Sekundarni jezik: |
Angleški jezik |
Sekundarni naslov: |
Mercury exchange between water and air in the Gulf of Trieste |
Sekundarni povzetek: |
Mercury is found in both water and air and can be transported on long distances; therefore, it is considered as a global polutant. Due to development of industry mercury concentrations are increased in all environmental compartments. Vapors of elemental mercury are harmful to humans; however, the greatest risk represents methylated mercury, produced by bacteria in sediment. Methylmercury easily biomagnifies and bioaccumulates within the food chain. At highest risk are those people whose main food-source are fish and shellfish. Due to the awareness of mercury toxicity, researches worldwide are trying to explain mercury speciation and evaluate the factors influencing transformations and fluxes of mercury between the environmental compartments, especially in the marine environment. The largest part of fluxes in the Mediterranean Sea represents exchange between the water and air. In the Gulf of Trieste, this is a highly important term of the mass balance. Wind has been considered as the main factor influencing the exchange of mercury between the water and air,. Different models (parameterizations)
based on measurements and experiments have been developed in order to determine the wind impact on the gas exchange. In our study, the same set of input data used to compare different parametrizations resulted in up to three-fold different results. Using only comparison between the models the evaluation of the best and most suitable model was not possible. We also analyzed the effect of wind-averaging: although averaging reduces the wind peaks, the differences in the final results are small. |
Sekundarne ključne besede: |
graduation thesis;civil engineering;mercury;air-sea gas exchange;gas exchange model;gas transfer velocity;Gulf of Trieste; |
Vrsta datoteke: |
application/pdf |
Vrsta dela (COBISS): |
Diplomsko delo/naloga |
Komentar na gradivo: |
Univ. v Ljubljani, Fak. za gradbeništvo in geodezijo |
Strani: |
XIV, 38 str. |
Vrsta dela (ePrints): |
thesis |
Naslov (ePrints): |
Mercury exchange between water and air in the Gulf of Trieste |
Ključne besede (ePrints): |
živo srebro;izmenjava plina med vodo in zrakom;model izmenjave plina;hitrost prenosa plina;Tržaški zaliv |
Ključne besede (ePrints, sekundarni jezik): |
mercury;air-sea gas exchange;gas exchange model;gas transfer velocity;Gulf of Trieste |
Povzetek (ePrints): |
Živo srebro se nahaja tako v vodi kot v zraku in lahko prepotuje velike razdalje, zaradi cesar se danes obravnava kot globalno onesnažilo. Z razvojem industrije so se koncentracije živega srebra povecale v vseh okoljskih segmentih. Hlapi elementarnega živega srebra so za cloveka škodljivi, vendar najvecjo nevarnost cloveku predstavlja metilirano živo srebro, ki s pomocjo bakterij nastaja v sedimentu in se zlahka bioakumulira in biomagnificira v prehranjevalni verigi. Najbolj ogroženi so ljudje, katerih
glavni vir prehrane so ribe in školjke. Zaradi zavedanja o njegovi strupenosti se znanstveniki po celem svetu trudijo razložiti speciacijo živega srebra in ovrednotiti faktorje, ki vplivajo na pretvorbe in tokove živega srebra med razlicnimi okoljskimi segmenti, predvsem v morju. Najvecji delež tokov v Sredozemskem morju predstavlja izmenjava med vodo in zrakom. V Tržaškem zalivu je ta clen masne bilance zelo pomemben. Za glavni dejavnik, ki vpliva na izmenjavo živega srebra med vodo in zrakom, velja veter. Na podlagi meritev in poizkusov so bili razviti razlicni modeli (parametrizacije), za upoštevanje vetra v racunu izmenjave. Pri primerjavi parametrizacij smo uporabili enake vhodne
podatke, dobili pa smo zelo razlicne rezultate, razlike so lahko tudi do trikratne. S samo primerjavo med modeli je ovrednotenje najboljšega in najbolj primernega nemogoce. Preverili smo tudi vpliv povprecenja vetra in ugotovili, da s povprecenjem sicer zmanjšujemo vetrovne konice, vendar pa so razlike pri koncnih rezultatih majhne. |
Povzetek (ePrints, sekundarni jezik): |
Mercury is found in both water and air and can be transported on long distances; therefore, it is considered as a global polutant. Due to development of industry mercury concentrations are increased in all environmental compartments. Vapors of elemental mercury are harmful to humans; however, the greatest risk represents methylated mercury, produced by bacteria in sediment. Methylmercury easily biomagnifies and bioaccumulates within the food chain. At highest risk are those people whose main food-source are fish and shellfish. Due to the awareness of mercury toxicity, researches worldwide are trying to explain mercury speciation and evaluate the factors influencing transformations and fluxes of mercury between the environmental compartments, especially in the marine environment. The largest part of fluxes in the Mediterranean Sea represents exchange between the water and air. In the Gulf of Trieste, this is a highly important term of the mass balance. Wind has been considered as the main factor influencing the exchange of mercury between the water and air,. Different models (parameterizations)
based on measurements and experiments have been developed in order to determine the wind impact on the gas exchange. In our study, the same set of input data used to compare different parametrizations resulted in up to three-fold different results. Using only comparison between the models the evaluation of the best and most suitable model was not possible. We also analyzed the effect of wind-averaging: although averaging reduces the wind peaks, the differences in the final results are small. |
Ključne besede (ePrints, sekundarni jezik): |
mercury;air-sea gas exchange;gas exchange model;gas transfer velocity;Gulf of Trieste |
ID: |
8312907 |