Updated on 2024/10/08

写真a

 
YAMADA, Kazuyoshi
 
Affiliation
Faculty of Human Sciences, School of Human Sciences
Job title
Professor
Degree
Doctor of Science ( 2002.03 Tokyo Metropolitan University )

Research Experience

  • 2020.04
    -
    Now

    Waseda University   Faculty of Human Sciences

  • 2020.04
    -
    Now

    ふじのくに地球環境史ミュージアム   客員教授

  • 2017.04
    -
    Now

    Shizuoka University   Center for Integrated Research and Education of Natural Hazards

  • 2017.04
    -
    2020.03

    ふじのくに地球環境史ミュージアム   教授

  • 2015.04
    -
    2017.03

    ふじのくに地球環境史ミュージアム   准教授

  • 2014.06
    -
    2017.03

    Shizuoka University   Center for Integrated Research and Education of Natural Hazards

  • 2014.06
    -
    2015.03

    静岡県ふじのくに地球環境史ミュージアム整備課   准教授

  • 2012.04
    -
    2014.05

    Waseda University   Faculty of Human Sciences

  • 2010.01
    -
    2012.03

    Naruto University of Education

  • 2009.02
    -
    2010.01

    University of Turku

  • 2005.04
    -
    2008.03

    日本学術振興会   特別研究員(PD)

  • 2003.11
    -
    2005.03

    Shimane University   Research Center for Coastal Lagoon Environments

  • 2001.04
    -
    2004.03

    日本学術振興会   特別研究員(DC)

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Education Background

  • 1999.04
    -
    2002.03

    Tokyo Metropolitan University  

  • 1997.04
    -
    1999.03

    Tokyo Metropolitan University  

  • 1993.04
    -
    1997.03

    Tokyo Metropolitan University   Faculty of Science   Department of Geography  

Committee Memberships

  • 2023.07
    -
    Now

    日本第四紀学会  庶務委員長

  • 2022.06
    -
    Now

    アースサイエンスウィーク・ジャパン実行委員会  委員長

  • 2022.04
    -
    Now

    日本地球惑星科学連合  教育国際対応小委員会委員長

  • 2021.11
    -
    Now

    社会地質学会  評議委員

  • 2024.09
    -
    Now

    日本地球惑星科学連合  教育検討委員会 委員

  • 2019.08
    -
    Now

    日本第四紀学会  評議員

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Professional Memberships

  •  
     
     

    JAPAN GEOSCIENCE UNION

  •  
     
     

    TOKYO GEOGRAPHICAL SOCIETY

  •  
     
     

    日本サイエンスコミュニケーション協会

  •  
     
     

    日本地質学会

  •  
     
     

    日本地理学会

  •  
     
     

    日本第四紀学会

  •  
     
     

    汽水域研究会

  •  
     
     

    社会地質学会

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Research Areas

  • Environmental dynamic analysis / Human geosciences / Solid earth sciences / Museology / Cultural assets study / Geography

Research Interests

  • 自然地理学

  • 環境考古学

  • 科学コミュニケーション

  • 環境史学

  • 災害史

  • 気候変動

  • 年縞

  • 湖沼堆積物

  • 古環境学

  • disastrous history

  • climate change

  • varves

  • Lake sediments

  • Paleoenvironment

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Awards

  • 社会地質学会優秀講演賞

    2021.11   社会地質学会   鹿児島県藺牟田池ボーリングコアの層序・年代と古環境学的価値について

    Winner: 山田和芳, 藺牟田池プロジェクトメンバー

  • 最優秀ポスター賞

    2019.09   日本陸水学会第84回大会   ミジンコ個体群の遺伝的多様性の歴史:湖沼堆積物と休眠卵による湖沼定着初期からの解析

    Winner: 大竹裕里恵, 大槻朝, 占部城太郎, 陶山佳久, 松尾歩, 廣田峻, 木村成子, 山田和芳, 吉田丈人

  • 最優秀ポスター賞

    2019.08   日本進化学会大21回大会   Reconstruction of population dynamics and adaptation of a Daphnia pulex population since its colonization in a new habitat: analysis using varved sediments and dormant eggs

    Winner: Yurie Otake, Hajime Ohtsuki, Jotaro Urabe, Shigeko Kimura, Kazuyoshi Yamada, Takehito Yoshida

  • 講演賞

    2018.12   社会地質学会 第28回環境地質シンポジウム   年縞にみる環境史学の現状と課題

    Winner: 山田 和芳

  • 最優秀ポスター賞

    2018.03   日本生態学会 第65回大会   トレンドとイベントから成る長期環境変動に対するプランクトン群集の応答:年縞堆積物を用い過去に遡る

    Winner: 大竹裕里恵, 大槻朝, 占部城太郎, 木村成子, 山田和芳, 吉田丈人

  • 最優秀口頭発表賞

    2017.09   日本陸水学会第82回大会   長野県深見池における長期環境変動と枝角類群集の形成過程:年縞堆積物による長期動態の解明

    Winner: 大竹裕里恵, 大槻朝, 占部城太郎, 木村成子, 山田和芳, 吉田丈人

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Media Coverage

  • 水堀の堆積物 刻まれた痕跡

    Newspaper, magazine

    Author: Other  

    共同通信   静岡新聞,東京新聞,高知新聞,福井新聞,山陽新聞  

    2022.08

  • もく夜7のシャングリ・ラ

    TV or radio program

    FM Hi   もく夜7のシャングリ・ラ クロストーク  

    2022.06

  • 駿府城お堀の水 実はきれいだった 水質調査で「知る限り全国ナンバーワン」 静岡市

    TV or radio program

    テレビ静岡  

    2022.05

  • 駿府城の堀 水質調査に着手 利活用、保全へ研究チームなど

    Newspaper, magazine

    Author: Other  

    静岡新聞  

    2021.07

  • 絶対に訪ねたくなる浜名湖展

    日本養殖新聞  

    2020.03

  • 浜名湖ウナギの歴史紹介

    静岡新聞  

    2020.03

  • カードゲームで資源考えよう

    静岡新聞  

    2020.03

  • プラごみ減 方策考える

    静岡新聞  

    2020.03

  • エシカル消費実践を 環境史ミュージアム出前教室

    富士ニュース  

    2020.02

  • はやぶさ2模型展示

    TV or radio program

    静岡朝日テレビニュース  

    2019.10

  • 学びや新章

    静岡新聞  

    2019.09

  • プラごみ減で心掛けを タリーズ中央公園店で環境教室

    富士ニュース  

    2019.09

  • オリジナルPV完成、欧州の会議の紹介

    Newspaper, magazine

    静岡新聞  

    2019.09

  • 二俣線廃止の歴史知る

    Newspaper, magazine

    中日新聞  

    2019.08

  • 特別講義「年縞が語る地球環境史」

    TV or radio program

    放送大学  

    2018

  • ブラタモリ#152浜名湖

    TV or radio program

    NHK総合  

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Papers

  • Records of environmental and ecological changes related to excavation in varve sediment from Lake Hiruga in central Japan

    Koji Seto, Kota Katsuki, Akira Tsujimoto, Junko Kitagawa, Kazuyoshi Yamada, Yoshiaki Suzuki

    Journal of Paleolimnology   68 ( 3 ) 329 - 343  2022.10  [Refereed]

    DOI

    Scopus

  • Environmental evolution and fire history of Rebun Island (Northern Japan) during the past 17,000 years based on biomarkers and pyrogenic compound records from Lake Kushu

    Masanobu Yamamoto, Fangxian Wang, Tomohisa Irino, Kazuyoshi Yamada, Tsuyoshi Haraguchi, Hideto Nakamura, Katsuya Gotanda, Hitoshi Yonenobu, Christian Leipe, Xuan-Yu Chen, Pavel E. Tarasov

    QUATERNARY INTERNATIONAL   623   8 - 18  2022.06

     View Summary

    Rebun is a small island located northwest of Hokkaido Island where hunter-fisher-gatherer cultural traditions continued until the 19th century CE. In this study, we quantified polycyclic aromatic hydrocarbons (PAHs), pentacyclic triterpene methyl ethers (PTMEs), n-fatty acids, and glycerol dialkyl glycerol tetraethers (GDGTs) in sediments from Lake Kushu in northern Rebun Island to reconstruct changes in limnology, the local environment and local to regional fire activities during the past 17,000 years (i.e., 17 ka). The PAH concentration increased from 11 to 10 cal ka BP. PAH and PTME compositions indicate that this change was associated with an increase of fire activity at proximal locations (i.e., the vicinity of Lake Kushu) and a change in the composition of grasses growing around the lake. A peak in PAH concentrations at 6.6-6.0 cal ka BP likely indicates intensive fire activity on Rebun Island. The PAH composition after 6 cal ka BP mainly reflected the combustion of conifers near the lake. The GDGTs, n-fatty acids, perylene, and PTME concentrations were higher around 10 cal ka BP and after 6 cal ka BP compared to the remaining periods, suggesting better preservation of those compounds under lake conditions marked by lower oxygen concentrations.

    DOI

    Scopus

    3
    Citation
    (Scopus)
  • 総特集「基礎データから考える第四紀の新展開 -Ⅲ古環境復元の様々なプロキシ(2)」について(エピローグ)

    奥野充, 黒木貴一, 藤木利之, 中西利典, 山田和芳

    月刊地球   44   249 - 251  2022.06

  • Population genetic dynamics during colonisation and establishment of an obligate parthenogenetic Daphnia pulex population in a small lake of a continental archipelago

    Yurie Otake, Hideki Innan, Hajime Ohtsuki, Jotaro Urabe, Kazuyoshi Yamada, Takehito Yoshida

    Freshwater Biology   67 ( 8 ) 1428 - 1438  2022.06  [Refereed]

     View Summary

    Population genetic diversity and structure are known to influence successful colonisation and establishment of a population in a novel habitat. However, our understanding of actual population genetic changes in the early stage of colonisation and detailed time-series of genetic changes during the establishment of a new population is still limited due to the difficulty of making long-term direct observations of a colonising population. Using a paleolimnological approach, we revealed the long-term genetic dynamics of an obligate parthenogenetic panarctic Daphnia pulex population during the early stage of colonisation and subsequent establishment in Lake Fukami-ike of Nagano, Japan. We collected diapausing eggs in ephippia of D. pulex from layers of sediment core samples (c. 370 cm long; dated 1662-2017) and then the mitochondrial DNA was sequenced using the markers designed for the NADH dehydrogenase 5 (ND5) gene and the control region. Daphnia pulex colonised and established a population in the early 2000s. Population genetic analysis showed that one colonising haplotype predominated in the population throughout the study period. Genetic diversity was consistently limited and there was no recovery of genetic diversity after colonisation. Clearly limited genetic diversity did not hamper population growth, possibly because phenotypic plasticity was used to cope with changes in predation pressure. Analysis using multivariate auto-regressive models showed that responses to environmental and ecological factors varied depending on the haplotype, which may have contributed to successful colonisation of the lake by the different haplotypes. The present results suggest that an obligate parthenogenetic population can establish in a new habitat and be maintained for generations even though it has limited genetic diversity. We found that two independent lineages (JPN1 and JPN2) successfully established and coexisted toward the end of the study period. Although limited genetic diversity did not impede colonisation success, how the later colonising JPN1 lineage has successfully invaded a population consisting solely of the early colonising JPN2 deserves future attention to understand the population genetic dynamics revealed in this study.

    DOI

    Scopus

    4
    Citation
    (Scopus)
  • 総特集「基礎データから考える第四紀の新展開 -Ⅱ火山の地形・地質・年代」について

    奥野充, 黒木貴一, 藤木利之, 中西利典, 山田和芳

    月刊地球   44   127 - 130  2022.04

  • Late-Holocene salinity changes in Lake Ogawara, Pacific coast of northeast Japan, related to sea-level fall inferred from sedimentary geochemical signatures

    Fumiko Watanabe Nara, Takahiro Watanabe, Tetsuya Matsunaka, Shin-ichi Yamasaki, Noriyoshi Tsuchiya, Koji Seto, Kazuyoshi Yamada, Yoshinori Yasuda

    Palaeogeography, Palaeoclimatology, Palaeoecology   592   110907 - 110907  2022.04  [Refereed]

     View Summary

    This study aimed to provide important insights into Pacific Ocean sea-level changes by clarifying salinity changes in Lake Ogawara on the Pacific coast of northeast Japan, which became brackish in the late Holocene. Radiocarbon (14C) dating, tephrochronology, and geochemical signatures, including bromine (Br), iodine (I), total sulfur (TS), total organic carbon (TOC), and total nitrogen (TN), were applied to continuous sediment core from Lake Ogawara to estimate salinity changes. The core has two tephra layers, the Towada eruption (To-a; approximately 915 CE) and the Changbaishan eruption (B-Tm; 946 CE). An age model for the core was established using plant macro remain 14C ages constrained by a B-Tm tephra. The depletion of marine-derived elements (Br, I, and TS) was observed in 2200–2000 cal BP layers, indicating a paleosalinity change from saline to brackish conditions caused by falling sea levels during the late Holocene. Variations in Br, I, TOC, and TN concentrations were significantly changed compared to those below the B-Tm layer. High correlations between Br and TOC and I and TOC above the B-Tm tephra layer to the surface indicated an organic source for the halogens post the Changbaishan eruption, indicating a change to the hydrological system of the lake's watershed. The increasing variation in the C/N atomic ratio in the post-B-Tm sediments also supported this hydrological change. Two recorded significant volcanic eruptions could have triggered these changes to the Lake Ogawara water inflow system.

    DOI

    Scopus

    4
    Citation
    (Scopus)
  • 裾野市茶畑山出土埋没木の保存と活用

    大森信宏, 山田和芳, 西岡佑一郎

    静岡県埋蔵文化財センター研究紀要   8   25 - 28  2022.03

  • Tepha beds during the pre-caldera formation in north and west parts of the Izu-Oshima volcano, Japan

    寺山怜, 小林淳, 村田昌則, 高橋尚志, 鈴木毅彦

    月刊地球   44 ( 号外71 ) 7 - 10  2022.01

    J-GLOBAL

  • Uチャネル試料を利用した藺牟田池コアの磁気特性の研究

    林田 明, 横田敬作, 山田和芳

    号外地球   ( 71 ) 107 - 111  2022.01

  • ASGM(人力小規模金採掘)に関連した環境汚染研究における湖沼掘削科学の貢献と役割

    山田和芳, 村尾 智, 冨安卓滋, 奥野 充, 瀬戸浩二, 香月興太, 中西利典, 加田 渉

    号外地球   ( 71 ) 70 - 77  2022.01

    Authorship:Lead author, Corresponding author

  • Long-term changes in morphological traits of Daphnia pulex in Lake Fukami-ike, Japan

    Yurie Otake, Hajime Ohtsuki, Jotaro Urabe, Kazuyoshi Yamada, Takehito Yoshida

    Limnology   22 ( 3 ) 329 - 336  2021.08  [Refereed]

     View Summary

    How a population adapts to environmental changes is a central topic in ecology, but long-term changes in the phenotype of an organism have rarely been studied in aquatic systems. In this study, we examined the morphological changes in Daphnia pulex from the initial establishment stage, using paleolimnological analysis, in Lake Fukami-ike (Nagano Prefecture, Japan). We measured morphological traits of ephippia and subfossils of D. pulex and compared the results with the population dynamics assessed in an earlier study. D. pulex established a stable population in the lake in the early 2000s. The length of the ephippia significantly increased in the mid-2000s and then decreased more recently, whereas the length of the post-abdominal claw as a proxy of body size did not show significant changes. This suggests that their adult body size was larger, and the time to maturity was delayed or the shift to the dormant phase got later in the mid-2000s, although the mean body size did not change. Subfossils of Chaoborus and the historical records suggest that planktivorous fish were less abundant and Chaoborus larvae were more abundant in the mid-2000s than in more recent periods. These results suggest that D. pulex adaptively changed phenotypic traits in response to changes in the predator community in the studied lake.

    DOI

    Scopus

    2
    Citation
    (Scopus)
  • A Lacustrine Biomarker Record From Rebun Island Reveals a Warm Summer Climate in Northern Japan During the Early Middle Holocene Due to a Stronger North Pacific High

    Masanobu Yamamoto, Fangxian Wang, Tomohisa Irino, Kenta Suzuki, Kazuyoshi Yamada, Tsuyoshi Haraguchi, Katsuya Gotanda, Hitoshi Yonenobu, Xuan Yu Chen, Pavel Tarasov

    Frontiers in Earth Science   9  2021.06  [Refereed]

     View Summary

    The summer climate of northern Japan since the last glacial period has likely been determined by atmospheric and oceanic dynamics, such as changes in the North Pacific High, the position of the westerlies, the Kuroshio Current, the Tsushima Warm Current (TWC), and the East Asian summer monsoon. However, it is unclear which factor has been most important. In this study, we analyzed leaf wax δ13C and δD and glycerol dialkyl glycerol tetraethers (GDGTs) in sediments from Lake Kushu, Rebun Island, northern Japan, and discuss changes in climate over the past 17,000 years. The GDGT-based temperature, the averaged chain length, δ13C and δD of long-chain n-fatty acids indicated that the climate was cold during the Oldest Dryas period ∼16 ka and warm in the early Middle Holocene from ∼9 to 6 ka. This climate change is consistent with the sea surface temperature in the Kuroshio–Oyashio transition, but inconsistent with changes in the TWC in the Sea of Japan. The results imply that the summer climate of northern Japan was controlled mainly by changes in the development of the North Pacific High via changes in the position of the westerly jet and East Asian summer monsoon rainfall, whereas the influence of the TWC was limited over a millennial timescale.

    DOI

    Scopus

    4
    Citation
    (Scopus)
  • Characteristics in trace elements compositions of tephras (B-Tm and To-a) for identification tools

    Fumiko Watanabe Nara, Tatsunori Yokoyama, Shin-ichi Yamasaki, Masayo Minami, Yoshihiro Asahara, Takahiro Watanabe, Kazuyoshi Yamada, Noriyoshi Tsuchiya, Yoshinori Yasuda

    Geochemical Journal   55 ( 3 ) 117 - 133  2021.06  [Refereed]

     View Summary

    The absolute date of the Millennium Eruption (ME) of Changbaishan Volcano is widely recognized as AD 946. The Baegdusan-Tomakomai (B-Tm) tephra dispersed during the ME is a robust-age key bed. In order to identify the tephra, refractive index and major- element compositions of volcanic glass shards are conventionally used. Meanwhile, traceelement analysis using the inductively coupled plasma mass spectrometry (ICP- MS) technique for the volcanic glass shards and bulk samples of the B- Tm tephra is still limited. Here we give a detailed description of major- and traceelement compositions for the glass shards and bulk sediments of the B-Tm and Towada caldera eruptions (To-a) tephra deposits from the Lake Ogawara sediment core, Tohoku region, northern Japan to identify the tephras. The depth profiles of the major and trace elements show the significant peaks for the K2O and some trace elements (Zn, Rb, Zr, Nb, Sn, Y, La, Ce, Nd, Th, and U) at the B-Tm tephra layer in the Lake Ogawara sediment core, but no peaks of these elements at the Toa tephra layer. High concentrations of the trace elements in the B- Tm tephra layer were observed in individual glass shards as well as in the bulk sediment. These concentrations are highlighted by the elemental abundance pattern normalized by the crustal abundance. The elemental pattern in individual glass shards from other Japanese tephras showed significant differences from those of the B-Tm tephra, especially in REE compositions. The trace-element compositions of the glass shards and bulk sediments show a strong tool for distinguishing the B-Tm tephra from other Japanese tephras.

    DOI

    Scopus

    6
    Citation
    (Scopus)
  • 博物館における小学生を対象としたSTEM/STEAM教育プログラムの開発と実践-博物館ならではの科学教室の在り方の模索-

    坂田尚子, 池谷 渉, 菅原大助, 山田和芳, 熊野善介

    静岡県博物館協会研究紀要   44   56 - 61  2021.03

  • Long-term dynamics of a cladoceran community from an early stage of lake formation in Lake Fukami-ike, Japan

    Yurie Otake, Hajime Ohtsuki, Jotaro Urabe, Shigeko Kimura, Kazuyoshi Yamada, Takehito Yoshida

    Ecology and Evolution   11 ( 3 ) 1240 - 1253  2021.02  [Refereed]

     View Summary

    An increase in nutrient levels due to eutrophication has considerable effects on lake ecosystems. Cladocerans are intermediate consumers in lake ecosystems; thus, they are influenced by both the bottom-up and top-down effects that occur as eutrophication progresses. The long-term community succession of cladocerans and the effects cladocerans experience through the various eutrophication stages have rarely been investigated from the perspective of the early-stage cladoceran community assemblage during lake formation. In our research, long-term cladoceran community succession was examined via paleolimnological analysis in the currently eutrophic Lake Fukami-ike, Japan. We measured the concentration of total phosphorus and phytoplankton pigments and counted cladoceran and other invertebrate subfossils in all layers of collected sediment cores, and then assessed changes in the factors controlling the cladoceran community over a 354-year period from lake formation to the present. The cladoceran community consisted only of benthic taxa at the time of lake formation. When rapid eutrophication occurred and phytoplankton increased, the benthic community was replaced by a pelagic community. After further eutrophication, large Daphnia and high-order consumers became established. The statistical analysis suggested that bottom-up effects mainly controlled the cladoceran community in the lake's early stages, and the importance of top-down effects increased after eutrophication occurred. Total phosphorus and phytoplankton pigments had positive effects on pelagic Bosmina, leading to the replacement of the benthic cladoceran community by the pelagic one. In contrast, the taxa established posteutrophication were affected more by predators than by nutrient levels. A decrease in planktivorous fish possibly allowed large Daphnia to establish, and the subsequent increase in planktivorous fish reduced the body size of the cladoceran community.

    DOI

    Scopus

    6
    Citation
    (Scopus)
  • Tsunamis and submarine landslides in Suruga Bay, central Japan, caused by Nankai–Suruga Trough megathrust earthquakes during the last 5000 years

    Akihisa Kitamura, Kazuyoshi Yamada, Daisuke Sugawara, Yusuke Yokoyama, Yosuke Miyairi, Miki Hirakawa, Daichi Iwatsuki, Satoru Katagiri, Masaya Maeda, Hideki Mori, Yuki Nakai, Sota Okazaki, Yui Sakamoto, Masaki Sasada, Yusuke Seki, Youki Takikawa, Yuka Yamamoto, Yuki Yoda

    Quaternary Science Reviews   245   106527 - 106527  2020.10  [Refereed]

     View Summary

    Magnitude 8 megathrust earthquakes that have generated large tsunamis with wave heights of >5 m in coastal areas of southwestern Japan have occurred every 100–150 years along the Nankai–Suruga Trough, which marks the convergent boundary between the Eurasian and Philippine Sea plates. Using sedimentological, geochemical, and paleontological analyses, as well as 14C dating, we examined tsunami deposits in 12 sediment cores collected from the Hamatome lowland, Yaizu Plain, Shizuoka, which faces the Suruga Trough. Four sandy tsunami deposits (Sands 1–4) are identified in sediments deposited during the last 5000 years. Sand 1 was deposited between 805 and 405 BC, suggesting that only one tsunami left a sedimentological imprint in the Hamatome lowland lagoon during the period of ∼4000 years between 3090 and 2913 BC and the AD 1096 Eicho-Tokai earthquake. This very low frequency of tsunami inundation may suggest that this tsunami was larger than those typically associated with megathrust earthquakes. Sands 2–4 are correlated with tsunamis associated with the Eicho-Tokai, AD 1361 Shohei-Koan, and AD 1498 Meio-Tokai earthquakes, respectively. Our data indicate that a sand spit, which had previously protected the lagoon from oceanic waves, was abruptly destroyed following the AD 1096 Eicho-Tokai earthquake and did not re-form at the same location. This disappearance of the sand spit is inferred to have involved an earthquake-induced submarine landslide. The data presented in this paper, together with information obtained from historical documents, indicates that M8 megathrust earthquakes in AD 1096 and AD 1498 caused submarine landslides in the study area, resulting in coastal subsidence and damage to coastal areas additional to that caused by the tsunamis.

    DOI

    Scopus

    10
    Citation
    (Scopus)
  • 三方五湖の堆積物に記録される洪水と花粉分析から推測されるその植生への影響

    北川淳子, 瀬戸浩二, 篠塚良嗣, 山田和芳, 吉田丈人

    環境考古学と富士山   4   11 - 19  2020.03

  • 湖沼堆積物と生物遺骸が可能にする長期進化生態学的研究

    大竹裕里恵, 大槻 朝, 占部城太郎, 木村成子, 山田和芳, 吉田丈人

    環境考古学と富士山   4   42 - 52  2020.03

  • 北海道網走湖における年縞堆積物の特徴と近年の環境変化

    瀬戸浩二, 香月興太, 北川淳子, 園田 武, 山田和芳, 川尻敏文

    環境考古学と富士山   4   53 - 65  2020.03

  • 熊本県天草諸島下島・池田池における過去7,500年間の珪藻化石群集変動

    福本 侑, 箕田友和, 鹿島 薫, 原口 強, 山田和芳

    環太平洋文明研究   4   60 - 75  2020.03  [Refereed]

  • 地理学者がみた富士宮のここがすごい-富士山の恩恵と禍害-

    山田和芳

    環境考古学と富士山   4   76 - 85  2020.03

    Authorship:Lead author

  • Geologic evidence for coseismic uplift at ~ AD 400 in coastal lowland deposits on the Shimizu Plain, central Japan

    Akihisa Kitamura, Tomoya Ina, Daisuke Suzuki, Keito Tsutahara, Daisuke Sugawara, Kazuyoshi Yamada, Akira Aoshima

    Progress in Earth and Planetary Science   6 ( 1 )  2019.12  [Refereed]

     View Summary

    Megathrust earthquakes of magnitude ~ 8 and ensuing large tsunamis occur along the Nankai and Suruga troughs, central Japan, with a recurrence interval of 90–270 years since an AD 684 Hakuho earthquake. Historical records show that the AD 1854 Ansei-Tokai earthquake caused coseismic uplift of ~ 1 m in coastal areas west of Suruga Bay, including the Shimizu Plain, east Shizuoka Prefecture. The 1361 Shohei Tokai earthquake was accompanied by coseismic uplift, but no evidence has been found to indicate uplift before the earthquake. This study examined sediment cores recovered from the coastal beach ridge in the Shimizu Plain using sedimentological and paleontological analyses and radiocarbon dating. We infer from the results that a relative sea-level fall of 1.6 m took place at AD 398–428. This coincides with archeological evidence suggesting the occurrence of a large earthquake in west Shizuoka Prefecture in AD 400. This combination of evidence indicates that the drop in sea level was caused by coseismic uplift associated with a megathrust rupture along the Suruga Trough, with a recurrence interval of ~ 500–1000 years. The results also indicate that a megathrust rupture occurred in the region from the Eastern Nankai Trough to the Suruga Trough at ca. AD 400. [Figure not available: see fulltext.].

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    7
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  • 年縞を用いた自然・人間環境史

    山田和芳

    月刊地球   482   631 - 637  2019.11

    Authorship:Lead author

  • 総論:島嶼環境史学の創成-人類世を豊かに生きるために-

    山田和芳, 奥野 充

    月刊地球   482   627 - 630  2019.11

    Authorship:Lead author

  • Combined analysis of sulfur and carbon contents, and foraminifer as paleoenvironmental indicators in tidal flat sediments on Miura Peninsula, Japan

    Akihisa Kitamura, Yuka Yamamoto, Kazuyoshi Yamada, Atsushi Kubo, Takashi Toyofuku, Yuki Nakagawa

    Estuarine, Coastal and Shelf Science   226  2019.10  [Refereed]

     View Summary

    Reconstruction of natural hazards from tidal flat sediments is essential for assessment of coastal hazards, and is based on knowledge of recent sediments. This study therefore examined recent sediments deposited on a narrow, muddy tidal flat on Miura Peninsula, metropolitan Tokyo, Japan, by means of sedimentological analysis, C, N, and S elemental analysis, carbonate content, 137Cs dating, and analysis of benthic foraminifera (species composition and degree of preservation). 137Cs profiles of four sediment cores of ∼20 cm in length showed that the sediments were deposited after the release of 137Cs by the accident at the Fukushima No. 1 Nuclear Power caused by the Tohoku-oki tsunami at March 2011. Results of C/S ratios of mud fractions indicated that the intertidal deposits in the central bay are characterized by low C/S ratios (4.9–11.4) and the bayhead deposits of the upper intertidal and supratidal zones by higher ratios (13.9–24.9). A fluid–mud layer identified in the central bay had the same C/S ratios and carbonate contents as marine sediments, indicating that the fluid-mud deposits probably resulted from resuspension of mud caused by storm-wave action after March 2011. Faunal analysis of benthic foraminifera showed that very low density of foraminifera can be regarded as one of the defining characteristics of fluid-mud deposits.

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    9
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  • マヤ低地に眠る奇跡の地層—刻まれた気候変動の足跡

    北場育子, 大森貴之, 星野安治, 原口強, 中川毅, 那須浩郎, ヘンリー・ラム, 五反田克也, 林田明, デイビッド・デットマン, 篠塚良嗣, 山田和芳, 藤木利之, 大山幹成, フローリー・ピンソン, 猪俣健, 青山和夫, 米延仁志

    古代アメリカの比較文明論:メソアメリカとアンデスの過去から現代まで   -   48 - 60  2019.09

  • Climate change during the Little Ice Age from the Lake Hamana sediment record

    Ara Cho, Kaoru Kashima, Koji Seto, Kazuyoshi Yamada, Takumi Sato, Kota Katsuki

    Estuarine, Coastal and Shelf Science   223   39 - 49  2019.07  [Refereed]

     View Summary

    Paleoenvironment and paleoclimate changes during the Little Ice Age (LIA)were investigated using sediments from Lake Hamana. This lagoon in central Japan is under a complicated climate system influenced by the East Asian summer monsoon (EASM), East Asian winter monsoon (EAWM), and strong typhoon events. Diatom assemblages and chemical components of a 1.3 m sediment core suggest historical events of rapid salination and cyclical ecosystem shifts accompanied by monsoon condition changes. Most research has indicated that Lake Hamana changed from a freshwater lake to a brackish lagoon because of the Meio earthquake in 1498 CE. However, based on results from the diatom assemblage and chemical components, this salination occurred because of changes in the Hamana paleoriver flow, and this change happened before the earthquake, around the mid-15th century. Furthermore, it is clear that Lake Hamana was an oligohaline lagoon before salination. The lithology of the lake sediments and the diatom assemblage changed during the LIA; sand, water, and total diatom contents decreased. However, the relative abundance of marine diatom taxa increased during the LIA. These changes were introduced by a weakening EASM coupled with low precipitation under low solar activity during the LIA. Several flood events represented by freshwater diatom taxa and magnetic susceptibility peaks co-occurred with strong El Niño events during the LIA. It is inferred that this strong El Niño during the LIA induced frequent typhoons causing floods in central Japan.

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    12
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  • Carbon cycle dynamics linked with Karoo-Ferrar volcanism and astronomical cycles during Pliensbachian-Toarcian (Early Jurassic)

    Masayuki Ikeda, Rie S. Hori, Minoru Ikehara, Ren Miyashita, Masashi Chino, Kazuyoshi Yamada

    Global and Planetary Change   170   163 - 171  2018.11  [Refereed]

     View Summary

    One of the most profound environmental changes in the Mesozoic occurred during the Pliensbachian-Toarcian (Pl/To) time interval, including massive black shale deposition across Pl/To boundary and early Toarcian Oceanic Anoxic Event (T-OAE). These events are associated with negative carbon isotope excursions (CIEs), but their temporal link with 12C-rich carbon injection, possibly related with Karoo-Ferrar volcanisms and carbon cycle feedbacks, such as terrestrial methanogenesis and methane hydrate dissociation, is still debated. Here we present a new chemostratigraphy of the carbon isotopic ratio of organic matter (δ13Corg) from Pl/To deep-sea successions, in conjunction with bio-astrochronology. The deep-sea successions are located at the Katsuyama and Sakahogi outcrops in the Inuyama area, Japan, and contain two black bedded chert intervals named T-BBCs 1 and 2, which have astrochronologic ages of 183.25–183.01 ± 0.2 Ma and 183.55–182.80 ± 0.2 Ma. Negative CIEs of ~2‰ and ~5‰ are recognized across the base of T-BBCs 1 and 2, respectively, which are correlated with Pl/To boundary and classical T-OAE in shallow marine sections based on biostratigraphy. Astrochronologic ages of the onset of T-BBCs 1 and 2 are within the errors of the oldest high-precision U-Pb ages of Karoo and Ferrar LIPs, respectively. These temporal relations suggest a link between the 12C-rich carbon injection associated with Karoo and Ferrar volcanism, and CIEs associated with widespread black shale deposition across the Pl/To and T-OAE, respectively. Obliquity cycles in classic T-OAE CIE could have linked with terrestrial methanogenesis and methane hydrate dissociation in high-latitudes areas, whereas 405-kyr pacing of termination of T-CIE and T-BBCs deposition would be related with decreased chemical weathering and nutrient supply under weaker monsoon intensity, and possibly suppressed methane cycle across the termination of Pl/To and T-OAE periods.

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    38
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  • Carbon cycle dynamics linked with Karoo-Ferrar volcanism and astronomical cycles during Pliensbachian-Toarcian (Early Jurassic)

    責任著者, 池田 昌之, 共著者, 堀利栄, 池原実, 山田和芳, 宮下怜, 千野将史

    Global Planetary Change   410 ( (num) ) 134 - 142  2018.08  [Refereed]

  • Widespread occurrence of distinct alkenones from Group I haptophytes in freshwater lakes: Implications for paleotemperature and paleoenvironmental reconstructions

    William M. Longo, Yongsong Huang, Yuan Yao, Jiaju Zhao, Anne E. Giblin, Xian Wang, Roland Zech, Torsten Haberzettl, Ludwig Jardillier, Jaime Toney, Zhonghui Liu, Sergey Krivonogov, Marina Kolpakova, Guoqiang Chu, William J. D'Andrea, Naomi Harada, Kana Nagashima, Miyako Sato, Hitoshi Yonenobu, Kazuyoshi Yamada, Katsuya Gotanda, Yoshitsugu Shinozuka

    Earth and Planetary Science Letters   492   239 - 250  2018.06  [Refereed]

     View Summary

    Alkenones are C35–C42 polyunsaturated ketone lipids that are commonly employed to reconstruct changes in sea surface temperature. However, their use in coastal seas and saline lakes can be hindered by species-mixing effects. We recently hypothesized that freshwater lakes are immune to species-mixing effects because they appear to exclusively host Group I haptophyte algae, which produce a distinct distribution of alkenones with a relatively consistent response of alkenone unsaturation to temperature. To evaluate this hypothesis and explore the geographic extent of Group I haptophytes, we analyzed alkenones in sediment and suspended particulate matter samples from lakes distributed throughout the mid- and high latitudes of the Northern Hemisphere (n=30). Our results indicate that Group I-type alkenone distributions are widespread in freshwater lakes from a range of different climates (mean annual air temperature range: −17.3–10.9 °C; mean annual precipitation range: 125–1657 mm yr−1; latitude range: 40–81°N), and are commonly found in neutral to basic lakes (pH > 7.0), including volcanic lakes and lakes with mafic bedrock. We show that these freshwater lakes do not feature alkenone distributions characteristic of Group II lacustrine haptophytes, providing support for the hypothesis that freshwater lakes are immune to species-mixing effects. In lakes that underwent temporal shifts in salinity, we observed mixed Group I/II alkenone distributions and the alkenone contributions from each group could be quantified with the RIK37 index. Additionally, we observed significant correlations of alkenone unsaturation (U37K) with seasonal and mean annual air temperature with this expanded freshwater lakes dataset, with the strongest correlation occurring during the spring transitional season (U37K=0.029⁎T−0.49; r2=0.60; p<0.0001). We present new sediment trap data from two lakes in northern Alaska (Toolik Lake, 68.632°N, 149.602°W; Lake E5, 68.643°N, 149.458°W) that demonstrate the highest sedimentary fluxes of alkenones in the spring transitional season, concurrent with the period of lake ice melt and isothermal mixing. Together, these data provide a framework for evaluating lacustrine alkenone distributions and utilizing alkenone unsaturation as a lake temperature proxy.

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    57
    Citation
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  • 天草諸島・池田池の湖底ボーリングコア中における明暗互層の形成過程

    箕田友和, 鹿島薫, 原口強, 吉永祐一, 山田和芳

    地形   39 ( 2 ) 205  2018.04

    J-GLOBAL

  • 浜名湖の湖底地形(1)湖心部

    山田 和芳

    東海自然誌   11   9 - 14  2018.03  [Refereed]

  • Paleoenvironment of the Matsue plains, Shimane prefecture, southwest Japan (5)

    Watanabe Masami, Seto Koji, Takayasu Katsumi, Yamada Kazuyoshi, Okunaka Ryouta

    Annual Meeting of the Geological Society of Japan   2018 ( 0 ) 307 - 307  2018

     View Summary

    [Program canceled for a disaster] Program canceled for the 2018 Hokkaido Eastern Iburi earthquake. However, This abstract is quotable and viewable on PDF.

    DOI CiNii

  • 国際火山噴火史情報研究‐I―火山噴火と自然環境,情報研究,アウトリーチ,防災・減災―フィリピン・ラグナ州,サンパブロ湖沼群の音波探査調査に基づく湖底地形と形成期の推定

    山田和芳, 原口強, MAXIMO Raymo, Patrick R, RIVERA Danikko John V, LIM Robjunelieaaa B, POGAY Cathy D, QUILALAN Marie Thess D, MITIAM Emmanuelle D, BARISO Ericson, 藤木利之, 中村俊夫, 奥野充, 小林哲夫

    月刊地球     36‐41  2017.06

    J-GLOBAL

  • 国際火山噴火史情報研究‐I―火山噴火と自然環境,情報研究,アウトリーチ,防災・減災―フィリピン・ラグナ州,サンパブロ湖沼群から得たピストンコア試料の層序と物性

    中西利典, 山田和芳, 原口強, BARISO Ericson, RIVERA Danikko John V, LIM Robjunelieaaa B, POGAY Cathy D, QUILALAN Marie Thess D, 奥野充, 藤木利之, 中村俊夫, 小林哲夫

    月刊地球     42‐46  2017.06

    J-GLOBAL

  • Estuary and environmental history: a case study of geomorphological development in the Izumo Plain

    山田和芳, 高安克己

    環境考古学と富士山   ( 1 ) 60‐75  2017.03

    J-GLOBAL

  • The reconstruction of paleoenvironmental change using the core sediments of Lakes Hyuga, Kugushi, Suga, and Mikata

    篠塚良嗣, 山田和芳, 入澤汐菜, 瀬戸浩二, 北川淳子

    環太平洋文明研究   ( 1 ) 93‐104,1(2)  2017.02

    J-GLOBAL

  • Paleoenvironment of the Matsue plains, Shimane prefecture, southwest Japan (4)

    Watanabe Masami, Seto Koji, Takayasu Katsumi, Yamada Kazuyoshi, Okunaka Ryota

    Annual Meeting of the Geological Society of Japan   2017 ( 0 ) 278 - 278  2017

     View Summary

    [Program canceled for typhoon] Program canceled for typhoon. However, This abstract is quotable and viewable on PDF.

    DOI CiNii

  • Lake varves and environmental history

    Kazuyoshi Yamada

    Multidisciplinary Studies of the Environment and Civilization: Japanese Perspectives     24 - 42  2017.01  [Refereed]

     View Summary

    Varves (annually laminated sediments) are one of the most important terrestrial archives of past environments with an annual- to century-scale resolution (Brauer 2004). Sediments from small and deep maar lakes have great potential in this respect due to their specific conditions for the formation and preservation of the laminated sediments (Zolitschka and Negendank 1996; Zolitschka et al. 2000; Mingram et al. 2004).

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  • Mass accumulation rate of detrital materials in Lake Suigetsu as a potential proxy for heavy precipitation: a comparison of the observational precipitation and sedimentary record

    Yoshiaki Suzuki, Ryuji Tada, Kazuyoshi Yamada, Tomohisa Irino, Kana Nagashima, Takeshi Nakagawa, Takayuki Omori

    Progress in Earth and Planetary Science   3 ( 1 )  2016.12  [Refereed]

     View Summary

    In the densely populated region of East Asia, it is important to know the mechanism, scale, and frequency of heavy precipitation brought about during the monsoons and typhoons. However, observational data, which cover only several decades, are insufficient to examine the long-term trend of extreme precipitation and its background mechanism. In humid areas, the transport flux of a suspended detrital material through a river system is known to have an empirical power relationship with precipitation. Thus, the sedimentation flux of a fine detrital material could potentially be used as a proxy for reconstructing past heavy precipitation events. To test the idea that the sedimentation flux of detrital materials records past heavy precipitation events (e.g., typhoons), we focused on the detrital flux estimated from the annually laminated sediment of Lake Suigetsu, central Japan, which is capable of accurately correlating the age of detrital flux with the precipitation record. We first established a precise age model (error within ±1 year in average) beginning in 1920 A.D. on the basis of varve counting fine-tuned by correlation between event layers with historical floods. The flux of the detrital material (g/cm2/year) was estimated on the basis of Al2O3 content (wt%), dry bulk density (g/cm3), and sedimentation rate (cm/year) calculated from the age model. The detrital flux of background sedimentation showed a weak positive correlation with annual and monthly (June and September) precipitation excluding heavy precipitation that exceeded 100 mm/day. Furthermore, the thickness of instantaneous event layers, which corresponds to several maxima of detrital flux and is correlated with floods that occurred mainly during typhoons, showed a positive relationship with the total amount of precipitation that caused a flood event. This result suggests that the detrital flux maxima (deposition of event layers) record past extreme precipitation events that were likely associated with typhoons that hit the middle part of Honshu Island. Based on this result, the record of typhoon-caused flood events can go back to older period (e.g., last glacial period) on the basis of the occurrence, and thickness, or mass flux of event layers using long sediment cores from Lake Suigetsu.

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    16
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  • Understanding the human impact on Akita-sugi cedar (Cryptomeria japonica) forest in the late Holocene through pollen analysis of annually laminated sediments from Ichi-no-Megata, Akita, Japan

    Junko Kitagawa, Yoshimune Morita, Miroslaw Makohonienko, Katsuya Gotanda, Kazuyoshi Yamada, Hitoshi Yonenobu, Ikuko Kitaba, Yoshinori Yasuda

    Vegetation History and Archaeobotany   25 ( 6 ) 525 - 540  2016.11  [Refereed]

     View Summary

    Akita-sugi (Cryptomeria japonica, Japanese cedar that is grown in Akita) forests are among the most important for commercially valuable timber in Japan. Historically, these forests have been severely exploited, although now some parts of them are conserved. It is important to know the detailed history of the forests in order to utilize them sustainably in the future. This study analyzes the pollen in an annually laminated lake sediment core from Ichi-no-Megata on the Oga peninsula, Akita, Japan, to understand the history of Akita-sugi cedar forests. An age-depth model was developed based on the results of an accelerator mass spectrometer dating of 13 plant macrofossils from the surface to 422 cm in depth, the Towada-a tephra and other well-known event layers. The dominant pollen taxa were Cryptomeria and Fagus crenata by ad 1000. The first increase of Cryptomeria was detected around 1700 bc. By the 1st century ad, Cryptomeria forest was established. At that time, Cryptomeria was mixed with deciduous trees, mainly F. crenata. The pollen analysis found evidence that the main loss of woodland occurred during the 11th century ad, when forest lands were cleared for agriculture. Substantial natural forests nevertheless remained until the 16th century, after which forest resources were exhausted. Conservation and plantation activities took place later, but human activity in response to severe famines prevented the recovery of the forests. After the famine periods, the remaining forests recovered to their previous condition, but after World War II, the natural forests shrank further and plantation forests without deciduous trees were established over large areas.

    DOI

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    2
    Citation
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  • Asian dust transport during the last century recorded in Lake Suigetsu sediments

    Kana Nagashima, Yoshiaki Suzuki, Tomohisa Irino, Takeshi Nakagawa, Ryuji Tada, Yukari Hara, Kazuyoshi Yamada, Yasunori Kurosaki

    Geophysical Research Letters   43 ( 6 ) 2835 - 2842  2016.03  [Refereed]

     View Summary

    Asian dust has a significant impact on the natural environment. Its variability on multiple timescales modulates the ocean biogeochemistry and climate. We demonstrate that temporal changes in the deposition flux of Aeolian dust recorded in sediments from Lake Suigetsu, central Japan, during the last century exhibit a continuous decreasing trend and a decadal-scale decrease in 1952-1974. The former decreasing trend can be explained by a decrease in the dust storm frequency at source regions due to the warming of Mongolia in the twentieth century, suggesting future decrease of Asian dust transport with further warming in Mongolia. Decadal-scale decrease of Aeolian dust is explained by weaker westerlies in lower latitudes in central Japan, reflecting a weaker Aleutian Low during the corresponding period. Decadal-scale westerly change probably causes north-south shifts of the dominant dust transport path, which affects subarctic northern Pacific Ocean biogeochemistry by changing the micronutrient iron supply.

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    18
    Citation
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  • ふじのくに地球環境史ミュージアム紹介—Introduction of Museum of Natural and Environmental History, Shizuoka

    山田 和芳

    社会地質学会誌 = Geo-pollution science, medical geology and urban geology / 社会地質学会 編   12 ( 3・4 ) 41 - 44  2016

    CiNii

  • Magnetic properties of surficial sediments in Lake Ogawara on the Pacific coast of northeastern Japan: Spatial variability and correlation with brackish water stratification Geomagnetism

    Akira Hayashida, Ryoma Nakano, Aya Nagashima, Koji Seto, Kazuyoshi Yamada, Hitoshi Yonenobu

    Earth, Planets and Space   67 ( 1 )  2015.12  [Refereed]

     View Summary

    To examine limnological conditions in Lake Ogawara on the Pacific coast of northwestern Japan, we investigated the magnetic properties of dredged bottom sediment originally collected from the lake in the summer of 2011. We used non-destructive methods to measure the low-field magnetic susceptibility shortly after sampling, and anhysteretic remanent magnetization (ARM) was assessed in 2012 and 2015. The ARM acquisition and demagnetization curves from littoral sites showed several patterns that reflect the provenance of the sediments. At water depths below 10 m, the magnetic susceptibility and ARM of greenish black mud with high organic content decreased considerably with the increase in water depth, but ARM increased slightly at water depths greater than 16 m. We also found that the magnetic concentrations of mud samples were reduced markedly during a period of storage for about 3 years. We attributed these reductions to diagenetic loss of magnetic minerals, which had been enhanced at deeper sites. It is possible that the ARM carriers in deeper areas were derived from authigenic formation of iron sulfide or from deposition of suspended matter in the hypolimnion water. We propose that the magnetic properties of surficial sediments are controlled by limnological stratification of the brackish lake water, thus possibly providing an analog for down-core variations of magnetic parameters associated with the modification of magnetic minerals during reductive diagenesis.

    DOI

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    6
    Citation
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  • Magnetic properties of surficial sediments in Lake Ogawara on the Pacific coast of northeastern Japan: spatial variability and correlation with brackish water stratification

    Akira Hayashida, Ryoma Nakano, Aya Nagashima, Koji Seto, Kazuyoshi Yamada, Hitoshi Yonenobu

    EARTH PLANETS AND SPACE   67  2015.10  [Refereed]

     View Summary

    To examine limnological conditions in Lake Ogawara on the Pacific coast of northwestern Japan, we investigated the magnetic properties of dredged bottom sediment originally collected from the lake in the summer of 2011. We used non-destructive methods to measure the low-field magnetic susceptibility shortly after sampling, and anhysteretic remanent magnetization (ARM) was assessed in 2012 and 2015. The ARM acquisition and demagnetization curves from littoral sites showed several patterns that reflect the provenance of the sediments. At water depths below 10 m, the magnetic susceptibility and ARM of greenish black mud with high organic content decreased considerably with the increase in water depth, but ARM increased slightly at water depths greater than 16 m. We also found that the magnetic concentrations of mud samples were reduced markedly during a period of storage for about 3 years. We attributed these reductions to diagenetic loss of magnetic minerals, which had been enhanced at deeper sites. It is possible that the ARM carriers in deeper areas were derived from authigenic formation of iron sulfide or from deposition of suspended matter in the hypolimnion water. We propose that the magnetic properties of surficial sediments are controlled by limnological stratification of the brackish lake water, thus possibly providing an analog for down-core variations of magnetic parameters associated with the modification of magnetic minerals during reductive diagenesis.

    DOI

    Scopus

    6
    Citation
    (Scopus)
  • The Holocene environmental changes in southern Indonesia reconstructed from highland caldera lake sediment in Bali Island

    Yu Fukumoto, Xun Li, Yoshinori Yasuda, Makoto Okamura, Kazuyoshi Yamada, Kaoru Kashima

    Quaternary International   374   15 - 33  2015.07  [Refereed]

     View Summary

    Diatom, pollen, geomagnetic and geochemical analyses were carried out on a 3.6m long sediment core taken from Lake Buyan, a highland caldera lake in central Bali Island, to reconstruct the Holocene climate changes in equatorial southern Indonesia. The core represents ~8 thousand years sedimentation of organic-diatomaceous lake mud. Constant inclusion of benthic diatom fossils as main components indicated that suspension and inflow of littoral materials were the main sedimentary process. The core contained laminated sediments in two distinct intervals at 6.5-5.0 and 3.6-3.1calkyBP, and multi-proxy records showed generally drier climate in these sections especially at 3.6-3.1calkyBP. Lake bottom waters were more reducing condition in these laminated periods probably due to increased lake productivity by prolonged dry season and wind mixing. Laminae structures were made up of a layer composed of benthic diatoms and amorphous organic materials, and a layer made by only planktonic diatom fossils, each of which may represent rainy and dry period deposits. Although southern Indonesia shows clear Australian monsoon rainfall seasonality at present, counting of layer numbers showed interannual cycles of laminae formation. Prolonged dry seasons could obscured the rainfall seasonality in these periods, but precise depositional patterns were elusive. Unlaminated sections showed homogeneous sediment mixture of benthic, planktonic diatoms and more volume of terrigenous materials indicating wetter climate and seasonality similar to the present time. This was supported by the higher share of marsh environment pollens reflecting more stable lake level trends. The dry climate from 6.5calky BP was in line with the general perception of stronger ENSO dynamics from the mid Holocene due to weaker than before boreal summer insolation, but the sporadic appearances of dry periods imply the influence of regional climate forcings such as temporal migrations of inter tropical convergence zone (ITCZ). It was, however, possible that temporal shifts of large climate mode occurred in equatorial Pacific and Indian Oceans. Wettest climate was inferred from 3.1calkyBP to the present and this might reflect increased importance of Austral hemisphere atmospheric convection and subsequent southerly position of ITCZ in Austral summer time.

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    6
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  • 琵琶湖愛知川沖ボーリング試料から推定される過去約4.5万年間の湖水位変動

    井内美郎, 山田和芳, 里口保文, 芳賀裕樹, 林竜馬

    Proc Symp Geo-Environ Geo-Tech   24th   127 - 128  2014.11

    J-GLOBAL

  • Human impact on the Kiso-hinoki cypress woodland in Japan: a history of exploitation and regeneration

    Junko Kitagawa, Toshiyoshi Fujiki, Kazuyoshi Yamada, Yasuharu Hoshino, Hitoshi Yonenobu, Yoshinori Yasuda

    Vegetation History and Archaeobotany   23 ( 6 ) 649 - 664  2014.08  [Refereed]

     View Summary

    The Kiso-hinoki (Kiso-Japanese cypress, Chamaecyparis obtusa) woodland underwent severe deforestation in the early 17th century, then regenerated through conservation during the Edo period. Now, a suitable management strategy is sought in order to maintain its ecological function in the forest. To understand the vegetation changes and human impact, sediment cores were recovered from Lake Tadachi in the Kiso-hinoki cypress woodland in the central uphill region of Honshu island. In addition, stratigraphic pollen analysis on two cores (Nos. 6 and 10) and phytolith analysis on three strata of one core (No. 6) was conducted. The age-depth models were constructed based on 14C dating, greyscale analysis on the sediments, and the increasing level of Cryptomeria pollen (about a.d. 1960) from the pollen profiles. In all periods, the dominant pollen taxa were Cupressaceae and Quercus subgen. Lepidobalanus type. Our analysis indicates that after the commencement of Shikinen-sengu, which is the rebuilding of the Ise Grand Shrine every 20 years, Cupressaceae pollen decreased and the woodland was gradually replaced by Quercus subgen. Lepidobalanus. The percentages of Cupressaceae pollen decreased dramatically and the expansion of secondary woodlands was accompanied by an increase of Quercus subgen. Lepidobalanus in the early 17th century cal. a.d. However, depletion of the woodland was determined from a decrease in concentration of Quercus pollen. The conservation activity during the Edo period and after the Meiji Restoration brought about woodland recovery. However, based on our pollen and phytolith analysis, significant changes to the woodland habitats can be detected. These were probably due to human impacts, most notably in the years after World War II. Four major turning points as the result of human influence were identified: the 10th century, the late 16th century, the Meiji restoration (a.d. 1863), and the end of World War II. The original cypress woodland mixed with deciduous broad-leaved elements has been greatly reduced, preventing future cypress woodland regeneration after World War II.

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  • Climate changes for the past 52 ka clarified by total organic carbon concentrations and pollen composition in Lake Biwa, Japan

    Tomohiko Kigoshi, Fujio Kumon, Ryoma Hayashi, Manato Kuriyama, Kazuyoshi Yamada, Keiji Takemura

    Quaternary International   333   2 - 12  2014.05  [Refereed]

     View Summary

    Total organic carbon (TOC) and total nitrogen (TN) analyses have been performed for three core samples obtained recently from Lake Biwa, which include BIW07-5, BIW07-6, and BIW08-B cores. The TOC and TN data from these cores show similar stratigraphic changes and can be regarded as reliable records of biological productivity occurring in the lake during the past 52 ka. Pollen analysis data are also used to determine climate change during the past 40 ka by reconstructing meteorological parameters such as annual temperature and precipitation. Temporal changes in TOC concentration show detailed climate changes in tens-year intervals. Climate change of orbital scale are well recognized, demonstrating the change from MIS 3 to 1 associated with severe cold periods known as Heinrich events 1 to 5 and warm periods known as Greenland interstadials (GIS 1-13). These climate events in millennial time scale are also well supported by pollen characteristics and by modern analogue analysis. The good concordance of climate change between North Atlantic region and Japan is explained by a hypothesis that the intensity of the Arctic air mass controls the climate in both the North Atlantic and East Asia regions through the migration of the Arctic polar front. Although the average annual mean temperature in MIS 3 was 8.2 ± 0.8 (2. σ) °C, it varied largely and frequently among its substages. For example, 9.4 ± 2.0 °C was detected in a warm interstadial (GIS 8), and 6.3 ± 1.5 °C indicated in a cold stadial (Heinrich event 4). The average annual temperature was 4.5 ± 0.3 °C in MIS 2, when the average temperature of the coldest month was -7.3 ± 0.2 °C and that of the warmest month was 16.8 ± 0.2 °C. Through Termination 1, the annual mean temperature suddenly increased more than 5 °C, and the annual mean temperature became 11.2 ± 0.8 °C in early MIS 1, which is much lower than that of the present temperature. This low temperature estimation is attributed to the delay in expansion of evergreen broadleaf trees. The annual mean temperature in the late MIS 1 was as same as that of present meteorological observation. © 2014 Elsevier Ltd and INQUA.

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  • 第四紀研究における年代測定法の新展開―最近10年間の進展―年縞編年学の進歩

    山田和芳, 五反田克也, 篠塚良嗣, 斎藤めぐみ, 藤木利之, 瀬戸浩二, 原口強, 奥野充, 米延仁志, 安田喜憲

    月刊地球     25 - 30  2014.02

    J-GLOBAL

  • Paleoenvironment of Matsue plane, Shimane prefecture, southwest Japan (2)

    SETO Koji, WATANABE Masami, YAMADA Kazuyoshi, TAKAYASU Katsumi

    Annual Meeting of the Geological Society of Japan   2014 ( 0 ) 317 - 317  2014

    DOI CiNii

  • Investigaciones Arqueologicas y Paleoambientales en y alrededor de Ceibal, Peten, Guatemala

    Aoyama, Kazuo, Hitoshi Yonenobu, Takeshi Inomata, Kazuyoshi Yamada, Hiroo Nasu, Toshiyuki Fujiki, Yoshitsugu Shinozuka, Katsuya Gotanda, Yoshiharu Hoshino

    XXVII Simposio de Investigaciones Arqueologicas en Guatemala     987 - 995  2014  [Invited]

  • 琵琶湖高島沖ボーリングコア中の過去約13万年間の生物源シリカ含有率から見た古気候変遷

    村越貴之, 根上裕成, 山田和芳, 井内美郎

    Proc Symp Geo-Environ Geo-Tech   23rd   207 - 212  2013.11

    J-GLOBAL

  • 過去約4.5万年間の琵琶湖古水位変動

    井内美郎, 山田和芳, 岡村眞, 松岡裕美, 里口保文, 芳賀裕樹, 林竜馬, 根上裕成, 村越貴之

    Proc Symp Geo-Environ Geo-Tech   23rd   213 - 218  2013.11

    J-GLOBAL

  • 島根県宍道湖湖底堆積物に記録された完新世中期以降の冬季アジアモンスーン変動

    山田和芳, 高安克己

    Proc Symp Geo-Environ Geo-Tech   23rd   219 - 224  2013.11

    J-GLOBAL

  • An Assessment of the Magnitude of the AD1586 Tensho Tsunami Inferred from Lake Suigetsu Sediment Cores

    齋藤めぐみ, 山田和芳, STAFF Richard A, 中川毅, 米延仁志, 原口強, 竹村恵二, BRONK RAMSEY Christopher

    地学雑誌   122 ( 3 ) 493 - 501  2013.06

     View Summary

    Sediment cores from Lake Suigetsu, Japan, reveal the absence of seawater intrusion into the lake caused by the historically documented tsunami of AD1586 (Tensho Tsunami). A high-precision chronology of the cores established by Bayesian modeling radiocarbon determinations enables us to ascertain the precise position of the historical event in the sediment depth. Diatom analysis of the core shows that a diatom assemblage dominated by freshwater taxa persisted through the period. This makes a clear contrast with the core section around AD1664 when the lake was artificially connected to the sea by a channel, and the subsequent intrusion of seawater was clearly recorded in the sediment cores by the occurrence of marine diatom fossils.

    DOI CiNii J-GLOBAL

  • Reconstruction of an 8,000-year environmental history on pollen records from lake buyan, central bali

    Xun Li, Yoshinori Yasuda, Toshiyuki Fujiki, Makoto Okamura, Hiromi Matsuoka, Kazuyoshi Yamada, John Flenley

    Advances in Asian Human-Environmental Research   ( 9784431541103 ) 407 - 426  2013

     View Summary

    New evidence from Lake Buyan, a 65-m-deep caldera lake in central Bali, presents an 8,000-year record of vegetation and climate change through palynological and physio-geochemical analyses. The distinct sediment phases associated with relative vegetation fluctuations and change of physio-geochemical index suggest that Bali might have experienced cycles of wet and dry climate change over 8,000 years. Vegetation composed of marshland/gap-colonizers, being coeval with the intensive process of erosion as indicated by an increased input of minerogenic material from the catchment, characterizes the periods when homogeneous lake mud sediments are formed, indicating relatively higher rainfall at period of 8.0–6.6 ka BP, 5.1–3.6 ka BP and 2.8 ka BP to present. At the time when laminated lake sediments commence, e.g., 6.6–5.1 ka BP and 3.6–2.8 ka BP, vegetation of a rather dry and fire-resistant character dominates, in concomitant with lower input of minerogenic material and suggests drier episodes. Regional comparison indicates that human-induced vegetation destruction is insignificant in Bali, except that cultivation activities might have been manifested in the recent 3,000 years, and the climatic variability observed from this core was probably El Niño Southern Oscillation (ENSO)-related.

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  • Climate deterioration and angkor’s demise

    Yoshinori Yasuda, Hiroo Nasu, Toshiyuki Fujiki, Kazuyoshi Yamada, Junko Kitagawa, Katsuya Gotanda, Shuichi Toyama, Mitsuru Okuno, Yuichi Mori

    Advances in Asian Human-Environmental Research   ( 9784431541103 ) 331 - 362  2013

     View Summary

    Reconstruction of the paleoclimate based on analyses of annually laminated sediments in Japan and moat sediments from Angkor Thom in Cambodia indicates that there had been a period of drastic cooling during AD 1430–1500 accompanied by a weakening of monsoon activity. The annual mean temperatures show that—compared to the peak of medieval warm epoch around AD 1150—the mean temperature dropped by nearly 5°C in AD 1430. The climatic cooling brought about the weakening of the summer monsoon, which in turn would have resulted in the delayed arrival of the wet season. This might have had a catastrophic impact on rice cultivation in Cambodia leading to the decline of the Khmer Civilization.

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  • 第四紀研究における年代測定法の新展開;最近10年間の進展−(I)放射性炭素年代−

    奥野 充, 山田和芳, 下岡順直, 編

    月刊地球   35 ( 35 ) 491 - 568  2013

    CiNii

  • The Pan Pacific life civilization

    安田喜憲, 米延仁志, 山田和芳, 那須浩郎, 篠塚良嗣, 森勇一, HOOGHIEMSTRA H

    第四紀研究   51 ( 4 ) 285 - 294  2012.08

     View Summary

    This paper proposes the existence of a Pan Pacific life civilization. Conventional concepts in the study of civilization have all been modeled on civilization developed by a wheat-cultivating pastoral culture in which the main diet consists of bread, milk, and meat. The Mesopotamia, Indus River, Egypt, and Yellow River civilizations have all risen from societies that keep either sheep and goats as livestock and consume their milk and meat.<BR>However, a completely distinct type of civilization has existed in the Pan Pacific region, of which the Yangtze River, Maya, and Andes civilizations are the prime examples. The Yangtze River civilization was a rice-cultivating piscatory culture with a diet composed mainly of rice and fish and devoid of milk from livestock such as sheep and goats.<BR>The staple foods of the Maya and the Andes civilizations were potatoes and corn, and although their diet included the meat of llama and alpaca, milk from these animals was not consumed. The Pan Pacific life civilization lacked sheep and goats, so its impact on ecosystems was small. The Pan Pacific life civilization was a milkless civilization and respected life and worshipped nature, preserving the circulation of forest and water.

    DOI CiNii J-GLOBAL

  • 地学系専門学協会による一般市民を対象としたアウトリーチ巡検の実践報告

    植木岳雪, 中尾賢一, 西山賢一, 森江孝志, 竹村恵二, 米延仁志, 山田和芳, 長谷川修一

    地学教育   65 ( 2 ) 63 - 80  2012.03

    CiNii J-GLOBAL

  • The structure and significance of early Holocene laminated lake sediments in the Faiyum Depression (Egypt) with special reference to diatoms

    R. J. Flower, K. Keatings, M. Hamdan, F. A. Hassan, J. F. Boyle, K. Yamada, Y. Yasuda

    Diatom Research   27 ( 3 ) 127 - 140  2012

     View Summary

    Lake Qarun lies in the Egyptian Faiyum Depression and is the modern remnant of a much larger Holocene lake. Variations in water level occurred during the Holocene as a result of palaeoclimate changes and, since ca. 4000 bp, there have been hydrological interventions. Past lake levels have been inferred from the locations of archaeological sites, former beaches and exposed lake sediments, but there is no continuous Holocene palaeolimnogical record for the lake. To explore the potential of this record, three sediment cores (10.4-21.4m long) were collected from terrestrial locations on the southern margin of the lake in 2008. The basal sections of all three cores consisted of thinly laminated diatom marl sediments overlying coarse sand. The nature of these laminations was investigated in thin sections from two cores (QARU9 and 10). Quantitative very high-resolution diatom analysis revealed seasonal succession patterns of Aulacoseira and Stephanodiscus species within diatom-rich laminae. Elemental microprobe analysis of one thin section (QARU10) confirmed the presence of alternating Ca- and Si-rich laminae. The results indicate annually deposited sediment sequences with seasonality signals provided by microlayers of diatoms, calcite and clastic material. According to diatom counting, mean varve thicknesses equated to 6.0 (QARU9) and 9.4 (QARU10) annual diatom laminae accumulated cm?1. Radiocarbon dates from a third core (adjacent to QARU9) indicated that the QARU9 thin section material was bracketed between 8693 and 9935 cal bp. Diatom microstratigraphy was used to infer seasonality in varve forming processes. Gross sediment stratigraphy indicated that varve forming conditions had persisted for >1500 years. The presence of early Holocene varved sediments in palaeo-Lake Qarun provides an exceptional palaeoenvironmental archive for northeast Africa. © 2012 The International Society for Diatom Research.

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  • Rapid prediction of past climate condition from lake sediments by near-infrared (NIR) spectroscopy

    Tetsuya Inagaki, Yoshitsugu Shinozuka, Kazuyoshi Yamada, Hitoshi Yonenobu, Akira Hayashida, Satoru Tsuchikawa, Akihiro Yoshida, Yasuharu Hoshino, Katsuya Gotanda, Yoshinori Yasuda

    Applied Spectroscopy   66 ( 6 ) 673 - 679  2012  [Refereed]

     View Summary

    This study explored the feasibility of rapid, nondestructive near-infrared (NIR) reflection spectroscopy for the prediction of conventional physical properties, carbon-nitrogen-sulfur (CNS) analysis, and concentration of inorganic components in sediment cores from a brackish lake. A long core sample, which consisted of well-preserved annually formed lamina from Lake Ogawara along the Pacific coast in Aomori Prefecture, northeastern Japan, was used to investigate the past environmental record. The core was previously analyzed for physical properties, CNS, and inorganic components. Calibration models were developed from NIR reflection spectra of 149 core samples. Partial least squares (PLS) analysis provided good regression models between measured and predicted values for water content, total nitrogen (TN), total organic carbon (TOC), total sulfur (TS), Al 2O 3, S/Al 2O 3, Fe 2O 3/Al 2O 3, Sc/Al 2O 3, Cu/Al 2O 3, and Zn/Al 2O 3 with coefficients of determination (r 2) for cross-validation of 0.73, 0.89, 0.88, 0.73, 0.92, 0.81, 0.82, 0.75, 0.82, and 0.82, respectively. The variation of predicted component values as a function of depth showed the same trend as that of conventionally measured values. This study also showed the possibility of NIR spectroscopy as an on-site, rapid analytical tool for the identification of tephra (fragmental material produced by a volcanic eruption regardless of composition, fragment size, or emplacement mechanism), which is important for dating. © 2012 Society for Applied Spectroscopy.

    DOI PubMed

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  • Widespread tephras in sediments from lake Ichi-no-Megata in northern Japan: Their description, correlation and significance

    Mitsuru Okuno, Masayuki Torii, Kazuyoshi Yamada, Yoshitsugu Shinozuka, Tohru Danhara, Katsuya Gotanda, Hitoshi Yonenobu, Yoshinori Yasuda

    Quaternary International   246 ( 1-2 ) 270 - 277  2011.12  [Refereed]

     View Summary

    Lake Ichi-no-Megata is a maar in the Oga Peninsula, which is connected with the western side of Honshu Island, NE Japan. A 37-m long sediment core (IMG06) obtained from the center of the lake contains five fine ash layers. Stratigraphic positions in the core provide ages of five ashes to be 30, 21, 17, 7.3, and 1.0 cal ka BP, respectively. These layers are correlated with Aira-Tn (AT), Daisen-Kusatanihara (D-KsP), Asama-Kusatsu (As-K), Kikai-Akahoya (K-Ah) and Baitoushan-Tomakomai (B-Tm) tephras in ascending order, based on stratigraphy and petrographic characteristics such as grain assemblages, refractive indices, and major element compositions of glass shards. Although the AT, K-Ah and B-Tm tephras have been well known as widespread tephras, this study finds that the D-KsP, As-K and K-Ah tephras have more extensive distributions than the previous studies estimated. The D-KsP and As-K tephras have the potential to become useful time-markers in and around the Sea of Japan between the AT and K-Ah tephras. © 2011 Elsevier Ltd and INQUA.

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  • The formation process of Izumo plain and paleoenvironmental changes based on boring core obtained from Izumo district, western Japan.

    Okazaki Yuko, Seto Koji, Takata Hiroyuki, Sakai Tetsuya, Ooki Ayaka, Yamada Kazuyosi, Nasu Hiroo, Watanabe Masami

    Annual Meeting of the Geological Society of Japan   2011 ( 0 ) 49 - 49  2011

    DOI CiNii

  • 白頭山の10世紀噴火についての最近の年代研究(レビュー)

    奥野 充, 八塚槙也, 中村俊夫, 木村勝彦, 山田和芳, 齋藤めぐみ, 谷口宏充

    東北大学東北アジア研究センター叢書   41   103 - 111  2010.12

    CiNii

  • 男鹿半島,二ノ目潟・三ノ目潟湖底堆積物の年縞構造と白頭山-苫小牧火山灰(B-Tm)の降灰年代

    上手真基, 山田和芳, 齋藤めぐみ, 奥野 充, 安田喜憲

    地質学雑誌   116 ( 7 ) 349 - 359  2010.07  [Refereed]

     View Summary

    This paper presents the results of microscopic observations of thin sections of sediment cores from Lakes Ni-no-Megata and San-no-Megata, Oga Peninsula, NE Japan. Micro-sedimentary structures indicate that cycles of light-dark lamina couplets represent biogenic varves, marking annual laminations. We identified 14 complete annual cycles and 1 partial annual cycle between the thin tephra layers of Towada-a (To-a) and Baitoushan-Tomakomai (B-Tm) in sediment cores from the two lakes, suggesting that B-Tm was deposited in AD 929. We also determined that To-a was deposited during early spring, while B-Tm was deposited during one or more eruption events during spring-summer.

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  • Late Holocene monsoonal-climate change inferred from Lakes Ni-no-Megata and San-no-Megata, northeastern Japan

    Kazuyoshi Yamada, Masaki Kamite, Megumi Saito-Kato, Mitsuru Okuno, Yoshitsugu Shinozuka, Yoshinori Yasuda

    Quaternary International   220 ( 1-2 ) 122 - 132  2010.06  [Refereed]

     View Summary

    Micro-sedimentological, geochemical data from Lakes Ni-no-Megata and San-no-Megata in northeastern Japan are used to reconstruct environmental and climate changes over the last 2000 years. Comparing these records in two neighboring maar lakes allows reconstruction of centennial scale climate change concerned the East Asian monsoon activities without the influence of human activities. S content and coarse mineral grains records show that long-term climate changes, with one warm/humid interval from AD 1200 to 750, and two cold/dry intervals from AD 1 to 750, AD 1200 to the present. These climate changes have similar trends to Asian monsoon records in China, and could correspond to the Dark Age Cold Period (DACP), the Medieval Warm Period (MWP) and the Little Ice Age (LIA) climate changes in Europe. Moreover, short-term climatic deterioration events occurred in the 6th, 10th and 18th centuries. Particularly the event around the 10th century is well correlated with other paleoclimate proxies in China, Europe and Mesoamerica, suggesting tele-connection by atmospheric circulation through the Northern Hemisphere. However, the record is asynchronous with solar activity. This might suggest the solar forcing has indirectly influenced lake sedimentation associated with Asian monsoon activities in Japan. © 2009 Elsevier Ltd and INQUA.

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  • Eutrophication-induced changes in Lake Nakaumi, southwest Japan

    Kota Katsuki, Yasushi Miyamoto, Kazuyoshi Yamada, Hiroyuki Takata, Keiko Yamaguchi, Daisuke Nakayama, Hugo Coops, Hidenobu Kunii, Ritsuo Nomura, Boo Keun Khim

    Journal of Paleolimnology   40 ( 4 ) 1115 - 1125  2008.11  [Refereed]

     View Summary

    Lake Nakaumi, southwest Japan, is an enclosed lagoon characterized by polyhaline and halocline conditions. Since the last century, its ecological state has been altered by eutrophication. We used a paleolimnological approach and studied multiple proxies, including chemical compounds, diatoms, foraminifera and molluscs, to infer the eutrophication history of the ecosystem. Eutrophication in Lake Nakaumi was associated with several factors, including increased nutrient loading, input of herbicides, and dike building since the 1920s. The ecological condition of this lake was divided into several stages that reflect the eutrophication process after the 1940s. A catastrophic "regime shift" from a clear state with aquatic vegetation to a turbid one with phytoplankton occurred in the early 1950s. Environmental degradation in the Honjo area, a part of Lake Nakaumi, was attributed primarily to physical changes caused by the construction of an enclosing dike. Eutrophication occurred almost simultaneously with the physical changes to the Honjo area in the 1970s. Until recently, no regime shift was observed in this area, though the core-top sediments show possible symptoms of incipient change. © 2008 Springer Science+Business Media B.V.

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  • Fossil benthic foraminifera from sediment core S1 of Lake Shinji, western Japan

    Takata Hiroyuki, Yamada Kazuyoshi, Katsuki Kota

    Laguna   14 ( 14 ) 1 - 7  2007.12

     View Summary

    Fossil benthic foraminifera from a sediment core taken from central Lake Shinji, western Japan, were investigated as an indicator of paleoenvironmental change in the Shinjiko-Nakaumi lake system during the 20th century. A transition from dominance of Haplophragmoides canariensis to that of Ammonia beccarii forma 1 occurred in the middle 20th century. This faunal association and its transition are similar to those observed in previous studies of Lake Shinji and the Ohashi River. This faunal transition might be affected by not only environmental change in Lake Shinji but also that in the Ohashi River.

    CiNii

  • 地質コア解析に基づいた出雲平野の形成史

    山田 和芳

    島根県古代文化センター調査研究報告 35     110 - 127  2007

  • 20世紀における中海の汚濁化:文献資料と底質コア試料の分析結果

    宮本 康, 山田 和芳, 高田 裕行, 中山 大介, 山口 啓子, 香月 興太, Coops Hugo, 國井 秀伸

    日本陸水学会 講演要旨集   72   52 - 52  2007

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  • High-resolution past environmental reconstruction in East Asia using annually laminated lake sediments of Lake Megata in northeastern Japan

    Yamada K, Gotanda K, Yonenobu H, Shinozuka Y, Kitagawa J, Makohonienko M, Schwab M, Haraguchi T, Yasuda Y

    AGU Fall Meeting Abstracts    2007  [Refereed]

  • A report on the ESF-JSPS Frontier Science Conference Series for Young Researchers 2006 : Climate Change

    AKIYAMA Hiroko, ARIMOTO Masahiro, UEMURA Ryu, O'ISHI Ryouta, ZAIKI Masumi, SATO Tomonori, DAIRAKU Koji, TAGUCHI Masakazu, TOZUKA Tomoki, TOYODA Takahiro, NAGASHIMA Kana, NAGANO Takanori, NISHIZAWA Seiya, NISHIDA Satoshi, HORI Masatake, MIYOSHI Takemasa, YASUNAKA Sayaka, YAMAGUCHI Kosei, YAMADA Kazuyoshi, YOSHIKAWA Chisato, WATANABE Eiji

    天気   53 ( 12 ) 913 - 918  2006.12

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  • Imaging of spin density distribution by magnetic structure analysis in Nd2 CuO4

    Hiroyuki Kimura, Kohei Kadoshita, Yukio Noda, Kazuyoshi Yamada

    Physica B: Condensed Matter   385-386   133 - 136  2006.11  [Refereed]

     View Summary

    Crystal- and magnetic-structure analyses for a single crystal of Nd2 CuO4 (NCO) have been carried out to visualize the spin density distribution on 3d-electron orbital for Cu2 + ion. NCO is an antiferromagnet with 3 d9 electronic configuration in Cu2 + ion, where S = 1 / 2 spin localizes on dx2 - y2 orbital. Spin density distribution ρ (r) of Cu2 + spin in NCO, which is directly obtained by three-dimensional Fourier synthesis of magnetic form factor f (Q), quite well agree with the calculated value of ρ (r) for 3d-electron on dx2 - y2 orbital. The present results demonstrated that our method is of great use for imaging the electron orbital, and is applicable to various system where the orbital degree of freedom contributes to their physical properties. © 2006 Elsevier B.V. All rights reserved.

    DOI

  • The Holocene Paleoenvironmental Change in the Coastal Lagoon : The Environmental Change by Nature and Artifical Modifications

    SETO K., YAMADA K., TAKATA H., SAKAI S.

    第四紀研究 = The Quaternary research   45 ( 5 ) 315 - 316  2006.10

    CiNii

  • Paleoenvironmental Variability during the Holocene in the Area of Izumo Plain-Lake Shinji Based on the Results of Sedimentary Cores

    YAMADA Kazuyoshi, TAKAYASU Katsumi

    The Quaternary research   45 ( 5 ) 391 - 405  2006.10

    DOI CiNii

  • Significant Tsushima Warm Current during the Early-Middle Holocene along the San-in District Coast Inferred from Foraminiferal Profiles

    TAKATA Hiroyuki, ITAKI Takuya, IKEHARA Ken, YAMADA Kazuyoshi, TAKAYASU Katsumi

    The Quaternary Research (Daiyonki-Kenkyu)   45 ( 3 ) 249 - 256  2006.06

     View Summary

    Planktonic foraminifera in cores HS02 (northwestern Izumo Plain) and GH87-2-308 (off Tottori) were used to document the occurrence of warm-water fauna and infer the presence of the Tsushima Warm Current in the coastal region of the southern Sea of Japan during the Early-Middle Holocene. Based on the downcore distribution of Globigerinoides ruber, a warm-water planktonic foraminifer, in core GH87-2-308, the influence of the Tsushima Warm Current was significant at ca. 8.3&mdash;8.0 and ca. 7.3&mdash;6.8ka. This species is also found at the &sim;7.8ka level in core HS02, showing the presence of a warm-water benthic fauna in &ldquo;Paleo-Shinji Bay.&rdquo; According to previous floral and faunal studies in the hemi-pelagic region (e.g. Oki Ridge) of the Sea of Japan, warm-water taxa were common around ca. 7.3ka, but were not common during the 8.3&mdash;7.8ka interval. It is suggested that the influence of the Tsushima Warm Current was significant along the San-in District coast at ca. 8.3&mdash;7.8ka, and it contributed to the occurrence of warm-water faunas in this area, including &ldquo;Paleo-Shinji Bay.&rdquo;

    DOI CiNii

  • The linkage of Asian monsoon activities and glacial-interglacial cycles recorded in loess and lacustrine deposits

    YAMADA Kazuyoshi, FUKUSAWA Hitoshi

    The Journal of the Geological Society of Japan   111 ( 11 ) 679 - 692  2005.11

     View Summary

    In this paper, we reviewed and discussed the recent progress and perspectives mentioned in the research of paleo Asian monsoon activities from the records of loess-paleosol sequences and lacustrine sediments in East Asia. Loess-paleosol sequences and lacustrine sediments in East Asia have been recorded terrestrial environmental changes associated with East Asian monsoon activities since the beginning of Quaternary. The researches to reconstruct the activities of paleo East Asian monsoon started in 1982 by Heller and Liu (1982), and has been stored much information on the formation and variability of the monsoon in the last two decades. Onset of loess deposition might begin in 2.6 Ma, and after that the fluctuations of the monsoon activities have been reflected the glacial-interglacial cycles controlled by the Milankovitch forcing. Also, the millennial time-scale variation of the monsoon activities can be recognized in the last glacial time. The recent research on Red Clay underlying the loess-paleosol sequence may point out that the formation of the monsoon activities dates back to 7 or 8 Ma.<br>

    DOI CiNii

  • タイ南部ソンクラー湖における汽水域の形成環境と近年の地球温暖化との関係の解明 (平成16年度研究助成成果報告 地理)

    山田 和芳

    財団法人福武学術文化振興財団歴史学・地理学助成報告書   2005   138 - 146  2005

    CiNii

  • Holocene paleoenvironmental changes recorded in lacustrine sediments of Lake Jinzai, Shimane Prefecture, western Japan

    YAMADA K., Takata Hiroyuki, Takayasu Katsumi

    Laguna   11 ( 11 ) 135 - 145  2004.06

     View Summary

    Lake Jinzai is a small brackish water lake located in the southwestern part of the Izumo Plain, Shimane Prefecture, western Japan. The JZ-01 sediment core was taken at the center of the lake(35°19′N, 132°41′E; water depth 1.55 m)using a thin-wall type piston core sampler. The core length is 24.3 m. This study clarified the stratigraphy and sedimentation rates in the JZ-01 core on the basis of an initial core description and eleven AMS radiocarbon dates of organic material and shell fragments. This study also reconstructs high resolution Holocene environmental change from the mineralogy and chemical composition of the core sediments. The variability in Lake Jinzai water conditions is apparent in the content of authigenic iron minerals(pyrite, marcasite and siderite)and the sulfur content of the sediment. These results demonstrate that lake water conditions changed drastically throughout the Holocene, with brackish water intervals from 9,500 to 7,300, 4,100 to 1,900 and from 400 cal. yr B.P. to the present. Also the influence of human activity on the lake environment began around 2,000 cal. yr B.P. - a time which may be related to a significant increase in the number and size of archaeological sites of the Ancient Izumo Kingdom.

    CiNii

  • Paleo Asian monsoon activities fluctuation since the last interglacial stages detected by lacustrine sediments of Lake Erhai, Yunnan Province, China

    YAMADA Kazuyoshi, FUKUSAWA Hitoshi, OKUNO Mitsuru

    Annual Meeting of the Geological Society of Japan   2003   207 - 207  2003

    DOI CiNii

  • Environmental Change and Rise and Fall of the Civilizations in Monsoon Asia

    YASUDA Yoshinori, FUKUSAWA Hitoshi, GOTANDA Katsuya, NAKAGAWA Takashi, TARASSOV Pavel E., NISHIDA Kotoba, KATO Megumi, SAWAI Yuki, MOMOHARA Arata, FUJIKI Toshiyuki, NASU Hiroo, KITAGAWA Junko, YAMADA Kazuyoshi, KOROGI Chiharu, OKUNO Mitsuru, IWATA Shuji, ZHOU Zhekun, NARUSE Toshiro, YATAGAI Shinichi, KOBAYASHI Manabu, TAKAHASHI Manabu, KAWASUMI Tatsunori, MORITA Yoshimune, KURODA Tomio, YANO Azusa, SATO Yo-Ichiro, MORI Yuichi, KANEHARA Masaaki, MOTOKI Yasushi

    Geographical review of Japan series A   75 ( 5 ) 384 - 390  2002

    DOI CiNii

  • Pollen Analytical Study of the Sediments from the Institute for Nature Study (II)

    Yasuda Yoshinori, Fukusawa Hitoshi, Fujiki Toshiyuki, Nakagawa Takeshi, Yamaguchi Kentaro, Gotanda Katsuya, Yamada Kazuyoshi, Inoue Yasushi, Urasaki Yasuhiro

    Miscellaneous reports of the Institute for Nature Study   33 ( 33 ) 445 - 459  2001.12

    CiNii

  • High-resolution Multi-proxy Records of Asian Monsoon Activities from Sediments over Last 75,000 Years

    FUKUSAWA Hitoshi, YAMADA Kazuyoshi

    Journal of geography   107 ( 4 ) 566 - 571  1998.08

    DOI CiNii

  • Recent Progress on Collecting and Analyzing Methods of Brackish Lake Sediments

    Yamada Kazuyoshi, Saito Koji, Fukusawa Hitoshi

    Laguna   5 ( 5 ) 63 - 73  1998.03

     View Summary

    Recent studies on ice cores and deep sea sediments have revealed that abrupt and rapid climate and sea-level changes occurred frequently durmg the Late Quaternary. The brackish lake sediments which represent non-glacial varve layers record the detailed environmental changes, however, it has been difficult to detect such rapid changes from lake sediment cores. One of the reason of the difficulty is the lack of the method for collecting intact sediments for systematic ana1ysis. Here we present our systematic research procedure with improved efficiency,which includes an improved coring device for obtaining intact brackish lake sediments,initial description, sampling, and several analytical methods. This enables us to detect environmental variations on annual to decadal time scale.人類が急速に進化した時代である第四紀には,数~十万年スケールの氷期一間氷期サイクルにともなう,自然環境の変動が生じていたと考えられてきた(成瀬,1982)。しかし,近年グリーンランドの氷床堆積物や北大西洋や日本海の海底堆積物および中国内部の陸上堆積物の研究から,約1000~3000年周期で気侯や海水準が突然かつ急激に変動することが知られるようになってきた(Dansgaard et al.,1993;Bond et al.,1997;Chen et al.,1997;多田,1997)。このような急激な環境変動は,過去の人類活動に大きな影響を与えてきたと思われる。海陸境界に位置する汽水湖沼は,さまざまな環境変動を堆積物に記録している。たとえば,福澤(1995)は,水月湖湖底堆積物の明暗ラミナの互層が1年ごとに形成された「年縞」であり,さらに湖底堆積物は天然の寒暖計,検潮儀,雨量計,地震計などの環境変動検出計でもあることを明らかにしている。また,湖沼堆積物の堆積速度は海洋堆積物と比較すると大きいことからも,汽水湖底堆積物を分析することによって,さまざまな環境変動を高時間分解能で復元できると考えられる。しかしながら,湖沼堆積物コアの従来の研究からは,短い時問スケールの急激な環境変動を捉えることができなかった。その原因として,堆積物の記載を含む採取・分析方法に問題があったと考えられる。堆積物の採取や試料の分割・分析には多くの時間と労力が費やされる。琵琶湖深層掘削研究の例が典型的である。世界に先駆けて行われた琵琶湖の湖底掘削では,有機・無機地球化学,微化石,火山灰などの総合的な研究がなされ,気侯変動や古地磁気変化などに関する多くの情報が明らかにされた(Horie,1984)。しかし,堆積物の欠層や分析試料の時間分解能の低さ,分析機器の測定誤差などのために,この研究成果がまとめられるまでには多くの時間と労力が費やされたばかりでなく、数千年単位の自然環境変動を検出することはできなかった。これらのことから,短い時間スケールの急激な環境変動を湖沼堆積物から検出するためには,より効率的な精度のよい堆積物の採取・記載・分析が必要となる。近年,地球環境の将来予測が重要視されてきている。その将来を知るためには過去を知らなければならず,そのためにもわれわれは,地球環境の変化してきた過程を総合的に明らかにしなければならない。すなわち,汽水湖底堆積物をこれまでよりも効率的に精度よく採取・分析することは,われわれ人類が将来歩む道を考えるうえで非常に重要であるといえる。われわれの研究グループは,季節単位あるいは1年単位で過去の環境変動を記録している堆積物を欠層なく連続的に採取して,年単位の気候・海水準変動を明らかにしてきた。この論文では,われわれの研究グループで行っている堆積物の採取・分析方法を,堆積物から得られる情報について,その意味する堆積機構や環境の変遷に言及しながら紹介する。

    CiNii

  • 湖沼堆積物による過去2,000年間の気候・海水準・大気変動の復元と未来予測

    福沢 仁之, 岩田 修二, 山田 和芳

    日産科学振興財団研究報告書   ( 21 ) 21 - 24  1998

    CiNii

  • Last 2.4 Ma Changes of Atomospheric Circulation along the Japan Sea-Chinese Loess Plateau-The Mediterranean Sea Transect caused by uplift of the Himalayan-Tibetan Plateau

    FUKUSAWA Hitoshi, OI Keiichi, YAMADA Kazuyoshi, IWATA Shuji, TORII Masayuki

    Journal of Geography (Chigaku Zasshi)   106 ( 2 ) 240 - 248  1997.04

     View Summary

    Recent atmospheric circulations over the Asian Continent have been influenced by the Himalayan Range and the Tibetan Plateau as a wind barrier. Based on recent meteorological data, the existence of the Himalaya-Tibet within the troposphere has caused meandering of the Westerlies, intense activity of the Asian Monsoon and appearance of the Easterlies. Meandering of the Westerlies has led to increase precipitation in the East Asia region including northeastern China and Japan, and has formed the soils with poorly crystalized illite minerals in the Chinese Loess Plateau and the Japanese Islands. In nothern India and Nepal including the frontal basin of the Himalayan Range such as the Kathmandu Basin, intense activity of the Asian Monsoon has led abruptly to increase precipitation named &ldquo;onset of monsoon&rdquo;. Also, appearance of the Easterlies from the Himalaya-Tibet to northern Africa within the upper part of the troposphere has led to dry and spread the arid area in the northern Africa.<BR>There are many sedimentary records indicating Late Quaternary climatic changes around the Himalayan-Tibetan Plateau. We expected to determine the formation age of recent atmospheric circulation. This age indicates when the Himalayan-Tibetan Plateau was abruptly uplifted and elevated. In other words, formation ages of more humid climate in northeastern China, the Japanese Islands and the Kathmandu Basin, and the driest climate in the northern Africa are useful to determine age of uplift and elevation of the Himalayan-Tibetan Plateau.<BR>On the base of above-mentioned evidences and hypothesis, we attempted to investigate magnetic susceptibility of the loess-paleosol sequence in the Luochuan area of th e northeastern China, and illite crystallinity of loess-paleosol sequence in the Kathmandu Basi n and deep-sea sediments of the Japan Sea and the Mediterrannean Sea. Because characteristic changes of magnetic susceptibility and illite crystallinity indicate dry -wet oscillations as useful detectors.<BR>As results, we clarified three evidences as follows:<BR>1) Large amplitudes of magnetic susceptibility oscillations by large pricipitation in interglacial periods appeared in the Luochuan loess -paleosol sequence during last 600ka.<BR>2) Large amplitudes of illite crystallinity oscillations by large precipitations caused decomposition of illite minerals appeared in the deep-sea sediments of the Sea of Japan during the last 800ka and in the loess-paleosol sequence of the Kathmandu Basi n during the last 1.1Ma. 3) Amplitudes of illite crystallinity oscillation during the last 800k a were smaller than those amplitudes since 800ka ago.<BR>Investigation mentioned above indicates that critical uplift and elevations of the Himalayan-Tibetan Plateau achieved to induce activity of westerlies, easterlies and the Asian Monsoon, and suggests that determined ages of critical elevation caused atmospheric circulation changes range from 0.6 million years to 1.1 million years ago.

    DOI CiNii

  • Climatic Changes Recorded in the Deep Sea Sediments (ODP Site 974B) of the Mediterranean Sea during the Last 4.5 Ma

    YAMADA Kazuyoshi, FUKUSAWA Hitoshi, ODP Leg 161 Shipboard, Scientific Party

    Journal of geography   106 ( 2 ) 218 - 225  1997

     View Summary

    We attempted to clarify changes of magnetic susceptibility and clay mineralogy of the deep-sea sediments in ODP site 974B during the last 4.5 Ma. These sediments are composed mainly of calcareous nannoplankton ooze with organic matters and eolian dusts. Sequential changes of illite crystallinity, expressing as full width of half maximun of 10 A peaks by X-ray diffraction patterns, indicate changes of dry-wet climatic conditions in a supply area.<BR>Due to the atmospheric circulation pattern influenced by the Himalayan -Tibetan Plateau, the tropical easterly jets have lead northern Africa to dry conditions. So, it is possible to settle the uplift age of the Himalayan-Tibetan Plateau from the beginning age of dry climatic condition in northern Africa.<BR>As a results, we could clarify two evidences as follows:<BR>1) Illite concentrations and magnetic susceptibility indicate concentrations of eolia n dust carrying from northern Africa have increased from 3.5 Ma ago. In other words, the recent atmospheric circulation, that is carrying eolian dust into the Mediterranean Sea, has been confirmed from 3.5 Ma ago.<BR>2) Based on oscillations of illite crystallinity during the 4.5 Ma, the northern Africa region became dry condition 0.8 Ma ago. We thought that this event of 0.8 Ma was caused by the uplift of the Himalayan-Tibetan Plateau.

    DOI CiNii

  • Preliminary results of the first scientific drilling on Lake Baikal, Buguldeika site, southeastern Siberia

    S. Colman, M. Grachev, P. Hearn, S. Horie, T. Kawai, N. Logachov, V. Antipin, V. Fialkov, A. Gorigljad, B. Tomilov, B. Khakhaev, S. Kochikov, V. Lykov, L. Pevzner, A. Bucharov, N. Logachev, V. Mats, A. Bardardinov, E. Karabanov, E. Baranova, O. Khlystov, V. Khrachenko, M. Shimaraeva, E. Kornakova, S. Efremova, E. Stolbova, A. Gvozdkov, V. Kravchinski, T. Fileva, S. Kashik, T. Khramtsova, I. Kalashnikova, T. Rasskazova, V. Tatarnikova, R. Yuretich, V. Mazilov, K. Takemura, V. Bobrov, T. Gunicheva, H. Haraguchi, S. Ito, T. Kocho, M. Kuzmin, M. Markova, V. Pampura, O. Proidakova, H. Sawatari, A. Takeuchi, K. Toyoda, S. Vorobieva, A. Ikeda, A. Marui, T. Nakamura, K. Ogura, T. Ohta, J. King, J. Peck, H. Sakai, T. Yokoyama, A. Hayashida, E. Bezrukova, S. Fowell, N. Fuji, P. Letunova, V. Misharina, N. Miyoshi, G. Chernyaeva, I. Ignatova, E. Likhoshvai, E. Stoermer, L. Granina, O. Levina, P. Dolgikh, R. Ishiwatari, F. Lazo, N. Lutskaia, W. Orem, E. Wada, D. Williams, K. Yamada, S. Yamada, E. Callander, L. Golobokoval, L. Granina, P. Shanks, R. Dorofeeva, A. Duchkov

    Quaternary International   37   3 - 17  1997  [Refereed]

     View Summary

    The Baikal Drilling Project (BDP) is a multinational effort to investigate the paleoclimatic history and tectonic evolution of the Baikal sedimentary basin during the Late Neogene. In March 1993 the Baikal drilling system was successfuly deployed from a barge frozen into position over a topographic high, termed the Buguldeika saddle, in the southern basin of Lake Baikal. The BDP-93 scientific team, made up of Russian, American and Japanese scientists, successfully recovered the first long (>100 m) hydraulic piston cores from two holes in 354 m of water. High quality cores of 98 m (Hole 1) and 102 m (Hole 2), representing sedimentation over the last 500,000 years, were collected in 78 mm diameter plastic liners with an average recovery of 72% and 90%, respectively. Magnetic susceptibility logging reveals an excellent hole-to-hole correlation. In this report the scientific team describes the preliminary analytical results from BDP-93 hole 1 cores. Radiocarbon dating by accelerator mass spectrometry provides an accurate chronology for the upper portion of Hole 1. Detailed lithologic characteristics, rock magnetic properties and inorganic element distributions show a significant change to the depositional environment occuring at 50 m subbottom depth, approximately 250,000 BP. This change may be due to uplift and rotation of the horst block in the Buguldeika saddle. The sedimentary section above 50 m is pelitic with varve-like laminae, whereas the section below 50 m contains a high proportion of sand and gravel horizons often organized into turbidite sequences. Accordingly, high resolution seismic records reveal a change in sonic velocity at this depth. It is inferred that sedimentation prior to 250 ka BP was from the west via the Buguldeika river system. After 250 ka BP the Buguldeika saddle reflects an increase in hemipelagic sediments admixed with fine-grained material from the Selenga River drainage basin, east of Lake Baikal. Variations in the spore-pollen assemblage, diatoms, biogenic silica content, rock magnetic properties, clay mineralogy and organic carbon in the upper 50 m of BDP-93-1 reveal a detailed record of climate change over approximately the last 250,000 years. These variables alternate in a pattern characteristic of glacial/interglacial climatic fluctuations. The present age model suggests that the climate signal recorded in Lake Baikal sediments is similar to Late Quaternary signals recorded in Chinese loess sections and in marine sediments. Copyright © 1996 INQUA/ Elsevier Science Ltd.

    DOI

    Scopus

    57
    Citation
    (Scopus)

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Books and Other Publications

  • 「最新」地学事典

    地学団体研究会, 地学団体研究会最新地学事典編集委員会( Part: Contributor)

    平凡社  2024.03

  • 古生物学の百科事典

    日本古生物学会( Part: Contributor)

    丸善出版  2023.01 ISBN: 9784621307588

  • うつりゆく駿河湾(しずおかの文化4)人と自然の関わりから見た過去、現在、そして未来

    渋川 浩一, 中西 利典, 日下 宗一郎, 山田 和芳, 菅原 大助, 岡本 一利, 橋本 正洋, 印南 敏秀, 渡邊 眞一郎, 後藤 義正( Part: Contributor)

    ことのは社  2022.07 ISBN: 9784909882035

  • 百年先 : 地方博物館の大きな挑戦

    ふじのくに地球環境史ミュージアム( Part: Edit)

    静岡新聞社  2021.01 ISBN: 9784783805564

  • 環境考古学と富士山 第4号

    ふじのくに地球環境史ミュージアム, 静岡県富士山世界遺産センター( Part: Joint editor)

    雄山閣  2020.03 ISBN: 9784639024675

  • 実践 統合自然地理学: あたらしい地域自然のとらえ方

    岩田 修二

    古今書院  2018.06 ISBN: 4772242074

    ASIN

  • 環境考古学と富士山 第2号

    岸本 年郎, 田代 一葉

    雄山閣  2018.03 ISBN: 4639025629

    ASIN

  • 浜名湖は本当に塩水化したか-明応巨大地震(1498年)の大津波を考える-

    瀬戸浩二, 香月興太, 山田和芳( Part: Contributor)

    月刊さなるこ新聞  2018.02

  • 環境考古学と富士山 1(2017.3)

    松島 仁, 日下 宗一郎

    雄山閣  2017.03 ISBN: 4639024673

    ASIN

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Presentations

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Research Projects

  • Creation ofthe Anthropocene Geography and Environmental Studies

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research

    Project Year :

    2023.06
    -
    2027.03
     

  • クメール王朝の都市構造と社会基盤の解明-高精度地形情報を利用した実査より

    日本学術振興会  科学研究費助成事業 基盤研究(A)

    Project Year :

    2021.04
    -
    2026.03
     

    下田 一太, 本村 充保, 内田 悦生, 田畑 幸嗣, 佐藤 由似, 山田 和芳, 原口 強

  • 和歌山県ゆかし潟堆積物を用いた歴史時代の紀伊半島における環境史復元

    公益財団法人 東京地学協会  令和5年度調査・研究助成

    Project Year :

    2023.06
    -
    2024.05
     

  • Interdisciplinary research on mercury pollution by the ASGM, using the varved lacustrine sediments

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

    Project Year :

    2021.04
    -
    2024.03
     

  • The Empirical Research on Theories and Practices Concerning to the STEM Education Innovation for the Society 5.0

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

    Project Year :

    2020.04
    -
    2023.03
     

  • High-resolution reconstruction of brackish water ecosystem structure and its changes associated with cyclic climate change using by Holocene varve sediments

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research

    Project Year :

    2023.04
    -
    2026.03
     

  • 「どべ田んぼ」における土壌の生成と固定化に関する研究

    土科学センター財団  2022年度研究助成

    Project Year :

    2022.04
    -
    2023.03
     

    山田和芳、村尾 智、冨安卓滋

  • 目に見えない地層の縞(黒色有機年縞)がもつ古環境アーカイヴとしての有用性評価

    日本学術振興会  科学研究費助成事業 挑戦的研究(萌芽)

    Project Year :

    2021.07
    -
    2023.03
     

    山田和芳、藤木利之

  • The application of thick annually lake deposits in Finland as Anthropocene high-resolution environmental archives

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Challenging Research (Exploratory)

    Project Year :

    2020.07
    -
    2022.03
     

  • 八郎潟調整池における近年の底質環境変化の解明

    秋田県ジオパーク連絡協議会  令和3年度秋田県ジオパーク研究助成

    Project Year :

    2021.06
    -
    2022.02
     

    山田和芳,鹿島 薫

  • Examination of level 1.5 earthquake and tsunami in eastern edge of Nankai Trough, Japan

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

    Project Year :

    2017.04
    -
    2020.03
     

    Akihisa Kitamura

     View Summary

    The Japanese government presented simulations of possible maximum seismic movements and tsunami heights (termed Level 2 earthquakes and tsunamis) caused by Nankai megathrust earthquakes, based on recognition of mega-tsunami at the 2011 Tohoku-oki earthquake. Kitamura and co-workers examined tsunami deposits in Shizuoka prefecture, and showed that there is no evidence for a Level 2 tsunami over the past 4000 years. But, two Level 1.5 earthquakes and tsunamis, which are larger than level 1, but smaller than level 2, were detected. One is occurrence of megathrust earthquake and the earthquake-induced active of splay fault at Omaezaki. The other is increase in tsunami wave height was caused by earthquake-induced submarine landslides at Yaizu. This study shows the following findings: (1) The AD1361 Shohei (Koan)Tokai earthquake caused >2.5 m uplift at Omaezaki; (2) Megathrust earthquake occurred at ca AD400 at Suruga Trough. Scientific data of analysis of Yaizu Plain has been submitted.

  • Elucidation of cyclic climate change by ultra high-resolution analysis during the late Holocene in subarctic region, Hokkaido

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

    Project Year :

    2017.04
    -
    2020.03
     

    Seto Koji

     View Summary

    In this study, the formation process of varved sediments and the definition of lamina as a varve in Lake Mokoto and Lake Abashiri in Hokkaido were established. We analyzed the detailed characteristics of recent flood events and discussed the issue of sediment runoff. Based on that, it was clarified that some past flood events can be used as a key bed. The varved ages were counted in the late Holocene, and sediment flux and organic carbon flux are estimated. From the results, we could presume the artificial and natural environmental changes in the lake and its basin. By analyzing the detailed varve sediments in the lake Mokoto, cyclic climate events such as 11-year climate change corresponding to the sunspot cycle were revealed.

  • Search for landscape reconstruction by ancient DNA of varves

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Challenging Research (Exploratory)

    Project Year :

    2017.06
    -
    2019.03
     

    Yamada Kazuyoshi

     View Summary

    In this study, environmental DNA analysis is conducted on annually laminated sediments in Japan to verify whether it is possible to comprehensively grasp information on flora and fauna and human activity history that can not be recovered from chemical compositions and microfossils. I tried for the first time in the world. For that purpose, the analysis method of environmental DNA analysis is applied to the lake sediments which are different in the climate change and cultural anthropologically different landscapes such as Hokkaido and Shizuoka, and the analysis method of environmental DNA analysis is used. We constructed the biota and human activity history as time series changes.
    As a result, it was found that it is possible to discuss the presence or absence of the Itou that had once lived in the Lake Alga Lake. However, it was suggested that the degree of damage to DNA is different depending on the sedimentary environment and the difference in sedimentary age.

  • Asian monsoon activities reconstructed from varved sediments in Lake Ichi-no-Megata

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Young Scientists (B)

    Project Year :

    2013.04
    -
    2016.03
     

    YAMADA Kazuyoshi

     View Summary

    Thirty-seven meter long sediment cores were recovered from Lake Ichi-no-Megata, northeast Japan. Six lithozones were classified based on detailed lithology and physical properties of the sediment cores. Most of the sediment sequences were thinly laminated except one interval from 26.3 to 31.7 m, which is composed of volcanic materials of an adjacent maar, Lake San-no-Megata. Although these laminations had different structures and composition between the Holocene and the last glacial period, they have been related to an annual cycle of deposition, i.e. a varve. Multiple AMS 14C dates enabled us to establish the detailed chronology agreed well with tephrostratigraphy over the last 30,000 years. The age-depth plots indicate a stable deposition environment with a linear sedimentation rate (0.727 mm/year) since after 25,000 cal BP. The continuous laminated sediments have great potential for high-resolution study of the past environmental changes since the last glacial period.

  • International Joint Research for Establishment of Tephra Network in the Philippines

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

    Project Year :

    2012.04
    -
    2016.03
     

    Okuno Mitsuru, TAGUCHI Sachihiro, KOBAYASHI Tetsuo, NAKAMURA Toshio, TORII Masayuki, FUJIKI Toshiyuki, TAKASHIMA Isao, HARAGUCHI Tsuyoshi, YAMADA Kazuyoshi, NAKANISHI Toshimichi

     View Summary

    The Philippines has many volcanoes due to subduction along its trenches similar to the tectonic setting of Japan. In this study, we have conducted geological surveys in Pinatubo, Taal, and Irosin volcanoes, located in Luzon, and Matutum and Parker volcanoes located in Mindanao Island, in collaboration with the Philippine Institute of Volcanology and Seismology (PHIVOLCS). We tried to reconstruct the eruptive history of these volcanoes, and establish a chronological framework of widespread tephras. Cored sediments were obtained from Paitan Lake, about 60 km northeast of Pinatubo Volcano. Ash layers were identified within these cores, and were given ages, with high precision.

  • High-resolution environmental reconstruction for the Pacific civilizations using annually laminated lake sediments

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)

    Project Year :

    2009.07
    -
    2014.03
     

    YONENOBU Hitoshi, TOYODA Kazuhiro, GOTANDA Katsuya, YASUDA Yoshinori, OKUNO Mitsuru, NASU Hiroo, YAMADA Kazuyoshi, MORITA Yoshimune, HAYSHIDA Akira, HARAGUCHI Tsuyoshi, YOKOYAMA Yusuke, OHYAMA Motonari, SAITO-KATO Megumi, ODA Hirotaka

     View Summary

    The purpose of the study is to clarify the relationship between environmental changes and the ancient civilizations in the Pacific regions. Sediment cores were recovered from the lakes in Guatemala, Southern Peru, Cambodia and Ryukyu Islands. These were analyzed to reconstruct the past environmental changes, i.e., climate, natural disasters, vegetation and anthropogenic activities over the regions. Radiocarbon (C-14) determinations obtained from annually laminated sediments in Lake Suigetsu were incorporated in the C-14 calibration curve, Intcal 13, which contributes to the high-precision dating in archaeology and geosciences. The environmental reconstructions were compared to the societal changes in the civilizations.

  • 土の年輪は、樹木年輪になれるのか? -湖沼年縞の年輪年代学的研究への応用-

    財団法人 国土地理協会 

    Project Year :

    2011.04
    -
    2012.03
     

    山田 和芳

  • Environmental Annual History and Rise and Fall of the Rice-Culltivating and Fishing Civilization by the Annual Study of Laminated Sediments

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (S)

    Project Year :

    2006
    -
    2010
     

    YASUDA Yoshinori, KASAYA Kazuhiko, HIRAO Yoshimitsu, UNO Takao, TAKEMURA Keiji, FUKUSAWA Hitoshi, HATASHIDA Akira, SAITO Megumi, YAMADA Kazuyoshi, TOYAMA Shuichi, MATSAUSHITA Takayuki, FUJIKI Toshiyuki, NASU Hiroo, MORI Yuuichi, SHINOZUKA Ryoji, GOTANDA Katsuya, AKAYAMA Yozo, NOJIMA Yoko, MIYATSUKA Shou, LI Xun, VOEUM Vuthy, PHOEURN Chuch

     View Summary

    By reconstructing the precise annual history based on the examination of annually laminated sediments, this project elucidated how the rise and fall of rice-cultivating and fishing civilizations in monsoon Asia had influenced by climatic fluctuations. As for Khmer civilization in particular, an archaeological investigation of Phum Snay yielded a series of new findings including the discovery of an altar of water. It became clear that the rice-cultivating and fishing civilization is a civilization centered on water and that the climatic change had a considerable impact for the collapse of Angkor civilization.

  • 汽水湖沼の堆積学的研究に基づく完新世. 気候変動と人間活動イベントの検出

    日本学術振興会  特別研究員奨励費

    Project Year :

    2005.04
    -
    2008.03
     

    山田 和芳

  • 汽水湖沼の堆積学的研究に基づく完新世気候変動と人間活動イベントの検出

    日本学術振興会  科学研究費助成事業 特別研究員奨励費

    Project Year :

    2005
    -
    2007
     

    山田 和芳

     View Summary

    本研究は,山陰地方の汽水湖沼堆積物を用いて,完新世における自然環境変動の検出と人間活動史との関連を解明することを目的とするものである.平成19年度は,これまでに出雲平野および宍道湖,神西湖,中海で掘削されたボーリングコア解析を通じて,完新世における汽水域の形成と平野の地形発達の関連を堆積学的および地球化学分析によって詳細に明らかにすることができた.とくに,完新世以降の出雲平野の地形発達史を,高精度に復元できたことは本研究によってはじめて成し得たことである.これの成果を論文としてまとめることができた.また,近過去の環境復元研究では,中海および宍道湖を対象として,複数のショートコアを採取して,過去100年間の環境変動の検出を試みた.この研究成果の特筆できる点として,富栄養化が少なくとも1950年には生じていていること,本庄工区の近年の底質環境は改善されつつあることの新知見を得ることができた.さらに,今年度から着手した秋田県一の目潟コアの研究では,世界的にも類を見ない過去三万年間の連続した年縞堆積物を発見した.この年縞堆積物の解析により,東アジアの環境変動を高精度に復元できる手がかりをつかんだ.本年度中は,イニシャルレポートとして研究成果の基礎的な段階を報告した.今後,一の目潟コア研究は,重点的に進めていくことになり,これら研究成果は,国内外の学会等で講演していくとともに,また現在国際誌に投稿中である.

  • 中国エルハイ湖堆積物による過去10万年間のモンスーン変動の高精度復元とグローバルな気候変動のトリガーの解明

    公益財団法人アサヒグループ学術振興財団 

    Project Year :

    2005.04
    -
    2006.03
     

    山田 和芳

  • タイ南部ソンクラー湖における汽水域の形成環境と近年の地球温暖化との関係の解明

    財団法人福武学術文化振興財団 

    Project Year :

    2004.04
    -
    2005.03
     

    山田 和芳

  • 湖沼・レス堆積物を用いた東アジアにおける最終氷期以降のモンスーン変動の高精度復元

    日本学術振興会  特別研究員奨励費

    Project Year :

    2001.04
    -
    2003.03
     

    山田 和芳

▼display all

Misc

  • How does a biological population adapt to a new colonized habitat?: case study of a Daphnia pulex population colonized in Lake Fukami-ike, Nagano analyzed by dormant eggs preserved in lake sediments.

    大竹裕里恵, 大槻朝, 占部城太郎, 陶山佳久, 松尾歩, 廣田峻, 印南秀樹, 木村成子, 山田和芳, 吉田丈人, 吉田丈人

    日本進化学会大会プログラム・講演要旨集(Web)   22nd  2020

    J-GLOBAL

  • Evaluation of the effects of mercury pollution caused by artisanal/small-scale gold mining-new movement of varved environmental history research-

    山田和芳, 村尾智

    Proceedings of Symposium on Geo-Environments and Geo-Technics   30th  2020

    J-GLOBAL

  • Trace element distributions of Lake Ogawara sediment core: Implication for the past sea level change at the late Holocene

    奈良郁子, 奈良郁子, 山崎慎一, 渡邊隆広, 土屋範芳, 山田和芳, 安田喜憲

    日本地球化学会年会要旨集(Web)   67th  2020

    J-GLOBAL

  • Adaptation mechanism of Daphnia pulex population in new colonized habitat: temporal analysis of genetic structure and traits.

    大竹裕里恵, 大槻朝, 占部城太郎, 陶山佳久, 松尾歩, 廣田峻, 印南秀樹, 木村成子, 山田和芳, 吉田丈人, 吉田丈人

    日本ベントス学会・日本プランクトン学会合同大会講演要旨集   2020  2020

    J-GLOBAL

  • 2017 activity report on a regional contribution program conducted by Nagoya University: "Investigation of natural and environmental history in the Tokai region" for the higher grade elementary school students

    Minami Masayo, Kitagawa Hiroyuki, Yamada Kazuyoshi, Sugawara Daisuke, Kitamura Akihisa, Enami Masaki, Kato Takenori, Ikeda Akiko, Nara Fumiko, Kurita Naoyuki, Yamane Masako, Nishida Masami, Kida Risako, Nakamura Toshio

    名古屋大学年代測定研究   2   92 - 97  2018.03

     View Summary

    We, the members of the Division for Chronological Research at the Institute for Space-Earth Environmental Research at Nagoya University, held a regional contribution program for the higher grade elementary school students on August 3–4, 2017: &quot;Investigation of natural and environmental history in the Tokai region&quot;. Twenty-seven students observed natural samples to experience earth and archaeological sciences. The first day began with lectures on tephra chronology and dendrochronology. After the lecture, the students took part in several hands-on experiments by using tephra and annual tree rings. On the second day they travelled to Shizuoka by bus and visited the Museum of Natural and Environmental History, Shizuoka to study natural and environmental history in the Tokai region. Later in the day they went to Miho no Matsubara to observe the states of coastal erosion and pine wilt disease. Finally, they went to Nihondaira to study about a movement of the earth&#039;s crust. The program ended a success. The post-program questionnaire shows that the participants enjoyed the program and learned many new things.宇宙地球環境研究所年代測定研究部は,静岡県ふじのくに地球環境史ミュージアムの山田和芳教授,菅原大助准教授,静岡大学理学部の北村晃寿教授と協力し,平成29年8月3日(木)と4日(金)の2日間にわたり,小学高学年生27名を対象とした夏休み体験学習「東海の地球環境史を学ぼう」を行いました.教室での講義だけでは得られ難い実体験の機会は,子どもたちの科学への興味や関心をより高めるきっかけになり,本体験学習の目的は十分達成できたと考えられる.

    CiNii

  • 秋田県一ノ目潟のコア堆積物から得られた古地磁気方位の変動の信頼性

    安樂和央, 林田明, 北場育子, STAFF Richard A, 原口強, 篠塚良嗣, 山田和芳, 五反田克也, 米延仁志

    日本地球惑星科学連合大会予稿集(Web)   2016   ROMBUNNO.SEM34‐02 (WEB ONLY)  2016

    J-GLOBAL

  • 沖縄県羽地内海堆積物の残留磁化:磁性鉱物種と続成作用の検討

    高梨祐太郎, 林田明, 山田和芳, 五反田克也, 米延仁志

    日本地球惑星科学連合大会予稿集(Web)   2015   ROMBUNNO.SEM34‐P07 (WEB ONLY)  2015

    J-GLOBAL

  • P29. The Sector Collapse Process of Iriga Volcano, Philippines

    Terabori Yoshihiro, Haraguchi Tsuyoshi, Okuno Mitsuru, Fujiki Toshiyuki, Yamada Kazuyoshi

      26   223 - 224  2014

    CiNii

  • 沖縄県羽地内海堆積物の磁気特性:赤色土壌流入と続成作用の検討

    高梨祐太郎, 林田明, 山田和芳, 五反田克也, 米延仁志

    地球電磁気・地球惑星圏学会総会及び講演会予稿集(CD-ROM)   136th   ROMBUNNO.R004‐P010  2014

    J-GLOBAL

  • Temporal variation of very fine elemental carbon in sediments from the Lake Kushu in the Rebun Island during the last 3000 years

    Irino Tomohisa, Nakai Yoshie, Yamamoto Masanobu, Miyazaki Yuzo, Kawamura Kimitaka, Yamada Kazuyoshi, Yonenobu Hitoshi

    Abstracts of Annual Meeting of the Geochemical Society of Japan   61 ( 0 ) 287 - 287  2014

     View Summary

    遠距離輸送されるバイオマス燃焼起源物質の定量を目指して,堆積物中の極細粒元素状炭素(EC)量評価のために,Thermal optical transmittance法の応用を検討した.スクロース,フミン酸,フルボ酸,フラーレンのEC・有機炭素(OC)分析を行った結果,O2雰囲気,550℃-700℃に耐えるOCも存在することが分かったので,700℃-850℃で検出されるフラクションのみをECとして定義した.この方法で,礼文島・久種湖の湖底堆積物コアから選んだ試料を,2μmを境に粗粒および細粒に分画し,それぞれの粒度画分についてEC・OC分析を行った.その結果,粗粒・細粒画分中のEC・OC変動が異なる事が分かり、粗粒ECはローカルな,細粒ECはローカル,遠方両方のバイオマス燃焼起源である可能性が示唆された.ECの細粒/粗粒比変動は大陸規模でのバイオマス燃焼変動を反映する可能性がある.

    DOI CiNii

  • Variations of limnological environment since the LGM inferred from the sediments of Lake Ichi-no-Megata maar, northeast Japan

    Yamada Kazuyoshi, Shinozuka Yoshitsugu, Seto Koji, Yonenobu Hitoshi, Gotanda Katsuya, Haraguchi Tsuyoshi, Yasuda Yoshinori

    Annual Meeting of the Geological Society of Japan   2013 ( 0 ) 170  2013.09

     View Summary

    発表では、一の目潟ボーリングコアを用いて、新しい編年モデルを構築し、高時間分解能地球化学分析に基づき、26,000年前以降の東北日本の陸上古環境変動を復元した結果を報告する。秋田県男鹿半島に位置する一の目潟では、2006年秋、湖中央部においてシンウォールコアリングによる平行コアリング法(Nakagawa et al., 2012)によって、湖底下から約37mまで完全な連続堆積物(IMG06コア)を採取している。IMG06コアのコンポジット深度-年代モデルを構築する際、イベントフリー編年モデルを作成した。つまり、堆積物中で、層厚1cm以上褐色層(上方細粒化の構造あり)をイベント層として、これら一過性の堆積物を除外したイベントフリー・コンポジット深度に対して、合計74個の放射性炭素年代値から求めた暦年代値をプロットして、編年モデルを作成した。なお、イベント層は、全層にほぼ均一に挟在し全体の約4割を占めることが明らかになった。その結果、過去28,000年間において、堆積速度の異なる3つのステージが存在して、0.5~16 ka、16~24 ka、24~28 kaで、それぞれ0.325、0.463、0.786 mm/yearと求められた。また、コアの表層部(コンポジット深度で0~80 cm)は、年縞計数により、435年分の堆積物であることも示された。次に、気候プロキシーによる環境変動を明らかにするために、深度26.1mより上位の年縞堆積物の部分(タービダイト層は含まない)の試料(n=887)についてCNS元素分析及びICP-AESによって総数17の主要及び微量化学成分量を求めた。分析の試料間隔は平均15 mmであり、分析用試料は層厚2~10 mmで分取し、その時間分解能は最大で30年と見積もられた。これらの高時間分解能試料を用いた無機分析結果に基づき、気候プロキシーを用いて推定された過去26,000年間の男鹿半島周辺の気候変動は、大局的に15 kaまでは寒冷乾燥期、15-9 kaは、寒冷乾燥期から温暖湿潤期移行期、9 ka以降は、温暖湿潤期となっている。また、変動の振幅の激しさは、15-9kaで最も大きくになる一方、9ka以降では中間程度、26-15 kaでは極端に小さくなっている。とくに、晩氷期の気候変動に着目すると、今回の一目潟堆積物の記録は、15 kaより緩やかな気候温暖湿潤化が生じており、その中で、14 ka付近と、12.5-11.3 kaに、一時的な気候寒冷乾燥化傾向が認められる。このような傾向は、琵琶湖堆積物の記録と同調する一方、中国の石筍やグリーンランドの氷床コアの記録とは類似しない。この原因として、男鹿半島周辺の気候変動が、アジアモンスーンのような大気循環の変化よりも、海水面の急激な上昇による対馬暖流の流入による気候変動の影響を大きく受けた可能性があげられる。15 kaからのゆるやかな温暖化傾向は、14.6 ka頃の海水準変動の急激な上昇(MWP1a:Yokoyama and Esat, 2011)にともない、それが対馬暖流の日本海への本格的流入を促し、それが、男鹿半島で徐々に気候温暖化を生じさせたと解釈される。一方、ヤンガードリアス期は、男鹿半島では12.5-11.3 kaあたりに存在しているものの、そのシグナルは弱い。これは、男鹿半島のような日本列島の日本海沿岸地域では、顕著にあらわれなかった可能性がある。

    CiNii J-GLOBAL

  • 青森県小川原湖における水環境の変化が及ぼす堆積システムへの影響

    永島郁, 瀬戸浩二, 吉田明弘, 篠塚良嗣, 山田和芳, 米延仁志

    日本陸水学会大会講演要旨集   78th   176  2013.09

    J-GLOBAL

  • 沖縄県本島河川からの土砂流出による内海底質への影響

    加藤みやび, 瀬戸浩二, 山田和芳, 米延仁志

    日本陸水学会大会講演要旨集   78th   177  2013.09

    J-GLOBAL

  • Change of sedimentary environment recorded to the coastal lagoon sediments in Lake Ogawara, Aomori Prefecture.

    Nagashima Aya, Seto koji, Watanabe Takahiro, Nara Fumiko, Yasuda Yoshinori, Yamada Kazuyoshi, Nonenobu Hitoshi

    Annual Meeting of the Geological Society of Japan   2013 ( 0 ) 166  2013.09

    CiNii J-GLOBAL

  • 青森県小川原湖における汽水湖沼の水質環境と底質環境

    永島郁, 瀬戸浩二, 山田和芳, 米延仁志

    地学団体研究会総会講演要旨集   67th   25 - 26  2013.08

    J-GLOBAL

  • 年縞堆積物による環太平洋諸文明の高精度環境史復元

    山田和芳, 米延仁志

    地学団体研究会総会講演要旨集   67th   21 - 22  2013.08

    J-GLOBAL

  • 完新世におけるカンボジア,トンレサップ湖の形成時期と古環境変動

    福本侑, 米延仁志, 原口強, 瀬戸浩二, 山田和芳, 林田明, 徳永朋祥, 篠塚良嗣

    地学団体研究会総会講演要旨集   67th   45 - 46  2013.08

    J-GLOBAL

  • 最終氷期最寒冷期以降の一の目潟における陸水環境の変化

    山田和芳, 篠塚良嗣, 瀬戸浩二, 岡崎裕子, 米延仁志, 五反田克也, 原口強, 安田喜憲

    日本地理学会発表要旨集   ( 83 ) 139  2013.03

    J-GLOBAL

  • 青森県小川原湖における水環境による底質環境への影響

    永島郁, 瀬戸浩二, 岡崎裕子, 中島広海, 山田和芳, 米延仁志

    日本陸水学会大会講演要旨集   77th   168  2012.09

    J-GLOBAL

  • 縞状珪藻質泥岩の高精度年代決定法への応用と課題

    齋藤めぐみ, 山田和芳

    日本第四紀学会講演要旨集   42   134  2012.08

    J-GLOBAL

  • 湖沼年縞によるイベント地層の年代決定法

    山田和芳, 齋藤めぐみ

    日本第四紀学会講演要旨集   42   133  2012.08

    J-GLOBAL

  • 鹿児島県藺牟田池で採取されたコア試料の層序と磁気特性

    横田敬作, 林田明, 山田和芳, 原口強, 井村隆介, 上田圭一, 米延仁志

    日本第四紀学会講演要旨集   42   256 - 257  2012.08

    J-GLOBAL

  • 秋田男鹿,一の目潟堆積物から推定された過去26,000年間の気候変動

    山田和芳, 篠塚良嗣, 米延仁志, 五反田克也, 原口強, 安田喜憲

    日本第四紀学会講演要旨集   42   164 - 165  2012.08

    J-GLOBAL

  • Evaluation of the efficacy of the lacustrine varved sediments as the detector for paleo earthquake and tsunami events

    YAMADA Kazuyoshi, SAITO-KATO Megumi, HARAGUCHI Tsuyoshi, GOTANDA Katsuya, YONENOBU Hitoshi, NAKAGAWA Takeshi, TAKEMURA Keiji

    Proceedings of the General Meeting of the Association of Japanese Geographers   2012 ( 0 ) 172 - 100039  2012.03

     View Summary

    We have evaluated the efficacy of the lacustrine varved sediments as the detector for paleo earthquake and tsunami events.

    DOI CiNii J-GLOBAL

  • Records for high time-resolution volcanic eruptions::tree ring, varve sediments and humic soil

    Oikawa Teruki, Hoshino Yasuharu, Yamada Kazuyoshi, Ban Masao, Okuno Mitsuru

    Jour. Geol. Soc. Japan   117 ( 12 ) XIII  2011.12

    Article, review, commentary, editorial, etc. (scientific journal)  

    DOI CiNii

  • 東南極・高塩分塩湖すりばち池に記録された後期完新世の古環境と古気候変動

    中島広海, 瀬戸浩二, 香月興太, 金子亮, 山田和芳, 伊村智

    日本地質学会学術大会講演要旨   118th   154  2011.09

    DOI J-GLOBAL

  • 東南極・高塩分塩湖すりばち池の完新世後期における蒸発・濃縮過程

    中島広海, 瀬戸浩二, 香月興太, 金子亮, 山田和芳, 伊村智

    日本第四紀学会講演要旨集   41   42-43  2011.08

    J-GLOBAL

  • 東北日本の古気候データからみた完新世の東アジアモンスーンの活動性

    吉田明弘, 米延仁志, 守田益宗, 竹内貞子, 篠塚良嗣, 山田和芳, 五反田克也, 安田喜憲

    日本第四紀学会講演要旨集   41   24 - 25  2011.08

    J-GLOBAL

  • 湖沼年縞の年輪年代学的研究の試み~長野県深見池を例に~

    山田和芳, 米延仁志, 星野安治, 大山幹成, 小田寛貴, 北川淳子, 安田喜憲, 斉藤めぐみ

    日本第四紀学会講演要旨集   41   150 - 151  2011.08

    J-GLOBAL

  • 男鹿半島,一の目潟マール堆積物の湖沼年縞と過去100年間の自然災害・人間活動史

    山田和芳, 米延仁志, 小田寛貴, 斉藤めぐみ, 五反田克也, 原口強, 安田喜憲

    日本第四紀学会講演要旨集   41   14 - 15  2011.08

    J-GLOBAL

  • Holocene paleo-environmental changes in Lake Ogawara, Aomori Prefecture, northeast Japan –preliminary report–

    Yamada Kazuyoshi, Ohyama Motonari, Tyler Jonathan, Turunen Saija, Saarinen Timo, Hayashida Akira, Yasuda Yoshinori, Shinozuka Yoshitsugu, Yoshida Akihiro, Yonenobu Hitoshi, Gotanda Katsuya, Haraguchi Tsuyoshi, Hoshino Yasuharu, Inagaki Tetsuya, Okuno Mitsuru

    Annual Meeting of the Geological Society of Japan   2010 ( 0 ) 104 - 104  2010.09

    DOI CiNii J-GLOBAL

  • Lake Megata2006Project:湖沼年縞堆積物による古環境復元

    米延仁志, 山田和芳, 五反田克也, 北川淳子, 篠塚良嗣, 奥野充, 斎藤めぐみ, 原口強, 安田喜憲

    日本文化財科学会大会研究発表要旨集   25th   154 - 155  2008.06

    J-GLOBAL

  • P-139 Faunal change of fossil ostracodes by anthropogenic change during the last 80 years in Lake Nakaumi, southwest Japan

    Ishida Katsura, Oba Marie, Yamaguchi Keiko, Takata Hiroyuki, Yamada Kazuyoshi, Kunii Hidenobu

      114   285 - 285  2007.09

    CiNii

  • Present environment features and the variation of sedimentary process during Holocene in Lake Songkla, south Thailand

    YAMADA Kazuyoshi, SETO Koji, SAKAI Saburo, ISHIDA Katsura, TANAVUD Charlchai, TAKAYASU Katsumi

      ( 69 ) 233 - 233  2006.03

    CiNii

  • Paleoenvironmental changes at Lake Jinzai, Shimane Prefecture since the 16^<th> century recorded in the lacustrine sediments

    YAMADA Kazuyoshi

      ( 67 ) 263 - 263  2005.03

    CiNii

  • Critical environmental change events around 4,000yrs B.P. and environmental changes in historical times recorded in the lacustrine sediments of Lake Jinzai, Shimane Prefecture

    YAMADA Kazuyoshi, TAKAYASU Katsumi

      ( 66 ) 86 - 86  2004.09

    CiNii

  • O-25 Stratigraphy and geochemical analyses of alluvium cores and the Holocene environmental variations in western part of Izumo Plain, southwest Japan

    YAMADA Kazuyoshi, TAKAYASU Katsumi

    Annual Meeting of the Geological Society of Japan   2004 ( 0 ) 38 - 38  2004

    DOI CiNii

  • Paleo-environmental changes during 100 ka reconstructed from Lake Erhai lacustrine sediments Yunnan Province, China

    YAMADA Kazuyoshi

      63   243 - 243  2003.03

    CiNii

  • Ecological responses to environmental changes in Lake Biwa during the past 40 ka

    KATO Megumi, TANIMURA Yoshihiro, YAMADA Kazuyoshi, FUKUSAWA Hitoshi

    Annual Meeting of the Geological Society of Japan   2003 ( 0 ) 204 - 204  2003

    DOI CiNii

  • Paleo-environmental changes since the last glacial period based on the quantitative reconstruction of paleo-precipitation from loess-paleosol sequences in Chine

    YAMADA Kazuyoshi, FUKUSAWA Hitoshi

      ( 62 ) 135 - 135  2002.09

    CiNii

  • O-412 Paleo-precipitation changes during the last glacial stages detected by the loess : paleosol sequences and lacustrine sediments in China

    YAMADA Kazuyoshi, FUKUSAWA Hitoshi

    Annual Meeting of the Geological Society of Japan   2002 ( 0 ) 204 - 204  2002

    DOI CiNii

  • Paleo Asian summer monsoon activity records during late Pleistocene to Holocene detected in loess-paleosol sequence in Lanzhou, Gansu, China

    YAMADA Kazuyoshi, KOROGI Chiharu, OKUNO Mitsuru, FUKUSAWA Hitoshi

      60   42 - 42  2001

    CiNii

  • O-66 Environmental changes since the last glacial stages detected by the loess-paleosol sequences in northeastern China

    YAMADA Kazuyoshi, FUKUSAWA Hitoshi

    Annual Meeting of the Geological Society of Japan   2000 ( 0 ) 44 - 44  2000

    DOI CiNii

  • On Late Glacial to Holocene rates of climatic and sea-level flucturations reconstructed by using varved sediments of Lake Suigetsu, western Japan.

    FUKUSAWA Hitoshi, YAMADA Kazuyoshi, FUJIWARA Osamu

      55   102 - 103  1999.03

    CiNii

  • Abrupt Climatic and Environmental Changes Since the Last Glacial Recorded in Non-glacial Varved Lake Sediments

    FUKUSAWA Hitoshi, KATO Megumi, YAMADA Kazuyoshi, FUJIWARA Osamu, YASUDA Yoshinori

    Summaries of Researches using AMS at Nagoya University   9   5 - 17  1998.03

     View Summary

    Our research group has collected sediment cores for the last 35 thousand years at Lake Tougou-ike of western Japan. Non-glacial varves of the brackish lake sediments could have recorded seasonal to annual changes of climate and sea-level. In addition, these sediments as timekeepers showed that climatic and sea-level changes of natural environments have influenced human activities.

    CiNii

  • 2. Spin Fluctuation Studied by Neutron Inelastic Scattering

    YAMADA Kazuyoshi

    Radioisotopes   46 ( 5 ) 311 - 316  1997.05

    CiNii

  • Last 2.4 Ma atomospheric circulation changes along the Japan Sea-Chinese Loess Plateau - the Mediterranean Sea transect, caused by uplift of the Himalayan- Tibetan Plateau.

    FUKUSAWA Hitoshi, OOI Keiichi, YAMADA Kazuyoshi, IWATA Shuji, TORII Masayuki

      51   172 - 173  1997.03

    CiNii

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Syllabus

▼display all

Teaching Experience

  • h

    Waseda University  

    2023.04
    -
    Now
     

  • h

    Waseda University  

    2023.04
    -
    Now
     

  • w

    Waseda University  

    2023.04
    -
    Now
     

  • e

    Yamagata University  

    2023.01
    -
    Now
     

  • 地球環境史学特論

    早稲田大学  

    2020.04
    -
    Now
     

  • 地理学特論Ⅰ・Ⅱ

    早稲田大学  

    2022.04
    -
    2023.03
     

  • 世界地誌学

    早稲田大学  

    2019.10
    -
    2023.03
     

  • 基礎地理学

    早稲田大学  

    2019.10
    -
    2023.03
     

  • Earth Science System

    Shimane University  

    2022.11
    -
    2022.12
     

  • 現代の地球科学

    早稲田大学  

    2019.10
    -
    2020.03
     

  • ムセイオン:MUSEUMと文化

    静岡県立大学  

  • シズオカ学

    静岡県立大学  

  • 環境資源学

    千葉商科大学  

  • 地理学

    千葉商科大学  

  • 地学実験

    日本獣医畜産大学  

  • 地球科学

    立教大学、中央大学  

  • 地球文明論

    鳥取環境大学  

  • 環境史学

    静岡大学  

▼display all

 

Social Activities

  • 静岡県の成り立ちと自然環境

    静岡市環境大学 

    2022.07
    -
     

  • 地理学者になった自分が伝えたいこと-過去・現在・未来-

    静岡STEMアカデミー 

    2022.06
    -
     

  • 「ハザードマップで旅してみた」

    NHK  レギュラー番組への道 

    2022.06
    -
     

  • 科学情報の収集と取捨選択について

    静岡科学館る・く・る  SC養成講座 

    2022.05
    -
     

  • 科学情報の収集と取捨選択について

    静岡科学館る・く・る 

    2021.11
    -
     

  • 海洋プラスチックごみ問題の解決に向けて

    裾野市婦人会 

    2021.10
    -
     

  • 三保半島の成り立ち

    静岡市  静岡市環境大学 

    2021.08
    -
     

  • 遠州遺産100プロジェクト 中田島砂丘 ー天竜川が造った遠州遺産-

    遠州遺産100プロジェクト YouTubeチャンネル 

    2021.06
    -
     

  • 海洋プラスチックごみ問題に関する指導法講座2(解説編)

    静岡県公式YouTubeチャンネル 

    2021.06
    -
     

  • 海洋プラスチックごみ問題に関する指導法講座1(実践編)

    静岡県公式YouTubeチャンネル 

    2021.06
    -
     

  • 岩石や地層をみると、 浜松のすごさがもっとわかる

    浜松市立富塚中学校 

    2021.03
    -
     

  • SDGs基礎講習会 Let's SDGs

    静岡呉服町名店街 

    2021.03
    -
     

  • 中田島砂丘の形成について

    中田島砂丘観光協会 

    2020.12
    -
     

  • 「海洋プラスチック問題」を考えよう

    静岡市立千代田東小学校 

    2020.10
    -
     

  • 海洋プラスチックごみによる海洋汚染

    静岡県地域女性協議会 

    2020.09
    -
     

  • 海洋プラスチック汚染の状況とリスク

    静岡市環境大学 

    2020.08
    -
     

  • 出張環境教室 フロシキと地球環境と未来

    ラッシュ静岡店 

    2020.03
    -
     

  • 出張地球家族会議

    スターバックスコーヒー蔦屋書店静岡店ほか 

    2019.05
    -
    2020.03

  • 環境セミナー「環境を守るとは?-自然界と人間活動の共生に向けて」

    2020.02
    -
     

  • 科学コミュニケーター育成講座 ふじのくに地球環境史ミュージアムの科学コミュニケーション活動

    静岡科学館る・く・る 

    2020.02
    -
     

  • 指導法講座 海洋プラ汚染の実態と伝え方

    静岡県 

    2020.01
    -
     

  • おさだの海シリーズ講演会 マイクロプラスチック問題を考える

    静岡市長田生涯学習センター 

    2020.01
    -
     

  • フラとプラ

    伊豆SS 

    2019.12
    -
     

  • 静岡県地球温暖化防止活動推進センター リーフレット「COOL CHOICEで守ろう!焼津の海」

    2019.12
    -
     

  • 海洋ゴミから地球を救う! 第13回富士市環境フェア

    富士市 

    2019.11
    -
     

  • 静岡大学FSSメインレクチャー 湖の底から、歴史を読み解く

    静岡大学FSS 

    2019.10
    -
     

  • 第399回自然セミナー講演会 奇跡の泥「年縞」が注目される理由

    2019.10
    -
     

  • バックキャスト思考トレーニング

    静岡大学教育学部付属中学校 

    2019.10
    -
     

  • シニア自然大学校 ふじのくにで地球環境史を読み解く

    2019.04
    -
     

  • プラスチックの功罪

    スターバックスマークイズ静岡店  第2回出張地球家族会議 

    2018.12
    -
     

  • プラスチックの功罪

    スターバックス蔦屋書店静岡本店  第1回出張地球家族会議 

    2018.11
    -
     

  • 地理学者が富士宮のスゴサをこっそり教えます

    富士宮市立中央図書館 

    2018.08
    -
     

  • すごいぞ!富士山~富士山がつくった静岡の豊かさ

    静岡県富士山世界遺産センター  館内講座 

    2018.08
    -
     

  • 第56回静岡夜店市

    2018.08
     
     

  • 静岡県の環境史

    吉田町シニアカレッジ 

    2018.04
    -
     

  • 第3回ジオパーク学術研究発表会

    伊豆半島ジオパーク推進協議会 

    2018.03
    -
     

  • 地球科学新時代

    静岡県立清水東高校  第2回SSH特別講義 

    2022.12
    -
     

  • 健康とSDGs

    静岡呉服町名店街  SDGs勉強会 

    2022.12
    -
     

  • 県内海洋プラスチック問題の現状と 解決への最新の取組

    静岡県  環境学習指導員フォローアップ研修 

    2022.11
    -
     

  • お街ゼミな~る2022

    静岡呉服町名店街 

    2022.11
    -
     

  • 親子で楽しむ環境ミニトーク バナナ・アボカドのひみつ

    ふじのくに地球環境史ミュージアム 

    2022.10
    -
     

▼display all

Sub-affiliation

  • Affiliated organization   Global Education Center

  • Faculty of Human Sciences   School of Human Sciences (Online Degree Program)

  • Faculty of Human Sciences   Graduate School of Human Sciences

Research Institute

  • 2022
    -
    2024

    Waseda Center for a Carbon Neutral Society   Concurrent Researcher

Internal Special Research Projects

  • アースサイエンスウィークプログラムの開発と実践に関する研究

    2023  

     View Summary

    AGI(American Geoscience Institute)との連携の一環として、市民が地球科学や自然科学の理解を深めるため、講演会、展示、サイエンスカフェなどをはじめとするイベントを実施することで、惑星の進化を学び、地球環境史を認識する機会提供を行うアースサイエンスウィークジャパンに関しての実践的な研究を展開した。以下2点の実践研究を展開することができた。1.商店街で化石発見ツアー企画・実施静岡伊勢丹デパートの壁や床に使用されている大理石に残る化石(二枚貝、巻貝)の観察、静岡市役所本庁舎玄関に使用されている琉球石灰岩に残る化石(サンゴ、貝類、カニ等)、浮月楼ビルの基礎の使用されている泥岩に残るアンモナイト化石を観察して、化石の解説や、地球史についての講座をおこなった。2.博物館イベント SDGsニューワールド「みずみずしい水」水からSDGsを考えるをテーマにして、水が、環境・健康リスクの軸ではなく、持続可能なまちづくりの基礎をつくっていることを知るものとして実施。水に様々なものを溶かす実験、軟水と硬水の違いを味覚を通じて感じる実験、食と水に関するクイズを通じて実施した。これらの体験を通じて、水を知ることは、地域やその文化を知ること。ひいては、地球環境と人のくらしの両立を実践できるものを理解することとして実施した。

  • 地理学・地球科学アウトリーチの効果的な普及・実践方法の研究

    2022  

     View Summary

    本研究では、地理学・地球科学アウトリーチの効果的な普及・実験方法を研究するために、博物館にてアウトリーチイベントを実施して、その教育的効果、誘客的効果を実証的に検証した。本研究では、「親子で楽しむ環境ミニトークバナナ・アボカドのひみつ」と題したクイズ形式のイベントを企画制作した。実物(果物)を用いて4択クイズを進行して、環境と人間活動の間に生まれるジレンマを感じる約30分のプログラムを作成した。そのプログラムはふじのくに地球環境史ミュージアム(静岡県静岡市)の2022年秋イベントのひとつとして実施した。15人(8組)の参加者に対してプログラムを実践して、その変容についてアンケート調査をおこなった。また主催者(博物館)からもインタビュー調査をおこなった。

  • 岡山城堀堆積物による過去200年間の環境変動の解明

    2021  

     View Summary

    本研究では,岡山市中心域の岡山城堀を対象として,約1メートルの柱状試料を採取して,堆積物層相観察やCNS分析を基にして過去100年間程度の環境変化を復元した.深度82~45 cmの砂質層は,周辺から一気に土砂が堆積した洪水堆積物であることが予想される.これは,昭和9(西暦1934)年の室戸台風による洪水イベントと考えられ,堀周辺を流れる旭川の決壊によるものとされる.また.深度31 cmの炭片の密集層は,TOC濃度のスパイクとしても認められ,昭和20(西暦1945)年の岡山空襲によるものと推定される.

  • 伊豆半島における過去の南海トラフ巨大地震・津波の発生履歴の解明

    2020  

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    本研究は、伊豆半島西部における過去1,000年間程度の津波履歴を解明することを目的とした。明神池湖底から採取したコアに対して、物性・粒度・CNS含有量の分析とともに、放射性炭素年代測定を実施した。その結果、堆積物の組成が大きく異なる18-19世紀の間に堆積したイベント地層があった。この地層は硫黄含有量や含砂率の高い層準という特徴が認められた。この地層の形成原因を考察するため、18-19世紀に伊豆を襲った宝永・安政東海地震津波をシミュレーションで再現したところ、安政東海地震の際は津波が西部の浜提を迂回して北側の井田の田園から明神池に流入したことから、この層は安政東海地震によるイベント堆積物である可能性がある。

  • 一ノ目潟における湖沼年縞の堆積機構の解明

    2014  

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    本研究は、男鹿半島(秋田県)に位置する一の目潟に堆積する湖沼年縞について、その堆積機構を明らかにすることを目的としている。

  • 年輪年代学的手法による一ノ目潟湖沼年縞の編年精度の検証

    2013  

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    本研究の目的は、秋田県一ノ目潟に現堆積している湖沼年縞堆積物の年縞計数による編年誤差の程度を知るために、年代誤差を持たない樹木年輪年代学の手法を用いて検討することである。その上で、将来的には年縞気候学という新分野開拓の足がかりにするものである。本研究課題では、まず現地調査をおこなった。2013年6月にリミノスコアラーによって、ミニアイスフィンガーコア堆積物の採取をおこなった。合計3本の良質なコアを採取することができた。コアは、採取後すぐに、鉛直方向に2分割して、堆積断面をデジタルカメラによって画像保存後、半分は年輪年代学的手法用に残し、残りの半分を堆積物薄片作製用、鉛・セシウム年代測定用にケースなどを用いて分割した。年輪計測システムおよび堆積物薄片の観察から年縞の層厚をもとめ、それを基準にして、2006、2011、2012年にすでに採取している同地点のコアの年縞と比較した結果、年縞の年毎形成が確実に確認された。これは、日本の湖沼では初めてであり、世界でもフィンランドの年縞に次ぐ結果である。 さらに、年縞計数の確実性を検証するために、セシウム-137年代測定を実施した。その結果、一ノ目潟の堆積物では、セシウム-137濃度は、1954年から増加し、1963年に増大ピークを取ることが明らかになった。この変動傾向は、1960年代前半の水爆実験に由来するものと考えられ、一ノ目潟の年縞年代が極めて確度があると証明できた。次に、このように信頼度が高い一ノ目潟の年縞編年のひとつの応用例として、挟在タービダイト層を用いた古地震記録に関する研究をおこなった。一の目潟堆積物には、上方細粒化構造を持つタービダイト層が年縞堆積物中に数多く挟在している。このタービダイト層の成因については,一般的に,洪水,地震,津波,波浪等と諸要因があげられるものの,一の目潟の地形等を考慮に入れると地震によって形成されたものと判断できる。その結果、1910年までの期間において、6枚の上方細粒化構造を持つ単一タービダイト層と、1枚の砂泥互層になっている複合タービダイト層が確認できた。年縞編年に基づくと、単一タービダイト層の形成時期は、上位から西暦1983 年、1964年、1945年、1939年、1935年、および1914年であることが明らかになった。これらの堆積年代と過去100年間における男鹿半島付近で起きたマグニチュード6.0以上の巨大地震を比べると、その多くが対応していることがわかり、1983年5月26日の昭和58年日本海中部地震(M7.7)、1964年5月7日の男鹿半島沖地震(M6.9)、1939年5月1日の男鹿地震(M6.8)、1914年3月15日の強首地震(M7.1)と確実に対応していることが明らかになった。つまり、一ノ目潟の年縞堆積物では、日本海東縁部秋田沖の海底地震や、内陸部で浅い深度を震源とする地震を推定できることが示唆された。さらに、タービダイト層の層厚と震度の関係を検討した結果、一ノ目潟において最も揺れ(震度)が大きかった1939年の男鹿地震では、タービダイト層の層厚が最も厚くなっている。このことから、タービダイト層の層厚から強震強度などを復元することができる可能性がある。一方、1916 年に堆積した複合タービダイト層は,同年ごろに行われていた農業用の取水トンネル工事の影響によるものである。このように一ノ目潟の年縞編年によって復元した堆積物記録は,歴史記録と一対一で対応していることが明白である。今後、有史以前に環境変動を高精度に読み解く可能性が秘められている。

  • 古気候プロキシーとしての湖沼堆積物中の生物源シリカ量の評価

    2012  

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    本研究では、滋賀県琵琶湖および秋田県一の目潟において過去数百年の湖沼堆積物の高時間分解能な生物源シリカ量変化を求め、各調査地点の最近場所気象観測データと照らし合わせることで、生物源シリカ量が何の気象要素に起因して変化するのか解明することを最終的な目的とした。この研究を遂行するため、まず計画通り現地でのコアリング調査を計画し実行した。調査は2か所で実施した。ひとつは、2012年7月1日から4日にかけて琵琶湖(滋賀県)北部湖盆の高島沖(水深70 m地点)にて、他方は2012年8月5日から8日にかけて一の目潟(秋田県)中央部(水深45 m)である。両湖沼とも、それぞれリミノスグラビティーサンプラーを用いて、表層約40cm程度の表層堆積物を採取して、粉末ドライアイスを用いて急速凍結させた未擾乱コアを各湖沼で3本ずつ採取した。これら凍結試料は、高時間分解能な試料分析を行うために、大学実験室に持ち帰り、5mm幅での切断を行った。しかしながら、ここで大きな問題点が生じた。それは、この切断に関して、従来考えていた一般的なのこぎりを用いた切断ではできないことである。そのため、試料分析のステップに行く前に、テスト凍結サンプルを用いて、様々な切断方法、すなわちのこぎりのほか、カンナ、電熱カッター、超音波カッター等を試し、切断の容易さ及び正確さをテストした。その結果、最終的には、スチロールカッターに熱伝導度が高い銅線をつなげて、熱で溶かしながら試料切断する方法が最も優れていることがわかった。以上のような実験を経て、琵琶湖および一ノ目潟で採取した試料の切断を行った。現在、堆積年代の測定のためにPb-210およびCs-137の測定を、一方、生物源シリカ量を測定するために試料のモリブデンイエロー法を測定している。しかしながら、上述した切断に関する事項で、当初の予定したスケジュールが遂行できないため、すべてのコアについてまだ、分析を終えることができていない。そのため、当初予定していた分析データと観測データの対比を十分に行うことができていない。今後、早い段階で、現在進行形の分析を終わらせるともに、観測データとの対比検討のための、データ解析を行い、当初の目的のための成果を出していく予定である。

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