absence of light for all tested temperatures (results presented in
Fig. 6 for 25 C; data are not shown for 5 C and 15 C). Under these
conditions, no microalgal growth was observed and consequently
the pH remained constant at around 8.5 (data not shown).
Martinez et al. [27] also reported the strong influence of pH on
ammonium removal by ammonia desorption in anoxic batch
cultures for the treatment of urban wastewater at different
temperatures. In our experiments the loss of nitrogen was mainly
attributed to this stripping phenomenon. In conclusion, high
nitrogen removals portions (72–83%), linked to biomass assimila-
tion and stripping, are observed for the different temperatures and
photoperiods tested.