Eutrophication process

Vidal A, Om J (1993) The eutrophication process in Sau reservoir (NE Spain) A longterm study. Ver Intemat Verein Limnol 25 1247-1256... 

Hazard accounting considers the total system of which the acidification influence is a part and sets practical boundaries for the assessment. For example, Figure 2 shows the acidification and eutrophication processes identification in both terrestrial and aquatic ecosystems of concern in any of its critical points. These two steps are the basis for writing TOR for the ERA to be performed. 

The ecosystem acidification and critical load calculation processes are only partly scientific exercises, being connected closely with economic development of all countries. So, in different projects the hazards of concern include ecosystem damage due to acidification and eutrophication processes (e.g., decreased productivity and biodiversity, soil erosion, drinking water quality, reproduction losses, etc.), firstly, in local scale and, secondly, in regional scale that may lead to transboundary pollution. For more details see Figure 2. 

Eutrophication Processes in Coastal Systems Origin and Succession of Plankton Blooms and Effects on Secondary Production in Gulf Coast Estuaries, Robert J. Livingston Handbook of Marine Mineral Deposits, David S. Cronan Handbook for Restoring Tidal Wetlands, Joy B. Zedler Intertidal Deposits River Mouths, Tidal Flats, and Coastal Lagoons, Doeke Eisma... 

Lapointe, B.E., and Matzie, W.R. (1996) Effects of stormwater nutrient discharges on eutrophication processes in nearshore waters of the Florida Keys. Estuaries 19, 422-435. 

It is possible that eutrophication processes and such adverse events as algal blooms and hypoxia will be more frequent in some sea areas in the future. Conditions like that can take place in the northwestern part of the Black Sea in the vicinity of the mouths of the Danube, Dnieper and Southern Bug rivers and in the Taganrogskiy Bay of the Sea of Azov. 

The nutrient distribution in the deepwaters of the central basins of the Baltic Sea is mainly determined by inflow events and stagnation periods characterized by strong variations in oxygen conditions. The general behavior of inorganic phosphorus and nitrogen compounds in the deep basins below the halocline and their reaction to Major Baltic Inflows (MBIs) is described in Chapter 10.6.2. In this chapter, the interaction between nutrients accumulated below the halocline and their influence on the surface layer and thus on eutrophication processes is studied in more detail. 

Dahlgren, S., Kautsky, L., 2001. Patterns and changes in benthic vegetation in the Baltic Sea area linked to eutrophication processes. Dept. of Bot., Stockholm University MARE, Report, Stockholm. 

This includes soil, vegetation, water (surface and ground), geology, land use etc data, influencing acidification and eutrophication processes in the considered ecosystem. 

For instance, agricultural works have lead to the following of a large part of the old Dobrogea steppe, which has increased the erosion process. To this, the administration of chemical fertilizers was added, which, washed down by the rain from the slopes, has led to the silting of the aquatic basins, plus an intensification of the anthropic eutrophication process of the respective basin. Such a situation can be seen in the cases of the Razim and Tasaul Lakes. 

Another form of alteration of the aquatic basins is represented by the establishment of the pisciculture system, which besides the creation of dames and the pardoning of the lakes, has resulted in the so-called fattening of the basin. This process consists in throwing into the water substantial quantities of manure or nutrients. This is how man with a view to increasing the fish production deliberately accelerates the eutrophication process. Such a situation can be seen at the Tatlageac Lake. 

Describe the causes which enhance the development of eutrophication process in surface waters. Compare the contributions from agriculture and industry. 

In Lake Okeechobee, Elorida, Reddy and Eisher (1991) estimated that under normal wind events, the resuspension flux of soluble phosphorus can account for approximately 6-18 times the diffusive flux. In comparison, resuspension of loosely bound, organically rich sediments into the water column was found not to be a major factor for delaying the recovery of shallow Danish lakes (Jeppesen et al., 2003). However, the resuspension of nutrient-enriched benthic sediments (accumulated during eutrophication process) along with the diffusive flux can result in the release of nutrients supporting phytoplankton productivity and delay the overall recovery process. 

In what follows we briefly describe the main characteristics of a deterministic and a stochastic model of the eutrophication process in Lake Balaton, using the concepts of formal reaction kinetics. 

In general the method of confidence intervals (Zacks, 1971, Ch. 10) may be suggested for approaching a problem of this kind. As it follows from the nature of the stochastic model, an increase in input load of phosphorus does not necessarily lead to an acceleration of the eutrophication process. The same input load, however, may lead to a major increase in algae biomass (as was probably the case in 1982). 

Much of the interest in determining phosphorus in waters stems from its crucial role in the eutrophication process, or in monitoring wastewaters, which may contribute to this process. Table 8.3 shows indicative P concentration ranges for waters of various trophic classifications [153]. What is obvious is that the analytical techniques used to determine phosphorus in even eutrophic waters must be quite sensitive. In pristine waters, very low concentrations are observed, e.g., 1 xg P L (3.2 nM) or less of FRP [154], and it is generally only in polluted waters and wastewaters that concentrations in the mg L range are... 

Sharp continental climate of Central Siberia, basin geology and vegetation define hydrological conditions of river flow. So, river flow rate and flow velocity differ significantly in various hydrological stages. All factors define regional features of eutrophication processes. 

Space and time grid is used the same as for basic system equations (2) - (8). We used literature values for the transformation rates of nitrogen and phosphorus in this stage of our research [6]. These rates include also temperature influence on eutrophication processes. 

---