The reasons for dominance of vascular plants on land are:
(a) Presence of deep, penetrating and wide spreading roots which anchor the plant and also absorb water and mineral salts.
(b) Covering of aerial parts with water proofing material like cudn in living tissues.
(c) Occurence of mechanical tissues to provide support to aerial parts and to allow them to rise to great heights.
(d) Presence of long distance transport system in the form of vascular tissues.