Salt marshes are common along the seacoast, inside barrier islands and beaches and in estuaries.Salt marshes often extend many miles inland and are subject to tides.

• 反之，一些靠皮肤呼吸或吸收营养的动物，如海星、海 胆，以及许多鱼类，由于泥土可能盖住它们的鳃，它们很难生存。