Determination of ammonia nitrogen in natural waters: Recent advances and applications

Ammonia nitrogen, consisting of un-ionized ammonia and ammonium, is a key parameter for studying the nitrogen cycle and indicating water quality. The measurement of these parameter concentrations is vital for the adequate monitoring of aquatic environments. Here, we review studies that focus on analytical methods for determining ammonia nitrogen in natural waters that were published between 2014 to mid-2019. These methods include spectrophotometric, fluorometric and electrochemical methods, and the features of these different analytical methods are reviewed. In addition, the outlook for future development is discussed.