Answers

2014-07-31T20:20:59+05:30
*The leaves or fruits in trees provide food for some organisms and thus maintain ecological balance.
*Trees provide oxygen which are required for animals for respiration.
*The roots in trees hold soil and thus prevent soil erosion.
All these maintain ecological balanceĀ 
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2014-07-31T20:21:52+05:30
The leaves or fruits in trees provide food for some organisms and thus maintain ecological balance.
Trees provide oxygen
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the trees during photosynthesis absorbs carbon-dioxide from the atmosphere released by us and other human activities like fuel burning and provide us oxygen in return. thus maintaining ecological balance