Under Your Feet

7

Greenhouse gases

The Earth is heating up,

which causes fires, droughts,

and floods. We call this

global warming. The three

main “greenhouse” gases

that cause it are carbon

dioxide (CO

2

), nitrous oxide

(N

2

O), and methane (CH

4

).

Farm wisely

Farmers plough soil

to kill weeds. Ploughing

also breaks the soil up,

which releases nutrients to

help seeds grow. However,

too much ploughing destroys

soil life and releases

greenhouse gases. Many

farmers are choosing to plough

less to help solve this problem.

Make airy compost

Most nitrous oxide and methane

is made by microorganisms that

do not have enough oxygen (a gas

found in the air). Compost heaps

need lots of dry leaves, twigs, and

other materials that let in air for the

microorganisms to breathe.

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