ECOSYSTEMS ACTIVITIES AND TEST

PROTECTING ECOSYSTEMS

There are laws to protect ecosystems.
One way of protecting ecosystems is to make them nature reserves.
In this way the authorities look after them and prevent them from deteriorating.
There are many nature reserves throughout the world.

Lagoon in Peñalara, photo by Miguel303 in wikipedia

PROTECTING ECOSYSTEMS: OVEREXPLOITATION

Sometimes people take more animals or plants than the ecosystem can produce.
This is called overexploitation.
If we continue doing this, the animals or plants could become extinct.
One example is overfishing.
Sometimes people catch too many of one type of fish.
These fish are in danger of extinction.
This is happening to tuna fish and anchovies.

Overfishing

PROTECTING ECOSYSTEMS: DEFORESTATION

Deforestation is the disappearance of forests.
This happens when trees are cut down for wood or to make space for fields to grow crops.
Forests animals also disappear.
Erosion is another problem which destroys ecosystems.
This is when wind and rain sweep away the soil.
Plants and trees disappear.

 

PROTECTING ECOSYSTEMS: POLLUTION

Pollution can affect air, water and soil.

It can harm many living things in ecosystems.

Air pollution. Photo from wikipedia

Water pollution. Photo from wikipedia

Water pollution. Photo from ecofaxina

Soil pollution. Photo from wikipedia

PROTECTING ECOSYSTEMS: ECOSYSTEMS DETERIORATE

Living things in an ecosystem interact with each other.
An ecosystem deteriorates.
This can have serious effects on other living things.
Ecosystems deteriorate because of pollution, deforestation and overexploitation.

RELATIONSHIPS IN ECOSYSTEMS: COOPERATION

Living things also help each other.
We call this cooperation.
Some plants make nectar in their flowers.
Nectar is a sweet liquid which insects like very much.
As insects move from flower to flower to obtain nectar, they pollinate plants.
In this way, these plants and insects help each other.

RELATIONSHIPS IN ECOSYSTEMS: COMPETITION

Sometimes living things compete with each other to get what they need because they need the same things.
We call this competition.

• Plants compete for sunlight. Some plants grow very tall, very rapidly. Plants in the shade of other plants do not grow very much.
• Some birds compete for places to build their nests. Crows and falcons like the same rocky áreas to nest. Usually the falcons drive away the crows.

RELATIONSHIPS IN ECOSYSTEMS: FOOD CHAINS

To show how living things feed off other living things in an ecosystem, we can draw them in a row and link them with arrows.
This is called a food chain.
The rabbit eats the grass.
The rabbit is a primary consumer.
The genet eats the rabbit.
The genet is a secondary consumer.

GRASS. PRODUCER. From wikipedia.

RABBIT. PRIMARY CONSUMER. From wikipedia

GENET. SECONDARY CONSUMER. From wikipedia

 

RELATIONSHIPS IN ECOSYSTEMS: FOOD

In an ecosystem, each type of living thing needs different food.

• Plants produce their own food.
• Herbivores eat plants.
• Carnivores eat other animals.

Plants are called producers because they produce their own food.

Animals are called consumers because they eat, or consume, other living things.

Plants are essential, they produce the food which all living things need.

MAIN TYPES OF ECOSYSTEMS

There are many different types of ecosystems on Earth.
We can classify them into:
A.- Terrestrial ecosystems:

• Forests: forests have lots of trees. These provide food and shelter for animals.
• Grasslands: grasslands have lots of grass. Large herbivores eat the grass.
• Deserts: there are not many plants and animals in deserts because it does not rain very much.

B.- Aquatic ecosystems:

• Freshwater ecosystems: These are found in rivers, streams and lakes. Rivers and streams have moving water. Lakes have still water.
• Saltwater ecosystems: These ecosystems are in the sea. They are found on the coasts, in coral reefs and in the open sea.

Forest. Wikipedia

Grassland. Wikipedia

Desert. Wikipedia

Freshwater ecosystem. Wikipedia

Coral Reef. Saltwater ecosyste. Wikipedia

ECOSYSTEMS

An ecosystem is made up of all the living things and all the non-living components that function together in one place:

• Living things: these are the plants and animals living in the ecosystem.
• The environment: this is everything which affects these living things, such as temperature, water, the type of soil, types of rock...

LIVING THINGS HAVE DIFFERENT NEEDS

All plants need water and sunlight.
Some plants need a lot of water and usually grow near rivers.
Other plants do not need much water so they grow in deserts.
Animals need different things, too.
Fish need to live in water to breathe.
Most birds need to live in a place with trees so they can build their nests.
Living things live in places where they can satisfy their needs.
This is why you find different living things in different places.

Weeping willow, from Wikipedia

Cacti, from Wikipedia

Fish, picture by Peter Symonds on Wikipedia

Black Woodpecker nest in a tree, by Alastair Rae on Wikipedia

REMEMBER

LIVING THINGS AND NUTRITION
Plants make their own food.
To do this, they need water, mineral salts, carbon dioxide and sunlight.


POLLUTION
People, animals and plants need clean water and fresh air.
Sometimes water and air are polluted