_:b1216427 "Wikipedia:Alluvial_plain"^^ . _:b1216427 "Arelatively flat and gently sloping landform found at the base of a range of hills or mountains, formed by the deposition of alluvial soil over a long period of time by one or more streams coming from the mountains."^^ . _:b1216427 . _:b1216427 . _:b1216427 .