Page 36 - 新思维科学学生用书5 样章

Project

Project: Pollinators and pesticides

This project has two parts. You must do Part 1 and then choose either Part 2 or Part 3.

Part 1

Read about how pesticides can harm pollinators. Then discuss the questions in a group.

Honeybees are important pollinators. The bee in the picture is pollinating onion
flowers. Bees also pollinate the flowers of many other food plants, such as apples,

potatoes and beans. In fact, 80% of the plants we eat are pollinated by bees.

Farmers and gardeners like pollinators but they don’t like insects, snails, worms and
other pests that eat their plants. They often use chemicals called pesticides to get rid

of the pests.

Why are pesticides a problem? The pesticides kill the pests, but they also harm
pollinators. Pesticides that are sprayed onto plants often cover the flowers. When

bees visit flowers to look for nectar and pollen, they take in the pesticides along
with their food. Pesticides on seeds can also harm bees. When the seed grows, the

pesticide spreads to the whole plant, including the pollen and nectar.

Some pesticides kill the bees. Other pesticides make it hard for the bees to fly and to
find their hive or to find other flowers to feed on. Pesticides can also make the bees

have fewer young.
How can we help pollinators? We should try not to use

pesticides in and around our home and encourage

other people to do the same. People should use
pesticides only when they are needed, for

example if their plants are badly attacked

by a pest. They should not use them when
the plants are flowering. Some pesticides are

sprinkled onto plants or soil as a powder. These

pesticides seem to be more harmful than liquid
spray pesticides, so people should try not to use them.

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