Holocene paleoclimate change in the area around Elephant Island, Antarctica: evidence from the diatom record

Abstract

A total of 84 species and varieties belonging to 37 genera are identified from the Core GC03-C1 in the Elephant Island, Antarctic Peninsula. High number of diatom valves per gram of dry sediment was observed in core, ranging from 0.2 ~ 17×107/g. The Holocene diatom assemblages from the core are dominated by Fragilariopsis kerguelensis and Eucampia antarctica which are about 47.7% of the total. The reworked diatoms inculde taxa such as Actinocyclus ingens, Rhizosolenia curvirostris, Denticulopsis praedimorpha, and D. dimorpha. Holocene paleoenvironmental history in the Elephant Islands was reconstructed through the diatom assemblage analysis from sediment core GC03-C1. Four diatom zones are identified on the basis of frequency of the critical taxa throughout the section: diatom assemblage zone I from 880 to 312 cm (late Pleistocene including Last Glacial Maximum), diatom assemblage zone II from 312 to 232 cm (transition zone), diatom assemblage zone III from 232 to 92 cm (mid-Holocene climatic optimum), and diatom assemblage zone IV from 92 to 0 cm (Neoglacial).