Ecology: The Study of Ecosystems

Mrs. Hart

Biology

What is an Ecosystem?

An ecosystem includes all the living and non-living things in a given area

Biotic Factors: Living ThingsEx:Abiotic Factors: Non-Living ThingsEx:

How does the ecosystem get energy?

Autotrophs

Living things that can make their own foodGreen Plants that have “chlorophyll” are

able to convert the sun’s energy to chemical energy (food)

This process is called photosynthesisAutotrophs are also known as “Producers”

because they produce the energy for the ecosystem

How do the rest of us get energy?

We’ve got to EAT!!!

Heterotrophs: Living things that are NOT able to make their own energy; we must eat other living things for energy

Heterotrophs are also known as “Consumers” because they consume other living things for energy

But what kind of living things do we eat???

Herbivores

Eat only plants!!!

Carnivores

Eat only meat

Omnivores

Eat both plant and animal material

Is there another type of feeder?

Decomposers: Live off of dead living things and wastes

Scavengers

Consumers that eat animals that are already dead

How can we organize the different types of feeders?

Food chain- A diagram of what eats whatTrophic Levels- A name for the feeding

levels within a food chainProducers, Primary Consumers,

Secondary Consumers, Tertiary Consumers, Decomposers

Food Webs

Many interconnected food chains within an ecosystem

Can be very complicated

Quick Quiz:

1. What only eats plants?

2. Who always starts the food chain?

3. Who eats plants AND animals?

4. Who only eats animals?

5. How is a Food Web different from a Food Chain?

Quick Quiz, cont.6. Who eats EVERYBODY when they’re

dead? 7. What do we call producers (like plants)

who make their own food?8. What is the other name for consumers? 9. What is the name for living things in the

environment?10. What is the name for non-living things in

the environment?

Matter is recycled

How is matter recycled?It moves from the producers, to the

consumers, through the food webThen it is broken down by decomposersThen it is taken up as nutrients by producersWhat is recycled?Carbon, Nitrogen, Phosphorus, SulfurMany more!!!!!!!

What about energy???

Energy moves through the food chain, from producers to consumers to decomposers

Where does the energy come from??? Is energy recycled?What is the “Law of Conservation of

Energy” aka “The First Law of Thermodynamics”……

Energy Cannot be Created or

Destroyed!!!

However, Energy is NOT recycled…

Answer: it is changed from one form to another.

Where does the energy go?

Most of the energy at each trophic level is used by the living things to conduct their metabolism, in hunting/killing/consuming food, and in other life activities

Not all living material is consumed, ex: bones, bark, etc. These parts will be decomposed

So where does this energy go?

The Law of 10%

At each trophic level, 90% of the available energy is used, with most of it being “lost” as heat to the atmosphere.

Only 10% of the energy at each level is available to the next trophic level

So if a producer has 10,000 Calories (or kilocalories) of energy, how much energy would each level after that have?

Energy Pyramid

Energy Can also be measured in Joules (J)

What does this mean for higher level consumers?

There’s less energy

That means there are lower numbers of higher level consumers, and higher levels of producers and lower level consumers

What will happen to an ecosystem if all of the producers are killed? (Think deforestation, forest fire, drought, etc)

Symbiosis

Living together

-Two different species

Parasitism

Not symbiotic Causes harm to host

A tapeworm in a

person or animal

intestines

Mutualism

Both organisms derive mutual benefit

tickbirds and rhinos

Commensalism

Only one member benefits The other member: no benefit/ no harm

Whale and barnacles

Barnacle: gets place to live/feed.

Whale: no harm/no benefit