INVESTIGADORES
PERILLO Gerardo Miguel E.
congresos y reuniones científicas
Título:
Particulate suspended matter concentrations in the Bahía Blanca Estuary, Argentina: implications for the development of phytoplankton blooms
Autor/es:
GUINDER, V.A.; POPOVICH, C.A.; HELBLING, E.W.; PERILLO, G.M.E.
Lugar:
Bahía Blanca
Reunión:
Congreso; ECSA 44: SCIENCE AND MANAGEMENT OF ESTUARIES AND COASTS: A TALE OF TWO HEMISPHERES; 2008
Institución organizadora:
Estuarine Coastal Science Association-Instituto Argentino de Oceanografía
Resumen:
The inner zone of the Bahía Blanca Estuary is
turbid and strongly affected by tidal energy and winds that result in a high
concentration of suspended sediment. The phytoplankton community is mostly
characterized by diatoms and had recurrent winter-early spring blooms. Sampling
of total particulate suspended matter (PSM), particulate organic matter (POM)
and light extinction coefficient (k) in the water column were fortnightly
measured, and weekly during the blooming period, in a fixed station from
January 2007 to February 2008. Phytoplankton abundance, biomass and chlorophyll
a concentrations were also measured. The POM concentrations were significantly
correlated with the phytoplankton biomass (Spearmans correlation: 0.701, p
< 0.01) and both, POM and biomass, had maximal values during winter (21.8 mg
l -1 and 393.5 µgC l -1 , respectively) and mid summer
(24.3 mg l -1 and 407.0 µgC l -1 , respectively) with
cellular abundances up to 8 x106 cells l -1 and chlorophyll a up to
24.55 µgC l -1 On the other hand, PSM concentrations and k values
were significantly correlated (Spearmans correlation = 0.731, p < 0.01) and
they showed relatively lower values during the phytoplankton maximal biomass
values. During winter, PSM and k reached minimal values (23.6 mg l -1
and 0.17 m-1, respectively), that were significantly less
(Mann-Whitney test, both p < 0.01) than their respective annual mean of 77.6
mg l -1 and 2.94 m-1. Our results suggest that the
diminution of PSM concentrations in the water column with a concomitant increase
in the penetration of solar radiation seems to be one of the factors necessary
for the phytoplankton blooms to occur.