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亚热带更新世沉积物发育土壤的特性和定量分类研究 被引量:1
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作者 章明奎 王人潮 《浙江大学学报(农业与生命科学版)》 CAS CSCD 1993年第S1期115-125,共11页
在野外调查的基础上,从土壤实体的属性出发,对分布于我国亚热带地区长江中下游丘陵阶地上、沉积年龄差距达几十万年、呈交叉分布的三类古老厚层运积母质——下蜀黄土、Q_2、Q_3红土上发育的23个代表性土壤剖面,作了较系统的室内分析和... 在野外调查的基础上,从土壤实体的属性出发,对分布于我国亚热带地区长江中下游丘陵阶地上、沉积年龄差距达几十万年、呈交叉分布的三类古老厚层运积母质——下蜀黄土、Q_2、Q_3红土上发育的23个代表性土壤剖面,作了较系统的室内分析和定量分类研究,目的是阐明这些土壤的发生学特性,明确它们的分类地位。通过对土壤颜色、颗粒组成、土壤酸度、电荷特性、土壤风化淋溶系数、粘粒和粉砂的硅铝率、铁形态组成、自然粘粒率、硅反应指标和硅饱和度指标等的分析。结果表明,这些中晚更新世沉积物发育的土壤的属性虽受现代成土条件的作用已产生了一定的变化,但在其形成的土壤中仍有明显残留的特点,母质对土壤性质有较大的影响。用数值分类和诊断分类等定量方法,可把本研究土壤分为四类。诊断分类与数值分类有74%的分类结果相同,但诊断分类还有一些不足之处。作者认为根据土壤属性进行数值分类是土壤分类的发展方向。 展开更多
关键词 亚热带 更新世沉积物 土壤属性 诊断分类 数值分类
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安徽宣城中晚更新世沉积物与北方黄土的对比研究
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作者 房迎三 《湖南考古辑刊》 1999年第1期160-164+251,共5页
对比了宣城更新世中晚期沉积物与北方黄土在粒度成分、化学成分、重矿物组成等方面的异同,提出宣城土状堆积的主要物质来源可能与北方地区的黄土同源。
关键词 对比研究 更新世沉积物 安徽宣城 北方黄土
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Multi-proxy evidence for Late Pleistocene-Holocene climatic and environmental changes in Lop-Nur,Xinjiang,Northwest China 被引量:3
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作者 LUO Chao YANG Dong +4 位作者 PENG Zicheng ZHANG Zhaofeng LIU Weiguo HE Jianfeng ZHOU Chenlin 《Chinese Journal Of Geochemistry》 EI CAS 2008年第3期257-264,共8页
A 10.35-m-long sediment core from the Luobei depression in Lop-Nur,Xinjiang,Northwest China,provides detailed information about environmental changes during the Late Pleistocene.The samples taken every 5 cm of the cor... A 10.35-m-long sediment core from the Luobei depression in Lop-Nur,Xinjiang,Northwest China,provides detailed information about environmental changes during the Late Pleistocene.The samples taken every 5 cm of the core were analyzed for 10 environmental proxies,including magnetic susceptibility,granularity,chroma,carbonate and loss on ignition(LOI),and pH value.The chronology data are provided by the uranium/thorium disequi-librium dates.The sediments of the section were deposited during the last 32000 years.The results of analysis of 10 proxies were examined using multivariate statistical analysis,and the principal components were calculated.According to the results,the Late Pleistocene sequence contains four climatic and environmental stages appearing in the cycles of cold-wet and warm-dry changes.During 10-9 ka BP,it was the earliest warm episode in the Holocene.Environmental changes in this district were restricted by global change,as suggested by the analysis of glacial-interglacial cycles.But it was different from the mutative trend of a monsoon region in East China because of its own characteristics,which was the situation of cold-wet and warm-dry climate-environment change.The candidate reason may be the uplift of the Tibet Plateau and the westerly wind circulation. 展开更多
关键词 更新世沉积物 气候变化 环境代理 新疆
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Aepyosciurinae——a new subfamily of Sciuridae(Rodentia,Mammalia)from basal loess deposits at the northeastern border of Tibetan Plateau 被引量:4
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作者 WANG Banyue & QIU Zhanxiang Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China 《Chinese Science Bulletin》 SCIE EI CAS 2003年第7期691-695,共5页
Aepyosciurinae, a new subfamily of Sciuridae, were found at the base of the early Pleistocene loess deposits in Dongxiang County, Gansu Province. Its unilaterally hyp-sodont and lophodont cheek teeth are unique among ... Aepyosciurinae, a new subfamily of Sciuridae, were found at the base of the early Pleistocene loess deposits in Dongxiang County, Gansu Province. Its unilaterally hyp-sodont and lophodont cheek teeth are unique among the sciurids so far known all over the world. Certain degree of similarity can be observed between the cheek teeth of the new subfamily and the Anomalurinae living in tropical and subtropical forests in central and western Africa. Aepyosci-uris orientalis gen. et sp. nov. might have lived in montaneous woodland or grassland and lived on harder leaves, barks, or even grass. This tends to show that the northeastern border area of the Tibetan Plateau had been lifted considerably high in early Pleistocene (ca. 2 Ma), with drier climate, becoming a suitable habitat for Aepyosciurus orientalis. 展开更多
关键词 西藏高原 松鼠 亚科 啮齿目 哺乳纲 更新世黄土沉积物 古动物分类学
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