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

PLANTS ACTIVITIES

PLANT REPRODUCTION: FRUITS AND SEEDS

After the pollen grains reach the stigma, a fruit forms.
Inside the fruit are the seeds.
Fruits can be fleshy or dry.

• Fleshy fruits contain a lot of water. They are juicy.
• Dry fruits contain little water.

Inside each seed there is a tiny plant.
The seed falls to the ground, absorbs water, then germinates.
The little plant starts to grow and becomes a new plant.

Fleshy fruits, from ndhealthfacts

Dry fruits, from americandryfruit

PLANT REPRODUCTION: POLLINATION

Pollination is the transfer of pollen from the stamens of one flower to the stigma of the same or of another flower.
Some plants have very beautiful flowers.
They attract insects which land on the flowers.
Pollen sticks to the insects.
The insects carry the pollen to other flowers.
Other plants are not so attractive to insects.
They produce a lot of pollen grains, which the wind carries to the stigmas of other flowers.

Bee collecting pollen. Photo by Jon Sullivan, in PDPhoto.org

PLANT REPRODUCTION: FLOWERS

The plant's reproductive organs are in the flowers.
Flowers have four main parts:

• Tha calyx. This is made up of small green leaves called sepals. Sepals protect the flower.
• The corolla. This is made up of coloured leaves called petals.
• The stamens. These are the male parts of the flower. They produce pollen.
• The pistil. This is the female part of the flower. It is shaped like a bottle. It consists of the stigma, the style and the ovary.

PLANT NUTRITION: PHOTOSYNTHESIS

Plant make their own food in their leaves.
This process is called photosynthesis.
Water and mineral salts travel from the roots through the stem to the leaves.
In the leaves, the water and mineral salts mix with carbon dioxide and become food for the plant.
To carry out photosynthesis, plants need to use a lot of energy from sunlight.
During photosynthesis, plants release oxygen.
All the oxygen in the air comes from photosynthesis.

Photo from mdkshareef111

PLANT NUTRITION: CARBON DIOXIDE

Carbon dioxide is one of the gases found in air.
Living things release carbon dioxide when they breathe.
Carbon dioxide is always released when something burns.
It is also released by car engines.
Plants take in carbon dioxide through their leaves.

Photo from blogspan.

Photo from Ecofriend.

Photo from Gizmag (Shutterstock)

Photo from Real Trees 4 Kids

OUR PLANTS

Here you have some photos of the plants we have at home:

To start here you have the plant that Alex shared with us:

And here there are the plants that Claudia wants to show you:

Lydia wants us to see this plant:

Susana has to show you a video of her plant, it is a very special one:

This is the plant that Juan brought to our class this morning:

And this is the plant that Andrea shared with us:

Here you have Paula's cactus:

All of them are wonderful, please, show us your plants!

PLANT NUTRITION: WATER AND MINERAL SALTS

All plants need watering.
If you do not water a plant, first it withers, then it dies.


Plants take in water through very fine root hairs on their roots.

Photo from doctortee, by John Tiftickjian

Plants also need to take in mineral salts from the soil.
Mineral salts dissolve in water, so plants take them in through their roots with the water.
Farmers add fertilisers to the soil because fertilisers contain mineral salts.

PLANT NUTRITION: HOW PLANTS MAKE FOOD

Plants make their own food.
To make their food, plants need:

• Sunlight.
• Mineral salts from the soil.
• Carbon dioxide from the air.
• Water.

Photo from nelsonthornes.com

PARTS OF PLANTS: LEAVES

The leaves of a plant are the green parts that grow from the stem.
They have two parts:

• The petiole is the part connected to the stem.
• The blade is the widest part of the leaf. It can have many different shapes.

The plants which lose their leaves in autumn are called decidious.

The plants which have green leaves all year round are called evergreens.

Evergreen Tree. Photo from Sevacall

Decidious Tree.
Photo by Gregor Richardson in Otago Daily Times