Lakes & Ponds

Mrs. Wisher

Ponds

Ponds are more shallow

Sunlight reaches the bottom of ponds

Ponds have muddy bottoms that support plant growth

Some ponds are seasonal

Pond Life

Algae live in ponds which produce food for other animals

Frogs, fish, snails and crayfish all live within a pond

Blue-green algae

Ponds

In many northern states, ponds will freeze during winter

Fish and plant life can live under frozen water due to the warmer temperatures

Why does only the surface of the pond freeze?

Lakes

Lakes are deeper and larger than ponds

Sunlight does not reach the bottom of lakes

The bottom of lakes are either sand or rocks

Lakes & Ponds What’s the difference?

Lakes are large bodies of water that are within land

Ponds are smaller than lakes

Lake Formation

Lakes can be formed from:

glaciers

oxbow

volcanoes

reservoirs – for human use

How was this lake formed?

How was this lake formed?

Lake Habitats

Close to shore, lake habitats are like ponds

Few organisms live at the bottom of lakes

mostly worms & mollusks

Large bony fish live in the deep waters of a lake

eat what floats to the bottom

Lake Turnover

Most lakes change with the seasons

Lake turnover happens in the winter when the warmer water cools and sinks to the bottom causing the water & nutrients to mix

Eutrophication

Algae feed on waste products from other animals

Over time more algae grows and covers a lake in a thick green scum which blocks out sunlight

Plants die and the lake is starved of oxygen

The lake becomes shallower and will eventually disappear

Wetland

A wetland is a shallow swampy area that can sometimes evaporate during warmer weather