珪藻化石群集および電気伝導度から推定される過去約 1,300 年間における湖山池の環境変化

DOI

書誌事項

タイトル別名
  • Last ~1,300 years environmental change at Lake Koyama-ike inferred from diatom fossil assemblages and electric conductivity analyses, Tottori Prefecture, Japan

抄録

Using a 150-cm lake bed core sample, the paleoenvironmental change during the past ~1,300 years in Lake Koyama-ike, Tottori Prefecture, western Japan, was reconstructed based on diatom fossil assemblages, electric conductivity, and radiocarbon ages. Consequently, the following points were clarified:<br> 1) During the past 1,300 years, the surface water of Lake Koyama-ike has been a freshwater environment—freshwater pond or lake—because freshwater diatom species were dominant in the entire core. In contrast, due to salinity stratification, a brackish-to-marine environment has remained immediately above the lake bed.<br> 2) The diatom fossil assemblages indicated the decrease in water salinity and depth after ~1,000 cal BP. Because a similar transition has been previously reported in studies conducted at other sites in Lake Koyama-ike, this environmental change is a common phenomenon in this lake.<br> 3) A decrease in water salinity around 1,000 cal BP indicated that the channel connecting the Japan Sea and Lake Koyama-ike was filled by the blown sand. The shallowing of the lake around the same period was probably caused due to rapid deposition of riverine sediments and relative sea-level fall, which presumably induced the sand to actively blow in the coastal area.

収録刊行物

キーワード

詳細情報 詳細情報について

  • CRID
    1390862623772024960
  • DOI
    10.60290/laguna.24.0_27
  • ISSN
    21852995
    13403834
  • 本文言語コード
    ja
  • データソース種別
    • JaLC
  • 抄録ライセンスフラグ
    使用可

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