Eutrophication nitrogen deposition

Excess nitrogen deposition contributes not only to acidification, but can also lead to the eutrophication of soils and surface waters. 

Paerl, H.W. (1995) Coastal eutrophication in relation to atmospheric nitrogen deposition current perspectives. Opheha 41, 237-259. 

Paerl, H. W., and WhitaU, D. R. (1999). AnthropogenicaUy-derived atmospheric nitrogen deposition, marine eutrophication and harmful algal bloom expansion Is there a hnk Ambio 28, 307—311. 

Coastal eutrophication Atmospheric deposition adds nitrogen to coastal waters Paerl et al. 2002, Howarth, this volume... 

Eutrophication Large deposits of phosphorous and nitrogen to a body of water that leads to excessive aquatic plant growth, which reduces the water s oxygen levels and capacity to support life (Theodore and Theodore 1996 Riviere 1990)... 

If only one pollutant contributes to an effect, e.g., nitrogen to eutrophication or sulfur to acidification, a unique critical load (CL) can be calculated and compared with deposition (Dep). The difference is termed the exceedance of the critical loads Ex = Dep— CL. 

In accordance with the production plans (Odisharia et al 1994), the increase of emission rate for nitrogen oxides (NO ) in the area of Bovanenkovo gas exploration in Yamal peninsula will be during 2000-2015 (Figure 7). Emission of sulfur oxide will be practically permanent and will amount to about 470,000 tons per year. These data indicate also the growth of deposition rate for acid forming and eutrophication compounds in comparison with the present period (Table 1). 

Paerl, H.W. (1997) Coastal eutrophication and harmful algal blooms Importance of atmospheric deposition and groundwater as new nitrogen and other nutrient sources. Lirnnol. Oceanogr. 42, 1154—1165. 

Jaworski, N., Howarth, R., and Hetling, L. (1997). Atmospheric deposition of nitrogen oxides onto the landscape contributes to coastal eutrophication in the Northeast United States. Environ. Sci. Technol. 31, 1995-2004. 

Paerl, H. W., MaUin, M. A., Donahue, C. A., Go, M., and Peierls, B. L. (1995). Nitrogen loading sources and eutrophication of the Neuse River estuary, NC Direct and indirect roles of atmospheric deposition. UNC Water Resources Research Institute Report No. 291. 119p. NC. State Univ., Raleigh, NC. 

Because an increased supply of nitrogen in marine waters and/or phosphorus in freshwaters is typically responsible for eutrophication, directly measuring the concentration of these nutrients can indicate trophic state. Nutrients in water are either dissolved or bound to particulates produced in situ and deposited into water bodies from groundwater, atmospheric deposition, and drainage basin runoff. To measure trophic state, nutrient concentrations are measured in samples... 

Eutrophication in a system can further decrease silica availability as it is deposited with diatoms and stored in bottom sediments, as demonstrated in the Baltic Sea. The decrease in silica availability, particularly if accompanied by increases in nitrogen, may encourage the formation of some blooms of harmful algae as competition with diatoms is decreased (NRC, 1993). For all cases where long term data sets are available on silica availability in coastal waters, a decrease in silica availability relative to nitrogen or phosphorus has been correlated with an increase in harmful algal blooms. 

Critical load of nitrogen This is normally defined with respect to eutrophication, and not to acidification. The critical load of nitrogen is the maximum deposition of nitrogen compounds that will not cause eutrophication or induce any type of nutrient imbalance in any part of the ecosystem (Table 3.8). 

The rates of precipitation deposition are mapped today and allow a comparison to be made with the results of the forest decline inquiry. To get below the critical load limit for the acid input under the present conditions of reduced input of alkaline dust, it is necessary to reduce not only the S02-emission but also the emission of NO and NHj. The reduction of the nitrogen compounds is also necessary in view of a reduction of the possible eutrophication of terrestrial ecosystems, the nitrate load of the groundwater and surface waters, as well as a reduction of the ozone load. 

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