Q. In the grasslands, trees do not replace the grasses as a part of an ecological succession because of
- Insects and fungi
- Limited sunlight and paucity of nutrients
- Water limits and fire
- None of the above
Answer: (c) Water limits and fire
Notes:
- The trees do not replace grasses as they require more water than grasses and this would lead to water scarcity for other species.
- Also, trees are prone to catch fire and the fire spreads swiftly. Due to these reasons, trees do not replace the grasses as a part of ecological succession.
Ecological Succession:
- When there is a change in the species structure of an ecological community over a period, it is called ecological succession.
- The process continues until a stable community is formed, which is known as the climax community.
- As the process continues the complexity of the community keeps on increasing.
- Ecological Succession is of following two types:
- Primary Succession – When the succession starts from an area that has not been previously occupied is referred to as primary succession. The pioneer species here include microorganisms, lichens, and mosses.
- Secondary Succession – When the process of succession occurs in an area where species existed at some point in time is referred to as secondary succession.
- Secondary Succession is relatively rapid, as the land contains the nutrients required for the survival of species.