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A B S T R A C TA worldwide modeling effort has been proposed by the LOICZ (Land-Ocean Interactions in the Coastal Zone) Program to foster the acquisition of intercomparable data on land-ocean fluxes in estuaries and continental shelf ecosystems from all continental margins. As part of the South American component of this initiative, we present flux estimates of water, salt, dissolved inorganic phosphorus (DIP), dissolved inorganic nitrogen (DIN) and plankton for the estuarine system of Paranaguá Bay, southern Brazil, based on the LOICZ modeling approach and local data obtained during the 1990's. This system is strongly influenced by a seasonal meteorological cycle, represented by the rainy/summer and dry/winter periods. Semi-diurnal tides of up to the 2.7-m range are responsible for the short time-scale dynamics. The model indicated a potential water export to the adjacent coast of up to 7 x 10 6 m 3 d -1 in the dry season, and 28 x 10 6 m 3 d -1 during the rainy season. The system exhibits seasonal and spatial variations in DIP and DIN fluxes. ∆DIP amounted to +2.3 x 10 6 mol P yr -1 and ∆DIN to -2.7 x 10 6 mol N yr -1 , suggesting that net production of phosphate and consumption of inorganic nitrogen predominate throughout in the system. Fluxes and therefore export of DIN and eespecially of DIP are higher in the rainy season. Stoichiometric estimates based on the C:N:P ratios of the reacting particulate organic matter (mangrove and plankton detritus) suggest that net denitrification predominates all over the bay, with values between -24.3 and -10.6 x 10 6 mol N year -1 . Estimated seaward outflows had little effect upon the fate of the phyto-and zooplankton biomass in different sectors of the bay. This is exemplified by the low net export of algal production from the upper to the middle sectors of the estuary. R E S U M OUm esforço global de modelagem foi proposto pelo Programa LOICZ (Land-Ocean Interactions in the Coastal Zone) para promover a aquisição de dados comparáveis sobre fluxos continente-oceano em ecossistemas estuarinos e de plataforma em todos os continentes. Como parte do componente sulamericano desta iniciativa, apresentamos neste trabalho estimativas de fluxo de água, sal, fósforo inorgânico dissolvido (DIP), nitrogênio inorgânico dissolvido (DIN) e plâncton para o sistema estuarino da Baía de Paranaguá, obtidas a partir da aplicação de modelos sugeridos pelo programa LOICZ. Este sistema é fortemente influenciado por um ciclo meteorológico sazonal, representado pelos períodos chuvosos de verão e secos de inverno. As marés semidiurnas, com variação de até 2,7 m, são responsáveis pela dinâmica estuarina de curta escala temporal. Nossos resultados indicam uma exportação potencial de água para a área costeira adjacente de até 7 x 10 6 m 3 d -1 no período seco e mais de 28 x 10 6 m 3 d -1 no período chuvoso. O sistema exibe variações sazonais e espaciais nos fluxos de DIP e DIN. O ∆DIP atingiu +2.3 x 10 6 mol P ano -1 e o ∆DIN to -2.7 x 10 6 mol N ano -1 , sugerindo que a produção líquida de fosfato...

Pelagic processes and their relation to vertical flux have been studied in the Norwegian and Greenland Seas since 1986. Results of long-term sediment trap deployments and adjoining process studies are presented, and the underlying methodological and conceptional background is discussed. Recent extension of these investigations at the Barents Sea continental slope are also presented. With similar conditions of input irradiation and nutrient conditions, the Norwegian and Greenland Seas exhibit comparable mean annual rates of new and total production. Major differences can be found between these regions, however, in the hydrographic conditions constraining primary production and in the composition and seasonal development of the plankton. This is reflected in differences in the temporal patterns of vertical particle flux in relation to new production in the euphotic zone, the composition of particles exported and in different processes leading to their modification in the mid-water layers.In the Norwegian Sea heavy grazing pressure during early spring retards the accumulation of phytoplankton stocks and thus a mass sedimentation of diatoms that is often associated with spring blooms. This, in conjunction with the further seasonal development of zooplankton populations, serves to delay the annual peak in sedimentation to summer or autumn. Carbonate sedimentation in the Norwegian Sea, however, is significantly higher than in the Greenland Sea, where physical factors exert a greater control on phytoplankton development and the sedimentation of opal is of greater importance. In addition to these comparative long-term A. A n t i a • E. B a u e r f e i n d -O. H a u p t • W. K o e v e E. M a c h a d o • I. P e e k e n -R. Peinert ( [ ] ) -S. R e i t m e i e r C. T h o m s e n • M. W u n s c h • U. Zeller • B. Zeitzschel Institut for M e e r e s k u n d e , D t i s t e r n b r o o k e r W e g 20, D-24105 Kiel, G e r m a n y email: rpeinert@IFM.uni-kiel.d400.de B. yon B o d u n g e n • M. Voss Institut far Ostseeforschung, Seestrasse 15, D-18119 W a r n e m t i n d e , G e r m a n ystudies a case study has been carried out at the continental slope of the Barents Sea, where an emphasis was laid on the influence of resuspension and across-slope lateral transport with an analysis of suspended and sedimented material.

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