Why is soil very fertile in areas where there is lightning and thunder?

Answer 1

Not really. A lightning strike only superheats the soil in the area of penetration (and can form a fulgurite). From there, the charges "equalize out" by moving in all directions away from there. Certainly there will be some chemical action in the vicinity of "ground zero" for the bolt, but the chemical action is just about exactly what you'd expect you'd get buy digging up a big shovel full of the dirt from there and sticking it in a furnace for half an hour. Lightning's effect on the ground can usually be detected after a strike, but an increase in the fertility of the soil isn't an effect of the passage of many amps of current through the dirt.

Answer 2

The presence of Nitrogen in the soil increases the soil's fertility.

Atmospheric N2 is not absorbed directly into the soil. The enormous energy of lightning breaks nitrogen molecules and enables their atoms to combine with oxygen in the air forming nitrogen oxides. These dissolve in rain, forming nitrates, that are carried to the soil.

This is called nitrogen fixation. Hence, areas where there is lightning have more nitrogen in their soil and are thus, more fertile.

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Answer 3

Lightning helps fix nitrogen in the soil, making it more available to plants. Thunderstorms also help aerate the soil by increasing water infiltration and breaking up soil particles, which can improve soil structure and fertility. Additionally, lightning can release minerals from rocks, adding nutrients to the soil.