Grant-in-Aid for Scientific Research (A)
|Allocation Type||Single-year Grants |
|Research Institution||Nagoya University (2004)|
Aichi Prefectural University (2002-2003)
NISHIDA Tamihito (2004) Nagoya University, Graduate School of Environmental Studies, Research Associate, 環境学研究科, 助手 (60313988)
半田 暢彦 (2002-2003) 愛知県立大学, 情報科学部, 教授 (00022559)
TANOUE Eiichiro Nagoya University, Graduate School of Environmental Studies, Professor, 環境学研究科, 教授 (50133129)
HARADA Naomi Japan Agency for Marine-Earth Science and Technology, Researcher, 研究員 (70344281)
UCHIDA Masao Japan Agency for Marine-Earth Science and Technology, Researcher, 研究員 (50344289)
SHIRAIWA Yoshihiro University of Tsukuba, Institute of Biological Science, Professor, 生物科学系, 教授 (40126420)
HARA Seiko Mryazaki International College, Faculty of Comparative Culture, Professor, 比較文化学部, 助教授 (50261243)
西田 民人 名古屋大学, 大学院・環境学研究科, 助手 (60313988)
|Project Period (FY)
2002 – 2004
Completed (Fiscal Year 2004)
|Budget Amount *help
¥48,230,000 (Direct Cost: ¥37,100,000、Indirect Cost: ¥11,130,000)
Fiscal Year 2004: ¥5,330,000 (Direct Cost: ¥4,100,000、Indirect Cost: ¥1,230,000)
Fiscal Year 2003: ¥20,280,000 (Direct Cost: ¥15,600,000、Indirect Cost: ¥4,680,000)
Fiscal Year 2002: ¥22,620,000 (Direct Cost: ¥17,400,000、Indirect Cost: ¥5,220,000)
|Keywords||Saline lake / Desert Area in China / Reconstruction of Paleoenvironment / Alkenone temperature / Climate Change / Lignin-Phenol / Holocene / Nitrogen isotope ratio / 中国砂漠域 / 中国西部砂漠域 / 長鎖アルケノン / 炭素・窒素安定同位体比 / 花粉分析 / ボステン湖 / ドブス湖 / 中国西部砂漠域塩湖 / 堆積物 / アイビー湖 / 14C年齢 / アルケノン水温 / 炭素窒素安定同位体比|
An aim of this work is to reconstruct the paleoenvironmental change of the present to the middle Holocene surrounding the saline lakes in the western to northeastern desert China. To achieve this aim, several proxies such as C/N ratio of sediment organic matter, long chain alkenones ratio, carbon and nitrogen stable isotope ratios and lignin-phenols were applied to the sediment samples collected from the Bosten Lake in the Xinjiang Uygrur Zizhiqu ( 41° 56.176 'N,86° 48.055 'E, Altitude 1.030 m ) and the DaBuSu Lake in Jilin (44° 45.20 'N,123° 34.30 'E, Altitude 450 m) and following results were obtained.
1)The reconstruction of the paleoenvironmental change in the Bosten Lake
(1)Alkenone temperatures ranging from 0.5 to 10.1℃ were found for the surface water of this lake after 3.5 kyrBP to the present. The temperature change was further divided to the three stages of (a)the cold climate before 3.5 kyrBP, (b)the warm climate between 2.7-1.5 kyrBP and (c)relatively cold climate after 1.5 kyrBP to the present.
(2)Carbon and nitrogen stable isotope ratios suggested that material cycles of this lake were changed to a great extent due the nitrogen fixation process and vegetation change surrounding the lake.
2)The reconstruction of the paleoenvironmental change in the DaBuSu Lake
(1)Analytical data of the lignin phenols of the sediment samples indicated that the marked change of vegetation surrounding this lake is distinctive from the Gymnosperm (present to 3 kyrBP) to the Angiosperm (3-5 kyBP). This suggests that this area has a warm climate in the middle of the Holocene.
(2)Relatively high values of the Alkenone temperature ware obtained in the sediment samples from 3-5 kyrBP. The results were basically agreed to the vegetation change of this lake area.