检索结果-南通市图书馆

A "Yellow Cap" on quaternary red clay in Jiujiang,Jiangxi Province

Pedosphere 1999年第4期9卷 311-318页

作者： HU XUEFENG GONG ZITONG(1State Key Laboratory of Loess and quaternary Geology, the Chinese Academy of Sciences, P. O. Box: 17,xi’an 710054 (China))(2Institute of Soil Science, the Chinese Acodemy of Sciences, P. O. Box 821, Nanjing 210008 (China)) 中科院地球环境所黄土与第四纪地质国家重点实验室陕西西安 710054 中科院南京土壤所江苏南京 210008

A thin layer of yellow-brown-colored earth was generally found on quaternary red clay in Jiujiang,Jiangxi Province. A typical profile was established. Both particle size distribution and REE (rare earthelements) characteristics of the yellow-brown-colored earth of the profile fully suggested its aeolian origin andclose similarity to Naming Xiashu loess. The study also implied aeolian origin of the underlying quaternaryred clap Compared with the red clay, the yellow- brown- colored earth was less weathered because of its lowercontent of free iron and higher mole ratios of SiO2/A12O3 and SiO2/(Fe2O3+A12O3 ) as well as its lessdeveloped chemical microtextures of quartz *** order to study the aged of the two deposits comparatively, the thermoluminescent dating method wasused. As a result, the bottom of the yellow-brown-colored esrth was dated to 6015 ka B. P. and the upperpart of the red clay 38854 ka B. P. It was suggested that the yellow- browm- colored earth was formed inthe Late Pleistocene and was probably the aeolian deposit of the Last Glacial, which corresponded with theMalan loess in the Loess Plateau of the northwestern part of China; while the underlying red clay was formedin the Middle Pleistocene.A "yellow cap" on quaternary red clay in Jiujiang implied a great climatic and environmental varistionin the beginning of the Late Pleistocene in the southern pot of China, especially in the middle and lowerreaches of the Yangtze River. The eveal not only halted the rubification, once dominating the region, butalso produced a widespread covering of aeolian deposit, as only occurred in the cold and dry environment.

关键词： aeolian deposits quaternary red clay rubification yellow-brown-colored earth

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Origin of quaternary red clay of Southern Anhui Province

引用

Pedosphere 1998年第3期8卷 267-272页

作者： HUXUEFENG YUANGUODONG 等 InstituteofSoilScience theChineseAcademyofSciences.P.O.Box821Nanjing210008（China） InstituteofSoilSci

The particle size distribution, heavy mineral constituents and rare earth elements (REE) characteristics of the quaternary red clay of southern Anhui Province were studied to explore the origin of the clay. The results showed that the clay had some properties of areolian deposits, which could be compared with those of the loess in North China; and its chondrite normalized curves of REE were similar to those of the Xiashu loess, implying that they shared the same origin. It was concluded in combination with the results reported by other researchers that the quaternary red clay of southern Anhui Province originated from aeolian deposits, and this could reveal the cycles of warm and cold climates in the area during the quaternary period.

关键词： heavy mineral constituents particle size distribution quaternary red clay rare earth elements characteristics

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Characteristics of runoff and sediment yield for two typical erodible soils in southern China

引用

International Journal of Sediment Research 2022年第5期37卷 653-661页

作者： Xuchao Zhu Yin Liang Lili Qu Longxi Cao Zhiyuan Tian Tong Liu Meng Li State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences College of Advanced Agricultural Sciences University of Chinese Academy of Sciences College of Ecology and Environment Chengdu University of Technology National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China Guangdong Key Laboratory of IntegratedAgro-environmental Pollution Control and Management Institute of Eco-environmental and Soil Sciences Guangdong Academy of Sciences Hydrology and Water Resources Investigation Bureau of Jiangsu Province

Granite red soil(GRS) and quaternary red clay(QRC) are two typical erodible soils in the red-soil region of southern China. Analytical and comparative studies of the characteristics of runoff and sediment yield for the two soils at various slopes are currently needed. The purpose of the current study was to clarify the characteristics of runoff and sediment yield for GRS and QRC at different slopes and to establish models for estimating sediment yield for the two soils. Forty-eight runoff microplots with four slopes(5°, 15°, 25°, and 35°) and two soils(GRS and QRC) were established and exposed to natural rainfall. Runoff and sediment yield were measured 10 times during the study period. Runoff and sediment yield for the two soils under the various slopes had similar temporal variations, and both increased with prior cumulative erosive rainfall. Runoff for GRS and QRC was moderately temporally variable, with coefficients of variation(CVs) from 46.2% to 60.6%, and sediment yield for QRC was strongly temporally variable, with CVs from 114.8% to 145.8%. Sediment yield for GRS increased with slope, but sediment yield for QRC first increased and then decreased, with a calculated inflection point of 18°, but runoff for both soils decreased with slope. The CVs of both runoff and sediment yield with slope for the two soils ranged from 3.6% to 88.0%, lower than the temporal variabilities, indicating that rainfall may have a larger impact than slope on runoff and sediment yield for QRC and GRS. Under the various slopes, runoff and sediment yield for both soils increased with rainfall and sediment yield increased with runoff, but the proportions of effective rainfall and runoff differed. Pedotransfer-function models based on rainfall, runoff, and slope accurately estimated sediment yield for the two soils, with the model fit coefficient of determination(R2) > 0.81 and the R2for verification >0.79. These results improve the understanding of the laws governing erosion for differe

关键词： Runoff and sediment characteristics Sediment-yield simulation Granite red soil quaternary red clay Pedotransfer function red-soil region

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：