**2.1 Zonation in lentic systems**

The bodies like ponds and lakes have three zones (**Figure 3**):


#### *2.1.1 Littoral zone*

The area of shallow water is where light can reach the ground. This area is often identified by the presence of rooted plants because it receives a lot of sunlight. This might not apply to "managed" or "man-made" lakes or ponds.

#### *2.1.2 Limnetic zone*

The compensation level is the area of open water up to the depth of effective light penetration. The depth at which the rate of respiration and photosynthesis are equal is known as the compensation level. This depth will typically be at the point when light intensity is 1% of that of full sunlight. Only planktons, nektons, and occasionally neustons make up the community in this zone. Small, shallow ponds lack this zone. The term "Eutrophic Zone" refers to the entire lighted stratum, including the littoral and limnetic zone.

### *2.1.3 Profundal zone*

This is the deep bottom region, past the point at which light can effectively penetrate. Ponds frequently lack this zone.
