With reference to ecological succession,consider the following stateme...
- The gradual and fairly predictable change in the species composition of a given area is called ecological succession. Hence statement 1 is not correct.
- During succession, some species colonize an area and their population becomes more numerous whereas populations of other species decline and even disappear. The entire sequence of communities that successively change in a given area is called sere(s). The individual transitional communities are termed seral stages or seral communities.
- Ecological succession takes place in two kinds i.e. Primary Succession and Secondary succession.
- Primary succession occurs in essentially lifeless areas and regions (created or exposed for the first time) in which the soil is incapable of sustaining life as a result of such factors as lava flows, newly formed sand dunes, or rocks left from a retreating glacier. The species that invade a bare area are called pioneer species. The pioneer species in secondary succession are plants such as grasses, birch trees, and fireweed. The first organisms to appear in areas of primary succession are often mosses or lichens. These organisms are known as pioneer species because they are the first species present. Hence statement 2 is correct.
- Secondary succession occurs in areas where a community that previously existed has been removed; it is typified by smaller-scale disturbances that do not eliminate all life and nutrients from the environment.
- All succession whether taking place in water or on land, proceeds to a similar climax community the mesic.
- Hydrarch succession and xerarch succession are the successions of plants. Hydrarch succession takes place in wet areas and the successional series progress from hydric to the mesic conditions. As against this, xerarch succession takes place in dry areas, and the series progress from xeric to mesic conditions. Hence, both hydrarch and xerarch successions lead to medium water conditions (mesic) neither too dry (xeric) nor too wet (hydric). •
- At any time during primary or secondary succession, natural or human-induced disturbances (fire, deforestation, etc.), can convert a particular seral stage of succession to an earlier stage. Also, such disturbances create new conditions that encourage some species and discourage or eliminate other species
With reference to ecological succession,consider the following stateme...
Explanation:
Primary succession is the process of ecological succession that takes place in areas that are newly exposed and essentially lifeless. During primary succession, life gradually colonizes these barren areas, starting with pioneer species such as lichens and mosses, which can survive under harsh conditions. Over time, these pioneer species help create soil through their decomposition, allowing more complex plant and animal species to establish themselves.
Key Points:
- Primary succession occurs in areas such as bare rock, sand dunes, or volcanic lava flows where no life previously existed.
- Pioneer species play a crucial role in initiating primary succession by breaking down rock and organic matter to form soil.
- As the soil develops and more plant species colonize the area, the ecosystem becomes more diverse and complex.
- Eventually, a stable community of plants, animals, and microorganisms is established, marking the end of primary succession and the beginning of a mature ecosystem.
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