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Abstract I’ Eutrophication, is a well known phenomenon. has long been recognized as ~eof the most threatening forms or rather consequences of pollution in fresh ater or estuaries (Hutchinson. 1973). Considering the true marine environment, lisstill presents a contentious subject (Stirn, 1988). Ecologically speaking. and Ithe broadest sense, eutrophication means a substantially increased trophic level eyondthe prevailing condition in a given ecosystem. due to unusually rich supply f nutrients in the eutrophic layer (UNEP/UNESCO/FAO, 1988). The marine manifestation of eutrophication is what in limnological systems I referred to as cultural eutrophication, or simply man-made over fertilization of quaticsystem. which can be understood as a specific form of nutrient pollution nd from the view point of catastrophic changes, it can trigger as a stress factor Pearson, 1981). I According to GESAMP definition of eutrophication, which has been ccepted by UNEP Mediterranean Action Plan, it was identified as follows: ntroductionby man, directly or indirectly. of substances or energy into the marine nvironment (including estuaries) resulting in such deleterious effects as cause iarrnto living resources, hazards to human health. hinderance to marine activities ncluding fishing, impairing of quality for use of sea-water and reduction of imenities (Stirn, 1988). Under natural conditions. eutrophication is usually induced by upwellings md river discharges (provided they are not polluted. which is rarely the case), ience the consequence is natural eutrophication. Anthropogenic (cultural or manmade) eutrophication refers to the same process. but is a consequence of pollution oy sewage and related biodegradable effluents. agricultural fertilizers and polluted umosphere: often these pollutants are combined in rivers with natural background loadSof nutrients (UNEP/UNESCO/FAO, 1988). Considering the conceptual views a natural versus anthropogenic eutrophication. ~necould logically conclude that since there is no significant difference. |