Atmospheric nitrogen has to be combined with other elements, or fixed, in order to be used by plants. lightning is one way that nitrogen is fixed. when lightning occurs, the extreme heat breaks the bonds in nitrogen molecules, allowing nitrogen to combine with oxygen and form nitrogen oxides. in what way is most of the nitrogen fixed by lightning made available for use by plants?

When nitrogen molecules that are found from lightnings dissolve in rain, forming nitrates, and are carried towards Earth, the plants can now use this as a source of energy for their photosynthetic capacity. The enormous amounts of energy produced by lightning enables the nitrogen molecules to combine with oxygen from the air forming nitrogen oxides that are water soluble and falls back to earth.

From a high concentration to a low concentration.