Lesson video

Hi, I'm Miss Miah.

Thank you so much for joining me in this lesson today.

Let's get started.

In this lesson, you will be able to explain how growing crops for food is linked to the loss of habitats and a decrease in biodiversity.

Your keywords are on the screen now.

You can write them down if you'd like to.

So we've got agriculture, deforestation, habitat, biodiversity, ecosystem.

Great.

Let's find out what these words mean.

Agriculture: using land to raise farm animals and grow crops to feed humans and farm animals.

Deforestation: the removal of trees, often to use the land for agriculture or building.

Habitat: the place where an organism lives, which provides the organism with food, shelter, and a place to reproduce.

Biodiversity: the range of different living organisms or species in an ecosystem.

Ecosystem: all the living organisms in a place, interacting with each other and their non-living surroundings.

Super.

Let's move on.

So this lesson is all about agriculture and habitat loss.

We've got two lesson cycles today.

In in our first lesson cycle, we'll be looking at food production and habitat loss.

And then lastly, we'll be looking at reducing habitat loss due to agriculture.

I'm super excited about this.

I'm super excited about this lesson.

I hope you are too.

Let's begin.

So on the left here, we have an image of a very crowded market.

We have to produce a lot of food to feed the 8 billion people in the world.

The food we eat is made from: crops, edible plants and fungi, or animals that ate crops.

Producing food depends upon agriculture.

Agriculture means using land to: raise farm animals, grow crops for farm animals to eat, grow crops for people to eat.

The graph shows population of the world over the past 12,000 years.

Let's have a look.

What can we conclude from the data in the graph?

The population was relatively small for most of this time.

There has been a rapid increase over the last 200 years.

As the human population size increases: more food is needed, more land must be used for agriculture.

Over to you.

Who was correct?

A: Andeep, "The human population is going up, so we have to use more land for food production.

" B: Sam, "The human population is decreasing, so less land is needed for producing food.

" And C: Izzy, "The human population is relatively small now, so we don't use much land for agriculture.

" What do you think?

You can pause the video here and click play once you've got the answer.

So how did that go?

Well, you should've got A, Andeep is correct.

The human population is increasing.

So due to this, we're going to have to use more land for food production.

Let's move on.

Converting land to use it for agriculture is a major cause of deforestation.

Here we have an image of a forest.

Many species of plants and animals live here.

The trees are cut down or burnt.

Farmland: few species, mainly just crops.

Forests are an important habitat for many species of plants, animals, and fungi.

A habitat provides food, shelter, and a place to reproduce.

So when deforestation occurs or when a forest land is converted into farmland, the original habitat is lost.

Few species remain as their habitat is gone.

Here's an example: Palm oil.

Producing palm oil is a major cause of deforestation.

Palm oil is extracted from some species of palm trees.

Palm oil is actually used in many common foods that you can see here.

So here we have a forest and can you see the deforestation that has occurred there?

So the palm trees are grown in large plantations after deforestation.

So species such as the Sumatran Orangutan are now critically endangered due to the loss of the habitat through deforestation or palm oil production.

Back to you.

Which of the following is not a major cause of deforestation?

Is it A: producing palm oil?

B: planting new trees in empty land?

C: clearing land for agriculture?

Or D: building roads through forests?

What do you think?

You can pause the video here and click play once you've got the answer.

So what did you get?

Well, B is correct.

Planting new trees in empty land is not a major cause of deforestation.

Well done if you've got that.

Let's move on.

Task A.

Palm oil, as you know, is used in many common foods.

Producing palm oil is a major cause of habitat loss due to deforestation.

The table shows that greenhouse gas emissions caused by deforestation during the production of various oils.

So on the left in this table we can see oil, the oil type, so we've got soybean oil, palm oil, sunflower oil, and olive oil.

And then on the right here we've got emissions, kilograms gas per kilogram food.

So we've got 2.

9, 2.

8, 0.

12 and zero for olive oil.

I'd like you to write some guidance to a shop owner who wants to sell forest-friendly snacks.

You can pause the video here and click play once you've completed this task.

So how did that go?

Well, you may have written something like this.

Try to avoid selling snacks that contain palm oil such as crisps, pizza, donuts, biscuits, chocolate and ice cream.

If you do sell these snacks, try to sell brands that are made with sunflower oil or olive oil instead of palm oil or soybean oil.

Producing sunflower oil and olive oil involves less deforestation and produces lower greenhouse gas emissions than palm oil and soybean oil.

Well done if you included some of these key points.

Let's move on.

Lesson cycle two.

We're now going to be having a look at reducing habitat loss due to agriculture.

Let's get started.

Now, biodiversity is the range of species living in an ecosystem.

As you know, forests are important habitats that support many species of plants, animals and fungi.

The biodiversity in a forest is high.

All the species in a forest ecosystem depend on each other to survive.

For example, through food chains.

Deforestation removes shade and shelter for other plants and animals and disrupts food chains.

Many of the plants and animals that depended on the forest habitat will not be able to survive.

If the forest is replaced by a farm field, the field may have a lot of crops growing in it, but it's just one species, which means the biodiversity is low.

Conversion of land for agriculture is a major cause of habitat loss and biodiversity loss.

Many species of plants, animals, and fungi are affected and some may go extinct.

Threatened species include pollinators.

Many crops cannot be grown without pollinators to fertilize their flowers.

On to our check for understanding.

So I'd like you to complete the sentences below.

You can only choose from the words "decrease" and "increase.

" So deforestation causes a- in the number of trees, the number of other plant species is likely to.

.

.

The number of animal species is likely to.

.

.

And lastly, the biodiversity of the area is likely to.

.

.

You can pause the video here and click play once you've completed this check for understanding.

So how did that go?

Let's have a look.

So deforestation causes a decrease in the number of trees.

The number of other plant species is likely to decrease.

The number of animal species is likely to decrease.

And lastly, the biodiversity of the area is likely to decrease as well.

Well done if you managed to get that correct.

Let's move on.

What can we do to reduce habitat loss due to agriculture?

Positive land use change, so ecosystem restoration, can help to replace lost habitat and lost biodiversity.

So here we have reforestation.

Regrowing trees on land that is no longer used for agriculture, allowing native species to regrow on parts of farmers' land.

These strategies only replace a small proportion of the habitat and biodiversity lost due to agriculture.

We can have a bigger impact by changing our diets.

A lot of habitat is lost due to converting land to rear animals.

If we all eat less meat, this will reduce the demand for land for rearing animals.

This land can then be used to grow crops to feed us or rewilded and reforested.

Back to you.

Which strategy is likely to have the biggest impact on replacing lost habitat and lost biodiversity?

Is it A: many people eating less meat?

B: deforestation?

Or C: rewilding?

What do you think?

You can pause the video here and click play once you've got the answer.

So what did you get?

If you got A, you are correct.

Many people eating less meat will have the biggest impact on replacing lost habitat and lost biodiversity.

And that's because there will be less deforestation.

Let's move on.

Task B.

A farmer is rewilding some of their land which was once used to grow wheat.

Native plants, including flowers and trees, are regrowing on this land.

I'd like you to explain how this will help to restore lost biodiversity.

And on the right here, we can see a photo of rewilding farmland.

Think about everything we've discussed in the previous slides.

You can pause the video here and click play once you've completed this task.

So how did that go?

Well, let's have a look.

You may have said something like this.

The original habitat will be restored, at least partially.

This will provide shade, shelter, a place to reproduce, and food for many species, and flowers will support pollinators.

This will enable many more species to live in the area, which, as a result, will increase the biodiversity of the area.

Well done for completing this task.

We've now reached the end of this lesson.

Let's summarize our learning.

So this lesson was all about agriculture and habitat loss.

You now understand that we have to produce a lot of food to feed the increasing human population, and this requires using a lot of land for agriculture.

Converting land for agriculture use is one of the major causes of deforestation worldwide.

Deforestation results in habitat loss for many species in the ecosystem.

Conversion of land for agriculture is a major cause of habitat loss and biodiversity loss.

Strategies that can help to reduce habitat loss and biodiversity loss include changing diets to eat less meat and positive land use change such as reforestation and rewilding agricultural land.

Thank you so much for joining me in this lesson.

Bye!