Page 30 - 新思维科学学生用书2 样章

1.4 Rocks and the environment

River bed

A river bed is a place where we dig stones.

We use spades and big diggers.
From rivers we dig sand, gravel and pebbles.

When people dig up rocks they damage the

environment. Trees and other plants

are killed, animals are killed and lose

their homes. Look at this picture.

There was once a forest, a home

for hundreds of animals and plants,

now there is a hole with only a few

animals and plants living there.

Question

4 Close your eyes and think about working in a mine. It would

be dirty, hot and dangerous. What might you see?

Using water to sort stones

We can use water to sort small

rocks. A stone is another name

for a small rock.

The moving water in the bowl

sorts lighter, smaller stones from

the larger, heavier stones.

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