Anthropogenic effects on marine organisms are numerous and include the increase in quantities of toxic elements or compounds, changes in habitats, direct changes in certain species, disruption of natural nutrient cycles, etc. The intensive development of industry, infrastructure and tourism causes accumulation of substances in the water column and sediments. As a result, marine organisms are exposed to ever-higher concentrations of substances in the environment.
In the master's thesis we have determined the geochemical and isotopic characteristics of noble pen shell P. nobilis (Linne, 1758), seagrass P. oceanica (Linne, 1758), sea snail H. trunculus (Linne, 1758) and sediments. The samples were collected in the framework of bilateral cooperation between Slovenia and Croatia, in the area of the National Park Kornati. Selected sampling locations differ from each other in view of the larger, smaller and smallest possible anthropogenic impacts on marine sediments and marine organisms.
We determined the isotopic characteristics of various parts of soft tissue from noble pen shell (muscle, gills, stomach) and seagrass (root and leaves). Changes of the isotope value in the soft tissue of the noble pen shell and sea snail are the result of natural processes and do not indicate anthropogenic contamination.
With geochemical analyzes of noble pen shell, sea snail and sediments we determined the extent of anthropogenic impacts at selected sampling locations. In noble pen shell sea snail, we were particularly interested in the content of selected potentially toxic elements PTE, rare earth metals REE and platinum group elements PGE. In sediments we were interested in content of REE. The results of the geochemical analysis of noble pen shell, sea snail and sediments show anthropogenic pollution at locations Mana, Piškera and Vrulje. The concentrations in the soft tissue of noble pen shell are higher for most PTE, REE and PGE than in the soft tissue of sea snail. Compared to organisms, concentrations of REE in sediments are higher.
Using the laser ablation method, we tried to determine the variability of PTE (As, Cd, Cu, Ni, Pb, Sb, Se) and REE (La, Ce) during the growth of the organism. For this purpose we made thin section of noble pen shell from the Piškera location (P-PN1). By comparing LA-ICP-MS analyzes, we determined major anthropogenic pollution over the past 10-20 years.
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