湖北郧县辽瓦店黄土剖面风化特征及其对气候变化的响应
收稿日期: 2014-08-19
修回日期: 2014-10-09
网络出版日期: 2015-05-20
基金资助
国家自然科学基金项目(41271108,41371029);国家社会科学基金项目(14BZS070);中央高校基本科研业务费项目(GK201301003)
Pedogenic Characteristics of Liaowadian Holocene Loess Profile in the Upper Hanjiang River Valley of China and Its Response to Climate Change
Received date: 2014-08-19
Revised date: 2014-10-09
Online published: 2015-05-20
对湖北郧县辽瓦店剖面的沉积学特征及磁化率、粒度、Rb、Sr含量等理化指标进行了研究。结果表明:辽瓦店剖面自下而上具有马兰黄土(L1)-过渡层(Lt)-古土壤(S0)-全新世黄土(L0)-表土(TS)地层序列;不同地层单元的风化成壤差异明显,其成壤强弱顺序为古土壤S0成壤最强、全新世黄土L0和过渡层Lt次之、马兰黄土L1最弱。成壤强弱的变化揭示出该区晚更新世末期(11 500 a BP以前)气候干冷,全新世早期(11 500~8 500 a BP)气候处于晚更新世干冷向全新世中期暖湿的过渡阶段,全新世中期(8 500~3 100 a BP)气候最为温暖湿润,全新世晚期(3 100 a BP以来)气候转为干冷且逐渐恶化的变化过程。
崔天宇 , 庞奖励 , 黄春长 , 查小春 , 周亚利 , 吴帅虎 , 杨建超 . 湖北郧县辽瓦店黄土剖面风化特征及其对气候变化的响应[J]. 中国沙漠, 2015 , 35(3) : 610 -615 . DOI: 10.7522/j.issn.1000-694X.2014.00150
The Liaowadian (LWD) profile in Yunxian, Hubei of China was surveyed in details. Investigations into this soil profile, including pedo-stratigraphy, chronology, were carried over the first river terrace of the upper Hanjiang River valley. Magnetic susceptibility, particle-size distribution, the contents of Rb and Sr were analyzed in laboratory. The result shows that LWD profile recorded the environment features and evolution with the stratigraphic series TS-L0-S0-Lt-L1. Different degree of weathering intensity in different stratigraphic units is paleosol S0 > Holocene loess L0 > modern TS>transitional loess layer Lt > Malan loess layer L1. The climate was dry and cold before 11 500 a BP and dust falls led to the formation of Malan loess layer L1. And between 11 500 a BP and 8 500 a BP, the climate got warmer, and was characterized by dry and wet, and dust falls led to the formation of Transitional loess layer Lt. During 8 500 a BP to 3 100 a BP, Yunxian basin experienced its warmest period with a warm and humid climate during Holocene, and dust falls led to the formation of S0. During the late Holocene, namely 3 100 a BP, the climate was deteriorating very quickly. It turned from warm to cold, and precipitation began to decline.
Key words: loess-paleosol sequence; weathering degree; climate change; Liaowadian
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