Faculty Profiles - KITAGAWA, Hiroyuki

Papers - KITAGAWA, Hiroyuki

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*Radiocarbon concentration of lake sediment cellulose from Lake Erhai in southwest China Reviewed

H. Kitagawa, S. M. Tareq, H. Matsuzaki, N. Inoue, E. Tanoue and Y. Yasuda

Nucl. Instr. and Meth. in Phys. Res. B Vol. 259 page： 526–529 2007

Authorship：Lead author Language：English Publishing type：Research paper (scientific journal)

To improve age models for lake sediment cores without suitable 14C dating materials such as terrestrial plant fossils, we investigated the radiocarbon dating of lake sediment cellulose. The cellulose fraction in the sediments was obtained by a sequential decomposition of other organic matter, and subsequently dated by AMS. In general, 14C ages of the lake sediment cellulose obtained from a 10-m sediment core from Lake Erhai on the Yunnan-Guizhou Plateau are in agreement with 14C dates from terrestrial plant fossils. For the early Holocene, however, differences of up to 1000 14C years are observed between lake sediment cellulose and terrestrial plant fossils. This disagreement is probably caused by the contribution of 14C-depleted cellulose synthesized by aquatic plants/algae in the lake. To obtain a precise

Magnesium isotope analysis of different chlorophyll forms in marine phytoplankton using multi-collector ICP-MS Reviewed

K. Ra and H. Kitagawa

J. Anal. At. Spectrom. Vol. 22 page： 817-821 2007

Language：English Publishing type：Research paper (scientific journal)

A new separation method of magnesium in the different chlorophyll forms, including chlorophyll a, b, c1 + c2 and c3, of phytoplankton, was developed for isotope measurements. Our method is based on a two-step separation using HPLC and a C18 column. The method made it possible to determine the magnesium isotopes (d25Mg and d26Mg) of the particular chlorophyll forms in marine living phytoplankton with a high precision using a multi-collector ICP-MS. The differences of d26Mg values among commercial chlorophylls (four types of chlorophyll a and two types of chlorophyll b) and the different chlorophyll forms of marine diatom-rich phytoplankton collected from the Northwest Pacific show variations of 1.5% and 0.65%, respectively. We found a slight enrichment in the heavier magnesium isotopes in chlorophylls relative to sea-water: 0.58%, 0.74%, 0.27% and 0.35% on d26Mg for chlorophyll a, b, c1 + c2 and c3, respectively. Our data suggest a mass dependent fractionation of magnesium isotopes among species of photosynthetic organisms and the chlorophyll forms. The magnesium isotope analysis by chlorophyll forms might not only give a new insight into the biosynthetic pathways associated with chlorophylls but also be a potential environmental indicator preserved in marine phytoplankton and other photosynthetic organisms.

Environmental Magnetic Record and Paleosecular Variation Data for the Last 40 Kyrs from Lake Biwa Sediments, Central Japan. Reviewed

A. Hayashida, M. Ali, Y. Kuniko, H. Kitagawa, M. Torii, K. Takemura

Earth, Planets and Space Vol. 59 page： 807-814 2007

Tropical South China Sea Surface 14C record in an annually-banded coral Reviewed

T. Mitsuguchi, Dang, X. Phong, H. Kitagawa, M. Yoneda and Y. Shibata

Radiocarbon Vol. 47 ( 2 ) 2007

Variation of solar cyclicity during the Spoerer Minimum Reviewed

H. Miyahara, K. Masuda, Y. Muraki, H. Kitagawa and T. Nakamura

J. of Geophysical Research (Space Physics) Vol. 111 ( A3 ) page： A03103 2006.3

Sr/Ca ratio of Porites coral from Con Dao Island, South of Vietnam Reviewed

Dang, X. Phong, T. Mitsuguchi, H. Kitagawa, T. Uchida and Y. Shibata

Proc. of 10th Int'l Coral Reef Symposium page： 567-571 2006

Seasonally specific responses of the East Asian monsoon to deglacial climate changes Reviewed

T. Nakagawa, P. E. Tarasov, H. Kitagawa, Y. Yasuda and K. Gotanda

Geology Vol. 34 ( 7 ) page： 521-524 2006

Language：English Publishing type：Research paper (scientific journal)

The deglacial meltwater pulse in the North Atlantic that induced the Younger Dryas event also prompted climate cooling in East Asian monsoon regions such as Japan and coastal mid latitude China. However, very little is understood about the mechanism that can transmit changes in the North Atlantic to the Far East. Here we show that the shutdown of the North Atlantic thermohaline circulation brought about significantly lower temperatures and higher precipitation in the Japanese winter, whereas the change in the Japanese summer climate was considerably smaller. The cooling of the Siberian air mass seems to have caused an increased pressure gradient between Siberia and the West Pacific in winter, intensifying the winter monsoon. The Mongolian high pressure system and the westerly jet stream played an important role in the teleconnection. In contrast, the warming at the onset of the late glacial interstadial (GI-1; Bølling-Allerød) in the West Pacific did not have season-specific features, implying that the principal driving mechanism of this warming event may lie in a panhemispheric or global factor, such as insolation changes.

Seasonal changes of alkaline dust aerosol and its climatic influencing factors in western Songnen Plain, North-east China Reviewed

B. Chen, H, Ke, J. Dong-mei, H. Kitagawa and F. Li

Acta Scientiae Circumstantiae Vol. 26 ( 3 ) page： 521-527 2006

Pollen/event stratigraphy of the varved sediment of Lake Suigetsu, central Japan from 15,701 to 10,217 SG vyr BP (Suigetsu varve years before present): Description, interpretation, and correlation with other regions Reviewed

T. Nakagawa, H. Kitagawa, Y. Yasuda, P. E. Tarasov, K. Gotanda and Y. Sawai

Quaternary Science Reviews Vol. 24 page： 1691–1701 2005

Eolian quartz flux variations in Cheju Island, Korea, during the last 6500 yr and a possible Sun–monsoon linkage Reviewed

J. Lim, E. Matsumoto and H. Kitagawa

Quaternary Research Vol. 64 page： 12–20 2005

韓国南東部・蔚山断層の古地　震活動－慶州市葛谷里における第2次トレンチ調査－ Reviewed

木康弘・岡田篤正・竹村恵二・慶　在福・廣内大助・金　幸隆・伊藤　愛・大石　超・中村洋介・成瀬敏郎・北川浩之・渡辺満久

活断層研究 Vol. 25 page： 147-152 2005

Late Quaternary faulting along the western margin of the Poronaysk Lowland in central Sakhalin, Russia Reviewed

H. Tsutsumi, Y. Suzuki, A. I. Kozhurin, M. I. Strel'tsov, T. Ueki, H. Goto, K. Okumura, R. F. Bulgakov and H. Kitagawa

Tectonophysics Vol. 407 page： 257-268 2005

The earliest record of major anthropogenic deforestation in the Ghab Valley, northwest Syria: a palynological study Reviewed

Y. Yasuda, H. Kitagawa and T. Nakagawa

Quaternary International Vol. 123/125 page： 127-136 2004

Radiocarbon contents in tree rings during the Sporer Minimum Reviewed

H. Miyahara, K. Masuda, Y. Muraki, T. Uemura, M. Kato, H. Toyoizumi, H. Furuzawa, T. Nakamura, H. Kitagawa and E. Matsumoto

Nucl. Instr. and Meth. in Phys. Res. B Vol. 233/224 page： 655-659 2004

High-resolution 14C analyses of annually-banded coral skeletons from Ishigaki Island, Japan: Implications for oceanography Reviewed

T. Mitsuguchi, H. Kitagawa, E. Matsumoto, Y. Shibata, M. Yoneda, T. Kobayashi, T. Uchida and N. Ahagon

Nucl. Instr. and Meth. in Phys. Res. B Vol. 223/224 page： 455-459 2004

Marin reservoir age in the south of Vietnam estimated from an annually-banded coral skeleton Reviewed

Dang X. Phong, T. Mitsuguchi, H. Kitagawa, Y. Shibata and T. Kobayashi

Radiocarbon Vol. 46 ( 2 ) page： 657-660 2004

Environmental archaeology at the Chengtoushan site, Hunan Province, China, and implications for environmental change and the rise and fall of the Yangtze River civilization Reviewed

Y. Yasuda, T. Fujiki, H. Nasu, M. Kato, Y. Morita, Y. Mori, M. Kanehara, S. Toyama, A. Yanoa, M. Okuno, H.

Quaternary International Vol. 123/125 page： 149-158 2004

Late-Holocene natural and anthropogenic vegetation changes in the Dongbei Pingyuan (Manchurian Plain), northeastern China Reviewed

M. Makohonienkoa, H. Kitagawa, T. Naruse, H. Nasu, A. Momohara, M. Okuno, T. Fujiki, X. Liug, Y. Yasuda and H. Ying

Quaternary International Vol. 123/125 page： 71-88 2004

Variation of the radiocarbon content of tree rings during the Spoerer Minimum Reviewed

H. Miyahara, K. Masuda, H. Furuzawa, Y. Muraki, T. Nakamura, H. Kitagawa and K. Arslanov:

Radiocarbon Vol. 46 ( 2 ) page： 965-968 2004

Late Holocene vegetation and environment at Cauduntou, west of Yangtze Delta, SW Jiangsu Province, East China Reviewed

M. Okuda, Y. Sato, L. H. Tang, M. Takahashi, S. Toyama, A. Yano, H. Kitagawa and Y. Yasuda

Quaternary International Vol. 123/125 page： 39-47 2004

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Papers - KITAGAWA, Hiroyuki