124
J.G. Tundisi and T. Matsumura-Tundisi
rare. In open channel areas, 9-10 m high trees of Rizophora mangle are the
dominant vegetation on soft sediments. River-borne sediments in front of
mangrove vegetation are occupied by a fringe of Spartina sp. Between the
margins and the inner part of the mangrove forest with more solid substrate, a mixture of Rizophora mangle and Laguncularia racemosa is associated with Avicenia shaweriana. Basin forests are dominated by Laguncularia racemosa, which grows on sandy soils to a maximum height of 2.5 m.
Transitional vegetation from the mangrove to Tropical Atlantic forest is
common. The structural development of the mangrove forest is a function
of periodicity of inputs and nature and intensity of stress factors (Cintron
and Schaeffer-Novelli 1983). The spatial and structural variability of the
mangrove forest depends on the complex interaction between water level
fluctuations, terrestrial nutrient input, freshwater, low temperature, high
soil salinity, and drought stress (Adaime 1985).
9.3.2 Plankton Community
Phytoplankton growth and production cycles are more pronounced in inshore waters of Cananeia than in adjacent coastal waters (Teixeira and
Kutner 1963; Teixeira et al. 1965, 1969; Tundisi et al. 1973, 1978), with primary production (mainly nanoplankton <50 11m) reaching approximately
1 g C m- 2 day- 1 and 0.1 g C m- 2 day- 1 , respectively (Tundisi 1970). Diatoms,
with Skeletonema costatum as the dominant species (Kutner 1972), prevail
during peak growth and primary production in the rainy summer
(December to March), though up to 20 o/o photosynthetic inhibition at the
surface is common in inshore areas (Teixeira et al. 1969). The growth of
Skeletonema costatum (Aidar Aragao 1980), as well as that of other phytoplankton, appears to be stimulated by dissolved humic substances from
mangroves after mixing with coastal water (Tundisi 1970). A second peak
in early winter (September/October) is dominated by Cyclotella stylorum
(Kutner 1972). In general, the vertical distribution of phytoplankton and
chlorophyll a is influenced by flood tides. For example, during high tide,
bottom waters have denser populations of Chaetocera sp. and Skeletonema
costatum than surface waters (Brandini 1982). Seasonal phytoplankton
cycles and the succession of species were altered during the closing of the
Valo Grande channel (1978-1995), and Skeletonema costatum summer
blooms were absent (Kutner and Aidar Aragao 1986). The standing stock
of phytoplankton decreased and diatoms, such as Phaeodactylum tricornutum and Lauderia anulata, were common. Dinoflagellates were more frequent and coastal water species ( Ceratium furca) dominated (Kutner and
Sassi 1979). The conspicuous seasonal cycle of phytoplankton in inshore
J.G. Tundisi and T. Matsumura-Tundisi
rare. In open channel areas, 9-10 m high trees of Rizophora mangle are the
dominant vegetation on soft sediments. River-borne sediments in front of
mangrove vegetation are occupied by a fringe of Spartina sp. Between the
margins and the inner part of the mangrove forest with more solid substrate, a mixture of Rizophora mangle and Laguncularia racemosa is associated with Avicenia shaweriana. Basin forests are dominated by Laguncularia racemosa, which grows on sandy soils to a maximum height of 2.5 m.
Transitional vegetation from the mangrove to Tropical Atlantic forest is
common. The structural development of the mangrove forest is a function
of periodicity of inputs and nature and intensity of stress factors (Cintron
and Schaeffer-Novelli 1983). The spatial and structural variability of the
mangrove forest depends on the complex interaction between water level
fluctuations, terrestrial nutrient input, freshwater, low temperature, high
soil salinity, and drought stress (Adaime 1985).
9.3.2 Plankton Community
Phytoplankton growth and production cycles are more pronounced in inshore waters of Cananeia than in adjacent coastal waters (Teixeira and
Kutner 1963; Teixeira et al. 1965, 1969; Tundisi et al. 1973, 1978), with primary production (mainly nanoplankton <50 11m) reaching approximately
1 g C m- 2 day- 1 and 0.1 g C m- 2 day- 1 , respectively (Tundisi 1970). Diatoms,
with Skeletonema costatum as the dominant species (Kutner 1972), prevail
during peak growth and primary production in the rainy summer
(December to March), though up to 20 o/o photosynthetic inhibition at the
surface is common in inshore areas (Teixeira et al. 1969). The growth of
Skeletonema costatum (Aidar Aragao 1980), as well as that of other phytoplankton, appears to be stimulated by dissolved humic substances from
mangroves after mixing with coastal water (Tundisi 1970). A second peak
in early winter (September/October) is dominated by Cyclotella stylorum
(Kutner 1972). In general, the vertical distribution of phytoplankton and
chlorophyll a is influenced by flood tides. For example, during high tide,
bottom waters have denser populations of Chaetocera sp. and Skeletonema
costatum than surface waters (Brandini 1982). Seasonal phytoplankton
cycles and the succession of species were altered during the closing of the
Valo Grande channel (1978-1995), and Skeletonema costatum summer
blooms were absent (Kutner and Aidar Aragao 1986). The standing stock
of phytoplankton decreased and diatoms, such as Phaeodactylum tricornutum and Lauderia anulata, were common. Dinoflagellates were more frequent and coastal water species ( Ceratium furca) dominated (Kutner and
Sassi 1979). The conspicuous seasonal cycle of phytoplankton in inshore