The seasonal mean of the optima of ammonium-nitrogen
ranged from 634 lg/L (F. acus) to 229 lg/L (Cyclotella kuetzingiana).
Four diatom species satisfied the indicator selection
criteria for ammonium as Achnanthidium minutissimum
(564 lg/L), M. varians (586 lg/L), Navicula cocconeiformis
(564 lg/L) and Nitzschia paleaeformis (615 lg/L). The seasonal
mean of the optima of reactive phosphorus ranged from 68 lg/
L (Nitzschia filiformis) to 21 lg/L (S. acus). Entomoneis alata
(67 lg/L), C. placentula (61 lg/L), Cyclotella operculata
(61 lg/L) and Epithemia sorex (60 lg/L) satisfied the indicator
selection criteria for reactive phosphorus