Question

Through the atmosphere contains 78% of molecular nitrogen , still the soil is the main source of nitrogen for plants(Give scientific reason)
Those who will give first answer I will mark it Brainliest
please fast. ​

Answer 1

Answer:

Plants can only take nitrogen in the forms of ammonia and nitrates. But the Nitrogen present in the atomosphere isn't in these forms. Therefore, the nitrogen is first changed in those forms by the process of Nitrogen Fixation. Bacteria called Rhizobium present in root modules of legume plants help in the Nitrogen Fixation.

Answer 2

Soil is the main source of nitrogen because it has nitrogen in ionic form.

• Plants can not absorb nitrogen from the atmosphere as the atmosphere has a 78% of the gaseous form of nitrogen.
• Plants require nitrogen in ionic form. The ionic form is converted by nitrogen-fixing bacteria and the process is called nitrogen fixation.
• Specialized bacteria are present in roots nodules.
• Examples of nitrogen-fixing bacteria are Rhizobium, Azospirillum etc.