4 years ago

Palaeoceanography changes in the Okhotsk Sea during Late Pleistocene and Holocene according to diatoms

Paleontological records of six sediment cores in the Okhotsk Sea (OS) marked the regional environmental changes over the last 140 kyr on orbital time scales. The diatom assemblages and content of diatom frustules in the sediments during Marine Isotope Stage (MIS) 6–1 indicate the dramatic climatic and environmental changes in the OS. A small abundance and low diatom species diversity as well as the high percentage of near-ice species indicate the cold surface environmental condition during glacial time (MIS 6, 4, 2) with low temperatures, cold climate conditions and extended sea ice cover. The presence of extinct redeposited species in the glacial assemblages indicates a low sea level during this time. The proportion of ice species enlarged and diatom abundance reduced due to increase of the influence of the sea ice, reflecting the sharp climatic cooling of adjacent land and regional environmental deterioration. The subsequent increase in diatoms productivity at 129.8–117.0 kyr BP and 8.3–5.5 kyr BP indicates the strong climate warming accompanied by decrease of sea ice coverage and surface water stratification (mixing of surface and intermediate water) during the warmest MIS in the Okhotsk Sea. The diatom abundance and high content of the oceanic and warm-water species reflect the warm surface environmental condition during MIS 5e and 1 since 8.3 kyr due to decrease of the sea ice influence.

Publisher URL: www.sciencedirect.com/science

DOI: S1040618216313246

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.