Coastal marine ecosystems, atmospheric

Howarth, R. W. (2006). Atmospheric deposition and nitrogen pollution in coastal marine ecosystems. In Acid in the Environment Lessons Learned and Future Prospects (Visgilio, G. R. and Whitelaw, D. M., eds.). Springer, NY. pp. 97-116. 

For each of these factors, there are reasons why nitrogen limitation tends to be more prevalent in coastal marine ecosystems than in lakes. For instance, lakes receive nutrient inputs from upstream terrestrial ecosystems and from the atmosphere, while estuaries and coastal marine systems receive nntrients from these sources as well as from neighboring oceanic water masses. For estuaries such as those along the northeastern coast of the United States, the ocean-water inputs of nutrients tend to have a nitrogen phosphoms ratio well below the Redfield ratio dne to denitrification on the continental shelves (Nixon et al. 1995, 1996). Thns, given similar nntrient inputs from land, estnaries are likely to be more nitrogen limited than are lakes. 

Atmospheric Deposition and Nitrogen Pollution in Coastal Marine Ecosystems... 

The uncertainty over the contribution of atmospheric deposition as a nitrogen source to coastal marine ecosystems stems from two issues uncertainty over the magnitude of nitrogen deposition onto watersheds (particularly from dry deposition ), and uncertainty over the amount of the deposited nitrogen that is subsequently exported downstream (National Resource Council 2000 Howarth et al. 2002b). Each of these is discussed in some detail in the following sections. 

In marine ecosystems, the high copper levels measured in heavily contaminated coastal areas sometimes approach the incipient lethal concentrations for some organisms (Neff and Anderson 1977). Elevated copper concentrations in marine and estuarine environments may result from atmospheric deposition, industrial and municipal wastes, urban runoff, rivers, and shoreline erosion. Chesapeake Bay, for example, receives more than 1800 kg of copper daily from these sources (Hall et al. 1988). Copper concentrations in abiotic marine materials are generally higher near shore than... 

The atmosphere transports materials to the ocean that are both harmful to marine life and that are essential for marine biological productivity. It is now apparent that atmospheric transport and deposition of some metals, nitrogen species, and synthetic organic compounds can be a significant and in some cases dominant pathway for these substances entering both estuarine and coastal waters as well as some open ocean regions. Atmospheric input clearly must be considered in any evaluation of material fluxes to marine ecosystems. However, the uncertainties in the... 

Chinese scholars have started research into the transportation of nutrients to the ocean via the atmosphere and its influence on the marine ecosystem in recent years. There were clear seasonal variations for most of the ions, and the concentrations of major ions from mban area rainwater were apparently higher than those in remote regions. By in situ incubation experiments in the coastal Yellow Sea, the atmospheric deposition with high nitrogen and low phosphorus in the Yellow Sea area was the major nutrient resource for ph3doplankton in the mixed layer during the water stratification period in summer. 

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