Ecological Succession AQUATIC ECOSYSTEMS Ecological Succession n n

Ecological Succession: AQUATIC ECOSYSTEMS

Ecological Succession n n The class has covered Terrestrial Succession -the natural changes occurring in ecosystems on land. There are many types of ecosystems in water, including coral reefs and salt marshes.

n n Ecological succession also occurs in aquatic ecosystems. Bodies of water will undergo a series of changes until they reach the climax community, the same stable stage reached after terrestrial succession.

Aquatic Succession n n - begins along the shorelines of bodies of water Leaves and sediments accumulate along the edges and on the bottom, making the body of water smaller and more shallow

Along the shore n n n - cattails and other aquatic plants grow in the sediment. These plants trap more sediment. Bushes can grow in this area now.

As more soil is produced n n - the area can now support trees. These are trees that can tolerate wet soils and bright sunlight.

As more shade is made n - other trees move in, as in terrestrial succession. Remember, the trees of the climax community produce saplings that can grow in the shade of other trees.

The climax community after aquatic succession n n - will depend upon the surrounding ecosystem. In a temperate forest biome, ponds and lakes will eventually fill in and become part of the surrounding temperate forest.

The speed at which succession occurs n n - depends upon the size of the body of water: For example, the Great Lakes are undergoing succession, but will not be forests in our lifetimes.

Other examples are n n - fast running rivers that don’t allow sediment to accumulate, -deep lakes in area where there is little sediment accumulating

Smaller bodies of watern -and bodies of water near extensive erosion will undergo succession more rapidly than larger bodies of water

The rate of aquatic succession is increased by: n n Human activity Organic pollution from sewage treatment plants entering streams and lakes Fertilizers that run off into water (eutrophication). Animal waste products also may add organic nutrients to water.

What can be bad about fertilizer and other organic nutrients? n n n These nutrients cause algae to grow unchecked. These are called algae blooms. Algae blooms block sunlight from reaching the rooted plants underneath. Eventually, algae die and the decomposition uses up oxygen, killing some species.

Algae blooms n n Cause rapid aging of lakes Therefore, smaller lakes and lakes near human settlements undergo aquatic succession more rapidly.

Aging of lakes due to excessive nutrientsn n n -is called eutrophication It can happen naturally, but it will happen slowly (occurring on geologic time scales) Human-induced eutrophication happens quickly (within a few years)

Stages of Aquatic Succession Overview Watch the following videos: Pond Succession #1 Pond Succession #2