"alluvial plain"^^ . "ENVO"^^ . . "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."^^ . "ENVO:00000258"^^ . "Wikipedia:Alluvial_plain"^^ . "EcoLexicon:alluvial_plain"^^ . . "SWEETRealm:AlluvialPlain"^^ .