SPATIOTEMPORAL VARIABILITY OF THE THERMOHALINE AND BIOGEOCHEMICAL PROPERTIES AND DISSOLVED ORGANIC-CARBON IN A COASTAL EMBAYMENT AFFECTED BY UPWELLING - THE RIA-DE-VIGO (NW SPAIN)
Md. Doval et al., SPATIOTEMPORAL VARIABILITY OF THE THERMOHALINE AND BIOGEOCHEMICAL PROPERTIES AND DISSOLVED ORGANIC-CARBON IN A COASTAL EMBAYMENT AFFECTED BY UPWELLING - THE RIA-DE-VIGO (NW SPAIN), Journal of marine systems, 14(1-2), 1998, pp. 135-150
Hydrographic sampling was carried out along the main axis of the Ria d
e Vigo, from May 1994 to September 1995, to observe the spatio-tempora
l evolution of hydrographic and biogeochemical properties of the water
column. Meteorology controls mainly the hydrography and biogeochemist
ry of the Ria. Two periods can be distinguished on a seasonal time-sca
le: the upwelling season. from March to October and the non-upwelling
season, from November to February. A strong coupling was observed betw
een meteorological, hydrographic and biogeocbemical processes. The Ria
behaves like an extension of the shelf during the upwelling season an
d like a partially mixed estuary during the non-upwelling season. Diss
olved organic carbon was related to the thermohaline properties in the
whole water column, and with oxygen and chlorophyll a in the surface
layer. Extreme values were recorded during the upwelling season: the h
ighest values (> 100 mu M), in the surface layer during upwelling rela
xations and the lowest values (< 70 mu M), in the bottom layer in upwe
lled waters. Dissolved organic carbon maxima decrease shelfward thus s
uggesting export of dissolved organic carbon, in addition to particula
te organic carbon, from the Ria to the shelf. (C) 1998 Elsevier Scienc
e B.V.