Coastal waters influence

July 2006 Coastal waters influenced by Gulf Stream Surface 0.41-0.73 N2 MulhoUand et at. (submitted for publication)... 

Bode, A., and Dortch, Q. (1996). Uptake and regeneration of inorganic nitrogen in coastal waters influenced by the Mississippi River Spatial and seasonal variations. J. Plankton Res. 18, 2251—2268. 

Human activity has an enormous influence on the global cycling of nutrients, especially on the movement of nutrients to estuaries and other coastal waters. For phosphorus, global fluxes are dominated by the essentially one way flow of phosphorus carried in eroded materials and wastewater from the land to the oceans, where it is ultimately buried in ocean sediments. The size of this flux is currently estimated at 22 x 106 tons per year. Prior to increased human agricultural and industrial activity,... 

The rivers play a major role in the transfert of carbon and mineral nutrients from land to the sea and influence significantly the biogeochemical processes operating in coastal waters. Quantification of the material transport, both in the dissolved and particulate forms, has been attempted by several authors in the past (Clarke, 1924 Holeman, 1968 Garrels McKenzie, 1971 Martin et al., 1980 Meybeck, 1982 Milliman Meade, 1983). Depending on the type of sampling techniques and methods of calculations employed there are differences in the reported fluxes. A major problem in such calculations is the paucity of reliable data from some of the major rivers of the world especially of Asia (see e.g. Milliman Meade, 1983). Additionally the difficulty of obtaining representative samples from the rivers will adversely affect flux calculations. Most of the inferences drawn on the nature and transport of riverine materials rest on data collected randomly - at different points in time and space. Seasonal variations in the transport of materials are very common in some of the major world rivers, and in some cases more than 60 % of the material transport occurs within a very short period of time. Furthermore, available data are not always comparable since the analytical techniques used differ from river to river. 

River water runoff is responsible for many hydrological features of river mouths and their parts - deltas, semi-enclosed coastal water bodies and open nearshore zone. Water runoff influences water levels in deltas, delta inundation, water salinity at the mouths, etc. Water runoff depresses action of the storm surges on the deltas. River sediments load determines channel processes, sedimentation in a delta and nearshore, delta formation processes, the rate of delta progradation into the sea. 

Savage RE (1930) The influence of Phaeocystis on the migration of the herring. Fishery Invest II, XII(2) 5—13 Schaub BEM, Gieskes WWC (1991) Eutrophication of the North Sea the relation between Rhine river discharge and chlorophyll-a concentration in Dutch coastal waters. In Estuaries and coasts spatial and temporal intercomparisons. ECSA 19 Symposium. Publ. Olsen and Olsen, pp 85-90... 

The theoretical models considering the influence of (algal) viruses on the carbon cycle that exist to date are steady-state models assuming a fixed percentage of the algal population dying due to viral lysis. A bloom of Phaeocystis in, for example, temperate eutrophic coastal waters is, however, clearly not a steady-state situation. Based on the ecosystem model by Ruardij et al. (2005), we established a carbon budget for the main players... 

Veldhuis MJW, Admiraal W (1987) Influence of phosphate depletion on the growth and colony formation of Phaeocystis pouchetii. Mar Biol 95 47-54 Veldhuis MJW, Wassmann P (2005) Bloom dynamics and biological control of a high biomass HAB species in European coastal waters a Phaeocystis case study. Harmful Algae 4 805-809... 

Maximum N2O saturations were usually observed in estuaries, whereas in open coastal waters (i.e. shelf waters not influenced by freshwater) N2O saturations are close to the expected equilibrium saturation indicating that N2O is exclusively formed in estuarine systems. 

Finally, a variety of zooplankton have recently been shown to produce colored (chromophoric) DOM (CDOM), a fraction of which is fluorescent (FDOM) (Steinberg et al, 2004 Urban-Rich et al, 2004, 2006). Although the nitrogenous composition of CDOM/FDOM is little known, fluorescent humic-hke material (likely fulvic and humic acids) is produced during grazing, influencing the optical characteristics of coastal waters (Urban-Rich et al, 2006). A recent culture study shows that humic-N can be a source of N for coastal phytoplankton (See et al, 2006). 

Even in his early work, Kalle surmised that Gelbstoff was a relatively stable product of phytoplankton metabolism which was forming in seawater remote from terrestrial influence. He also observed that the intensity of the blue fluorescence emitted from UV-irradiated seawater increased with increasing salinity. He concluded that in addition to the Gelbstoff of coastal waters there was also a Gelbstoff unique to the open sea. 

Carlson, D. J. and Mayer, L. M. (1983). Relative influences of riverine and macroalgal phenolic materials on UV absorbance in temperate coastal waters. Can. J. Fish. Aquat. Sci. 40, 1258-1263. 

V.S. Kuwahara, H. Ogawa, T. Toda, T. Kikuchi, S. Taguchi (2000). Variability of bio-optical factors influencing the seasonal attenuation of ultraviolet radiation in temperate coastal waters of Japan, Photochem. Photobiol, 72,193-199. 

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