Atmospheric nitrogen is converted to soil nitrogen for plant use by

Explanation

Nitrogen is an essential nutrient for plants, but it's not available in its most common form, atmospheric nitrogen. The nitrogen in the air is inert, so plants and animals can't use it directly. To be used by plants, the N\(_2\) must be transformed through a process called nitrogen fixation. Fixation converts nitrogen in the atmosphere into forms that plants can absorb through their root systems. Nitrogen fixation can occur through biological, lightning, or industrial processes.

Putrefaction is the biological process of organic matter breaking down, resulting in a foul smell and taste.It can also refer to the decomposition of organic waste, such as solid wastes from leather industries.

In biology, combustion can refer to the process of organic materials generating heat through bacterial composting. 

Nitrogen fixation is the process of converting atmospheric nitrogen N\(_2\) into a form that plants can use. Also, nitrification converts ammonia into nitrates used by plants. 

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