Ecological succession is:
1. gradual and predictable
2. gradual and unpredictable
3. sudden and predictable
4. sudden and unpredictable
The entire sequence of communities that successively change in a given area are called:
1. Taxa
2. Seres
3. Pioneers
4. Climax
Ecological succession has paralleled:
1. Glaciations
2. Mass extinctions
3. Genetic drifts
4. Evolution
In which of the following instances would an ecological succession regarded as secondary?
1. Newly cooled lava
2. Bare rock
3. Newly created pond
4. Abandoned farmland
Identify the correct statements regarding ecological succession:
I: | Usually, secondary succession is faster than primary succession. |
II: | Ecological succession involves a change over time in vegetation only. |
III: | Natural or human disturbance can convert a particular seral stage of succession to an earlier stage. |
1. Only I and II
2. Only I and III
3. Only II and III
4. I, II and III
Ecological succession leads to mesic conditions in:
I: | Hydrarch succession |
II: | Xerarch succession |
1. Both I and II
2. Only I
3. Only II
4. Neither I nor II
In primary succession in water, the pioneers are normally:
1. Lichens
2. Mosses
3. Phytoplankton
4. Submerged rooted plants
Lichens are very useful pioneers in succession on a bare rock, especially because:
1. they are sensitive to environmental pollution
2. they have various modes of nutrition
3. they help in the formation of soil
4. they would prevent colonization by parasites
The correct sequence of seral stages in primary hydrarch succession [pioneer to climax] would be:
1. | Phytoplankton, Submerged plant stage, Submerged free floating plant stage, Reed swamp stage, Marsh-meadow stage, Scrub stage, Forest |
2. | Phytoplankton, Submerged free floating plant stage, Submerged plant stage, Reed swamp stage, Marsh-meadow stage, Scrub stage, Forest |
3. | Phytoplankton, Submerged plant stage, Submerged free floating plant stage, Marsh-meadow stage, Reed swamp stage, Scrub stage, Forest |
4. | Phytoplankton, Reed swamp stage, Marsh-meadow stage, Submerged plant stage, Submerged free floating plant stage, Scrub stage, Forest |
The amount of nutrients present in the soil, at any given time, is referred to as:
1. Standing state
2. Standing crop
3. Primary productivity
4. Secondary productivity