Chapter 8 Aquatic Ecosystems

The area of water away from shore from the surface down as far as the sunlight reaches

Open-water zone

Predict the oxygen level in a pond

Oxygen levels are high each day while the sun is shining and plants are photosynthesizing, but they can drop dramatically at night

How do oxygen levels in a pond change during a 24-hour period?

Oxygen levels are higher in the day while the sun is shining and photosynthesis is taking place. They can drop dramatically during the night.

Microscopic free-floating plant or animal-like organisms

Plankton

What organism makes up the greatest amount of living material in a pond? What percent do they represent?

Plant-like plankton and animal-like plankton. 87%

The natural process by which sediment and organic material gradually replace the water volume, ultimately resulting in the area becoming dry land

Pond succession

Predict the impact of sediment and nutrients brought in by storm runoff on the organisms in a lake or pond ecosystem

Pond succession would speed up

Describe pond succession

As a pond ages, it fills with sediment and organic material. They become smaller, shallower ponds. In time the pond will become a wetland, then it fills even more, a meadow

What are the similarities of land plants and aquatic plants?

Both need sunlight, carbon dioxide and nutrients

Aquatic animals that feeds by filtering tiny organisms or fine particles of organic matter from water that passes through it

Filter-feeders

The area away from shore where sunlight does not reach and oxygen levels are low

Deep-water zone

A lake has most of it life:

In a ring around the shoreline, reaching out as far as it can survive

Plants living in lakes and ponds:

Include tiny, free-floating species of algae and are the food base of the ecosystem; Have wavy or slimy coatings that protect them from drying out when the water levels drop, and porous stems or leaves that let them absorb minerals right from the water

Which of the following is important to slowing pond succession and keeping a pond healthy?

Keeping a 100-foot-wide buffer of thick plant growth around the pond; Stopping excess erosion; Stopping runoff loaded with fertilizers, pesticides or other pollutants

How are ponds and lakes alike? How are they different?

Lakes are bigger than ponds. Dissolved oxygen in a lake stays pretty consistent over 24-hour period. Wind can cause waves on a lake. The ecology of the shoreline are similar. They are both standing water.