SCIENCE
ECOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Volcanic eruptions result in a surface of hardened lava.
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Fire wipes out all organisms in an area.
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A flood occurs.
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A forest is bulldozed by humans.
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Detailed explanation-1: -Primary succession occurs after a volcanic eruption or earthquake; it involves the breakdown of rocks by lichens to create new, nutrient-rich soils. The first species to colonize an area after a major disturbance are called pioneer species; they help to form the new environment.
Detailed explanation-2: -Primary succession occurs in essentially lifeless areas 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.
Detailed explanation-3: -Secondary succession occurs in an area that had previously been inhabited but experienced a disturbance, such as a lava flow. Secondary succession occurs in environments that have been distrubed, but have some remaining soil and vegetation.
Detailed explanation-4: -Succession that begins in an area with no remnants of an older community is called primary succession. For example, in Mount Saint Helens, Washington, an erupting volcano decimated all nearby living organisms. Changes in this community will continue for centuries.