is the disintegration or decay of rocks on the surface of the earth.
There are three kinds of weathering: mechanical
(which involves no chemical change to the rocks, e.g. by freeze/thaw
action), chemical (where chemicals decompose
the rock e.g. carbonation - see the Burren photographs)
and biotic (where plants or animals produce
the breaking down of the rocks e.g. by the action of roots). The action
of plants in this photograph show the impact of biotic weathering.