Pollution nutrient

In another AT study, Terrado et al. [15] characterised pollution patterns in different parts of the Ebro catchment. In the upper part of the Ebro, pollution was found to be mainly in the form of heavy metals (Zn, Cu, Cr, Pb, Cd and Hg), polycyclic aromatic hydrocarbons (PAHs), hexachlorocyclohexanes (HCHs) and trichlorobenzenes (TCBs). Etrophic conditions were also found. Pollution was found to source mainly from industry and urbanisation. The central Ebro was characterised by nutrient pollution such as the accumulation of Ca, Na, Mg and K, which highlighted the importance of salinisation effects from intensive irrigation and soils with high salt content. In the lower Ebro, organic [DDTs, hexachlorobenzene (HCB) and hexachlorobutadiene (HCBu)] and heavy metal (Hg, Cd, Zn and As) contamination was found to derive mainly from industrial and agricultural activities. 

Table 10.2 A comparison between the TOD, COD and BOD of some common nutrient pollutants.

Some forms of nutrient pollution may be found under conditions where deoxygenation is not a serious problem, and this has often been observed at the site of paper mill discharges. These forms of pollution manifest themselves as a voluminous growth of filamentous bacteria and they sometimes occur as effluent quality is improving. 

Nutrient pollution has contributed to other notable disturbances in the structure of marine food webs. These include (1) bioinvasions of macroalgae and microbial mats... 

Howarth, R.W., Sharpley, A., and Walker, D. (2002) Sources of nutrient pollution to coastal waters in the United States Implications for achieving coastal water quality goals. Estuaries 25, 656-676. 

National Research Council (2000) Clean Coastal Waters Understanding and Reducing the Effects of Nutrient Pollution. National Academy Press, Washington, DC. 

Lee, K. S., Short, F. T., and Burdick, D. M. (2004). Development of a nutrient pollution indicator using the seagrass, Zostera marina, along nutrient gradients in three New England estuaries. Aquat Bot. 78, 197-216. 

Howarth R. W., Anderson D., Cloern J., Elfring C., Hopkinson C., Lapointe B., Malone T., Marcus N., McGIathery K., Sharpley A., and Walker D. (eds.) (2000) Nutrient Pollution of Coastal Rivers, Bays, and Seas. Issues in Ecology 7. Ecological Society of America, Washington, DC. (http //esa.sdsc.edu). 

The Danube River is by far the single most important contributor to the nutrient pollution of the Black Sea. 

Both fossil fuel combustion and agricultural practices contribute significantly to atmospheric fluxes of nitrogen but not phosphorus. The magnitude of the contribution of these atmospheric fluxes to coastal nutrient pollution remains uncertain, and understudied. Nonetheless, atmospheric deposition is clearly an important contributor to coastal nutrient pollution. This source... 

Howarth, R.W., Scavia, D. and Marino, R. (2003). Nutrient Pollution in Coastal Waters Priority Topics for an Integrated National Research Program for the United States, NOAA Silver Springs, MD. 

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