IS ECOLOGY?

Section 3-1

ECOLOGY Ecology is the study of organisms and their

interaction with the environment.

An organism is any living thing Examples: Humans, animals, plant, bacteria

ECOLOGY The Biosphere

The biosphere is the combined portions of the planet where life exists, including land, air, water, or atmosphere.

It extends from about 8 kilometers above the earth’s atmosphere to about 11 kilometers below the surface of the water

LEVELS OF ORGANIZATION To understand the

relationships within the biosphere, ecologists ask questions about events and organisms that range in complexity from a single individual to the entire population

INDIVIDUAL POPULATION COMMUNITY ECOSYSTEM BIOME BIOSPHERE

IMPORTANT VOCABULERY -Species (individual) group of similar organisms can

breed and produce fertile offspring  -Populations- group of individuals of same species that

live in the same area  -Communities- group of populations that live together

in a defined area  -Ecosystem- collection of all organisms in a particular

place includes nonliving or physical environment  -Biome- group of ecosystems that have the same

climate and similar dominate communities

-Biosphere- all portions of living planet

TH

INK

OF A

MN

MO

MIC

TO

REM

EM

BER

TH

E L

EV

ELS

BBECPS

WH

AT’A

YO

UR

MN

MO

NIC

?

BBECPS

Bad Boys Escapes Community Prison Suddenly

BIOLOGICAL METHODSRegardless of the tools they use, scientists conduct modern ecological research using three basic approaches

1. Observing -What species live

here? -How many species?

2. Experimenting -test hypotheses -set up experiment

in lab or field 3. Modeling

-make models -predictions -test further with

observations and experiments

ENERGY FLOW

Section 3-2

PRODUCERS

The sun is the main source of energy for life on earth

HOWEVER, there are some organisms that rely on other sources of energy These organisms use energy

stored in inorganic (bonds that do not contain carbon) chemical compoundsA good example of these types of organisms are those found deep in the ocean near thermal ventsThe organisms use the chemical energy that is loaded in the water surrounding the vent

AUTOTROPHS A groups of organisms that can use the

energy in sunlight to convert water and carbon dioxide into Glucose (food)

Autotrophs are also called Producers because they produce all of the food that heterotrophs use

Without autotrophs, there would be no life on this planet

Ex. Plants, Algae, and certain Bacteria

AUTOTROPHS

BREAK DOWN THE WORD

Auto - SELF

Troph - FOOD

AUTOTROPHS Chemotrophs

Autotrophs that get their energy from inorganic substances, such as salt

Live deep down in the ocean where there is no sunlight

Ex. Bacteria and Deep Sea Worms

HOW DO THEY MAKE THEIR OWN FOOD?

PHOTO – light SYNTHESIS – to make Harness solar energy

to produce food Where?

On land ---plants main autotrophs

In water --- upper layers of water

CHEMO – chemical SYNTHESIS – to make Harness chemical

energy to produce food with the absence of light

Where? On land – mainly

bacteria in hot springs In water – deep ocean

floor volcanic vents

PHOTOSYNTHESIS CHEMOSYNTHESIS

CONSUMERS Many organisms cannot make their

own food. The ONLY way to obtain energy is from other organisms…….these organisms are called consumers or heterotrophs

Definition- organisms that rely on other organisms for their energy and food supplyHETERO – otherTROPH - food

HETEROTROPHS

THERE ARE DIFFERENT SUB-TYPES OF CONSUMERS

HerbivoresOmnivoresCarnivoresDetritivoresDecomposers

DIFFERENT SUB-TYPES OF CONSUMERS

Consumers/heterotrophs1. Scavengers/Detritivores – feed on the

tissue of dead organisms (both plans and animals) DETRITIUS- dead matter VORES – to consume Ex. – Vultures, Crows, and Shrimp

SUB-TYPES OF CONSUMERS Consumers/heterotrophs

2. Herbivores – eat ONLY plants HERBI – a plant VORE – to consume Ex. – Cows, Elephants, Giraffes

SUB-TYPES OF CONSUMERS Consumers/heterotrophs

3. Carnivores – eat ONLY meat CARNI – MEAT VORE – to consume Ex. – Lions, Tigers, Sharks

SUB-TYPES OF CONSUMERS Consumers/heterotrophs

4. Omnivores – eat BOTH plants and animals OMNI – all vore- to consume Ex. – Bears and Humans

FEEDING RELATIONSHIPSEnergy flows through an ecosystem in one direction from the sun to producers then to consumers

TRANSFER OF ENERGY When a zebra eats the grass, it does

not obtain all of the energy the grass has (much of it is not eaten)

When a lion eats a zebra, it does not get all of the energy from the zebra (much of it is lost as heat)

TRANSFER OF ENERGY The two (2) previous examples of

energy transfer show that no organism EVER receives all of the energy from the organism they just ate

Only 10% of the energy from one trophic level is transferred to the next – this is called the 10% law

TROPHIC LEVELS Energy moves from one organisms to

another when it is eaten

Each step in this transfer of energy is know as a trophic levelThe main trophic levels are producers,

consumers, and decomposers

FOOD CHAINS The energy flow from one trophic level to the

other is know as a food chain A food chain is simple and direct It involves one organism at each trophic level

Primary Consumers – eat autotrophs (producers)Secondary Consumers – eat the primary consumersTertiary Consumers – eat the secondary consumersDecomposers – bacteria and fungi that break down

dead organisms and recycle the material back into the environment

FOOD CHAIN

FOOD WEB Most organisms eat more the JUST one

organism

When more organism are involved it is know as a FOOD WEB

Food webs are more complex and involve lots of organisms

FO

OD

W

EB

FOOD WEB

ECOLOGICAL PYRAMIDSDiagram that shows the relative amount of energy or matter contained within each trophic level in a food chain or food web

ECOLOGICAL PYRAMID An ecological

pyramid shows the relationship between consumers and producers at different trophic levels in an ecosystem

(see diagram to right)

The Pyramid shows which level has the most energy and the highest number of organisms

Three Main Types of Ecological Pyramids

ENERGY BIOMASS NUMBERS

ENERGY PYRAMIDOnly about 10% of the energy available within one trophic level is transferred to organisms at the next trophic level

Ecological Pyramid of Energy

ECOLOGICAL PYRAMID of ENERGY

Pyramid of BIOMASS The total mass of the organic matter

(living matter) at each trophic level is called biomass

Biomass is usually expressed in grams per unit area

Biomass is just another term for potential energy – energy that is to be eaten and used.

BIOMASS PYRAMID

Pyramid of Numbers

Pyramid of Numbers

ECOLOGICAL PYRAMID

• Which level has the most energy?• Which level has the most organisms?• Which level has the least organisms?• Which level has the least energy?

CYCLES OF MATTER

Section 3-3

CYCLES OF ENERGYUnlike the one way flow of energy,

matter is recycled within and in between ecosystems

WATER CYCLE

Organisms need water for metabolism (all chemical reactions) Water is necessary for photosynthesis

Plants absorb water into their roots Animals drink water or consume it in

their food

Evaporation – water changes into gasTranspiration – water evaporation from

leaves

STEPS OF THE WATER CYCLE

1. Water evaporates from lakes, rivers, oceans, etc..

2. Plants give off water in a process called transpiration

3. Water condenses in the atmosphere and falls back to earth in the form of precipitation

4. The water runs off back into lakes, rivers, etc.

5. The cycle repeats

STEPS OF THE WATER CYCLE

Ways to return water to the environment 1. respiration 2. excretion (animal wastes) 3.transpiration (plants) 4. precipitation

CARBON CYCLE Carbon is found in the environment as

carbon dioxide Carbon dioxide is needed for photosynthesis Carbon dioxide is returned to the

environment in 3 ways 1. respiration 2. decomposition 3. the burning of fossil fuels.

NITROGEN CYCLE

The atmosphere is 78% nitrogen, 21% oxygen, 1% other gases

We can't use nitrogen in the air we breath - it must come from the foods we eat.

NITROGEN CYCLE Nitrogen compounds are important for 3

major reasons in humans: 1. Proteins- are necessary for muscle

development and certain chemical reactions (blood clotting)

2. Enzymes and hormones - control chemical reactions in your body - digestion, reproduction etc.

3. Nucleic Acids - carry the traits from one generation to the next

NITROGEN CYCLE

Nitrogen compounds are placed back in food chains 2 major ways: 1. Decomposers

2. Nitrogen-fixing bacteria- bacteria on the roots of certain plants (legumes - peas, beans) take nitrogen from the air and put it in the soil

PHOSPHORUS CYCLE

essential to living organisms because it forms part of life sustaining molecules, such as DNA and RNA

Where is P found?not very common in biospheremostly land, rocks, soilas rocks wear down, p is releasedused by marine animals

NUTRIENT CYCLES Primary productivity- rate which organic

matter is created by producers What is the factor that controls primary

productivity? limiting nutrient when ecosystem is limited by

single nutrient that is scare or cycles very slowly

Farmers aware of this and use fertilizers with nitrogen, phosphate and potassium

run-off causes nutrient poor oceans to get lots of nutrient

algal bloom- disrupts ecosystem

THE END