96
Gonyaulax cf. grindleyi (40 million cel~I-1) comprising 90% of the population were observed in July-August of 1980 and 1981. Such blooms
were probably related to the prolonged stable weather conditions augmented by intense dredging activity in the Salerno Harbour. The dredge
sediments deposited near the coast may have enriched surface waters
with nutrients and could have released resting cysts.
In autumn, inshore phytoplankton concentrations only slightly exceeded those recorded in open waters (Carrada et al., 1982). Chlorophyll
a values from 0.5 to 0.8 mg m- 3 ,'corresponding to 30-100 • 10 3 cellsl- 1
-3 -1
and weighted mean primary. production values of about 15 mg C m d were
measured. Inshore phytoplankton communities dominated by Emiliania
huxleyi were similar to those observed in offshore areas, with the exception of a few stations situated near the outlets of small rivers.
These stations were commonly dominated by small flagellates and diatoms.
C. The boundary regions
Major changes for physical-chemical and biological parameters defined the boundary region between inshore and offshore waters. The distance from the coast for this region varied throughout the year in relation to water circulation patterns and basin morphology.
Coastal waters in the Gulf of Naples extented approximately to the
100 m isobath in summer but extended to greater areas during the rest
of the year (Carrada, unpubl.data). Such variations were best demonstrated by the annual phytoplankton cycle for station L20 located at the
300 m isobath (Carrada et al., 1979b). Biomass values (0.3-0.9 mg Chla
-3
3
-1
m ) and abundances of 30-200 • 10 cellsl
were higher than those recorded for offshore areas, suggesting an input of diluted nutrients
from inshore waters. Phytoplankton composition, however, was similar
to that observed offshore for the greater part of the year. A peak in
abundance was observed in autumn due to the overlapping of coastal and
offshore co~~unities. Primary production (Tomas, 1981) varied from 1.4
-3 -1
to 112 mg C m d
Coastal waters in the Gulf of Salerno were generally restricted to
Gonyaulax cf. grindleyi (40 million cel~I-1) comprising 90% of the population were observed in July-August of 1980 and 1981. Such blooms
were probably related to the prolonged stable weather conditions augmented by intense dredging activity in the Salerno Harbour. The dredge
sediments deposited near the coast may have enriched surface waters
with nutrients and could have released resting cysts.
In autumn, inshore phytoplankton concentrations only slightly exceeded those recorded in open waters (Carrada et al., 1982). Chlorophyll
a values from 0.5 to 0.8 mg m- 3 ,'corresponding to 30-100 • 10 3 cellsl- 1
-3 -1
and weighted mean primary. production values of about 15 mg C m d were
measured. Inshore phytoplankton communities dominated by Emiliania
huxleyi were similar to those observed in offshore areas, with the exception of a few stations situated near the outlets of small rivers.
These stations were commonly dominated by small flagellates and diatoms.
C. The boundary regions
Major changes for physical-chemical and biological parameters defined the boundary region between inshore and offshore waters. The distance from the coast for this region varied throughout the year in relation to water circulation patterns and basin morphology.
Coastal waters in the Gulf of Naples extented approximately to the
100 m isobath in summer but extended to greater areas during the rest
of the year (Carrada, unpubl.data). Such variations were best demonstrated by the annual phytoplankton cycle for station L20 located at the
300 m isobath (Carrada et al., 1979b). Biomass values (0.3-0.9 mg Chla
-3
3
-1
m ) and abundances of 30-200 • 10 cellsl
were higher than those recorded for offshore areas, suggesting an input of diluted nutrients
from inshore waters. Phytoplankton composition, however, was similar
to that observed offshore for the greater part of the year. A peak in
abundance was observed in autumn due to the overlapping of coastal and
offshore co~~unities. Primary production (Tomas, 1981) varied from 1.4
-3 -1
to 112 mg C m d
Coastal waters in the Gulf of Salerno were generally restricted to