Ecology Review

Ecosystems

The environment and the organisms that live The environment and the organisms that live in itin it

Food chains/food webs show how the energy Food chains/food webs show how the energy moves through an ecosystemmoves through an ecosystem

Food chains look at one direct line Food chains look at one direct line

Food web looks at all of the energy Food web looks at all of the energy transferring in a whole ecosystemtransferring in a whole ecosystem

Ogranisms….

In an ecosystem can be producers, In an ecosystem can be producers, consumers, or decomposersconsumers, or decomposers

Producers make their own foodProducers make their own food

Consumers do not; they eat both producers Consumers do not; they eat both producers and consumersand consumers

Decomposers break down waste and decayed Decomposers break down waste and decayed material from both producers and consumersmaterial from both producers and consumers

Producers….

Produce their own foodProduce their own food

Producers are plantsProducers are plants

Producers are eaten by consumersProducers are eaten by consumers

Producers are the first organisms in the food Producers are the first organisms in the food chains (after the energy source)chains (after the energy source)

Consumers…

Can be herbivores ---- eat only plants Can be herbivores ---- eat only plants (remember herbs are plants)(remember herbs are plants)

Can be carnivores ---- eat only meatCan be carnivores ---- eat only meat

Can be omivores – eat both plants and meatCan be omivores – eat both plants and meat

Decomposers…..

Break down waster material and decaying Break down waster material and decaying organisms (organisms that have died)organisms (organisms that have died)

Food chains….

Start with an energy source (usually the sun)Start with an energy source (usually the sun)

Then there is a producersThen there is a producers

Producer is eaten by a consumerProducer is eaten by a consumer

This is a PRIMARY CONSUMERThis is a PRIMARY CONSUMER

The primary consumer is eaten by another consumerThe primary consumer is eaten by another consumer

This consumer is a higher order/level consumer – the 2This consumer is a higher order/level consumer – the 2ndnd one is a secondary consumerone is a secondary consumer

And so on ….And so on ….

Food Chain Example

First picture – sun ---- energy source & sunflowers ----producersSecond picture – bird – primary consumer ---- bird eat the seeds from sunflowersThird picture – wolf – secondary consumer – wolves eat birds

Food webs

Show all of the food chains in an ecosystemShow all of the food chains in an ecosystem

Show how the energy is transferredShow how the energy is transferred

Food web example

Disturbances

Disturbances in the environment can affect Disturbances in the environment can affect the overall food webthe overall food web

Go back to the food web….Go back to the food web….

Take a look at the chain inside the food web of Take a look at the chain inside the food web of the grass and the antthe grass and the ant

What organisms feed off the ant?What organisms feed off the ant?

Disturbances…..

Mice and spiders feed off the antsMice and spiders feed off the ants

What do you think would happen if the ant What do you think would happen if the ant population was disturbed?population was disturbed?

The population can be disturbed by pesticides or The population can be disturbed by pesticides or other random events in the environmentother random events in the environment

Disturbances

So if the ant population went downSo if the ant population went down

Then the mice and the spiders would have Then the mice and the spiders would have less to feed own which could cause them to less to feed own which could cause them to starve and diestarve and die

And the grass would not have something And the grass would not have something eating it as much so it would grow more and eating it as much so it would grow more and maybe out of controlmaybe out of control