how can changes in an environment affect the

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How can changes in an environment affect the

organisms that live there?

What causes an ecosystem to change?

It may be hard to notice, but ecosystems are always changing, some changes make it hard for living things to survive.

These changes can happen by: 1) Natural events. 2) Animals. 3) People.

Natural events that causes changes in ecosystem:

1 -Volcanoes:

-Volcanoes can fill a valley with ash.

2 -Hurricanes:

- Hurricanes can destroy coastal wetlands.

3 -A lot of rain:

- A lot of rain can cause landslides, turning hills to rivers of mud.

4 -Too little rain:

- Too little rain causes drought "soil dry up".

Animals that cause changes in ecosystems

A swarm of Locusts can eat any plants along their path leaving a whole community without food

An alligator makes holes in muddy wetlands by its feet, tail & snout.

when these holes are filled with water, it helps animals to survive in droughts.

People that cause changes in ecosystems

1 )Deforestation

- When people cut down the forests to build houses & buildings, This destroy many forest habitats.- Living things lose their homes & source of food

2 )Overpopulatio

n- When too many individuals live in an area.-The more people there are, the more they use & consume.- So water & space become harder to find.

3 )Pollution

- It’s adding harmful things to air & water.-Cars, trunks & power plants give off gases which can harm the air we breathe.-Litter “ Trash that is disposed in properly” is a form of pollution too.- Pollution can kill plants & animals in an ecosystem

4 )Protection-People driving less & using hybrid cars can protect the ecosystem.- People treat wastes to remove harmful substance.- Planting new trees, recycling paper, glass & plastic are ways of protecting your ecosystem.

What happens when an ecosystem change?

1 )Accommodati

ng- It’s how individuals respond to change.

Examples:

A fire can destroy the main food supply of an animal in a forest, so some animals like: deer can change their diet. They may eat tree bark instead of leaves.

-Others will use new plants or materials as shelter

2 )Moving Away:

When some animals cannot accommodate ecosystems change.-They find new places to live; their search for food, water & shelter may take them far away.

3 )Extinction:

Some living things cannot accommodate an ecosystem change or move away to another habitat.If an organism doesn't meet its needs, it will die.-Some times an entire species can slowly disappear.- A species is extinct when the last of its kind dies.ExampleDinosaurs – Passenger pigeon

Saving Panda bears

A living thing that has few of its kind is endangered. E.g. "Giant panda“

Large numbers of giant panda bears once lived in China.

Pandas eat bamboo.  When people began to cut down

the bamboo forests, the pandas could not find enough to eat, so they are endangered.

Scientists are trying to prevent the extinction of panda bears.

Large areas of land in China are preserved for pandas to live.

Now, panda cubs are born in these protected places.

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