Sensitive determination of nanomolar urea and its dynamics in oligotrophic ocean

• Project/Area Number: 17H01852
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Environmental dynamic analysis
• Research Institution: Tokyo University of Marine Science and Technology
• Principal Investigator: Hashihama Fuminori 東京海洋大学, 学術研究院, 准教授 (80535807)
• Co-Investigator(Kenkyū-buntansha): 神田 穣太 東京海洋大学, 学術研究院, 教授 (60202032)
• Project Period (FY): 2017-04-01 – 2022-03-31
• Project Status: Completed (Fiscal Year 2021)
• Budget Amount: ¥17,290,000 (Direct Cost: ¥13,300,000、Indirect Cost: ¥3,990,000); Fiscal Year 2021: ¥2,990,000 (Direct Cost: ¥2,300,000、Indirect Cost: ¥690,000); Fiscal Year 2020: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000); Fiscal Year 2019: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000); Fiscal Year 2018: ¥3,640,000 (Direct Cost: ¥2,800,000、Indirect Cost: ¥840,000); Fiscal Year 2017: ¥3,640,000 (Direct Cost: ¥2,800,000、Indirect Cost: ¥840,000)
• Keywords: 海洋科学 / 環境分析 / 尿素 / 亜熱帯海域

Outline of Final Research Achievements

This study investigated whether urea is a major nitrogen source for sustaining net communiy production in the oligotrophic ocean, using a newly-developed sensitive analytical system for determining trace urea. In the nitrate-depleted subtropical ocean, urea existed at nanomolar level and was utilized by microbes as revealed by urease gene analysis and urea-15N uptake experiment. However, annual budget analysis of various nitrogen components demonstrated that net community production was sustained by not only urea but also other dissolved organic nitrogen.

Academic Significance and Societal Importance of the Research Achievements

貧栄養な亜熱帯海域の純群集生産（光合成による正味の二酸化炭素吸収）を駆動する窒素源としてこれまで見過ごされてきた尿素の寄与を評価することに成功した。尿素が微生物群集に利用されている実態を捉えることに成功したが、年間の純群集生産の駆動源としては尿素だけでなく他の溶存有機態窒素も大きく寄与していることを示すことができた。微生物群集による窒素の利用は二酸化炭素から有機物をつくる光合成を支えるものであり、本研究の成果は地球上の二酸化炭素収支の仕組みを理解する上で重要な知見となる。

Research Products

• [Int'l Joint Research] University of Tasmania(オーストラリア)
• [Int'l Joint Research] Hong Kong Univ. Sci. Tech.(中国)
• [Int'l Joint Research] University of Tasmania(オーストラリア)
• [Int'l Joint Research] Plymouth Marine Laboratory(英国)
• [Journal Article] Phytoplankton dynamics as a response to physical events in the oligotrophic Eastern Indian Ocean (2022)
  • Author(s): Siyu Jiang, Fuminori Hashihama, Yukio Masumoto, Hongbin Liu, Hiroshi Ogawa, Hiroaki Saito
  • Journal Title: Progress in Oceanography Volume: 203 Pages: 102784-102784
  • DOI: 10.1016/j.pocean.2022.102784
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Decadal vision in oceanography 2021: Mid-latitude ocean (2021)
  • Author(s): 橋濱史典・纐纈慎也・近藤能子・佐々木克徳・杉本周作・高橋一生・長井健容・西岡純・林田博士・平井淳也
  • Journal Title: Oceanography in Japan Volume: 30 Issue: 5 Pages: 127-154
  • DOI: 10.5928/kaiyou.30.5_127
  • NAID: 130008131961
  • ISSN: 0916-8362, 2186-3105
  • Year and Date: 2021-11-15
  • Peer Reviewed / Open Access
• [Journal Article] Nanomolar phosphate supply and its recycling drive net community production in the subtropical North Pacific (2021)
  • Author(s): Hashihama Fuminori、Yasuda Ichiro、Kumabe Aki、Sato Mitsuhide、Sasaoka Hiroshi、Iida Yosuke、Shiozaki Takuhei、Saito Hiroaki、Kanda Jota、Furuya Ken、Boyd Philip W.、Ishii Masao
  • Journal Title: Nature Communications Volume: 12 Issue: 1 Pages: 3462-3462
  • DOI: 10.1038/s41467-021-23837-y
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Regionally variable responses of nitrogen fixation to iron and phosphorus enrichment in the Pacific Ocean (2021)
  • Author(s): Iwao Tanita, Takuhei Shiozaki, Taketoshi Kodama, Fuminori Hashihama, Mitsuhide Sato, Kazutaka Takahashi, Ken Furuya
  • Journal Title: Journal of Geophysical Research: Biogeosciences Volume: 126 Issue: 9 Pages: 1-13
  • DOI: 10.1029/2021jg006542
  • Peer Reviewed / Open Access
• [Journal Article] Assimilation and oxidation of urea‐derived nitrogen in the summer Arctic Ocean (2021)
  • Author(s): Shiozaki Takuhei、Hashihama Fuminori、Endo Hisashi、Ijichi Minoru、Takeda Noriko、Makabe Akiko、Fujiwara Amane、Nishino Shigeto、Harada Naomi
  • Journal Title: Limnology and Oceanography Volume: 66 Issue: 12 Pages: 4159-4170
  • DOI: 10.1002/lno.11950
  • Peer Reviewed
• [Journal Article] Cross-basin differences in the nutrient assimilation characteristics of induced phytoplankton blooms in the subtropical Pacific waters (2021)
  • Author(s): Fuminori Hashihama, Hiroaki Saito, Taketoshi Kodama, Saori Yasui-Tamura, Jota Kanda, Iwao Tanita, Hiroshi Ogawa, E. Malcolm S. Woodward, Philip W. Boyd, Ken Furuya
  • Journal Title: Biogeosciences Volume: 18 Issue: 3 Pages: 897-915
  • DOI: 10.5194/bg-18-897-2021
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Phytoplankton growth and grazing mortality through the oligotrophic subtropical North Pacific (2021)
  • Author(s): Siyu Jiang, Fuminori Hashihama, Hiroaki Saito
  • Journal Title: Journal of Oceanography Volume: in press Issue: 3 Pages: 505-521
  • DOI: 10.1007/s10872-020-00580-4
  • NAID: 40022579312
  • Peer Reviewed
• [Journal Article] Biogeochemical controls of particulate phosphorus distribution across the oligotrophic subtropical Pacific Ocean (2020)
  • Author(s): Fuminori Hashihama, Hiroaki Saito, Takuhei Shiozaki, Makoto Ehama, Shuhei Suwa, Takanori Sugiyama, Haruka Kato, Jota Kanda, Mitsuhide Sato, Taketoshi Kodama, Tamaha Yamaguchi, Sachiko Horii, Iwao Tanita, Shota Takino, Kazutaka Takahashi, Hiroshi Ogawa, Philip W. Boyd, Ken Furuya
  • Journal Title: Global Biogeochemical Cycles Volume: 34 Issue: 9
  • DOI: 10.1029/2020gb006669
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Biological nitrogen fixation detected under Antarctic sea ice (2020)
  • Author(s): Shiozaki Takuhei、Fujiwara Amane、Inomura Keisuke、Hirose Yuu、Hashihama Fuminori、Harada Naomi
  • Journal Title: Nature Geoscience Volume: 13 Issue: 11 Pages: 729-732
  • DOI: 10.1038/s41561-020-00651-7
  • Peer Reviewed / Open Access
• [Journal Article] Automated simultaneous determination of total dissolved nitrogen and phosphorus in seawater by persulfate oxidation method (2020)
  • Author(s): Saori Yasui-Tamura, Fuminori Hashihama, Hiroshi Ogawa, Takashi Nishimura, Jota Kanda
  • Journal Title: Talanta Open Volume: 2 Pages: 100016-100016
  • DOI: 10.1016/j.talo.2020.100016
  • Peer Reviewed / Open Access
• [Journal Article] Automated colorimetric determination of nanomolar urea in seawater by gas-segmented continuous flow analysis using a liquid waveguide capillary cell (2020)
  • Author(s): Noriko Takeda, Fuminori Hashihama, Jota Kanda
  • Journal Title: Talanta Volume: 208 Pages: 120371-120371
  • DOI: 10.1016/j.talanta.2019.120371
  • Peer Reviewed
• [Journal Article] Assessment of potential phagotrophy by pico- and nanophytoplankton in the North Pacific Ocean using flow cytometry (2019)
  • Author(s): Mitsuhide Sato, Fuminori Hashihama
  • Journal Title: Aquatic Microbial Ecology Volume: 82 Issue: 3 Pages: 275-288
  • DOI: 10.3354/ame01892
  • Peer Reviewed
• [Journal Article] Linkage Between Dinitrogen Fixation and Primary Production in the Oligotrophic South Pacific Ocean (2018)
  • Author(s): Shiozaki Takuhei、Bombar Deniz、Riemann Lasse、Sato Mitsuhide、Hashihama Fuminori、Kodama Taketoshi、Tanita Iwao、Takeda Shigenobu、Saito Hiroaki、Hamasaki Koji、Furuya Ken
  • Journal Title: Global Biogeochemical Cycles Volume: 32 Issue: 7 Pages: 1028-1044
  • DOI: 10.1029/2017gb005869
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Stable isotopic evidence for differential contribution of diazotrophs to the epipelagic grazing food chain in the mid-Pacific Ocean (2018)
  • Author(s): Horii, S., K. Takahashi, T. Shiozaki, F. Hashihama, & K. Furuya
  • Journal Title: Global Ecology and Biogeography Volume: 27 Issue: 12 Pages: 1467-1480
  • DOI: 10.1111/geb.12823
  • Peer Reviewed
• [Journal Article] Basin scale variability of active diazotrophs and nitrogen fixation in the North Pacific, from the tropics to the subarctic Bering Sea (2017)
  • Author(s): Shiozaki Takuhei、Bombar Deniz、Riemann Lasse、Hashihama Fuminori、Takeda Shigenobu、Yamaguchi Tamaha、Ehama Makoto、Hamasaki Koji、Furuya Ken
  • Journal Title: Global Biogeochemical Cycles Volume: 31 Issue: 6 Pages: 996-1009
  • DOI: 10.1002/2017gb005681
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Basin-scale distribution of NH4+ and NO2- in the Pacific Ocean (2017)
  • Author(s): Yasunaka Sayaka、Nojiri Yukihiro、Hashioka Taketo、Yoshikawa Chisato、Kodama Taketoshi、Nakaoka Shin-ichiro、Chiba Sanae、Hashihama Fuminori、Wakita Masahide、Furuya Ken、Sasano Daisuke、Murata Akihiko、Uchida Hiroshi、Aoyama Michio
  • Journal Title: Journal of Oceanography Volume: 74 Issue: 1 Pages: 1-11
  • DOI: 10.1007/s10872-017-0433-1
  • Peer Reviewed / Open Access
• [Presentation] Effect of geographical variation in primary productivity and nitrogen fixation on mesopelagic fish community in the subtropical North Pacific (2021)
  • Author(s): Yutaro Nagatomo, Sachiko Horii, Junya Hirai, Fuminori Hashihama, Tetsuya Sado, Tekehiko Fukuchi, Masaki Miya, Kazutaka Takahashi
  • Organizer: ASLO Aquatic Science Meeting
  • Int'l Joint Research
• [Presentation] Nitrogen fixation and diazotroph community structure in the eastern Indian Ocean (2021)
  • Author(s): Sato Takuya, Shiozaki Takuhei, Fuminori Hashihama, Toshihiko Takemura, Kazutaka Takahashi
  • Organizer: ASLO Aquatic Science Meeting
  • Int'l Joint Research
• [Presentation] Transient phytoplankton blooms and their formation mechanisms in oligotrophic subtropical and tropical oceans (2021)
  • Author(s): Siyu Jiang, Fuminori Hashihama, Yukio Masumoto, Hongbin Liu, Hiroshi Ogawa, Hiroaki Saito
  • Organizer: IMBER West Pacific Symposium 2021
  • Int'l Joint Research
• [Presentation] Temporary phytoplankton bloom induced by physical disturbances in the Eastern Indian Ocean (2021)
  • Author(s): Siyu Jiang・Fuminori Hashihama・Hiroaki Saito
  • Organizer: 日本地球惑星科学連合
• [Presentation] 海洋学の10年展望2021：中緯度 (2021)
  • Author(s): 橋濱史典・纐纈慎也・近藤能子・佐々木克徳・杉本周作・高橋一生・長井健容・西岡純・林田博士・平井淳也
  • Organizer: 日本海洋学会創立80周年記念シンポジウム
  • Invited
• [Presentation] 北太平洋亜熱帯域の純群集生産を駆動するナノモルレベルのリン供給と迅速な再生 (2021)
  • Author(s): 橋濱史典・安田一郎・隈部あき・佐藤光秀・笹岡洋志・飯田洋介・塩崎拓平・齊藤宏明・神田穣太・古谷研・Philip W. Boyd・石井雅男
  • Organizer: 日本海洋学会
• [Presentation] Temporary phytoplankton blooms in oligotrophic subtropical and tropical ocean (2021)
  • Author(s): 江思宇・橋濱史典・齊藤宏明
  • Organizer: 日本海洋学会海洋生物研究会海洋生物シンポジウム
• [Presentation] なぜTrichodesmium spp.は群体を形成するのか？：VPRによる鉛直分布観察結果から考える適応的意義 (2021)
  • Author(s): 由井智啓・堀井幸子・橋濱史典・筧 茂穂・高橋一生
  • Organizer: 日本海洋学会海洋生物研究会海洋生物シンポジウム
• [Presentation] Nanomolar nutrient dynamics in the oligotrophic subtropical ocean (2020)
  • Author(s): Fuminori Hashihama
  • Organizer: IMAS-CSIRO BGC Discussion Group Meeting
  • Int'l Joint Research / Invited
• [Presentation] Biological nitrogen fixation detected under Antarctic sea ice (2020)
  • Author(s): Takuhei Shiozaki, Amane Fujiwara, Keisuke Inomura, Yuu Hirose, Fuminori Hashihama, Naomi Harada
  • Organizer: Symposium on Polar Science
  • Int'l Joint Research
• [Presentation] Distribution and isotopic composition of N2O in the eastern Indian Ocean (2020)
  • Author(s): Sakae Toyoda・Kotaro Terajima・Naohiro Yoshida・Chisato Yoshikawa・Akiko Makabe・Fuminori Hashihama・Hiroshi Ogawa
  • Organizer: 日本地球惑星科学連合 (JpGU-AGU Joint Meeting)
• [Presentation] Temporary phytoplankton biomass increases in oligotrophic subtropical and tropical oceans (2020)
  • Author(s): 江思宇・橋濱史典・齊藤宏明
  • Organizer: 日本海洋学会
• [Presentation] 南極海海氷域における窒素固定の発見 (2020)
  • Author(s): 塩崎拓平・藤原周・井之村啓介・広瀬侑・橋濱史典・原田尚美
  • Organizer: 日本海洋学会
• [Presentation] 東部インド洋における窒素固定者群集構造と窒素固定活性の関係 (2020)
  • Author(s): 佐藤拓哉・塩崎拓平・橋濱史典・高橋一生
  • Organizer: 日本海洋学会海洋生物研究会海洋生物シンポジウム
• [Presentation] Comparison of phytoplankton growth and mortality in oligotrophic subtropical North Pacific and Eastern Indian Ocean (2019)
  • Author(s): Siyu Jiang, Fuminori Hashihama, Hiroaki Saito
  • Organizer: PICES annual meeting
  • Int'l Joint Research
• [Presentation] ナノモルレベル栄養塩類の分布と今後の展望 (2019)
  • Author(s): 橋濱史典
  • Organizer: 東京大学大気海洋研究所共同利用研究集会「白鳳丸30周年記念世界一周航海 (HEAW30) へ向けた研究戦略会議」
  • Invited
• [Presentation] 貧栄養海域における尿素と無機窒素栄養塩類の地理的変動 (2019)
  • Author(s): 武田典子・橋濱史典・塩崎拓平・佐藤拓哉・高橋一生・安井沙織・神田穣太
  • Organizer: 日本海洋学会
• [Presentation] 東部インド洋熱帯・亜熱帯外洋域における魚類マイクロネクトン群集の分布と変動要因 (2019)
  • Author(s): 長友佑太朗・佐藤拓哉・Zhou Fanyu・一戸凌・平井惇也・西部裕一郎・橋濱史典・高橋一生
  • Organizer: 日本海洋学会
• [Presentation] 東部インド洋における窒素固定活性の南北勾配 (2019)
  • Author(s): 佐藤拓哉・塩崎拓平・橋濱史典・武田典子・佐藤光秀・高橋一生
  • Organizer: 日本海洋学会
• [Presentation] 長光路吸光光度分析法を用いた全粒状窒素・リンの高感度計測 (2019)
  • Author(s): 佐々木里樹・橋濱史典・武田典子・神田穣太
  • Organizer: 日本海洋学会
• [Presentation] 北太平洋亜熱帯域におけるProchlorococcusのウレアーゼ遺伝子発現 (2019)
  • Author(s): 岡戸創・塩崎拓平・佐藤光秀・堀井幸子・山口珠葉・佐藤拓哉・高橋一生・濵崎恒二・武田典子・杉山貴紀・加藤遥・安井沙織・神田穣太・橋濱史典
  • Organizer: 日本海洋学会海洋生物研究会海洋生物シンポジウム
• [Presentation] 北太平洋外洋域における混合栄養性マイクロプランクトンの地理分布と環境要因との関連 (2019)
  • Author(s): 高野永実子・堀井幸子・仲村康秀・橋濱史典・高橋一生
  • Organizer: 日本海洋学会海洋生物研究会海洋生物シンポジウム
• [Presentation] Nutrient front across the Kuroshio (2018)
  • Author(s): Hiroaki Saito, Fuminori Hashihama, Yu Umezawa, Ryu Nozaki, Hiroshi Ogawa, Hideki Fukuda
  • Organizer: International Symposium: Understanding Changes in Transitional Areas of the Pacific (PICES)
  • Int'l Joint Research
• [Presentation] Microzooplankton selective grazing on phytoplankton in the subtropical North Pacific Ocean (2018)
  • Author(s): Siyu Jiang, Fuminori Hashihama, Hiroaki Saito
  • Organizer: 8th China-Japan-Korea IMBER Symposium
  • Int'l Joint Research
• [Presentation] Transpaficic distribution of micronektonic fish community in the subtropical open water (2018)
  • Author(s): Yutaro Nagatomo, Kazutaka Takahashi, Tetsuya Sado, Masaki Miya, Fuminori Hashihama, Sachiko Horii, Junya Hirai
  • Organizer: PICES annual meeting
  • Int'l Joint Research
• [Presentation] The role of ammonium excretion of small planktonic copepods in epipelagic nitrogen cycle in the subtropical North Pacific Ocean (2018)
  • Author(s): Ken-ichi Nakamura, Kazutaka Takahashi, Fuminori Hashihama, Ken Furuya
  • Organizer: PICES annual meeting
  • Int'l Joint Research
• [Presentation] Microzooplankton selective grazing on phytoplankton in the subtropical North Pacific Ocean (2018)
  • Author(s): Siyu Jiang, Fuminori Hashihama, Hiroaki Saito
  • Organizer: PICES annual meeting
  • Int'l Joint Research
• [Presentation] 海水中の尿素の高感度自動分析法の開発 (2018)
  • Author(s): 武田典子・橋濱史典・神田穣太・石井雅男
  • Organizer: 日本海洋学会
• [Presentation] 湿式酸化分解法による海水中の全溶存窒素・リンの全自動分析 (2018)
  • Author(s): 安井沙織・橋濱史典・西村崇・小川浩史・神田穣太
  • Organizer: 日本海洋学会
• [Presentation] Contribution of diazotrophs to the epipelagic grazing food chain in the subtropical mid-Pacific (2018)
  • Author(s): Ken Furuya, Sachiko Horii, Kazutaka Takahashi, Takuhei Shiozaki, Fuminori Hashihama
  • Organizer: Ocean Science Meeting
  • Int'l Joint Research
• [Presentation] 西部北太平洋亜熱帯域における栄養塩環境と植物プランクトン群集の季節変動 (2017)
  • Author(s): 橋濱史典・隈部あき・笹岡洋志・羽住彩花・石井雅男・佐藤光秀
  • Organizer: 日本海洋学会
• [Presentation] Biological nitrogen fixation sustains fishery production in the subtropical Pacific Ocean (2017)
  • Author(s): Sachiko Horii, Kazutaka Takahashi, Natsuki Gonda, Takuhei Shiozaki, Junji Yonezawa, Kazuto Andoh, Ichiro Komazawa, Fuminori Hashihama, Ken Furuya
  • Organizer: 日本地球惑星科学連合
• [Remarks] プレスリリース：海の砂漠の謎に迫る！ －ほんのわずかなリンの供給が活発な生物生産を駆動－
  • URL: https://www.kaiyodai.ac.jp/topics/img/c263d0645387382174724494a6ba76ec.pdf