_:b1218104 "PLB:plb"^^ . _:b1218104 . _:b1218104 "ISBN-10:0618455043"^^ . _:b1218104 "Expressions of the estuarine biome occur at wide lower courses of a rivers where they flow into a sea. Estuaries experience tidal flows and their water is a changing mixture of fresh and salt."^^ . _:b1218104 . _:b1218104 .