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Abstract: We present a new sea-level reconstruction for the past 1500years based on biological indicators from the Central Adriatic islands. Biogenic littoral rims built by the coralline rhodophyte Lithophyllum byssoides were found on the particularly exposed sites on the rocky coasts of the islands of Vis, Ravnik and Biševo in Croatia. The presence of thick and well-developed Lithophyllum rims, considered to be precise (±10cm) sea-level indicators, points directly to the rising sea-level environment. Biogenic rims were mapped, measured and sampled for 14C dating. The obtained results point to four phases of sea-level changes. The sea-level was near stable from around 550 till 770calAD, in the Dark Ages Cold Period (DACP), then during the Medieval Climate Anomaly (MCA) (770 till 1330calAD) the sea-level increased at a rate of 0.71mm/yr. During the Little Ice Age (LIA) (1330 till 1640calAD) it was near stable again. Later, the sea-level started to rise at a much higher rate particularly during the Current Warm Period (CWP). These data were compared with local predictions derived from a glacio-hydro-isostatic models associated with the Last Glacial cycle. If the isostatic–eustatic component is separated, this area seems to have almost stable tectonic conditions during the past 1500years. Our results show that the large algal rims most likely grew during near-stable sea-level conditions that occurred during two relatively colder periods in the past 1500years. They also reveal that well-developed (up to 1.8m wide) upper levels of algal rims were formed during ~300years of stabilisation throughout the LIA. [Copyright &y& Elsevier]

Abstract: There is a great challenge for marine ecologists to explain and map benthic marine habitats by developing new methods that identify and link environmental processes responsible for those map patterns. Methods that use single factors such as sediment type or water depth for predicting and explaining marine benthic habitats are generally inadequate when applied on a broad scale. Using a combination of factors such as near bottom velocity (tidal and wind induced), temperature and salinity fields in conjunction with sediment type and depth those habitats may be more clearly characterized. In the frame of the project “Mapping the habitats of the Republic of Croatia” (financed by the Ministry of Environmental Protection and Physical Planning of the Republic of Croatia) specific oceanographic variables (sea bottom temperature, sea bottom salinity, sea bottom currents) have to be modelled as an input parameters for neural network models developed for spatial prediction of infralittoral habitat types. The physical model used in this study is based on a three-dimensional finite element method and unstructured grid. By running the model on the high resolution finite element mesh we were able to include the main features of the very complex East Adriatic coast, representing a domain with 77 islands and many narrow channels as well as varied bathymetry. To our knowledge, this study is making the first step in gaining better knowledge and understanding of the complicated relationships of specific bottom variables (model estimates), that are playing a key role for infralittoral habitat distributions, for the whole Adriatic Sea. [Copyright &y& Elsevier]