It appears that the phytoplankton
community, Chl a and Secchi depth are
suitable metrics for a young sub-tropical
reservoir monitoring as NT2. They illustrated
a seasonality defined by four well
distinguishable periods: (i) a phase
where the water is clear observed during
the CD season, (ii) a stable stratification
period with green algae development
involving shallow Secchi depth
during the WD season, (iii) a decrease
of the phytoplankton metrics at the top
ofWWseason and (iv) a diatoms development
at the end of the WW season.
Thanks to the knowledge of these distinct
periods, we can manage to find the
appropriate sampling frequency selecting
the number of samplings per year.
Like for European and North American
lakes and reservoirs, three campaigns
during phytoplankton production period
are recognized to get a representative
vision of trophic reservoir status. To
assess NT2 reservoir trophic state
evolution, it is then recommended to
focus on the period between the WD
and WW seasons for the NT2 trophic
assessment.