Articles on SPEPS
22.Earth, Isotopes and Organics
This special issue highlights the latest scientific findings in the issues and key words of “Earth, Isotopes and Organics.” The Earth harbors the diverse elements that make up organic molecules with Carbon (C), Hydrogen (H), Nitrogen (N), Oxygen (O), Sulfur (S), and Phosphorus (P). Major inorganic elements represented by magnesium (Mg) and iron (Fe) also have important roles for biosphere. Those diverse elements have also stable and radioactive isotopes in their natural compositions. Standardization through international standard references is underway to develop highly accurate and precise analytical methodology. These highly precise isotope measurements are robust chemical tools in deciphering the interaction between biotic and abiotic factors. Therefore, this special issue can be defined as the understanding of the life science and chemistry on the Earth (e.g., biosphere, hydrosphere, and geosphere) through the representation of essential elements associated with inorganic and organic molecules in nature. In this special issues, further perspectives for state-of-the-art developments in compound-specific isotope analysis will be overviewed for next decadal progresses.
Edited by: Yoshinori Takano, Yoshito Chikaraishi, Thomas Blattmann, Mark Lever, Kensei Kobayashi, Yusuke Okazaki
research: Biogeosciences
Published: March 6, 2025
Magnesium isotopic variation in marine fish organs
Toshihiro Yoshimura, Naoto F. Ishikawa, Nanako O. Ogawa, Soichiro Kusaka, Shigeyuki Wakaki, Tsuyoshi Ishikawa, Kazuya Nagaishi, Masanori Kaneko, Yuta Isaji, Yoshito Chikaraishi, Naohiko Ohkouchi
research: Biogeosciences
Published: February 11, 2025
Distributions of heme B and its implications on Fe biogeochemistry in the eastern Indian Ocean and the western North Pacific Ocean
Yuta Isaji, Koji Sugie, Naoto F. Ishikawa, Nanako O. Ogawa, Kazuhiko Matsumoto, Chisato Yoshikawa, Hajime Obata, Makio C. Honda, Naohiko Ohkouchi
research: Biogeosciences
Published: February 10, 2025
Highly effective energy transfer in the autotroph-heterotroph symbiosis: insights from compound-specific isotope analysis of amino acids
Jincen Li, Mio Shibuya, Yuko Takizawa, Yoshito Chikaraishi
research: Biogeosciences
Published: February 5, 2025
A large elevation in 15N/14N of collagenous amino acids: an insight from starvation experiments of marine organisms
Hyuntae Choi, Yuko Takizawa, Nayeon Park, Yoshito Chikaraishi
research: Biogeosciences
Published: January 29, 2025
Isotope analysis of birds’ eye lens provides early-life information
Emi A. Hasegawa, Jun Matsubayashi, Ichiro Tayasu, Tatsuhiko Goto, Haruka Inoue, Axel G. Rossberg, Chikage Yoshimizu, Masaru Hasegawa, Takumi Akasaka
research: Biogeosciences
Published: January 15, 2025
Differential use of multiple food sources at a bathyal benthic ecosystem in the central Sagami Bay revealed by amino acid nitrogen isotopic compositions
Hidetaka Nomaki, Yoshito Chikaraishi, Nanako O. Ogawa, Koh Maki, Motohiro Shimanaga, Hisami Suga, Masashi Tsuchiya, Toshi Nagata, Naohiko Ohkouchi
research: Biogeosciences
Published: January 3, 2025
Spatiotemporal variations in integrated trophic positions of stream macroinvertebrate communities
Naoto F. Ishikawa, Yoshitoshi Uehara, Takuya Ishida, Tohru Ikeya, Satoshi Asano, Chia-Ying Ko, Tomoya Iwata, Ichiro Tayasu, Naohiko Ohkouchi, Noboru Okuda
research: Biogeosciences
Published: October 2, 2024
Dietary partitioning in sympatric Paradoxurinae civets in Borneo suggested by compound-specific nitrogen isotope analysis of amino acids
Miyabi Nakabayashi, Takumi Tsutaya, Abdul Hamid Ahmad, Yoko Sasaki, Nanako O. Ogawa, Naoto F. Ishikawa, Naohiko Ohkouchi
research: Biogeosciences
Published: September 12, 2024
Natural 14C abundances and stable isotopes suggest discrete uptake routes for carbon and nitrogen in cold seep animals
Hidetaka Nomaki, Shigeaki Kojima, Yosuke Miyairi, Yusuke Yokoyama, Chong Chen
research: Biogeosciences
Published: August 22, 2024
Regulation of nitrogen isotopic ratios of cellular components
Naohiko Ohkouchi, Yuta Isaji, Nanako O. Ogawa