Miyazawa Yoshiyuki

写真a

Title

Associate Professor

Homepage URL

https://hrmonline.schoolbus.jp/yoshi/index_en.html

Profile

Yoshiyuki Miyazawa studied plant ecophysiology during his Master and Ph.D student period in Kyoto University. As a postdoc, he joined ecohydrological and forest meteorological research projects. He contributed to them in data acquisition in the field and data synthesis for the quantification of scalar (CO2 and water vapor) and energy exchange between the vegetation and the atmosphere, in comparison to the independently measured data. He is interested in the physiological and morphological adaptation of plants to the fluctuating environmental conditions, and the quantification of the effects of such adaptation to the stand-scale gas and energy fluxes. Recently he is working to develop novel research instruments that allows multi-point, continuous and high time resolution monitoring of ecophysiological processes of the forest ecosystems at a wide geographical scale.
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Current Affiliation Organization 【 display / non-display 】

  • Duty   University of the Ryukyus   Faculty of Agriculture   Subtropical Agro-Environmental Sciences   Associate Professor  

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University 【 display / non-display 】

  • 1996.01
    -
    2000.03

    Kyoto University   Faculty of Agriculture   Graduated

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Graduate School 【 display / non-display 】

  • 2000.04
    -
    2025.03

    Kyoto University  Graduate School, Division of Agriculture  Department of Forest Science  Doctor's Course  Completed

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Study abroad experiences 【 display / non-display 】

  • 2010.02
    -
    2010.08

    University of Hawaii at Manoa  

  • 2015.04
    -
    2017.03

    University of Hawaii at Manoa  

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Academic degree 【 display / non-display 】

  • Kyoto University -  Ph.D.

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External Career 【 display / non-display 】

  • 2006.04
    -
    2008.03

     

  • 2008.04
    -
    2010.10

    JSPS Research fellow  

  • 2010.11
    -
    2015.03

    Research Institute of East Asia Environment, Kyushu University  

  • 2015.04
    -
    2017.03

    Research fellow  

  • 2017.04
    -
    2025.05

    Kyushu University  

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Affiliated academic organizations 【 display / non-display 】

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    Ecological Society of Japan 

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    American Geophysical Union 

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Research Interests 【 display / non-display 】

  • 森林科学、生態学

  • response to environmental factors

  • sap flow

  • plant ecophysiology

  • photosynthesis

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Research Areas 【 display / non-display 】

  • Leaf- and stand-level gas exchange

  • Environmental responses by cool temperate and subalpine trees

  • Leaf gas exchange characteristics of mangrove trees

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Research Theme 【 display / non-display 】

  • Effects of plant ecophysiological traits on the forests energy and scalar transfer

  • Ecophysiological response of trees to the light and temperature conditions

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Thesis 【 display / non-display 】

  • Photosynthesis and phenology of leaves in woody plants under changing light environments in temperate forests

    2005.03

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Published Papers 【 display / non-display 】

  • Leaf trichomes can alleviate water deficit stress and maintain diurnal photosynthesis by increasing leaf wetness and water absorption in Metrosideros polymorpha

    Amada, G; Miyazawa, Y; Kominami, Y; Kitayama, K; Onoda, Y

    PLANT SPECIES BIOLOGY   41 ( 1 ) 1 - 13   2026.01 [ Peer Review Accepted ]

    Type of publication: Research paper (scientific journal)

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      DOI Open Access

  • Transpiration and plant hydraulics of <i>Abies veitchii</i> under fluctuating environmental conditions in cool montane forest

    Yoshiyuki Miyazawa, Daisuke Sugiura, Taichi Sugiyama, Kojiro Iwamoto, Haruhiko Taneda

    Ecological Research ( Wiley )  40 ( 2 ) 188 - 206   2024.10 [ Peer Review Accepted ]

    Type of publication: Research paper (scientific journal)

    　View Summary

    Abstract In subalpine fir wave forests, strips of dead and weakened trees occur perpendicular to the slope next to strips of healthy trees. To reveal the transpiration by weakened Abies veitchii trees exposed to increased atmospheric evaporative demand, we investigated the ecophysiological traits closely related to the growth and transpiration, comparing them with those of the healthy trees and saplings in the fir wave of Mt. Shimagare in central Japan. The transpiration rate (E) was investigated using sap flux sensors to measure heat pulse velocity and compared with the surrogate for the needle water demand, which was computed using a multilayered gas and energy transfer model (modeled E, E<sub>mod</sub>). Weakened trees exhibited smaller diameter growth and narrower sapwood than healthy trees, as well as lower heat pulse velocity compared with healthy saplings. However, needle‐level traits did not differ significantly between weakened and healthy trees. Needle water potential at midday was as negative as the needle turgor loss point, and the measured heat pulse velocity increased linearly with E<sub>mod</sub> but leveled off above a certain E<sub>mod</sub> value in weakened trees and healthy saplings, suggesting that trees restricted E to balance the needle water budget. Heat pulse velocity of weakened trees leveled off at E<sub>mod</sub> lower than that of healthy saplings, probably due to lower capacity for water supply to the needles. Restriction of E would occur less frequently but be necessary for both weakened and healthy A. veitchii on Mt. Shimagare to avoid hydraulic failure, sacrificing photosynthetic carbon assimilation.

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      DOI Open Access

  • Microcontroller-based water control system for evaluating crop water use characteristics

    Daisuke Sugiura, Shiro Mitsuya, Hirokazu Takahashi, Ryo Yamamoto, Yoshiyuki Miyazawa

    Plant Methods ( Springer Science and Business Media LLC )  20 ( 1 ) 179 - 179   2024.05 [ Peer Review Accepted ]

    Type of publication: Research paper (scientific journal)

    　View Summary

    <title>Abstract</title> <bold>Background</bold> Climate change and the growing demand for agricultural water threaten global food security. Understanding water use characteristics of major crops from leaf to field scale is critical, particularly for identifying crop varieties with enhanced water-use efficiency (WUE) and stress tolerance. Traditional methods to assess WUE are either by gas exchange measurements at the leaf level or labor-intensive manual pot weighing at the whole-plant level, both of which have limited throughput.<bold>Results</bold> Here, we developed a microcontroller-based low-cost system that integrates pot weighing, automated water supply, and real-time monitoring of plant water consumption via Wi-Fi. We validated the system using major crops (rice soybean, maize) under diverse stress conditions (salt, waterlogging, constant drought). Salt-tolerant rice maintained higher water consumption and growth under salinity than salt-intolerant rice. Waterlogged soybean exhibited reduced water use and growth. Long-term experiments revealed significant WUE differences between rice varieties and morphological adaptations represented by altered shoot-to-root ratios under constant drought conditions in maize.<bold>Conclusions</bold> We demonstrate that the system can be used for varietal differences between major crops in their response to drought, waterlogging, and salinity stress. This system enables high-throughput, long-term evaluation of water use characteristics, facilitating the selection and development of water-saving and stress-tolerant crop varieties.

  • Generation of sprouts and growth of remaining shoots in multi-stem Quercus glauca individuals after stem thinning.

    渡部颯太, 作田耕太郎, 宮沢良行

    九州森林研究   ( 77 )   2024 [ Peer Review Accepted ]

    Type of publication: Research paper (other science council materials etc.)

  • Implications of seasonal changes in photosynthetic traits and leaf area index for canopy CO2 and H2O fluxes in a Japanese cedar <i>(Cryptomeria japonica</i> D. Don) plantation

    Yoshiaki Hata, Tomo'omi Kumagai, Takanori Shimizu, Yoshiyuki Miyazawa

    ECOLOGICAL MODELLING   477   2023.03 [ Peer Review Accepted ]

    Type of publication: Research paper (scientific journal)

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      DOI

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Other Papers 【 display / non-display 】

  • Introduction of digital devices for the monitoring of plant ecophysiology

    宮沢良行, 杉浦大輔

    日本生態学会大会講演要旨(Web)   71st   2024

     

    J-GLOBAL

  • Elucidation of water physiological status of spruce for natural restoration of declined forest on Mt. Ohdaigahara -Research Group for Natural Restoration of Declined Spruce Forest on Mt. Ohdaigahara-

    木佐貫博光, 熊谷朝臣, 宮沢良行, 岡本榛名

    自然保護助成基金助成成果報告書(Web)   28   2020

     

    J-GLOBAL

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Presentations 【 display / non-display 】

  • 干潟のマングローブの蒸散特性

    宮沢良行

    日本森林学会大会学術講演集  2023.05  -  2023.05 

  • 関東および九州のスギ・ヒノキ林での観測に基づく水利用効率の季節変化

    清水 貴範, 清水 晃, 飯田 真一, 小林 政広, 玉井 幸治, 石塚 成宏, 宮沢 良行, 壁谷 直記, 熊谷 朝臣

    日本森林学会大会発表データベース  2023.05  -  2023.05 

  • 萌芽枝整理が行われたアラカシ株立ち個体の樹液流速の変動

    渡部 颯太, 作田 耕太郎, 宮沢 良行

    日本森林学会大会発表データベース  2023.05  -  2023.05 

  • Development of the method for estimating water consumption of C<sub>3</sub>,C<sub>4</sub> crops using Micro heat ratio sensor

    小島渚, 宮沢良行, 杉浦和彦, 杉浦大輔

    日本作物学会講演会要旨集  2023.03  -  2023.03 

  • 萌芽枝整理された根株移植個体の樹液流速

    Sota Watanabe, Kotaro Sakuta, Yoshiyuki Miyazawa

    日本森林学会大会発表データベース  2022.05  -  2022.05 

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Grant-in-Aid for Scientific Research 【 display / non-display 】

  • Development of a new evaluation system for source and sink capacity in rice canopy

    Grant-in-Aid for Scientific Research(B)

    Project Year: 2023.04  -  2026.03 

    Direct: 14,600,000 (YEN)  Overheads: 18,980,000 (YEN)  Total: 4,380,000 (YEN)

  • Grant-in-Aid for Scientific Research(B)

    Project Year: 2022.04  -  2026.03 

    Direct: 13,200,000 (YEN)  Overheads: 17,160,000 (YEN)  Total: 3,960,000 (YEN)

  • An investigation for population maintenance mechanisms in Nemalionopsis shawii, an endangered freshwater red alga in Japan

    Grant-in-Aid for Scientific Research(C)

    Project Year: 2022.04  -  2025.03 

    Direct: 3,200,000 (YEN)  Overheads: 4,160,000 (YEN)  Total: 960,000 (YEN)

  • Ecophysiological study on tree mortality of conifer trees in a fir wave

    Grant-in-Aid for Scientific Research(B)

    Project Year: 2021.04  -  2025.03 

    Direct: 10,700,000 (YEN)  Overheads: 13,910,000 (YEN)  Total: 3,210,000 (YEN)

  • Ecophysiological study on tree mortality of conifer trees in a fir wave

    Grant-in-Aid for Scientific Research(B)

    Project Year: 2021.04  -  2025.03 

    Direct: 10,700,000 (YEN)  Overheads: 13,910,000 (YEN)  Total: 3,210,000 (YEN)

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