Why does deforestation increase the amount of greenhouse gases in the atmosphere?

deforestation increases the amount of green house gases for 3 main reasons.

1)Trees are cut down and removed therefore they cannot photosynthesis in which carbon dioxide (CO2) is converted to oxygen (O).

2)Trees may be cut down and left they then rot the rotting of the trees lets the CO2 be released and adds to the greenhouse gases.

3)The trees may be burnt which is also releasing CO2 into the atmosphere.

The greenhouse gases are methane, carbon dioxide and a little bit of water vapour.