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Environmental reconstruction of lakes and submerged paleo-karst of the croatian adriatic coast during the late quaternary ; the case of novigradsko more catchment

In effort to outline the Holocene paleo-environmental evolution of four well-defined neighbouring karst subcatchments in the Novigradsko more catchment (central part of the EAC), a multi-proxy approach (chemical analysis, particle size analysis, magnetic susceptibility, L*a*b* spectrum, C/N analysis, bulk XRD analysis) with well-defined 14C AMS radiocarbon chronology was adopted. Four long marine sediment cores (3, 5-to 6, 5 m) were sampled in the Zrmanja river mouth, Novigradsko more, Karinsko more and Modrić bay along with fourteen soil sediment cores or profiles in their respective subcatchments. Marine sediments span over the last 11.500 yr. Three marine sediment cores penetrated the marine sediment sequences and terminated in terrestrial sediments predating the Holocene sea-level rise. In the core from Novigradsko more terrestrial sediments occur after 11.440 cal. yr. BP, in Modrić bay after 10.380 cal. yr. BP, and in Karinsko more after 10.200 cal. yr. BP. The shallow and isolated Karinsko more bay shows evidence of a short-lived brakish/freshwater lake-marsh system, recognized by low Sr/Ca ratio (Dodd & Crisp, 1982), elevated Pb/Al, Mg/Al ratios, elevated C/N (Lamb et al., 2006)) and Mo concentration, and also pollen and foraminiferal assemblages. After that period typical marine sedimentation was present. The evidence of anthropogenic changes with pronounced erosion due to deforestation in the subcatchments is evident in all marine cores. It is detected as elevated magnetic susceptibility, (Maher, 2007), change in color (influx of red terra rossas visible as high a* and b*) (St Onge et al., 2007), elevated Pb (Shotyk et al., 1998), lithogenic elements, TOC, C/N (Lamb et al., 2006) and decreased carbonates.

palaeolimnological reconstruction, sea level rise, chemical analysis, particle size analysis, magnetic susceptibility, XRD

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