izpis_h1_title_alt

Povezave med organsko snovjo in živim srebrom v obalnem morju in lagunah : doktorska disertacija
Koron, Neža (Author), Faganeli, Jadran (Mentor) More about this mentor... This link opens in a new window, Horvat, Milena (Thesis defence commission member)

.pdfPDF - Presentation file, Download (5,89 MB)
MD5: 20BEB7386B5FAE1877E4D3324746624F

Abstract
Raziskave so bile opravljene na več raziskovalnih postajah v Tržaškem zalivu in v lagunah Marano in Grado. Gre za okolja, v katerih vladajo različne fizikalne, kemijske in biološke razmere. Cilj doktorskega dela je bil preučiti povezave med organsko snovjo (OM) in živim srebrom (Hg) v omenjenih okoljih ter ugotoviti, kako različni okoljski dejavniki in različen izvor OM ter Hg vplivajo na morebitne povezave in njihov obseg. Tržaški zaliv je onesnažen s Hg iz rudnika Hg Idrija, laguni pa sta podvrženi vplivu dveh oblikHg iz dveh ločenih virov. En je prav tako idrijski rudnik, medtem ko je drugi nedolgo nazaj delujoča kloralkalna tovarna, locirana v zgornjem delu toka reke Aussa, ki se izliva v maranski sektor lagune. Delo se je osredotočalo na povezave med OM in Hg v vodnem stolpcu in sedimentih obeh sistemov. Izkazalo se je, da je organska snov v vodnem stolpcu Tržaškega zaliva pomemben vezalec Hg in tudi drugih kovin, povezav med njimi pa v sedimentih ni bilo mogoče zaznati. Podobno se je izkazalo tudi pri analizi vzorcev iz lagun. Razlike v povezavah med OM v vodnem stolpcu in sedimentih sopovezane z različno sestavo in strukturo OM, saj je v sedimentih večinoma mogoče najti močno rekalcitrantno OM, medtem ko je OM v vodnem stolpcu bolj biodostopna in vsebuje več funkcionalnih skupin, ki omogočajo vezavo kovin. V Tržaškem zalivu oz. celotnem severnem Jadranu občasno prihaja tudi do tvorbe makroagregatov, velikih skupkov OM. Raziskovanje mehanizmov njihove tvorbe in razgradnje ter sestave in strukture je izjemnega pomena, saj je s tem omogočentudi vpogled v dinamiko naravne OM v Tržaškem zalivu. Ob analizi netopne frakcije makroagregatov so bile zaznane visoke koncentracije nekaterihkovin, kar je kazalec vključitve mineralnih delcev v strukturo. Analiza topnega dela makroagregatov je pokazala, da ima raztopljena OM makroagregatov enake lastnosti in sposobnosti vezave Hg kot naravna OM v tem okolju. Združitev metode ultrafiltracije in uporabe radioaktivnih ali stabilnih izotopov bi v prihodnje pomembno pripomogla k še natančnejšemu poznavanju mehanizmov, ki vodijo do povezav med OM in kovinami v okolju. OM ima velik vpliv na biogeokemijsko kroženje Hg, saj je pomembna z vidika napajanja mikrobnega metabolizma, s tem pa tudi tistih mikrobov, ki vodijo pretvorbe Hg. Z izvedbo eksperimentov v okoljih, v katerih ima OM različen izvor, različen izvor ima pa tudi Hg, je bila potrjena hipoteza o pomembnosti biološke dostopnosti tako OM kot Hg pri tvorbi MeHg.

Language:Slovenian
Keywords:severni Jadran, Tržaški zaliv, Maranska laguna, Gradeška laguna, onesnaženost voda, organske snovi, živo srebro, biogeokemija, biogeokemični cikli, okoljski dejavniki, vodni stolpec, sdimenti, makroagregati, disertacije
Work type:Dissertation (m)
Tipology:2.08 - Doctoral Dissertation
Organization:BF - Biotechnical Faculty
Year:2013
Publisher:[N. Koron]
Number of pages:XI, 138, [9] str.
Place:Ljubljana
UDC:550.47(262.3-17)(043.3)
COBISS.SI-ID:775543 This link opens in a new window
Views:917
Downloads:331
Metadata:XML RDF-CHPDL DC-XML DC-RDF
 
Average score:(0 votes)
Your score:Voting is allowed only to logged in users.
:
Share:AddThis
AddThis uses cookies that require your consent. Edit consent...

Secondary language

Language:English
Title:Interaction of natural organic matter with mercury in coastal marine and lagoon environments
Abstract:
Research was conducted in various experimental stations throughout Gulf of Trieste and Grado and Marano Lagoon. Ecosystems observed are governed by different physical, chemical and biological conditions. The main aim of this research was to investigate the existence and extent of interactions between organic matter (OM) and mercury (Hg). The influences of various environmental conditions were also studied. The most important factor in our study was the effect that the origin, thus structure and composition, of OM as well as Hg has on the existence and extent of interactions. Gulf of Trieste is contaminated with Hg from Idrija mercury mine whereas Hg found in Lagoon has two origins. One is Idrija mercury mine, while the other is chloralkali plant operating until recently and situated upstream of Aussa River. Aussa River is as an Aussa-Corno river system discharged into the Lagoon. During the researchdissolved and sedimentary OM and its interactions with Hg were investigated. It turned out that dissolved OM present in water column plays animportant role as Hg and other metal complexation agent, however no conclusive evidence was found that interactions between sedimentary OM and Hg exist. Similar results were obtained also on samples from the lagoon environment. It was concluded that the absence of interactions in sediments was a consequence of OM quality, meaning that its recalcitrance does not support Hg binding in the extents as water column OM does. Water column OM is apparently more bioavailable and contains functional groups more suitable for metal binding. Macroaggregates, large aggregates of OM, are relatively regularly formed in the waters of northern Adriatic, also in waters of Gulf ofTrieste. Knowledge on mechanisms of macroaggregate formation and degradationis necessary, since it offers an invaluable insight into dynamics of natural OM as well. Analyses on macroaggregate matrix showed high metal concentrations which suggested an incorporation of inorganic particles, while the results on interstitial soluble portion of macroaggregates revealed similar to identical properties in terms of structure and metal binding capacity as natural OM. In future the combined usage of ultrafiltration and radioactive or stable isotopes could prove to be invaluable tool for identifying the mechanisms behind interactions between OM and Hg. OM is one ofthe most important actors in the biogeochemical cycle of Hg, since it servesas a fuel for microbial metabolism. It supports also the microbes responsible for transformations of Hg. The experiments performed in different environments where OM and Hg have different origins allowed us to confirm the hypothesis on importance of bioavailability of OM and Hg in the formation of MeHg.


Similar documents

Similar works from RUL:
Similar works from other Slovenian collections:

Comments

Leave comment

You have to log in to leave a comment.

Comments (0)
0 - 0 / 0
 
There are no comments!

Back