Lesson 2 Aquatic Ecosystems Study Guide
Name __________________________________________________
Answer the following questions in complete sentences. Failure to answer in complete
sentences will result in a loss of points.
1. Define aquatic ecosystem.
An aquatic ecosystem includes any water environment and the community of organisms that
live there.
2. What are the three main types of aquatic ecosystems and define each?
a. Freshwater ecosystems contain fresh water.
b. Marine ecosystems contain salt water.
c. Estuaries contain a mixture of both fresh and salt water (brackish water)
3. What are the seven abiotic factors that have an effect on an aquatic ecosystem?
The seven abiotic factors that have an effect on aquatic ecosystems are water temperature,
water depth, amount of sunlight, oxygen level, water pH, salinity (level of salt), and the rate of
water flow.
4. What are wetlands?
A wetland is area of land that is saturated, or soaked, with water for at least part of the year.
5. List and describe three functions of wetlands?
Wetlands are responsible for flood and erosion control, filtering out some pollutants from the
water, and provide habitats for the organisms that live there.
6. How does oxygen get into the water?
Oxygen gets into the water from two sources. The first source is the plants that live under the
surface of the water (through the process of photosynthesis). The second way that oxygen
gets into the water is where the surface of the water comes into contact with the atmosphere.
The water can absorb oxygen directly from the atmosphere.
7. What would be some adaptations an organism would need in order to survive in an
estuary?
Some adaptations that organisms would need in order to survive in an estuary would be the
ability to deal with changing salinity levels, the ability to remove excess salt, and the ability to
consume organisms that are adapted to living in brackish water.
8. What are the three areas that make up a marine ecosystem and define each?
a. The coastal ocean which is the area from the shoreline to the continental shelf.
b. The open ocean which is the area from the shelf to about 2,000 meters deep.
c. The deep ocean which is deeper than 2,000 meters.
9. List and define the four ocean zones.
a. The intertidal zone is the land between high and low tides.
b. The neritic zone is the area from the shoreline to the edge of the continental
shelf.
c. The bathyal zone is the area which extends from the continental shelf to its base.
d. The abyssal zone is the area that includes the deep ocean (below 2,000 meters).
10. How much of the Earth’s surface is covered by marine ecosystems?
Approximately 70% of the Earth’s surface is covered by marine ecosystems.
11. Which of the aquatic ecosystems is known as the “nurseries of the sea”?
The estuary is considered to be the “nurseries of the seas”.
12. What is the pH of water which is considered to be “neutral”?
The pH of water is 7 which is considered to be neutral.