Eutrophication defining

Once the options have been clearly defined it will be necessary to carry out a cost-benefit analysis of each option. This has two main objectives. First, the overall cost of the project will need to be assessed to determine whether or not it is financially viable and, second, to ensure that those who will be required to incur expenditure are fully aware of the commitment needed. The financial benefits to users of the waters for recreation, fisheries, navigation, etc., are relatively easy to determine, but monetary valuation of the environmental benefits such as conservation and general amenity will be more difficult to define. As yet this aspect of the cost-benefit analysis has not been fully developed in the UK. Having determined a range of options and costs for eutrophication control in a particular catchment, consultation on the details of the Action plan with all those involved is needed before any plan can be implemented. 

Planktonic chlorophyll increased from the upper reaches of the main section to the meandering zone of the Ebro Depression, and sharply decreased after the large reservoirs located in the lower reaches. On the basis of the chlorophyll concentration, the river Ebro can be defined as eutrophic [15]. Plankton chlorophyll levels ranged between 10 and 17 pg/L from the headwaters to the city of Zaragoza, and then increased up to 60 pg/L in the meander plain (Fig. 2a). Suspended chlorophyll in the Ebro ranged between 10 and 30 pg/L in most of the sites... 

Hombeiger GM, Spear RC. 1980. Eutrophication in Peel Inlet, I, problem-defining behavior and a mathematical model for the phosphorus scenario. Water Res 14 29-42. 

From the temporal scale of adverse effects we come to a consideration of recovery. Recovery is the rate and extent of return of a population or community to a condition that existed before the introduction of a stressor. Because ecosystems are dynamic and even under natural conditions are constantly changing in response to changes in the physical environment (weather, natural catastrophes, etc.) or other factors, it is unrealistic to expect that a system will remain static at some level or return to exactly the same state that it was before it was disturbed. Thus the attributes of a recovered system must be carefully defined. Examples might include productivity declines in an eutrophic system, re-establishment of a species at a particular density, species recolonization of a damaged habitat, or the restoration of health of diseased organisms. 

Eutrophication is defined by Cloem (2001, p. 224) as the myriad of biogeo-chemical and ecological responses, either direct or indirect, to anthropogenic fertilization of ecosystems at the land-sea interface. As it stands today, nutrient inputs represent the largest problem in rivers and estuaries. 

Vollenweider, R.A. (1976) Advances in defining critical loading levels of phosphorus in lake eutrophication. Mem 1st. Ital. Idrobiol. 33, 53-83. 

Define eutrophication. What environmental factors affect the extent of eutrophication ... 

No generally accepted definition of eutrophication exists. For example, within the European Commission eutrophication has been defined as the enrichment of water by nutrients, especially nitrogen and/or phosphorus, causing an accelerated growth of higher... 

Within the defined areas, critical loads are calculated for all major combinations of tree species and soil types (receptors) in the case of terrestrial ecosystems, or water biota (including fish species) and water types in case of freshwater ecosystems. These combinations include the great variety of different ecosystems, the sensitivity of which to both acidification and eutrophication inputs by atmospheric pollutants differs greatly, determining the necessary reduction needs when CDs are exceeded by modern deposition levels. 

Cell counts, blooming. Bloom types are defined based on blooming species and bloom density. To each bloom type a specific EQR is assigned, ranging from 0.1 to 0.7, depending on its relation to eutrophication. 

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). 

Sometimes, critical loads for nitrogen are defined in order to avoid ecosystem disturbances due to eutrophication, as well as to avoid nitrate leakage (N-saturation) and acidification. Important factors are the initial nutrient status of the ecosystem and its ability to take up nitrogen. 

While the economic compartment is easily defined by a cost-profit relationship, the correlation with the ecological compartment is difficult because we deal with several very different aspects, such as global warming potential, and different aspects may have different importance under different situations (smog in California or eutrophication of the Caspian sea). 

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