Lesson video

Hi everyone, I'm miss Reid and welcome to a unit on all about geography on biomes.

Let's have a look at our lesson question.

So our lesson question for today is, what are the earth's biomes? Now in this lesson, we are going to be learning about the earth's six major biomes.

We will learn about their specific climates, and how these climates are impacted by their proximity or closeness to the Equator and the amount of rainfall that they receive.

For today's Lesson all you'll need is a pencil, some paper and your brain.

Please take a minute now, to clear away any distractions, including turning off any apps or conversations that you have running in the background, if you know how.

Finally, if you can try to find a quiet place where you won't be disturbed during this lesson.

Pause the video now, so that you can get the things you need and find a quiet place to work.

Great, now you have everything you need, let's carry on.

So, we are geographers, very, very importantly.

Geographers are types of scientists who study the earth.

Now this includes the land, the physical features and the people who live within the land.

And this is what we call the human features.

So in this lesson, we are going to be asking, what is a biome? We're going to be studying the six major biomes and then we'll be asking, how does climate impact a biome? So what is a biome? Well, a biome is a large area of land with a particular climate, types of plants, which we call flora and animals, which we call fauna Let us recap that, I say flora, you see plants, flora, flora, flora, plants, well done saying flora, I say fauna you say animals, fauna, fauna, fauna, animals, well done.

Let's recap, the definition of a biome one more time.

Say it with me, a biome is a large area of land within a particular climate, types of plants, flora and animals fauna, great work.

Here's your first task.

You need to complete the sentence, using the keywords to help you.

A biome is a large area of, with a particular types of plants and animals.

The keywords to help you ore flora, climate fauna and land.

Pause the video now so you can complete that sentence.

How did you get on, let's check the answer.

A biome is a large area of land with a particular climate types of plants, flora and animals fauna, give yourself a pat on the back, if you got that right.

You can pause the video now so you can tick or fix your answer.

Well done let's move on.

So a biome is different from an ecosystem.

An ecosystem, is the interaction of living and nonliving things in an environment.

A biome is a specific geographic area that is defined by the species living there.

A biome can be made up of many ecosystems. For an example, an aquatic biome, can contain ecosystems such as coral reefs and kelp forests.

So here's a question for you or even a statement, a biome and an ecosystem are the same thing, true or false? Shout it out.

Absolutely, that is false because a biome is a large area of land or geographic area.

And ecosystem is about the interaction between living and nonliving things and there can be lots of ecosystems within a biome.

So here is a map, let's take a closer look.

This map uses a colour key, to outline the many different types of biomes.

And this map shows 18 different types of diverse biomes.

Here you can see the colour key on the left hand side, we have the colour and then we have the name of the biome next to it.

Now the exact number of biomes is widely debated.

We are going to study six major biomes, but it is helpful for us to know that within the six major biomes, there is great diversity.

You can see that I have underlined the names of the six major biomes.

For example, the tundra is one of the six major biomes.

The tundra is coloured in this light blue colour, and I can find it on the map up here, so I can see it's in some of the coldest regions of the earth.

I can also see the tundra situated up here.

Can you put your finger on the other five major biomes that I underlined in green now? Pause the video while you put your finger on the names of the five other major biomes.

Did you work them out? Let's have a closer look again.

So, we've got the taiga.

Did you get that one right? Give yourself a pat on the back, we have the temperate broadleaf forest.

This is sometimes called a temperate deciduous forest.

So when we look for the taiga, I can see that there is this very dark green colour, and that is situated in this part of the world, which is in across Canada.

And I can see across Northern Europe and Northern Asia, there is also a large area of taiga.

The temperate broadleaf for us is this light green colour.

And I can see it in North America, across Europe, across Asia, down here in Australia and New Zealand.

And even down here in South America, which is currently underneath the bar.

You will have also seen the desert, the grass savanna and the tropical rainforest underlined.

Well done for identifying those.

Now, this map also outlines where the Equator is.

Now the Equator is the imaginary line that runs throughout the centre of the earth.

Can you put your finger on the line of the Equator? Did you put your finger on this line here? Great work, everyone.

You should also be able to see, the line that sets that situated at 30 degrees North.

Can you put your finger on that line? Absolutely, it is here and 30 degrees South is this line here.

We can see that this pink line is the Tropic of Capricorn and this purple line is the Tropic of Cancer.

Now those we will return to later.

Now these lines are called latitude lines and they help geographers to measure the distance of a place, on the earth from the Earth's Equator.

Let's turn my pointer off.

Okay let's carry on.

Now, we need to answer this question.

How many major biomes are there? Are there six, 16 or 18 Pause the video now so that you can write down the correct answer.

Did you get the answer right? Let's have a look, the answer was six.

Thumbs up to you if you got the right answer.

You can pause the video now, so you can tick or fix your response.

Let us move on.

So we're going to have a closer look at the six major biomes.

The first is the tropical rainforest.

Let's have a look at the key features.

So the key features are better.

Tropical rainforest has a very steady temperature.

It's always between 20 degrees Celsius and 25 degrees Celsius so very warm all year round.

It's also rains all year round and we'll have a look at why that is later in this lesson.

The trees are very tall and varied.

That means there are lots of different types of trees within a tropical rainforest.

Most of the plants are evergreen, not deciduous.

Now evergreen means that the leaves do not fall off the trees.

While deciduous means the tree sheds its leaves annually.

For example, in England, we have many deciduous trees and they shed their leaves during autumn.

Here's some true or false statements.

One, it's rains all year round in a tropical rainforest.

Two, trees are small and very similar.

Three, most plants are deciduous.

Now these statements are about tropical rainforest.

You need to write the number of the question and write either true or false next to the number.

Pause the video now so you can complete that task.

Let's see how you got on.

So number one, it rained all year round in a tropical rainforest, that's true.

Two, trees are small and very similar, that's false because trees are tall and very varied.

And three, most plants are deciduous, that's false.

Most plants of trees are evergreen.

Pause the video now, so you can tick or fix your answer.

Excellent work, let's move on.

The next biome is the temperate deciduous forest.

It's sometimes called a temperate broadleaf forest.

And that's because the leaves in this type of forest are broad.

So the key features.

well, the temperature ranges from between minus 30, so it can get very cold, to 30 degrees celsius.

It goes through all four seasons.

Can you name all four seasons? That's right, winter, spring, summer and autumn.

And there are a range of trees, but most lose their leaves in autumn because they are deciduous trees.

There is even rainfall throughout most of the year.

Here is a question or statement thinking about the last biome we learned about, think about the statement, most trees are deciduous.

What does deciduous mean? Shout out your answer.

That's right, deciduous means that the leaves fall off the trees annually.

Well done, give yourself a pat on the back.

So the coniferous forest or a taiga.

Well, in a taiga, not the animal of course, the coniferous forest, the temperature ranges from minus 54 degrees Celsius, so it gets very cold and 30 degrees Celsius, so it can be quite warm.

It has a low average temperature.

So that means, generally throughout the year, the temperature is cold.

Most of the trees are evergreen, so the leaves don't fall off.

It is the largest land biome so out of all of the biomes, most of the land is covered, in the taiga forest, it makes up the largest land biome.

So here are some true or false statements again, These are all about the taiga, the coniferous forest.

The temperature ranges from minus 30 degrees Celsius and 30 degrees Celsius.

Has a high average temperature.

It is the smallest land biome.

Pause the video now, so you can write true or false next to these statements.

Let's have a look at the answers.

Temperature ranges from minus 30 to 30 degrees Celsius.

That's false because it ranges from minus 54 to 30 degrees Celsius.

Has a high average temperature, that's false.

It has a low average temperature.

And number three is also false because it is the largest land biome.

Pause the video now so you can tick or fix your answers.

Well done everyone, let's move on.

The tundra, key features are, the temperature ranges from minus 34 degrees Celsius and six degrees Celsius.

So generally it's very cold here.

It is the coldest of all the biomes.

There's little rain, lots of frost and permafrost.

Now permafrost is a thick subsurface layer of soil, that remains below freezing, so bellow zero, throughout the year.

Now this occurs in many polar regions and that's why it's the coldest of all biomes.

There are no trees, generally and only a few small plants and that's because of the permafrost.

What is the temperature range in the tundra? Do you remember? Shout it out, have a go, that's right, it's between minus 34 degrees Celsius and six degrees Celsius.

Give yourself a pat on the back.

Okay, the grasslands or the savanna, as it's sometimes called.

Key features, has a dry season and a rainy season.

The temperature ranges from minus 40 degrees Celsius, that's generally at night and it can be over 40 degrees Celsius in the daytime, it gets very, very hot.

Mostly grass grows and the occasional individual tree, as you can see in this image.

You need to answer the question.

Can you list two features of a grassland? Pause the video now and see if you can remember, two features of a grassland.

Did you remember two features? Let's have a look.

You could have said it has a dry and a rainy season.

You could have said the temperature ranges from minus 40 degrees, Celsius to 40 degrees Celsius.

You could have said mostly grass grows and the occasional individual tree.

Pause the video now, so you can tick or fix your answer.

Let's move on.

So the desert, The key features are that it has temperatures over 50 degrees Celsius in the day and below freezing at night.

Has a real range of temperatures.

There are very few clouds and very little rain.

And that's why, there are very few plants here or animals.

There are very few plants or animals because it is so dry.

So, why is it so dry in a desert? You can shout the answer out, that's right, because there are very few clouds and little rain.

So now we've learned about the six major biomes.

We're going to think about how does climate impact a biome? Well, the global pattern of biomes is controlled by climate.

The diagram on the right shows, how climate is controlled by convection currents.

Now convection currents are when, warm at rises because it is less dense.

Warm air rises because it is? That's right, less dense, warmer is less dense as the warm air rises it cools.

as it becomes more cool, it becomes cooler and cooler, as it reaches the outer atmosphere.

It then, sinks because cold air is more dense.

Cold air sinks because it is? That's right more dense.

Now, hot air balloons use this principle.

By heating the air inside the balloon, the air becomes less dense.

What does the air become? Less dense absolutely, because it is warm and it's warmer than the surrounding air and so the balloon rises.

Complete the sentence.

Warm air because it is, cool because it is, dense.

Pause the video now and complete the sentence.

Let's see if you wrote the correct words, in the correct spaces.

Warm air rises because it is less dense.

Cool aIr sinks because it is more dense.

Pause the video now, so you can tick or fix your answer.

Excellent work everyone, let's move on.

So, the Amazon Rainforest is located across the countries, situated to the Northwest of South America.

These include Brazil, Suriname, Guyana, Venezuela, Columbia, Ecuador, Peru, and Bolivia.

The rainforest sits on and around the Equator, the imaginary line that runs around the centre of the earth.

And as a result of the sun's light, being more concentrated near the Equator, the land and the oceans on and around the Equator are much hotter.

As the oceans are heated, the water heats up the water then evaporates and rises with the warm air.

And as it rises, it cools.

The water then condenses and becomes liquid again.

And this is how clouds form.

As more and more air cools and more and more water condenses.

The clouds become heavy with liquid until they can no longer hold the liquid and it rains.

This cycle happens continuously at the Equator, which is how tropical rainforest are created.

The climate is perfect for the growth of a hugely diverse range of vegetation, because there are high levels of sunlight all year round and high levels of rain to support growth.

Antarctica on the other hand, is located at the South Pole.

The South Pole is very cold because it doesn't get any direct sunlight.

The sun is always low on the horizon, even in the middle of summer.

In fact, in winter, the sun is so far below the horizon that it doesn't come up at all for months at a time.

This means that the ocean surrounding Antarctica is also very cold.

And that means that the water does not heat up and evaporate as it does in the oceans, in and around the Equator or on and around the Equator.

And this is why there are extremely low rainfall over the Poles.

So this image shows us how global convection currents move around the earth's surface.

Warm air rises over specific locations on the earth, carrying water as an evaporated gas.

The rain then condenses or the water then condenses as the air cools and as the water cools, it forms clouds and rains over specific locations.

We find deserts close to the Equator where dry air falls such as in the North of Africa, where we find the Sahara Desert and the South of South America, where we find the Atacama Desert.

The Atacama Desert is located south of the Amazon Rainforest.

The rain falls over the rainforest and then dry cool air sinks over the desert, which is why there's so little flora and fauna there.

The same thing happens in the Sahara Desert.

You can see the area of green under the desert, which shows us, where the rain falls over Africa and encourages the growth of tropical rainforests.

By the time the convection currents have moved North, the air no longer contains any or very little if any water is very little and hence the creation of deserts.

We've got three different areas here.

The Antarctica, the Amazon Rainforest and the Atacama Desert.

We have also got three descriptions, let us take a closer look.

The climate is perfect for the growth of a hugely diverse range of vegetation, because there are high levels of sunlight all year round and high levels of rain to support growth.

B, rain falls over the rainforest and then dry cooler air sinks, over this biome, which is why there's so little flora and fauna here.

It is hot as it is close to the Equator and so receives direct sunlight.

C, the climate is very cold.

The ocean's water does not heat up and evaporate, as it does in the oceans on and around the Equator.

So there is extremely low rainfall over this area.

Your job is to match the area with the description of the biome.

You don't need to write out the whole description.

You just need to write the number and match it to the letter.

Pause the video now and complete that task.

How did you do? Let us check the answers.

So Antarctica, number one matches to C.

The Amazon Rainforest matches to A And number three the Atacama Desert matches to B Pause the video now, so you can tick or fix your answers.

Excellent work everyone.

That brings us to the end of today's lesson.

A really big well done on all the fantastic learning you've achieved today and if you're able to, please take a picture of your work and ask your parents or carer to share it with your teacher, because I'm sure they'd love to see it.

And if you'd like, ask your parents or carer to send a picture of your work to, @OakNational on Twitter so that I can see your lovely work too.

That's all we've got time for today.

I'll see you for the next lesson.