Aquatic Ecosystems and Succession

1. Aquatic Ecosystems and Succession

2. Aquatic Ecosystems • The different aquatic ecosystem are determined by the depth, flow, temperature, and chemistry of the overlying water. • The two main differences between aquatic ecosystems is whether or not they contain salt. • Freshwater ecosystems do not contain salt. • Marine ecosystems contain salt. • Estuaries are where a river meets the ocean and contains both fresh and salt water.

3. Freshwater Ecosystems • Only 3% of water on the Earth’s surface is fresh water. Freshwater is grouped into . . . • Flowing Water (rivers, streams, and creeks) • Standing Water (ponds and lakes) • Wetlands (bogs, marshes, and swamps)

4. Marine Ecosystems • Some wetlands contain salt water, but most of our salt water ecosystems are found in the ocean. • The ocean is broken up into zones based on the depth and distance from the shore. • Where there is sunlight many plants can be found growing on the ocean floor as well as coral reefs and aquatic life that feeds on these plants. • In areas with less sunlight life must find a different way to survive.

5. Succession • Ecosystems are constantly changing in response to natural and human disturbances. • The series of changes that occur in an ecosystem over time is called succession. • There are different two different types of succession: • Primary • Secondary • Succession follows a predictable pattern

6. Succession • Pioneer organisms are the first organisms to inhabit a new area and are typically smaller plants like lichens (fungi and algae mix) • When these organisms die they create nutrients that other plants like mosses and grasses can use to grow in. • Each new organism alters the environment making it possible for the next to inhabit it. • The final stage is called the climax community which is a relatively diverse and stable ecosystem

7. Primary Succession • Primary succession occurs on surfaces where no soil exists (there has been no previous life) • After a volcanic eruption and the Earth is covered in igneous rock • New islands formed by volcanoes • Bare rock exposed after glaciers melt

8. Secondary Succession • Secondary succession occurs when a disturbance of some kind changes the ecosystem without removing the soil. • Wildfires • Abandoned farms • Drastic climactic changes

9. Succession in Marine Ecosystems • Succession can occur in marine ecosystems as well. • Some organisms leave things behind that can become a home for other species. • When a large blue whale dies and sinks to the barren ocean floor it creates food for other organisms and the skeleton may become a home • Coral reefs are created in this manner