What is a major result of denitrification?

Denitrification is a crucial biological process in the nitrogen cycle where nitrogen compounds in the soil are converted into nitrogen gas (N₂), which is then released into the atmosphere. This process is facilitated by certain microorganisms that utilize nitrate as an alternative electron acceptor under anaerobic conditions.

The release of nitrogen gas is significant because it helps maintain the balance of nitrogen in the environment. By removing excess nitrates from the soil, denitrification is essential in preventing problems such as water pollution and eutrophication in aquatic systems, where excess nitrogen can lead to the overgrowth of algae and depletion of oxygen in water bodies.

In contrast, other options do not accurately describe the primary outcome of denitrification. For instance, increasing soil fertility relates more to nitrate's presence rather than its conversion back to atmospheric nitrogen. The conversion of gas into nitrate is not a function of denitrification but rather involves processes such as nitrogen fixation. Lastly, reduction in atmospheric pressure is unrelated to the biological processes associated with denitrification. Therefore, the release of nitrogen gas into the atmosphere captures the essence of denitrification and its environmental importance.