 Succession In Ponds
If left alone, succession will eventually cause a pond to disappear!
Nature uses plants to help fill in the pond. Ponds are classified as new, young, or mature, based on the plants found.
Based on the visible plants, classify these two ponds as new, young, or mature.
Certain plants live in certain "zones" of a pond.
Plants generally appear in a pond in this order:
- Algae are the first "green things" to grow in a pond. (new pond)
- Floating plants are usually the first true plants to appear. They have no attachment to the bottom. Examples include water-hyacinth and duckweeds. (young pond)
- Submerged plants are next to appear. They are rooted in the bottom and their leaves do not extend above the surface. (middle-young pond)
- Floating plants that are rooted to the bottom are next. These are the water lilies. (mature pond)
- Emergent plants are usually the last to appear. They are rooted to the bottom and their stems and leaves extend above the surface. Examples include cattails, rushes, and sedges. (mature pond)
Over time, these plant communities accumulate organic debris and silt. Because it is shallower, the edges fill in first and the edge of the pond moves toward the center. The pond is eventually filled in and plant communities undergo "land" succession.
Remember - moss is a land plant and does not grow in ponds.
The drawing above represents a mature pond. Notice all types of plants are found.
Dead plant material will fill the edges of the pond, making it smaller and smaller.
Each group of plants has successively more mass, which helps to fill in the pond quicker as they die. The portions of emerging plants above water also help to trap dirt, causing the pond to fill even faster. You will be able to see rings in the ground surrounding an old pond where the edge of the pond used to be.
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