The zone in a lake or pond between the LITTORAL and PROFUNDAL zones, extending from the edge of the area occupied by rooted plants to a depth of about six to ten meters, where the water temperature declines.

• 亚沿岸的：湖或池塘内位于沿岸区和深水区之间的区域，可从有根植物生长区域的边界延伸至七到八米深处，此处水温会下降。