Why does land become more fertile after a thunderstorm

Why does land become more fertile after a thunderstorm  

A plant accumulates nutrients from the soil as it grows. Such accumulation depletes the amount of nutrient remaining in the soil so, harvesting an arable crop, such as maize, barley or com, removes nutrients from the field. A farmer needs to replenish the nutrients continually if the land is not to become exhausted after a few seasons. 

In the context here, nutrients principally comprise compounds of nitrogen, most of which come from bacteria that employ naturally occurring catalysts (enzymes) which feed on elemental nitrogen - a process known as facing. An example is the bacterium Rhizobium which lives on beans and peas. The bacteria convert atmospheric nitrogen into ammonia, which is subsequently available for important biological molecules such as amino acids, proteins, vitamins and nucleic acids. 

Other than natural fixing, the principal sources of nutrients are the man-made fertilizers applied artificially by the farmer, the most common being inorganic ammonium nitrate (NH4NO3), which is unusually rich in nitrogen. 

The actual mechanism by which the N=N molecule cleaves is very complicated, and is not fully understood yet. It is nevertheless clear that much nitrogen is oxidized to form nitrous oxide, NO. This NO dissolves in the water that inevitably accompanies lightning and forms water-soluble nitrous acid HNO2, which further oxidizes during the storm to form nitric acid, HNO3. Nitric acid functions as a high-quality fertilizer. It has been estimated that a thunderstorm can yield many tonnes of fertilizer per acre of land. 

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