Kväveintag

Kväveintag refers to the process by which living organisms obtain and incorporate nitrogen from their environment. Nitrogen is an essential element for life, as it is a crucial component of amino acids, proteins, nucleic acids (DNA and RNA), and other vital molecules. Organisms cannot directly utilize the abundant atmospheric nitrogen gas (N2) for their biological processes.

The primary pathway for nitrogen acquisition for many organisms is through the consumption of other organisms that have already assimilated nitrogen. For example, animals obtain nitrogen by eating plants or other animals. Plants, in turn, absorb nitrogen from the soil in the form of inorganic ions such as nitrate (NO3-) and ammonium (NH4+).

Certain microorganisms, particularly bacteria, play a pivotal role in making nitrogen available to other life forms. Nitrogen-fixing bacteria can convert atmospheric nitrogen gas into ammonia, a process essential for replenishing the soil's nitrogen supply. This fixed nitrogen can then be utilized by plants. Other microbial processes like nitrification convert ammonia into nitrites and then nitrates, which are also readily absorbed by plants. Decomposers, also often microbes, break down organic matter, releasing nitrogen back into the soil as inorganic forms, thus completing the nitrogen cycle and facilitating further kväveintag.