Yellow-brown earth on Quaternary red clay in Langxi County, Anhui Province in subtropical China: Evidence for paleoclimatic change in late Quaternary period†
Yellow-brown earth on Quaternary red clay in Langxi County, Anhui Province in subtropical China: Evidence for paleoclimatic change in late Quaternary period†
复制标题
DOI：
10.1002/jpln.200700017
复制
发表时间：
2008-08
影响因子：
2.5
通讯作者：
Xuefeng Hu;Wenlong Jiang;W. Ye;Ming-Neng Shen;Weiguo Zhang;Hong-bo Wang;Cheng Lu;Lidong Zhu
中科院分区：
文献类型：
--
作者：
Xuefeng Hu;Wenlong Jiang;W. Ye;Ming-Neng Shen;Weiguo Zhang;Hong-bo Wang;Cheng Lu;Lidong Zhu
为探讨华南地区晚第四纪古气候变化及其对成壤作用和土壤分类的影响，对安徽郎溪县黄棕壤-红粘土剖面进行了研究。剖面的粒度分布、常量元素和微量元素组成表明，该剖面的黄土与九江、宣城的黄土和镇江的下蜀黄土同源，下伏RC也具有风成特征，与下蜀黄土同源。研究了不同粒度的SiO2/Al 2 O3、SiO（Al 2 O3 +Fe 2 O3）和BA（[CaO+MgO+ K2 O+Na 2 O]/Al 2 O3）等风化指标（CaO/TiO 2，MgO/TiO 2，K2 O/TiO 2，Na 2 O/TiO 2，Rb/Sr）的变化表明，RC的风化作用比YBE强。该剖面均匀红粘土的磁化率明显增强。而下伏网纹红粘土（RRC）由于古地下水的运动，其强度明显降低，不能反映其强风化性。郎溪县YBE-RC剖面记录了第四纪晚期气候的巨大变化：RC的成土作用结束，出现了广泛的沙尘沉降。RC的母质可能是末次间冰期前堆积的风成沉积物，并在随后的间冰期气候下被强烈风化和红化。结果表明，研究区红壤和黄棕壤共存，这与土壤地带性分布理论相矛盾。因此，在研究成壤作用时，有必要考虑第四纪气候变化的历史。
In order to investigate the paleoclimatic changes in S China during the late Quaternary and their influence on pedogenesis and soil classification, a yellow-brown earth (YBE)-red clay (RC) profile in Langxi County, Anhui Province was studied. The grain-size distribution and the major- and trace-element compositions of the profile indicate that the YBE of the profile shares the same origin with the YBE in Jiujiang and Xuancheng and the Xiashu loess in Zhenjiang, and the underlying RC also has aeolian characteristics and shares the same origin with the Xiashu loess. Grain-size characteristics, molecular ratios of SiO 2 /Al 2 O 3 , SiO 2 /(Al 2 O 3 +Fe 2 O 3 ), and BA ([CaO+MgO+K 2 O+Na 2 O]/Al 2 O 3 ) and other weathering indices (CaO/TiO 2 , MgO/TiO 2 , K 2 O/TiO 2 , Na 2 O/TiO 2 , and Rb/Sr) of the profile indicate that the RC is more strongly weathered than the YBE. Magnetic susceptibility (Χ lf ) of the uniform red clay (URC) of the profile is significantly enhanced. However, that of the underlying reticulate red clay (RRC) is significantly decreased because of the paleogroundwater movement and cannot indicate its strong weathering properties. The YBE-RC profile in Langxi County recorded a great climatic change during late Quaternary: At that time, the pedogenic development of the RC was terminated and widespread dust deposition occurred. The parent material of the RC may be aeolian deposits which were accumulated before the last interglacial and were strongly weathered and rubified under the subsequent interglacial climate. It is observed that red soils, derived from the RC, and yellow-brown soils, derived from the YBE, coexist in the study area, which is contradictive to the theory of the zonal distribution of soils. Therefore, it is necessary to take into account the history of Quaternary climatic changes when studying pedogenesis.