• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to project page

1997 Fiscal Year Final Research Report Summary

Environmental changes recorded in coastal lagoon sediments-the local effects and the global phenomena-

Research Project

Project/Area Number 07309009
Research Category

Grant-in-Aid for Scientific Research (A)

Allocation TypeSingle-year Grants
Section一般
Research Field 広領域
Research InstitutionShimane University

Principal Investigator

TAKAYASU Katsumi  Shimane Univ., Research Center for Coastal Lagoon Environments, Professor, 汽水域研究センター, 教授 (00127490)

Co-Investigator(Kenkyū-buntansha) SADAKATA Noboru  Hokkaido Univ.of Education, Faculty of Education (Hakodate), Professor, 教育学部函館校, 教授 (20116594)
HIRAI Yukihiro  Ehime Univ., Faculty of Education, Assoc.Professor, 教育学部, 助教授 (30181134)
KASHIMA Kaoru  Kyushu Univ., Faculty of Science, Assoc.Professor, 理学部, 助教授 (90192533)
FUKUSAWA Hitoshi  Tokyo Metropolitan Univ., Faculty of Science, Assoc.Professor, 理学部, 助教授 (80208933)
SAMPEI Yoshikazu  Shimane Univ., Interdisciplinary Faculty of Science and Engineering, Assoc.Prof., 総合理工学部, 助教授 (00226086)
Project Period (FY) 1995 – 1997
KeywordsCoastal lagoon / Brackish-water zone / Lake deposit / Bottom topography / Environmental change / Sea-level change / Human effect in environments / High resolution stratigraphy
Research Abstract

The purpose of this research project is to make clear the environmental characteristics and the forming processes of the representative coastal lagoons by extracting the local effects and the global phenomena, and to present the fundamental data for discussing on the influences of the sea level raising and the predicting artificial change of environment. For this purpose, we carried out the collaborative works in such coastal lagoons as Saroma-ko, Abashiri-ko, Hanama-ko, Nakaumi, Shinji-ko, etc.
In Lagoon Saroma-ko facing the Sea of Okhotsk, the change in water quality caused by the artificial cutting of sand bar is clearly indicated by the change in diatom assemblages, which affected the organic matter content of the bottom sediment as well as the assemblages of benthic fauna. Dredging the bottom of River Abashiri for expanding the port area accelerated the upstreaming of high saline waters to Lake Abashiri-ko. Consequently it raised the level of halocline and expanded anoxic environment in bottom waters.
In Lagoon Hamana-ko, the opening of Imagireguchi strait, which is believed to be caused by a big earthquake in 1498, is recorded by the change of diatom assemblages in the core samples. The abnormal bottom topography in the northern area of this Lake found by echo sounding is probably related to that event. These phenomena suggest that the lagoons facing the Pacific Ocean are strongly effected by the tectonic movements as well as the eustatic sea level change.
In case of the lagoons facing the Sea of Japan, such as Lake Shinji-ko, Lake Nakaumi, etc., the change in water quality and sedimentary facies are totally controlled by the meteorological effects of heavy rains, drastic change of atmospheric pressure, and seasonal strong wind. The detection and differentiation of these effects in core samples are important subject in the discussion on the global climatic change in the past to the future.

  • Research Products

    (12 results)

All Other

All Publications (12 results)

  • [Publications] 高安 克己: "コアSJ96の概要と宍道湖の古環境変遷" LAGUNA(汽水域研究). 5(印刷中). (1998)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] 高安 克己: "中海本庄水域周辺承水路の水塊動態" LAGUNA(汽水域研究). 5(印刷中). (1998)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Sampei, Y: "Changes in accumulation rate of organic carbon during the last 8000 years in sediments of Nakaumi Lagoon,Japan" Marine Chemistry. 58. 39-50 (1997)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] 福澤 仁之: "年縞堆積物を用いた白頭山-苫小牧火山灰(B-Tm)の降下年代の推定" LAGUNA(汽水域研究). 5(印刷中). (1998)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Kashima, K.: "Paleoenvironmental Changes of Lake Hamana,a semiclosed lake at the central Japan,during the last 6000 years presumed by the diatom assemblage" Diatom. 13. 187-193 (1997)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] 平井 幸弘: "500年前の東南海地震で何が起ったか" 地理. 42(11). 116-121 (1997)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] TAKAYASU,Katsumi: "Holocene environmental change of a coastal lagoon, Shinji-ko, southwest Japan, based on the analyzes of the Core SJ96." LAGUNA. 5 (in print). (1998)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] TAKAYASU,Katsumi: "Water-mass movement in the channels around Honjo area of Lake Nakaumi, southwest Japan." LAGUNA. 5 (in print). (1998)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] SAMPEI,Yoshikazu: "Changes in accumulation rate of organic carbon during the last 8000 years in sediments of Nakaumi Lagoon, Japan." Marine Chemistry. 58. 39-50 (1997)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] FUKUSAWA,Hitoshi: "Falling age of Baegdusan-Tomakomai tephra (B-Tm) estimated by using non-glacial varves." LAGUNA. 5 (in pring). (1998)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] KASHIMA,Kaoru: "Paleoenvironmental changes of Lake Hamana, a semiclosed lake at the central Japan, during the last 6000 years presumed by the diatom assemblage." Diatom. 13. 187-193 (1997)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] HIRAI,Yukihiro: "What happened at the time of Higashi-Nankai Earthquake before 500 years?" CHIRI (Geography). 42-11. 116-121 (1997)

    • Description
      「研究成果報告書概要(欧文)」より

URL: 

Published: 1999-03-16  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi