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.

中文翻译：

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天然水中氨氮的测定：最新进展和应用

氨氮由未离子化的氨和铵组成，是研究氮循环和指示水质的关键参数。这些参数浓度的测量对于充分监测水生环境至关重要。在这里，我们回顾了2014年至2019年中期发布的专注于测定天然水中氨氮的分析方法的研究。这些方法包括分光光度法，荧光法和电化学法，并对这些不同分析方法的特点进行了综述。此外，讨论了未来的发展前景。