Nitrogen fixation involves the conversion of atmospheric nitrogen into ammonia and organic derivatives, by natural means, especially such conversion, by microorganisms (nitrogen fixing bacteria) in the soil, into a form that can be assimilated by plants.
The easily accessible form by which nitrogen can be obtained by plants is nitrates, as they are very soluble in soil water and easily picked by plant root vessels
The yellow xanthophylls are the next most soluble, followed by the blue-green chlorophyll A. The least soluble pigment is the yellow green chlorophyll B. You may be wondering why plants have more than one pigment.
