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Pollen transport in the Shiyang Rive

時間:2023-04-27 05:05:29 環(huán)境保護(hù)論文 我要投稿
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Pollen transport in the Shiyang River drainage, arid China

In order to assess the contribution of the pollen transported by wind and fluvial flows to the pollen spectra in Shiyang River drainage, a typical small endorheic drainage in arid lands of northwest China, preliminary studies on modern pollen rain along two transects with 91 surface soil samples, 8 atmospheric samples, 30 modern fluvial flow samples and 50 riverbed mud samples, were carried out. Results show that dispersal agents (air, flowing water) have dissimilareffects on transport of pollen and the structure of pollen spectra. Fluvial flow has a stronger capacity than wind to transport large quantities of pollen overlong distances. Pollen transported by fluvial flow makes a large contribution to the pollen spectra of riverbed alluvial sediments. Paleoenvironmental reconstructions undertaken using pollen spectra from fluvial sediments in arid lands arestrongly influenced by pollen transport. Therefore, the sources, the transportation agents and the depositional condition of pollen should be systematically investigated before pollen assemblages are used to derive the environmental significance in such settings.

作 者: ZHU Yan XIE Yaowen CHENG Bo CHEN Fahu ZHANG Jiawu   作者單位: ZHU Yan(Center for Arid Environment and Paleoclimate Research, National Laboratory of West China's Environmental System, Lanzhou University, Lanzhou 730000, China;College of Geography and Environment, Northwest Normal University, Lanzhou 730070, China)

XIE Yaowen,CHENG Bo,ZHANG Jiawu(Center for Arid Environment and Paleoclimate Research, National Laboratory of West China's Environmental System, Lanzhou University, Lanzhou 730000, China)

CHEN Fahu(Center for Arid Environment and Paleoclimate Research, National Laboratory of West China's Environmental System, Lanzhou University, Lanzhou 730000, China;Key Laboratory of Desert and Desertification, Cold and Arid Regions Environme ntal and Engineering R) 

刊 名: 科學(xué)通報(英文版)  SCI 英文刊名: CHINESE SCIENCE BULLETIN  年,卷(期): 2003 48(14)  分類號: X14  關(guān)鍵詞: modern pollen transport   arid regions   Shiyang River drainage