Changes to food chains

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3. TRY this:

Q1: What kind of river is best for encouraging many species, a natural one or a straightened one?

[Answer]

People can have a terrible effect on other living things. For example, by farming they can take away the food for many other living things.

By straightening out rivers they can also damage the environment of living things. A natural river channel has deep pools and shallows, it has shade and open ground. Many plants can grow and so many food chains can form. When a river is dredged and straightened, most of this is lost.