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关中地区不同耕作历史土壤的微形态特征及对比研究

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土壤通报 2009年第3期40卷 476-481页

作者：庞奖励张卫青黄春长张旭查小春陕西师范大学旅游与环境学院陕西西安710062 中国科学院地球环境研究所黄土与第四纪地质国家重点实验室陕西西安710075

用显微镜和Qwin软件对关中地区不同耕作历史土壤A和B的微形态进行了观察和定量分析.结果表明:耕作土壤具有Ap-(BC)-C构造;不同土壤粗颗粒主要由石英和长石组成,但不同矿物间的比例、颗粒形态、C/F(10μm)值等有明显差异.耕作历史和方式... 详细信息

用显微镜和Qwin软件对关中地区不同耕作历史土壤A和B的微形态进行了观察和定量分析.结果表明:耕作土壤具有Ap-(BC)-C构造;不同土壤粗颗粒主要由石英和长石组成,但不同矿物间的比例、颗粒形态、C/F(10μm)值等有明显差异.耕作历史和方式对矿物组合影响不明显,但对颗粒形态有显著的影响,耕作时间愈长,颗粒的长度、等圆直径、周长和面积减小和圆度增加愈明显。

关键词：土壤微形态耕作历史关中地区

A major reorganization of Asian climate by the early Miocene

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A major reorganization of Asian climate by the early Miocene

中国科学院地质与地球物理研究所2.08学术年会

作者： Z.T.Guo~1,B.Sun~(1,2.,Z.S.Zhang~(1,3),S.Z.Peng~1,G.Q.xiao~4,J.Y.Ge~4,Q.Z.Hao~1,Y.S.Qiao~1,M.Y.Liang~1, J.F.Liu~1,Q.Z.Yin~1,and J.J.Wei~1 1 key {2. of Cenozoic geology and {2.,institute of geology and Geophysics,chinese academy of sciences,P.O.Box 982.,Beijing,10002.,China 2.Shandong institute and {2. of Geological sciences,Jinan,2.0013,China 3 Nansen-Zhu International Research Center,institute of Atmospheric Physics,chinese academy of sciences,Beijing, 10002.,China 4 state key laboratory of loess and quaternary geology,institute of earth {2.,chinese academy of sciences,P.O. Box 17,xian,{2.},China

The global climate system experienced a series of drastic changes during the *** Asia,these include the climate transformation from a zonal pattern to a monsoon-dominated pattern,the disappearance of typical subtropical aridity,and the onset of inland *** major advances in the last two decades in characterizing and understanding these climate phenomena,disagreements persist relative to the timing,behaviors and underlying causes. This paper addresses these issues mainly based on two lines of ***,we compiled newly collected data from geological indicators of the Cenozoic environment in China as paleoenvironmental maps of ten *** confirming the earlier observation that a zonal climate pattern was transformed into a monsoonal one,the maps within the Miocene indicate that this change was achieved by the early Miocene,roughly consistent with the onset of {2. deposition in *** a monsoon-like regime would have existed in the Eocene,it was restricted to tropical-subtropical *** latitudinal oscillations of the climate zones during the Paleogene are likely attributable to the imbalance in evolution of polar ice-sheets between the two hemispheres. Secondly,we examine the relevant depositional and soil forming processes of the Miocene {2.-soil sequences to determine the circulation characteristics with emphasis on the early *** eolian deposition in the middle reaches of the Yellow River since the early Miocene firmly indicates the formation of inland deserts,which have been constantly maintained during the past 2. ***- size gradients between {2. sections indicate northerly dust-carrying winds from northern sources,a clear indication of an Asian winter monsoon ***,welldeveloped Luvisols show evidence that moisture from the oceans reached northern *** evidence shows the coexistence of two kinds of circulations,one from the ocean carrying moisture and another from the inland des

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西安黄绵土碳释放规律研究

土壤 2004年第4期36卷 398-404,411页

作者：张晓龙赵景波马润花中国海洋大学环境科学与工程学院山东青岛266003 陕西师范大学旅游与环境学院山东烟台师范学院地理系山东烟台264025

采用碱溶液吸收法。1999 年 9 月～2.01 年 8 月 2.年的观测资料显示,西安黄绵土 CO2.放与前人在其他地区的研究不同,表现为白昼释放量低于夜间。西安土壤 CO2.放量的日变化从当日清晨至次日晨,呈现由高变低再变高的变化规律。土壤 CO... 详细信息

采用碱溶液吸收法。1999 年 9 月～2.01 年 8 月 2.年的观测资料显示,西安黄绵土 CO2.放与前人在其他地区的研究不同,表现为白昼释放量低于夜间。西安土壤 CO2.放量的日变化从当日清晨至次日晨,呈现由高变低再变高的变化规律。土壤 CO2.放量的变化趋势大体与温度的变化一致,但在时间上有一定的滞后性。随着季节的变化,西安黄绵土 CO2.放量有明显的增减,夏季日释放量最多,秋季次之,冬季最少。不同植被条件下,土壤 CO2.释放量有差异。一般说来,裸地有较高的释放量,林地和草地释放量较低。裸露地表土壤 CO2.释放量变化较大,地表覆盖良好,CO2.放较为稳定。

关键词：黄绵土土壤CO2 释放量变化规律西安

CSCO_3 CYCLES IN SALAWUSU RIVER BASINSINCE 150KA B.P.

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chinese Geographical Science 2001年第4期11卷 50-56页

作者： LUO Kai-li1,2. LI Bao-sheng1,2. ZHU Yi-zhi2. JIN He-ling3, ZHANG David Dian4, YAN Man-cun5, LI Hou-xin1, YAO Chun-xia1, ZHANG Yu-hong1f 1. Department of Geography, South China Normal University, Guangzhou 510631, P. R. China 2. {2. key Labor

ABSTRACT: This paper, with Milanggouwan stratigraphic section as a typical section of the Salawusu River Basin, explores the relation between CaCO3 content distribution and climate change since 150 ka B. P. and concludes that: 1) The low-high changes of CaCO3 content in the section has a remarkable corresponding relation with the sedimentary cycles of ancient aeolian sand and overlying fluviolacustrine facies or palaeosols. 2. CaCO3 distribution in aeolian sand is relatively meagre, ranging from 0. 8% - 7. 18%, or on an average 2. 50% but relatively enriches in the fluviolacustrine faceis and palaeosols, ranging from 2. 2.% - 14. 9% , or on an average 5. 74%. This implies that they have different climatic backgrounds. The former was the product of erosion, transport and deposition by wind under arid and cold climatic conditions, whereas the latter was related to its special low-lying geomorphic position between the Ordos Plateau and loess Plateau and warm-humid climatic environment. When the climatic became warm and humid, fluviolacustrine and swamp facies developed, soil-forming action strengthened, and low-lying catchment condition was favorable to CaCO3 accumulation. 3) The basic cause responsible for the multicycle of CaCO3 migration and accumulation in the Milanggouwan section may be the multiple alterations of winter and summer monsoons over the Mu Us Desert under the influences of climatic fluctuation of glacial and interglacial periods in the Northern Hemisphere since 150ka B. P. .

关键词： Milanggouwan section 150ka B. P. CaCO3, 2. sediment-climatic cycles

A study on responses of soil erosion and sediment yield to closing cultivation on sloping land in a small catchment using 137Cs technique in the Rolling loess Plateau,China

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A study on responses of soil erosion and sediment yield to c...

Carbon isotopic composition of alkenes in paleosol with PY-GC-IRMS: Implications for paleovegetation changes on the loess Plateau, China

中国科学院地质与地球物理研究所2.03学术年会

作者： FENG Mingyi~(1,4),D.E.Walling~3,ZHANG xinbao~(1,2. & WEN Anbang~1 1.Chengdu institute of Mountain Hazards and {2.,{2. academy of sciences(CAS).Chengdu 610041.China 2.state key laboratory of loess and quaternary geology.institute of earth {2.,CAS,xi’an 710075.China 3.Department of Geography and Archaeology.Exeter University,Exeter EX4 4RJ.UK 4.Sichuan Teachers College.Nanchong 637002.China

By comparison of volumes and Cs contents of the deposited sediments before and after 1993,changes of specific sediment yields and relative sediment contributions from the gully area and from the inter gully area after closing cultivation on the later area on a small catchment of Zhaojia Gully,in the Rolling loess Plateau,are analyzed in this *** cultivation in a large scale has not resulted in decrease but increase of specific sediment yield of the catchment,in sharp decrease of the sediment yield and the relative sediment contribution of the inter-gully area, and in increase of the sediment yield and the contribution of the gully area,for a short *** mean specific sediment yield of 2.650 t km a of 1994-1996 in the catchment was 2.2.times the average value of 13413 t km a for a long *** specific sediment yield of the inter-gully area decreased from the 14335 t km a in 1994 to 7034 t km a in 1995 and 3517 t km a in 1996,while the yield of the gully area varied between 44944 and 62.36t km a during the period of 1994-1996 which was much greater than the value of 2.118 t km a before *** relative sediment contribution from the inter-gully area decreased from 2.% in 1994 to 15%in 1995 and 6%in 1996,while the contribution from the gully area increased from 77%in 1994 to 85% in 1995 and 94%in *** is suggested that compacting of ploughed soils resulted in increasing of the erosion resistance but in decreasing of the precipitation infiltration,therefore, the soil erosion reduced but the runoff amount increased on the inter-gully *** of delivering runoff from the inter-gully area to the gully area should result in activeness of gully erosion and mass movements,consequently,in increase of the total sediment yield from the catchment.

关键词： loess Plateau closing cultivation gully ara inter-gully area relative sediment contribution 137Cs

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chinese Journal Of Geochemistry 2006年第B08期25卷 281-281页

作者： Weiguo LIU, Yongsong HUANG state key Lab. of {2. and {2. geology, institute of earth and environment, chinese academy of sciences, xi’an710075, China Department of Geological sciences, Brown University, Providence, RI 02.06, USA 1. state key Lab. of {2. and {2. geology Institute of Earth and Environment Chinese Academy of Sciences 710075 Xi’an China 2. Department of Geological sciences Brown University 02906 Providence RI USA

Effect of regional land subsidence on engineering structures:a case study of the 6 km long Su-tong Yantze River Bridge

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Effect of regional land subsidence on engineering structures...

菏泽市冬季PM_(2.5)中二元羧酸类SOA的昼夜变化特征

中国科学院地质与地球物理研究所第11届（2.11年度）学术年会

作者： F.S.Ma·Y.S.Yang·R.M.Yuan·B.K.Yao J.Guo key laboratory of Engineering Geomechanics,{2. of {2. and Geophysics,chinese academy of sciences, Beijing 10002.,People’s Republic of China College of environment and Resources,Jilin University, Changchun 13002.,People’s Republic of China School of earth Ocean and Planetary sciences, Cardiff University,Cardiff CF10 3YE,UK National Center for Active Fault studies,{2. of {2., China earthquake Administration,Beijing 10002., People’s Republic of China {2. of Geological Survey of Jiangsu Province, Nanjing 2.0018,People’s Republic of China

The article reports a study of the influence of regional land subsidence on the 6.05 km long Su-tong Yangtze River *** characteristics of the major compressive geological layers and their potential to settlement are discussed in the light of the past and continuing groundwater exploitation in the area.A numerical model for land subsidence quantification was developed and used to predict the differential settlements along the bridge axis to *** is a significant difference in the settlement occurring in the north and south areas of the bridge,in part due to the variation in the quaternary alluvial sediments. The case study highlights the importance of considering both site specific and regional subsidence conditions when designing large structures in such an area.

关键词： Land subsidence environmental risk Overexploitation Highway bridge Su-xi-Chang area

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环境科学 2018年第11期39卷 4876-4884页

作者：孟静静刘晓迪侯战方李静魏本杰邢继钊聊城大学环境与规划学院聊城252000 中国科学院地球环境研究所黄土与第四纪地质国家重点实验室西安710061

为研究菏泽市冬季大气气溶胶中二元羧酸类化合物的昼夜变化特征与形成机制,于2.17年冬季(12.)进行为期1个月的PM_(2.5)样品采集,并分析二元羧酸、酮羧酸、α-二羰基化合物及左旋葡聚糖等化学组分.结果表明,菏泽市冬季PM_(2.5)中白天二... 详细信息

为研究菏泽市冬季大气气溶胶中二元羧酸类化合物的昼夜变化特征与形成机制,于2.17年冬季(12.)进行为期1个月的PM_(2.5)样品采集,并分析二元羧酸、酮羧酸、α-二羰基化合物及左旋葡聚糖等化学组分.结果表明,菏泽市冬季PM_(2.5)中白天二元羧酸与酮羧酸的总浓度均呈昼高夜低的变化特征,但α-二羰基化合物(二元羧酸的重要前体物)的变化特征却与之相反,表明白天气溶胶的氧化程度比夜晚强.无论在白天还是晚上,草酸(C_2.均是浓度最高的二元羧酸,其次是邻苯二甲酸(Ph)、丁二酸(C_4)和丙二酸(C_3),与其他城市地区的分子组成是相似的.由C_3/C_4的比值与温度(T)间的相关性分析可知,菏泽市冬季有机化合物主要受本地源的影响,而受远源输入的影响很小. C_2.SO_4^(2.)、气溶胶实际酸度(pHIS)的相关性分析表明,C_2.要是在液相中经酸催化的二次氧化反应形成的.因为主要的二元羧酸类化合物(C_2.Gly和mGly)与左旋葡聚糖(Levo)的相关性很强,且K^+/OC的平均比值为0. 06(范围为0. 03～0. 13),所以可以得出二元羧酸类化合物及K^+主要受生物质燃烧的影响.

关键词：二元羧酸昼夜变化特征液相形成机制 PM2.5 菏泽市

Nitrogen Isotopic Fractionation Related to Nitrification Capacity in Agricultural Soils

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Pedosphere 2014年第2期24卷 186-195页

作者： SONG Ge ZHAO Xu WANG Shen-Qiang xiNG Guang-xi state key {2. of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of Sciences University of chinese academy of sciences Changshu National Agro-Ecosystem Observation and Research Station Institute of Soil ScienceChinese Academy of Sciences

A laboratory-based aerobic incubation was conducted to investigate nitrogen （N） isotopic fractionation related to nitrification in five agricultural soils after application of ammonium sulfate （（NH4）2.04）. The soil samples were collected from a subtropical barren land soil derived from granite （RGB）, three subtropical upland soils derived from granite （RQU）, quaternary red {2. （RGU）, quaternary xiashu loess （YQU） and a temperate upland soil generated from alluvial deposit （FAU）. The five soils varied in nitrification potential, being in the order of FAU 〉 YQU 〉 RGU 〉 RQU 〉 RGB. Significant N isotopic fractionation accompanied nitrification of NH4＋. 615N values of NH4＋ increased with enhanced nitrification over time in the four upland soils with NH4＋ addition, while those of NO3 decreased consistently to the minimum and thereafter increased. 515N values of NH4＋ showed a significantly negative linear relationship with NH4＋-N concentration, but a positive linear relationship with NO3-N concentration. The apparent isotopic fractionation factor calculated based on the loss of NH4＋ was 1.036 for RQU, 1.02. for RGU, 1.016 for YQU, and 1.02. for FAU, respectively. Zero- and first-order reaction kinetics seemed to have their limitations in describing the nitrification process affected by NH4＋ input in the studied soils. In contrast, N kinetic isotope fractionation was closely related to the nitrifying activity, and might serve as an alternative tool for estimating the nitrification capacity of agricultural soils.

关键词： NH+4 addition nitrification nitrogen isotope fractionation reaction kinetics