Microbial nitrogen metabolism c Ammonium regeneration within the euphotic zone Significance of ammonium regeneration on phytoplankton nutrition Haga, H.; Nagata, T.; Sakamoto, M. Martens, K Biology of Inland Waters Lake Kizaki: Limnology and ecology of a Japanese lake 207-215 2001 https://eurekamag.com/research/035/307/035307335.php