Use the passage and the illustrations to directly answer questions 1-5 on the other side. Then you will apply the information to other successions in-order to answer questions 6-10.
The water level of Lake Michigan was once 18 meters higher than it is today. As the water level fell, land was exposed. Many small lakes or ponds were left behind where there were depressions in the land. Below are illustrations and descriptions of four ponds as they exist today.
Pond A: Cattails, bulrushes, and water lilies grow in the pond. These plants have their roots in the bottom of the pond, but they can reach above the surface of the water. This pond is an ideal habitat for the animals that must climb to the surface for oxygen. Aquatic insect larvae (food for larger insects, which in turn are food for crayfish, frogs, salamanders, and turtles) are abundant.
Pond B: Plankton growth is rich enough to support animals that entered when the pond was connected to the lake. Fish make nests on the sandy bottom. Mussels crawl over the bottom.
Pond C: Decayed bodies of plants and animals form a layer of humus over the bottom of the pond. Chara, branching green algae, covers the humus. Fish that build nests on the bare bottom have been replaced by those that lay their eggs on the Chara.
Pond D: The pond is so filled with vegetation that there are no longer any large areas of open water. Instead, the pond is filled with grasses. The water dries up during the summer months.
Questions:
Succession 1 – Drying of a Pond
1. Write the letters of the ponds in order from the youngest, to the oldest.
2. As the ponds undergo succession, what is happening to the type and number of organisms?
3. Black bass and bluegill make their nests on sandy bottoms. In which pond would you find them?
4. What will happen to the black bass and blue gill as the floor of the ponds fills with organic debris?