Holocene Paleolake Evolution of the Bribir–Ostrovica Karst Polje (Dalmatia, Croatia): A Multi-Proxy Lake Sediment Record

Karst poljes in the Dinaric karst are widely infilled with Quaternary sediments. In the Bribir–Ostrovica karst polje, these sediments were investigated using geomorphological mapping and multiproxy analysis of lake sediment cores, including grain size, mineralogical, total organic and inorganic carbon (TOC, TIC), and ostracod analyses, coupled with radiocarbon dating. A key sediment core (OSP-3) recovered a ~470 cm long sedimentary sequence dating back to 13,200 cal yr BP. The floodplain to wetland environment occurred at the Late Pleistocene to Holocene transition (ca. 12,100 cal yr BP), evident by the first appearances of ostracods and an increase in TOC. More stable lake conditions prevailed between 9600 and 7200 cal yr BP, with dominant carbonate deposition and abundant ostracods. During the Middle and Late Holocene, increased clastic input and reduced ostracod presence indicate a shallow, dynamic water body influenced by erosion and periodic flooding. Lake sedimentation was strongly controlled by local karst topography, with a maximum lake depth of ca. 6 m. The Bribir–Ostrovica paleolake represents a rare terrestrial Holocene paleoenvironmental record from the Dinaric karst of the eastern Adriatic coast and provides valuable context for interpreting the nearby Neolithic archaeological site of Krivače as a lakeside settlement.