Ecology

What is Ecology?

• https://www.youtube.com/watch?v=TGR-QGdH3QU

Ecology• The study of the interactions of different organisms

(living things) between each other and with their environment (surroundings).

• The Greek word “logos” means “to study.”• “Eco” comes from the Greek word “oikos” which

means “house”.

• An organism can interact between both biotic factors (living things) and abiotic factors (non-living things).

Biotic Factors Abiotic Factors

• “Bio” is the Greek word meaning “life.”

• There are six levels of organization in ecology:

Multiple populations

Community in its environment

A group of

ecosystems that have

a similar climate and

organisms

The part of the

Earth that supports

life (the air, earth &

water)

More than one of that individual

One animal or plant

Individual?

Population?

Community?

Ecosystem?

Biome?

Biosphere?

Biomes

• Regions of the world with similar climate(weather, temperature) plants and animals.

• Biomes can be either terrestrial (on land) or aquatic (in water).

Biomes

What biome did you come from?

Biomes

AQUATIC BIOMES TERRESTRIAL BIOMES

Freshwater Tundra

Freshwater Wetlands Rainforest

Marine Grassland (savannah)

Coral Reef Taiga

Estuaries Deciduous Forest

Desert

Alpine

Chaparral

Why study ecology?

• Understanding the interconnections between living things and their environment can help us to make more sustainable choices.

• Sustainability means meeting the needs of the present without affecting the ability of future generations to meet their needs.

Why should we care?

• What are some things that all organisms need to survive? air, water, food, shelter

• All of these come from our environment. If our environment is not healthy, we may not be able to survive.

• How much of the Earth is made up of land? • about ¼

• How much of the Earth’s surface has the potential to grow food?

• 1/32

• What are some things we can do to help the environment?

Calculate your Ecological Footprint• Ecological Footprint: The ecological footprint measures

human demand on nature, i.e., the quantity of nature it takes to support people (how much “nature” can we actually use?)

• It is the amount of the environment needed to produce the stuff necessary to support a particular lifestyle.

• It helps us to determine the impact that our use of energy, food and water has on the environment.

• Knowing our footprint can help us start to think of ways to make more sustainable choices to leave a smaller footprint.

Food Chains, Food Webs and Energy Transfer in Ecosystems

• Every living organism has a place where it normally lives and grows. This is called its natural habitat.

• The unique job an organism does in its environment is called its niche.

• An organism’s job may be to produce, consume, or decompose. They do this to get the food (for energy) that they need to live.

Example: Can you guess some of the roles of a rabbit in its natural environment?

Watch the video and listen for the niche of a rabbit.

• Since plants produce their own food from the sun, they are PRODUCERS.

• Animals cannot produce their own food. They must eat plants or other animals for energy. Therefore, they are CONSUMERS.

Types of Consumers

Consumer What They Eat Example Picture

Only plants

Plants andanimals

Only animals

Herbivore

Omnivore

Carnivore

Scavengers• Scavengers are

consumers that eat the bodies of larger, deadanimals.

• Ex: Vultures, bald eagles, ravens, hyenasand some ants.

Decomposers (and Detritivores)• Decomposers (and detritivores) decompose,

or break apart, smaller dead animals, dead plants, and animal waste to get energy.

• This process turns the waste into the nutrientsin the soil that plants need to grow.

• Examples: Bacteria, fungi, crabs, earthworms, wood beetles, dung beetles.

• https://www.youtube.com/watch?v=bJEToQ49Yjc

Food Chains• Food chains tell us what eats what. They show

the movement of energy in an ecosystem.

• Not all energy moves on because it is used by the organisms for life processes: growth, reproduction, movement, etc.

• Herbivores and omnivores are examples of primaryconsumers; Omnivores and carnivores are secondary, tertiary and top level consumers. Decomposers are found at all levels since plants and animals can die at any point.

Where Does Energy Come From?

Photosynthesis

• Sunlight energy is used by plants to make their own food. This process is called photosynthesis.

Photosynthesis Equation

How do living things use oxygen and sugar to produce energy? In the reverse process called respiration.

• The pyramid of energy shows us why food chains only have four or five steps. It’s because there’s not enough energy for more! This is why there are very few topcarnivores.

Pyramid of Energy

Pyramid of Biomass• The pyramid of biomass shows the total mass of

organisms at each stage of a food chain.

• These can support an even fewer number of secondary or tertiary consumers.

• It again shows the importance of soil.

• It takes a large number of producers to support a small number of primary consumers.

Food Webs• Food webs show all possible paths for energy to flow

in an ecosystem.

• They are made up of lots of food chains.

Let’s trace some of the food chains within this food web.

Food Web Activity

• http://forces.si.edu/ltop/pdfs/2-5-WeavingTheWeb.pdf

• You try! Write down 3 food chains within this aquatic food web.

Components of a Food Chain

• Tertiary Consumer

• Primary Consumer

• Secondary Consumer

• Producer

• Herbivore

• Carnivore

• Omnivore

Add the following terms to the food chains you created:

Where do the arrows go? ()

What is missing from these food chains?

Review for Quiz• Work on Worksheets• Know the meaning of these words:

– Producer - Herbivore - Habitat– Consumer - Carnivore - Ecosystem– Scavenger - Omnivore - Ecology– Decomposer - Niche - biome– Primary Consumer - Secondary Consumer– Tertiary Consumer - Top Consumer

• Explain what happens to the energy as it moves through the food chain

• Write the equation for photosynthesis in words

Species Interactions• Our web activity helped us to see that no organism

exists in isolation. Individual organisms live together in an ecosystem and depend on one another.

• In fact, they have many different types of interactions with each other, and many of these interactions are critical for their survival.

Population Dynamics

• Recall: Population means all the organisms of the same species that live in a certain area.

• Population growth depends on several things. The four factors affecting population size are:

(natality) (mortality)

• What factors are involved in the reproduction and death of a species? (What kind of things can change the population?)

– Food supply

– Disease

– Birth control

– Climate

– Job availability

– War/predation

– Availability of space

– Natural disasters

* These are called limitingfactors. They can be characterized in two categories.

1. Density Dependent

– Factors that can change the population because of the amount of organisms that live in that population.

Limiting Factors can be characterized in

two categories:

2. Density Independent

– Factors that can change the population regardless of the amount of organisms that live in that population.

Human

activity

Competition -/-

• Competition within an ecosystem occurs when organisms seek the same limited resource for survival and population growth (such as food, water or shelter).

• If the niches for two different species contain the same fooditem or the same living space, then members of those species will be in conflict with one another for those parts of their niches.

• The greater the population, the greater the competition.

Competition can occur:

• against one’s own species (intraspecific)

• And between different species (interspecific).

Natural Occurrences

Human Activity

Predation +/-• This is when one organism kills and eats

another organism.

• Predator (hunter) – hunts and kills other animals for food

• Prey (the hunted) – animals the predator hunts

Parasites **Not in notes

Parasitism +/-

• One organism benefits, the other is harmed– Some live within the host

• Tapeworms

• Heartworms

• Bacteria

– Some feed on the external surface of the host• Ticks

• Fleas

• Mistletoe

– Most do not kill their host (at least not quickly)

Fly worksheet

Population Curves

• These show changes, growth, decline and limits of a population. They are useful to determine how healthy a population is in an ecosystem.

• Is it possible to have infinite population growth?

0

20000000

40000000

60000000

80000000

100000000

120000000

140000000

160000000

180000000

200000000

1 2 3 4 5 6

Houseflies Pop. Growth

1

2

3

4

• 1 – slow growth: only a few able to reproduce; the population adjusts to environmental conditions

• 2 – rapid growth: many are able to reproduce; the steepness depends on limiting factors

• 3 – zero growth: the population growth is stable and at its maximum. The population has reached its carrying capacity

• 4 – decline: the population decreases from lack of resources, predation, human activity, etc.

1

2

3

4

*Carrying capacity – the largest population of a species that a particular ecosystem can support

Sustainability

• Can the Earth support this population increase?

Thoughts?

Predator-Prey Graph

Whose atoms are you made of?

Biotic elements

Abiotic elements

…Matter - Matter is never lost or gained; It is used over

and over again in different forms.

…Energy - Energy cannot be created or destroyed; It is

changed from one form into another.

Remember: Law of

Conservation of….

• https://www.educationsoutheastwater.com.au/resources/natural-water-cycle-interactive#evaporation

The Water Cycle

transpiration

Biogeochemical Cycles

• This means that the same nutrients have been recycled over and over again through organisms and the environment since the beginning of the Earth!

• This means all living things are deeply interconnectedwith each other and their environment!

• These cycles are called biogeochemical cycles.

(bio = living, geo = Earth)

• Nutrients that are used by organisms in large quantities are hydrogen, oxygen, (water), carbon, nitrogen and phosphorous.

The Carbon Cycle – part 1

When

organisms

die, some of

the carbon

gets buried

in the earth

Carbon Cycle

• Producers use the sun’s energy to take carbon dioxide from the air and convert it to sugar(photosynthesis).

• Carbon moves through the food chain when consumers eat plants and animals.

• The carbon is released when plants and animals use the food to produce energy (respiration)

• When plants and animals die, decomposersbreak down their bodies and also produce carbon dioxide through respiration.

The Carbon Cycle – part 2

Combustion:

• Have humans interfered with this process?

• What is the effect?•T

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• Carbon cycle game:

• http://oceanservice.noaa.gov/education/pd/climate/teachingclimate/carbon_cycle_game.pdf

• Deforestation destroys plants that would normally have helped to remove carbon from the atmosphere

• Burning fossil fuels releases more carbon into the atmosphere.

• Carbon dioxide is a greenhouse gas. This means it absorbs and reemits heat energy.

• More CO2 in the atmosphere has caused the global temperature to change.

• Extra CO2 is also being

absorbed into the ocean.

Since CO2 is acidic,

scientists are researching

how this is affecting this

ecosystem.

Climate Change

• As you watch the video…

1. What are three effects of climate change?

2. Who is most responsible for climate change?

3. Who is most effected by climate change?

4. How can we stop climate change?

Video:

http://video.nationalgeographic.com/video/way-forward-climate