NEET BIOLOGY

Detailed explanation-1: -The clearing of a rain forest is the example of a(n) human caused disaster drastic enough to prevent the original climax community from reforming. During primary succession, chance plays a large role in determining which pioneer species arrives in an area first.

Detailed explanation-2: -Pioneer communities help enrich the soil. As generations of the mosses or lichens die, their remains decompose and are added to the soil. The soil is then able to support a greater variety of plant life.

Detailed explanation-3: -In primary succession pioneer species like lichen, algae and fungi as well as abiotic factors like wind and water start to “normalise” the habitat or in other words start to develop soil and other important mechanisms for greater diversity to flourish.

Detailed explanation-4: -Lava-sterilized landscapes, newly formed sand dunes, and rocks either deposited or scoured by retreating glaciers are examples of settings in which primary succession often occurs, because these places either lack soil or their soil cannot sustain life.

Detailed explanation-5: -The first species to colonize an area after a major disturbance are called pioneer species; they help to form the new environment. Secondary succession occurs after a disturbance such as a forest fire, where there is still some organic matter to allow new plants to grow.