Cutting down only mature trees allows more resources to be available for the younger growing trees and extends the life of the forest.
Explanation:
- Older an taller trees grow to a height and forms a canopy over the forest floor.
- This cuts the maximum amount of sunlight from reaching the under growths.
- Thus the shorter and younger trees lie in shade and cannot grow properly due to lack of sunlight.
- On the other hand the trees could penetrate deeper into the soil consuming up a lot of nutrient and the competition for resources becomes maximum.
- When taller and older trees are cut, the canopy is removed and sunlight couldl penetrate to the forest floor and the stress on soil is also reduced , thus allows the growth of younger trees which in turn extends the life of the forest.
Answer:
The correct answer is option D, that is, bottleneck effect.
Explanation:
A phenomenon, which occurs due to events like earthquakes, floods, or other natural calamities that result in the severe declination in the size of a particular population is known as the bottleneck effect. The bottleneck effect is an extreme illustration of genetic drift that results in the reduction of a population's genetic variability.
With the decline in the size of a specific population, a reduction in the genetic variability of the same population is witnessed due to the loss of alleles. This eventually makes the population vulnerable to pollution and diseases. Hence, the given case is an example of the bottleneck effect.
The correct answer is (a.) core. Mantle convection is a circulation of heat emitted by the earth's core. The Mantle convection is the creeping motion of the Earth's mantle that is causing the heat to transmit from the inferior portion of the core to the Earth's surface.