| Title | Late-Holocene palaeoenvironmental changes at Lake Esmeralda (Vega Island, Antarctic Peninsula) based on a multi-proxy analysis of laminated lake sediment |
| Abstract | We have studied laminated sediments from Lake Esmeralda, Vega Island, in order to reconstruct its history. We describe both inorganic and organic components of the sediment using a combination of the following analytical methods: x-ray fluorescence (XRF), x-ray diffraction (XRD), magnetic susceptibility measurement, chemical analysis for determination of cation exchange capacity, grain size determination, geochemical analyses (total inorganic carbon (TIC), total organic carbon (TOC), total sulphur (TS)), spectrophotometry, high-pressure liquid chromatography, and diatom assemblage and faunal remains characterization. The geochronology of the core was based on modelling optically stimulated luminescence ages and supported by laminae counting. The dating results imply a maximum age of similar to 400 years for the 177-cm long core and a period covered of similar to 200 years, suggesting (quasi-)annual laminae formation. Such a young age contradicts previous findings based on radiocarbon dating. Geomorphological evidence indicates that river capture isolated the lake catchment from upslope sediment delivery, effectively terminating accumulation similar to 230 years ago. Conversely, our short-term palaeoenvironmental record yields a subdecadal temporal resolution, which is unparalleled in comparison with other Antarctic palaeolimnological studies. Our interpretations of the geochemical and mineralogical proxy data give us insight into the past lake catchment and waterbody evolution, and lead us to recognize periods of enhanced weathering, bottom anoxia and to distinguish major lake level changes. |
| Source | Holocene (Sevenoaks) 29 (7), pp. 1155–1175 |
| Keywords | Antarcticalake sedimentOSLpalaeolimnologylate-Holocene climateriver piracy |
| Journal | Holocene (Sevenoaks) |
| Editor | Sage, London, Regno Unito |
| Year | 2019 |
| Type | Articolo in rivista |
| DOI | 10.1177/0959683619838033 |
| Authors | Piskova, Anna; Roman, Matej; Bulinova, Marie; Pokorny, Matej; Sanderson, David; Cresswell, Alan; Manuel Lirio, Juan; Herminda Coria, Silvia; Nedbalova, Linda; Lami, Andrea; Musazzi, Simona; Van de Vijver, Bart; Nyvlt, Daniel; Kopalova, Katerina |
| Text | 407812 2019 10.1177/0959683619838033 ISI Web of Science WOS 000475684800005 Scopus 2 s2.0 85063935621 Antarctica lake sediment OSL palaeolimnology late Holocene climate river piracy Late Holocene palaeoenvironmental changes at Lake Esmeralda Vega Island, Antarctic Peninsula based on a multi proxy analysis of laminated lake sediment Piskova, Anna; Roman, Matej; Bulinova, Marie; Pokorny, Matej; Sanderson, David; Cresswell, Alan; Manuel Lirio, Juan; Herminda Coria, Silvia; Nedbalova, Linda; Lami, Andrea; Musazzi, Simona; Van de Vijver, Bart; Nyvlt, Daniel; Kopalova, Katerina Charles Univ Prague; Masaryk Univ; Charles Univ Prague; SUERC; Inst Antartico Argentino; Ist Studio Ecosistemi; Bot Garden Meise We have studied laminated sediments from Lake Esmeralda, Vega Island, in order to reconstruct its history. We describe both inorganic and organic components of the sediment using a combination of the following analytical methods x ray fluorescence XRF , x ray diffraction XRD , magnetic susceptibility measurement, chemical analysis for determination of cation exchange capacity, grain size determination, geochemical analyses total inorganic carbon TIC , total organic carbon TOC , total sulphur TS , spectrophotometry, high pressure liquid chromatography, and diatom assemblage and faunal remains characterization. The geochronology of the core was based on modelling optically stimulated luminescence ages and supported by laminae counting. The dating results imply a maximum age of similar to 400 years for the 177 cm long core and a period covered of similar to 200 years, suggesting quasi annual laminae formation. Such a young age contradicts previous findings based on radiocarbon dating. Geomorphological evidence indicates that river capture isolated the lake catchment from upslope sediment delivery, effectively terminating accumulation similar to 230 years ago. Conversely, our short term palaeoenvironmental record yields a subdecadal temporal resolution, which is unparalleled in comparison with other Antarctic palaeolimnological studies. Our interpretations of the geochemical and mineralogical proxy data give us insight into the past lake catchment and waterbody evolution, and lead us to recognize periods of enhanced weathering, bottom anoxia and to distinguish major lake level changes. 29 Published version http //journals.sagepub.com/doi/10.1177/0959683619838033 articolo versione pdf 0959683619838033.pdf Articolo in rivista Sage 0959 6836 Holocene Sevenoaks Holocene Sevenoaks Holocene Sevenoaks The Holocene Sevenoaks andrea.lami LAMI ANDREA simona.musazzi MUSAZZI SIMONA |
