What is a key feature of Lakes?

A key feature of lakes is that they are completely surrounded by land. This definition distinguishes them from other bodies of water such as rivers, which flow and are not enclosed by land, or oceans, which are vast bodies of saltwater not encircled by land. Lakes can vary greatly in size and depth, but their defining characteristic remains that they are enclosed ecosystems that do not have direct coastal boundaries like seas or oceans.

Connections to oceans, while possible in some cases for specific bodies of water, are not a defining feature of lakes. Additionally, ocean tides affect coastal areas and bodies of water that are adjacent to oceans but do not impact lakes, which are inland. Lastly, characterizing lakes as primarily seasonal water sources does not accurately reflect the permanent nature of many lakes, which can be present year-round regardless of seasonal changes. Thus, the distinctive feature of being completely surrounded by land solidifies the understanding of what constitutes a lake.