Question

1. why are lichens successful pioneers?
2. compare and contrast primary succession and secondary succession.
3. what is the difference between primary and secondary aquatic succession?
4. summarize the sequence of events that occur when a pond undergoes secondary succession.

Explanation:

1. Lichens are successful pioneers because they can grow on bare rock. They secrete acids that break down rock, starting soil - formation. They are also able to tolerate harsh environmental conditions like extreme temperatures and low moisture.
2. Primary succession occurs in areas with no soil, like newly formed volcanic islands or areas exposed by retreating glaciers. It starts from scratch with pioneer species like lichens. Secondary succession occurs in areas where soil is already present, after a disturbance like a fire or flood. It has a faster - growing community as there is already soil and some remaining seeds or plant parts.
3. Primary aquatic succession starts in a newly formed water body with no organic matter or plants. Algae and phytoplankton are the first colonizers. Secondary aquatic succession occurs in an existing water body after a disturbance. There is already some organic matter and plant/animal remains, and the succession process is quicker.
4. When a pond undergoes secondary succession, first, plants like water lilies and cattails may grow along the edges if there is a disturbance that has opened up space. Then, as organic matter accumulates from dead plants and animals, the pond may become shallower. Eventually, emergent plants may take over more of the pond area, and over time, the pond may turn into a wet meadow or a marsh.

Answer:

1. Lichens can grow on bare rock, secrete rock - breaking acids, and tolerate harsh conditions.
2. Primary succession starts on no - soil areas with pioneer species; secondary succession on soil - present areas after disturbance.
3. Primary aquatic succession in new water bodies with initial colonizers; secondary in existing ones after disturbance with quicker process.
4. Plants grow along edges, organic matter accumulates, pond shallows, emergent plants take over, may turn to wet meadow/marsh.