Factors of water quality degradation in shallow Pannonian lakes and their contribution to ecological risk.

Jezera predstavljaju prirodna staništa za divlje životinje, floru i faunu, često i za mnoge ugrožene vrste, i imaju značajnu ulogu za čovečanstvo kao izvor vode za piće, u poljoprivredi za navodnjavanje, zatim za ribarstvo, edukaciju, turizam, itd. Plitka polimiktična jezera su rasprostranjena u mnogim regionima, čak više od dubokih jezera, i od velike su važnosti posebno u gusto naseljenim područjima. Danas je eutrofikacija kritičan problem koji narušava kvalitet površinskih voda (posebno u jezerima i akumulacijama). Antropogena ili veštačka eutrofikacija (prekomeren rast i razmnožavanje biljaka koji su posledica ljudskih aktivnosti) je primarni problem sa kojim se danas suočava mnogo površinskih voda. Antropogena eutrofikacija je posledica i fekalnog zagađenja, pa se često paralelno pojavljuje i problem nezadovoljavajućeg kvaliteta vode sa sanitarnog aspekta. Obezbeđenje nutrijentima može direktno ili indirektno da ograniči metaboličke aktivnosti heterotrofnih mikroorganizama. Eutrofikacija može i indirektno da utiče na brojnost patogena, tako što utiče na brojnost i distribuciju njihovih domaćina i prenosilaca bolesti (vektora). Potencijalne veze između patogena i dostupnosti hranljivih materija mogu da imaju važan uticaj na sam sistem upravljanja zaštitom zdravlja u onim područjima, gde se na jezerima i morima ili okeanima regularno obavljaju sportsko rekreativne aktivnosti u ili na vodi. Na prostorima Republike Srbije je registrovan problem antropogene eutrofikacije u mnogim vodnim telima. Procena rizika predstavlja danas glavni alat koji se koristi u okviru politike očuvanja zdrave životne sredine na lokalnom, nacionalnom i međunarodnom nivou, kao sredstvo za određivanje prioriteta. Ekološki rizik se može izraziti kao verovatnoća da će se određena ekološka opasnost dogoditi, korišćenjem metoda koje je kvantifikuju u određenom vremenskom periodu...Lakes are a natural habitat for wildlife, flora and fauna, often for numerous endangered species, and have an important role for humanity as sources of drinking water, irrigation, fishery, education, tourism, etc. Shallow polymictic lakes are more widely spread in many regions in comparison to deep lakes and are of great importance, especially in densely populated areas. Eutrophication is a critical problem that deteriorates surface water quality (especially in lakes and reservoirs). Cultural eutrophication (excessive plant growth resulting from nutrient enrichment by human activity) is the primary problem facing most surface waters today. Cultural eutrophication is also a consequence of faecal pollution, so the sanitary water quality is usually affected as well. The abundance of nutrients may directly or indirectly limit metabolic processes of heterotrophic microorganisms. Eutrophication may indirectly influence the abundance of pathogens, through the influence on the quantity and distribution of the hosts and vectors. The potential relations between pathogens and the availability of nutrients have an important influence on the health management in areas in the vicinity of lakes, seas or oceans, where water recreational activities are regularly practiced. Cultural eutrophication is registered as a problem in many water bodies in the Republic of Serbia. Risk assessment currently represents the main tool used in the framework of a policy of preserving a healthy environment at the local, national and international levels, as a means of prioritization. Ecological risk can be expressed as the probability of occurrence of a particular environmental hazard, using a method that quantifies the hazard in a certain period of time. Ecological risk assessment has multiple applications, not only in the analysis of effects of toxic agents, but also in defining water quality criteria, such as the recommended nutrient content..