An aquatic habitat is a habitat with water. It includes areas that are permanently covered by water and surrounding areas that are occasionally covered by water.

The water in the estuary contains small pieces of plants, detritus (waste or debris of any kind), microscopic organisms, and algae in the water. Water is more salty closer to the sea, less salty as you move up the river. Salt in the water makes the water heavier than freshwater. This is why it is easier to float in ocean water than a lake. At the bottom of an estuary, the soil or mud is thick and deep. Small organisms live and breathe in the top layers of mud, which contains some oxygen. Many plants live in different parts of the estuary. Some plants grow in marshes, their roots grow in the mud, and the stem submerged when the tide comes in.

Notes on Surface and Ground Water
Worksheets

Natural events affect aquatic environments.

Tides affect salinity (amount of salt ). Rising levels of ocean water at the shore pushes more saltwater up into the estuary and river. During low tide, ocean water draws back from the estuary.
Flooding causes the estuary to get more freshwater from the river. When a river floods it deposits nutrient rich sediment on the banks, bits of vegetation washes into the water and become food for aquatic organisms. Floods replenish lakes and ponds, it raises the water table.

Flood through extreme events can be detrimental to aquatic system until balance is reached.
Worksheet

Human Activities affect aquatic environments.
Human activities affect aquatic environment in the most disruptive way.

These activities affect the water cycle, interferes with the level of streams and flow of water, drain wetlands, and eliminate aquatic organisms. Some of these activities uses a lot of our water resources such as oil sands and mining.

When people build dams, they change freshwater ecosystems from a flowing system into a still system.

All life is made of water and needs water. Water is our most threaten resource. The decreasing amounts and polluted, unsafe water is leading to sickness and death. This is the most important reason we should protect our aquatic habitats and all habitats.
Learn more of this under the topic of ecosystems and cycles.

Discussion
Make a list of things that live in estuaries and rivers. Discuss how a few of these things would fare if the water they live in was saltier, or if there was a flood. Go to the CHAT. Click on the link below.

Essay: Write a short paragraph explaining why you think it is important to save Earth’s Coral reefs.