A well defined pelagic population of the Northern krill, Meganyctiphanes norvegica was sampled annually at a specific location in the Skandinavian Kattegat, and the major biochemical components were measured. Protein and lipid were the main constituents and underwent the most pronounced seasonal changes, clearly correlated to the prevailing supply of food organisms. The amount of lipid increased to a maximum of 48 % of the dry weight towards winter, out of phase with gonad maturation, and therefore interpretable as deposition of ove .r~'intering reserves. Utilisation of stored reserves proceeds over winter, with loss of lipid, and decrease in weight but not in length.Comparison with literature data showed similarities with other krill populations from different geographical locations. The biochemical components of F.uphausia superba, the key organism of the marine Antarctic ecosystem, resembled those of M. norvegica. Special polar adaptations are not obviously expressed in the proximate biochemical composition.

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Atmospheric concentration in the marine boundary layer and direct deposition measurements of total nitrate and ammonium for an eastern South Pacific coastal site near Valparaiso, Chile, were carried out during the period January 1992 through March 1993. Concentrations in air for both nitrogen forms exhibit a seasonal pattern with low values in summer and a pronounced increase in winter, having a mean annual concentration of 32.6 nmol m '3 for total nitrate and of 44.8 nmol m '3 for total ammonium. Wet deposition is characterized by annual precipitation weighted concentrations of 6.0 and 8.1 gmol dm '• for nitrate and ammonium, respectively. The main factor regulating wet deposition for both nitrate and ammonium is rainfall amount, so that changes in precipitation amount alone originated by climatological factors can produce changes in their relative deposition levels. Existing climatological pattern determines an overall dominance of dry over wet deposition, with totals of 12.9 and 7.34 mmol 2 m' per year, the reduced forms of nitrogen being generally more abundant. Introduction Air to sea flux of nitrogen compounds plays an important role in the biogeochemical cycling of that element. Growing interest in understanding the processes involved in the transfer to the sea of both oxidized and reduced forms of nitrogen led to a number of publications addressing the questions of their atmospheric concentrations and deposition over the past decade [e.g., Ayers and Gras, 1980, 1983; Galloway et al., 1983; Galloway and Gaudry, 1984; Galloway, 1985; Knap et al., 1986; Galloway and Welpdale, 1987; Hastie et al., 1988; Prospero and Savoie, 1989; Prado-Fiedler, 1990a]. Since the works of Brimblecombe and Stedman [1982] giving evidence of a remarkable long-term increase of nitrate concentrations in rain and of Paerl [1985] showing the possibility of sigrdficant enrichment of coastal primary production derived from nitrate enriched rainwater, the impact of atmospheric deposition on new production has been considered very important and has been taken into account in new reviews on the matter [Legendre and Gosselin, 1989; Sharp, 1991]. Global estimates of the impact of atmospheric input on open ocean productivity were first given by Duce [1986]. More recent flux estimates on a globai scale have been given by Duce et al. [1991]. This last work illustrates the important fraction of total oxidized nitrogen entering the ocean by wet deposition and the marked northern/southern hemisphere contrast in fluxes. The growing significance of atmospheric nitrogen deposition in determining aiterations of primary productivity, nutrient fluxes, and trophic changes leading to coastal eutrophication on a regional scale has been recently revised by Paerl [1993]. Depending on the source strengths and the receiving environment, from 10% to more than 50% of coastal nitrogen loading can stem from wet and dry deposition aione [Prado-Fiedler, 1990a; Loye-Pilot et al., 1990; Duce, 1991; Fisher Copyright 1996 by the Angfican Geophysical Union. Paper number...

The atmospheric input of inorganic nitrogen species to the Kiel Bight (south-west Baltic Sea) is characterized. This characterization is based on marine precipitation samples collected at Kiel Lighthouse in weekly intervals during a whole year, using wet-only and bulk-sample methods. The temporal patterns of nitrate and ammonium concentrations are highly variable, with less variability during summer. Maximum concentrations were found in winter. The annual precipitation weighted mean concentrations are 124 ~mol 9 dm -3 for nitrate and 172 ~mol -dm -3 for ammonium. Nitrite concentrations were low, its contribution to wet deposition being thus negligible (on average only 0.3 % of the wet deposition of nitrate plus ammonium). Dry deposition represents approximately one third of the total input of airborne nitrogen species. Wet and dry deposition represent an annual input of around 5000 tons of nitrogen to the Kiel Bight (2571 kin2), being a significant contribution to its total nitrogen content (5900 tons in winter). The hypothesis of a triggering effect of intense nitrogen wet deposition pulses for summer phytoplankton blooms is raised and a possible relationship of phytoplankton patchiness with these deposition patterns to the sea is suggested.