BRACKISH MARSH BENTHIC MICROFAUNA AND PALEOENVIRONMENTAL CHANGES DURING THE LAST 6000 YEARS AT THE COASTAL PLAIN OF MARATHON (SE GREECE)

The present study, based mainly on the analysis of foraminifers and ostracodes, provides evidence of paleoenvironmental changes on the coastal plain of Marathon (E. Greece) during the last 6.000 yrs. Three sedimentary units -lagoonal formations - were recognized and identified as A, B and C. They range in time between before 5500BP-3500BP, 3500BP-2500BP and 2500BP-recent, respectively. The study of the brackish marsh microfauna of the Marathon plain Holocene sediments reveals the presence, during the last 5500 yrs., of three distinct biofacies in the sedimentary units already established. Alternating mesohaline - oligohaline (MO), oligohaline - fresh water (OFW) and mesohaline - oligohaline to oligohaline - fresh water (MO-OFW) biofacies in the framework of the sedimentary units indicate a general trend landward along the plain suggesting a slowing of sea-level rise probably correlated with a relevant tectonic uplift. One prominent feature of this study is the clarification of the ecological preference of the species Trichohya1us aguayoi (Bermudez, 1935), which is dominant in oligohaline conditions under an influence of fresh water input (salinity less than 15 ‰).&nbsp

Unpublished Mediterranean and Black Sea records of marine alien, cryptogenic, and neonative species

To enrich spatio-temporal information on the distribution of alien, cryptogenic, and neonative species in the Mediterranean and the Black Sea, a collective effort by 173 marine scientists was made to provide unpublished records and make them open access to the scientific community. Through this effort, we collected and harmonized a dataset of 12,649 records. It includes 247 taxa, of which 217 are Animalia, 25 Plantae and 5 Chromista, from 23 countries surrounding the Mediterranean and the Black Sea. Chordata was the most abundant taxonomic group, followed by Arthropoda, Mollusca, and Annelida. In terms of species records, Siganus luridus, Siganus rivulatus, Saurida lessepsianus, Pterois miles, Upeneus moluccensis, Charybdis (Archias) longicollis, and Caulerpa cylindracea were the most numerous. The temporal distribution of the records ranges from 1973 to 2022, with 44% of the records in 2020–2021. Lethrinus borbonicus is reported for the first time in the Mediterranean Sea, while Pomatoschistus quagga, Caulerpa cylindracea, Grateloupia turuturu, and Misophria pallida are first records for the Black Sea; Kapraunia schneideri is recorded for the second time in the Mediterranean and for the first time in Israel; Prionospio depauperata and Pseudonereis anomala are reported for the first time from the Sea of Marmara. Many first country records are also included, namely: Amathia verticillata (Montenegro), Ampithoe valida (Italy), Antithamnion amphigeneum (Greece), Clavelina oblonga (Tunisia and Slovenia), Dendostrea cf. folium (Syria), Epinephelus fasciatus (Tunisia), Ganonema farinosum (Montenegro), Macrorhynchia philippina (Tunisia), Marenzelleria neglecta (Romania), Paratapes textilis (Tunisia), and Botrylloides diegensis (Tunisia).peer-reviewe

Landscape evolution recorded in the embayment of Palamari (Skyros Island, Greece) from the beginning of the Bronze Age until recent times

The Palamari bay is located on the northeastern coast of Skyros island (Sporades islands, Aegean Sea). At the northern part of the bay a prehistoric archaeological site is dated between 2800 and 1700 Before Common Era (Early Bronze Age II–Middle Bronze Age I). Our paleoenvironmental reconstruction has combined coastal and submarine geomorphological observations with the stratigraphy of late Holocene sediments, as well as micropaleontological and palynological data of the coastal deposits and radiocarbon dating. Two beachrock formations and aeolian dunes are the main coastal landforms. Three main sedimentary units were recognized and termed A, B and C, respectively. The ostracod fauna of the lowermost sedimentary A unit indicates a shallow freshwater environment. The pollen spectrum reflects an open dry vegetation of Mediterranean type. The overlying unit B is characterized by the dominance of brackish water ostracod species. A strong human presence indicating cultivated land and grazing activities is inferred from the pollen spectra. This sequence implies a lagoon connected to, but protected from the sea, which was periodically supplied with fresh water from the surrounding springs. The uppermost sedimentary C unit represents a coastal marine environment dominated by aeolian activity and modified by fluvial processes. The presence of high percentages of the coprophilous fungi of Sordaria and Sporomiella types suggests the presence of domesticated animals, possibly herds, in the area.La baie de Palamari est située sur la côte du Nord-Est de l’île de Skyros (îles de Sporades, Mer Égée). Au nord de la baie, un emplacement archéologique préhistorique a été daté entre 2800 et 1700 av. J.-C. (Bronze Supérieur II–Bronze Moyen I). Notre reconstitution paléo environnementale combine des observations géomorphologiques côtières et sous-marines à l’analyse stratigraphique des dépôts de l’Holocène inférieur, ainsi qu’aux données micropaléontologiques et palynologiques des dépôts côtiers et des datations de la matière organique en 14C. Deux beachrocks et des dunes éoliennes représentent les principales formes côtières. Trois unités sédimentaires principales, dénommées A, B et C, ont été reconnues sur la base des caractéristiques de micromorphologie, de microfaune et des pollens. L’unité sédimentaire inférieure A, avec une faune d’ostracodes, indique un environnement d’eau douce peu profond et des pollens qui sont caractéristiques d’une végétation sèche et ouverte de type méditerranéen. L’unité fondamentale B est caractérisée par la prédominance d’espèces d’ostracodes vivant dans des eaux saumâtres. Une forte présence humaine est déduite des spectres polliniques, suggérant la coexistence de terres cultivées et de l’élevage. Cette séquence sédimentaire implique qu’une lagune était reliée à la mer mais protégée de ses influences, et qu’elle était périodiquement alimentée en eau douce par les sources environnantes. L’unité sédimentaire supérieure C consiste surtout en sédiments grossiers (des sables et des cailloux) mais bien triés, qui indiquent un environnement côtier dominé principalement par les dépôts éoliens modifiés par des processus fluviaux. Son intérêt réside dans les pourcentages élevés du type cophrolithes de Sordaria de mycètes et du type de Sporomiella, qui indiquent probablement des troupeaux d’élevage dans le secteur

Observations on Palaeogeographical Evolution of Akrotiri Salt Lake, Lemesos, Cyprus

Akrotiri Salt Lake is located 5 km west of the city of Lemesos in the southernmost part of the island of Cyprus. The evolution of the Akrotiri Salt Lake is of great scientific interest, occurring during the Holocene when eustatic and isostatic movements combined with local active tectonics and climate change developed a unique geomorphological environment. The Salt Lake today is a closed lagoon, which is depicted in Venetian maps as being connected to the sea, provides evidence of the geological setting and landscape evolution of the area. In this study, for the first time, we investigated the development of the Akrotiri Salt Lake through a series of three cores which penetrated the Holocene sediment sequence. Sedimentological and micropaleontological analyses, as well as geochronological studies were performed on the deposited sediments, identifying the complexity of the evolution of the Salt Lake and the progressive change of the area from a maritime space to an open bay and finally to a closed salt lake

Assessment of Geological Heritage Sites and Their Significance for Geotouristic Exploitation: The Case of Lefkas, Meganisi, Kefalonia and Ithaki Islands, Ionian Sea, Greece

Geological heritage or geoheritage refers to the total of geosites, i.e., areas of high geological interest in a given area. Geosites have a high potential of attracting geotourists, thus contributing to the development of the local economy. Assessing sites of geological interest can contribute to their promotion, as well as their preservation and protection. Greece’s geotectonic position in the convergent zone between the African and Eurasian plates has contributed to the existence of a considerable wealth of geosites, with the particularly active geotectonic region of the Ionian Sea characterized as a geoheritage hotspot. The purpose of this study is the selection of several such sites from the islands of Lefkas, Meganisi, Kefalonia and Ithaki and their assessment regarding their scientific, environmental, cultural, economic and aesthetic value. The most representative sites for the individual disciplines of geology (e.g., geomorphology, tectonics, stratigraphy and palaeontology) have been chosen, mapped and assessed, while indicative georoutes are proposed, which could aid the island’s geotouristic promotion to geologist and non-geologist future visitors

Palaeoenvironmental changes at the Tortonian/Messinian boundary: A deep-sea sedimentary record of the eastern Mediterranean Sea

International audienceIn the eastern Mediterranean, the island of Crete offers excellent exposures of upper Miocene marine deposits. Three detailed sections of the Tortonian/Messinian sedimentary succession were measured and sampled in three different basins (from west to east: Chania, Heraklion, and Sitia). The biostratigraphic analysis based on planktonic foraminifera yielded ages ranging from about 7.58 to 6.72 Ma. Nine bioevents were also recognised and provided good correlations between the studied sections. Rich benthic faunas (commonly occurring together with fish otoliths) have furthermore been recovered and analysed: foraminifera, mollusc (mostly bivalves), bryozoans, and ostracods. The autochthonous assemblages suggest deposition at middle-upper bathyal depths at the base and outer-inner shelf in the upper parts of the sections. The shallowing upward trend observed in all three sections is accompanied by the occurrence in a few Messinian levels of allochthonous fossils transported downslope and deposited in deep-water environments. Dysoxic episodes were moreover recorded in some beds, mostly in the Messinian. A comparison with other coeval basins and faunas indicates that similar palaeoenvironmental conditions predominated throughout the Mediterranean Sea during the late Miocene. This is consistent with the postulate of open connections (through marine corridors) between the Mediterranean and the Atlantic, presumably until late in the Messinian

Assessment of Geological Heritage Sites and Their Significance for Geotouristic Exploitation: The Case of Lefkas, Meganisi, Kefalonia and Ithaki Islands, Ionian Sea, Greece

Geological heritage or geoheritage refers to the total of geosites, i.e., areas of high geological interest in a given area. Geosites have a high potential of attracting geotourists, thus contributing to the development of the local economy. Assessing sites of geological interest can contribute to their promotion, as well as their preservation and protection. Greece’s geotectonic position in the convergent zone between the African and Eurasian plates has contributed to the existence of a considerable wealth of geosites, with the particularly active geotectonic region of the Ionian Sea characterized as a geoheritage hotspot. The purpose of this study is the selection of several such sites from the islands of Lefkas, Meganisi, Kefalonia and Ithaki and their assessment regarding their scientific, environmental, cultural, economic and aesthetic value. The most representative sites for the individual disciplines of geology (e.g., geomorphology, tectonics, stratigraphy and palaeontology) have been chosen, mapped and assessed, while indicative georoutes are proposed, which could aid the island’s geotouristic promotion to geologist and non-geologist future visitors