Estuary, nutrient cycling

Nixon, S.W., 1981. Remineralization and nutrient cycling in coastal marine ecosystems, In B.3. Neilson and L.E. Cronin (eds), Estuaries and Nutrients. Humana Press, N3, pp. 111-138.. 

Ferguson, A., Eyre, B., and Gay, J. (2004) Nutrient cycling in the sub-tropical Brunswick estuary, Australia. Estuaries 27, 1-17. 

Giblin, A.E., Hopkinson, C.S., and Tucker, J. (1997) Benthic metabolism and nutrient cycling in Boston Harbor, Massachusetts. Estuaries. 20, 346-364. 

Kroeze, C., and Seitzinger, S.P. (1998) Nitrogen inputs to rivers, estuaries and continental shelves and related nitrous oxide emissions in 1990 and 2050 a global model. Nutrient Cycl. Agroecosyst. 52 195-212. 

Rizzo, W.M., Lackey, G.J., and Christian, R.R. (1992) Significance of euphotic, subtidal sediments to oxygen and nutrient cycling in a temperate estuary. Mar. Ecol. Prog. Ser. 86, 51-61. 

Howarth, R. W. (1998). An assessment of human influences on inputs of nitrogen to the estuaries and continental shelves of the North Adantic Ocean. Nutrient Cycling Agroecosyst. 52, 213—223. 

Flindt, M. R., Neto, J., Amos, C. L., Pardal, M. A., Bergamasco, A., Pedersen, C. B., and Andersen, F. 0. (2004). Plant bound nutrient transport Mass transport in estuaries and lagoons. In Estuarine Nutrient Cycling The Influence ofPrimary Producers (Nielsen, S. L., Banta, G. T., and Pedersen, M. F. eds.). Kluwer Academic Publishers, Dordrecht, pp. 93—128. 

Shuiwang, D., Shen, Z., and Hongyu, H. (2000). Transport of dissolved inorganic nitrogen from the major rivers to estuaries in China. Nutrient Cycling Agroecosyst. 57, 13—22. 

Rendell, A.R., Horrobin, T.M., Jickells, T.D, Edmunds, H.M., Brown, J. Malcolm, S.J. (in press) Nutrient cycling in the Great Ouse Estuary and its impact on nutrient fluxes to The Wash, England. Estuarine, Coastal and Shelf Science. 

These nutrients that are supplied from the seabed during summer are transported to the head of the bay by the estuarine circulation. Furthermore, they are again uptaken into the upper water, and are used for the increase in the phytoplanktons in the euphotic zone. Estuarine circulation plays a key role in the nutrient cycles of stratified estuaries by increasing the retention, recycling the nutrients, and stabilizing the ecosystem. ... 

Figure 76. Simplified schematic diagram of a nutrient cycle in an estuary. From T. W. Duke and Rice (1966).

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 majority of runoff from land to the oceans is dominated by riverine inputs, with minimal inputs directly from groundwater runoff. However, recent work has shown that SGD into estuaries and coastal waters is more significant than previously thought and may have significant impacts on the cycling of nutrients and contaminants. 

Figure 8.4 Biogeochemical cycling of nutrients, DOM, and POM, in the estuary proper bound by coastal ocean and riverine end-member exchange. (Modified from Wakeham and Lee, 1993.)...

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