Afforestation leads to both air and water conservation, as well as soil conservation. How?

Afforestation aids in air, water and soil conservation in following ways:

1. Air Conservation - Plants take in carbon dioxide from the atmosphere and give off oxygen. Also, they reduce dust particles from the air.
2. Water Conservation - Plants increase the level of groundwater.
3. Soil Conservation - The roots of plants hold the soil firmly which prevents soil erosion through rain water or wind.