Question

how physical nitrgen fixation takes place?​

Answer 1

Answer:

The other sources of available soil nitrogen may be amino acids from decaying organic matter, animal excreta (urea) and chemical fertilizers that can be absorbed directly by the plants. Nitrogen is obtained by the plants mainly from the atmosphere. It occurs as free diatomic (N2) molecules in the air.

Answer 2

Answer:

Nitrogen fixation occurs between some termites and fungi. It occurs naturally in the air by means of NOx production by lightning. All biological nitrogen fixation is effected by enzymes called nitrogenases. These enzymes contain iron, often with a second metal, usually molybdenum but sometimes vanadium.