Class 12th Biology 2016 Set1 Outside Delhi Board Paper Solution
Differentiate between primary and secondary succession. Provide one example of each.
Primary succession :
1) The invading species are either lichens (on rocks) or phyto planktons (in water).
2) Rate of succession is slow
3) Climax is slow to reach
Example: Newly cooled lava / bare rocks / newly created ponds or reservoir
Secondary succession:
1) The invading species depend on the condition of soil,availablility of water and type of seed.
2) Rate of succession is faster
3) Climax is reached faster.
Example: Abandoned farm lands / burnt or cut forests / lands that have been flooded
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