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1.
湖南澧阳平原玉成土壤剖面粒度组成及其环境意义   总被引：1，自引：0，他引：1  
通过对澧阳平原大量的野外考察、典型剖面玉成(YC)土壤剖面的系统采样和室内粒度分析和年代学分析,探讨了YC土壤剖面的粒度特征,揭示了澧阳平原末次冰期至全新世早期环境演变过程。研究结果表明,澧阳平原YC土壤剖面沉积物粒度无砾石,野外调查发现土壤剖面无明显层理,沉积物主要以粉砂为主,属于典型风尘沉积物特征,非水流沉积物。澧阳平原YC土壤剖面沉积物粒度经历了粗-变细-细-粗-细的变化过程,表明澧阳平原YC土壤剖面记录了末次冰期至全新世早期环境经历了5次明显变化,大致为56.0kaBP～31.8kaBP为相对寒冷干旱,31.8kaBP～23.6kaBP气候转型阶段,23.8kaBP～14.8kaBP为相对冷湿,14.8kaBP～10.6kaBP位于晚冰期阶段,气候变化剧烈,10.6kaBP～6.96kaBP为全新世早期,气候向暖湿转变。  相似文献   

2.
澧阳平原古水稻土铁形态演变特征   总被引：2，自引：0，他引：2  
刘沛  周卫军  顾海滨  李娟  郭子川  肖彦资 《土壤》2015,47(6):1151-1156
采用野外采样与室内分析的方法,研究了澧阳平原杉龙岗遗址埋藏古水稻土与现代耕作水稻土铁形态、含量变化及剖面演变特征,探讨了土壤铁形态变化与成土过程的关系。结果表明:澧阳平原现代耕作水稻土与埋藏古水稻土铁形态及含量分别为:全铁31.61~35.10 g/kg和33.97~46.88 g/kg,游离铁8.88~13.92 g/kg和11.10~20.36 g/kg,无定型铁2.52~4.06 g/kg和2.64~3.35 g/kg,结晶态铁5.06~11.40 g/kg和8.46~17.43 g/kg。澧阳平原水稻土各形态铁含量除无定型铁外,其他形态铁含量总趋势为埋藏古水稻土现代耕作水稻土,且古水稻土各形态铁分异明显。现代耕作水稻土全铁、游离铁、结晶铁含量均呈现随深度加深而增加趋势,而无定型铁则相反,且各形态铁含量波动性较小;埋藏古水稻土全铁含量随土层增深而增加,无定型铁含量呈现微幅增加趋势,但游离铁和结晶铁含量变化有异,PA剖面减少,PC剖面增加,埋藏古水稻土中各形态铁含量变化趋势多样。澧阳平原古水稻土的铁有明显的淋溶淀积特征,不同形态铁在各土层变异较大,埋藏古水稻土铁富集明显。  相似文献   

3.
对渭河流域野外实地详细调查,在渭河中游发现了具有典型古洪水滞流沉积物(SWD)的全新世黄土-古土壤沉积剖面。根据地层学对比和OSL测年,确定渭河流域在3200-2800aB.P.发生了特大古洪水事件。对沉积物地球化学特征分析表明,SWD为典型的古洪水滞流沉积物,各化学元素和氧化物的变异系数大,元素数据分布较为分散;Fe2O3、Al2O3、Ba、Cr、Cu、V、Rb含量高于S0和L0,SiO2、Zr含量低于S0和L0;化学元素粒度效应表明,SWD粒径小、粘粒强,是在滞流环境的水动力条件下沉积而成;通过气候指标Rb/Sr和Ba/Sr分析,认为古洪水滞流沉积物(SWD)记录的3200-2800aB.P.的特大古洪水事件,是在全新世大暖期结束之际,因夏季风减弱、气候系统不稳定、降水变率较大所导致的。  相似文献   

4.
通过对老官台全新世黄土剖面12种微量元素的测定分析,结合本剖面已测定的粒度、磁化率、光释光(OSL)年龄,研究和揭示了它们在表生环境下的地球化学特征和古气候意义。微量元素在风化成壤过程中,其活动性由强至弱顺序为BaSrCdPbLiZnCuCrMnCoRbNi。其中Rb、Li、Cr、Co、Zn、Cu、Mn、Ni八种元素在土壤形成过程中相对富集,含量较高;Sr、Ba、Cd三种元素在土壤中相对淋失,含量较低;但Zn、Cu、Mn、Ni、Pb五种元素对黄土层和土壤层的区别不是很明显。因此,Rb、Li、Cr、Co的高含量反映了较温湿的成壤环境,低含量反映了较冷干的粉尘加积环境;而Sr、Ba、Cd低含量反映了较温湿的成壤环境,高含量反映了较冷干的粉尘加积环境。Pb、Zn、Cu、Mn、Ni、Cd元素含量在表土层中的富集主要与现代耕作活动或工业污染有关,反映了人类活动强度的不断增强。LGT剖面主要微量元素的变化清楚地记录了关中盆地自末次冰消期以来气候环境经历的显著波动变化。  相似文献   

5.
X-荧光光谱仪、磁化率仪和激光粒度仪对尧禾村(YHC)全新世黄土-古土壤序列的微量元素、磁化率、粘粒(<5μm)含量进行了测量。将磁化率曲线、粘粒曲线、Rb/Sr变化曲线和Ba/Sr变化曲线进行了对比分析发现:YHC剖面的磁化率曲线、粘粒曲线、Rb/Sr曲线和Ba/Sr曲线具有高度的同步同向变化趋势,可很好的指示研究区域内全新世的气候变化。而元素的含量变化是该区域气候变化的结果,其中Pb元素在黄土中的含量明显高于古土壤层,属于淋失性元素。Mn、Cr、Cu、Zn、Co、Ti元素在古土壤含量高于黄土层,属于富集性元素。  相似文献   

6.
环洞庭湖区两种典型红土理化特性比较研究   总被引：1，自引：0，他引：1  
通过环洞庭湖区两种典型成因红土的野外勘察与取样、室内磁化率、粒度、微量元素(Li、Rb、Sr、Ba)分析,进行两种不同成因的红土理化性质的比较。研究结果表明,风成成因的红土粒度比基岩风化成因红土明显较细,风成成因红土以粉砂为主,基岩风化型红土为砂和粉砂为主;两种成因红土受到长江中游地区高温高湿的气候条件影响,磁化率均显示为低值,明显低于黄土高原黄土和长江下游下蜀黄土;微量元素Li/Ba、Rb/Sr比值显示为高值,显著高于黄土高原黄土和长江中下游地区下蜀黄土,表明两种红土均经历了强烈的风化淋溶过程,但基岩风化型红土的风化成壤强于风成成因红土,可能基岩风化型红土经历了更长的风化成壤过程。  相似文献   

7.
根据泾阳泾河高漫滩沉积剖面中128个样品的元素、化合物含量与粒度分析,研究了泾阳泾河高漫滩剖面沉积特征与洪水变化.结果表明,元素Ma,Ni,Cu,Zn,Ga,Pb,Ba,Rb,V和化合物Al2O3,Fe2O3,K2O含量在剖面各层中变化明显,分辨率高,能够清晰地指示洪水以及降水量的变化.JYa剖面分为18个沉积层,指示了18次大小不同的洪水和18个降水较多的年份.沉积物粒度细,元素Mn,Ni,Cu,Zn,Ga,Pb,Rb,V和化合物Al2O3Fe2O2,K2O含量高,元素Ba含量低,指示沉积时洪水强度小,洪水水位低,降雨量少.沉积物粒度粗,元素Mn,Ni,Cu,Zn,Ga,Pb,Rb,V和化合物Al2O3,Fe2O3,K2O含量低;元素Ba含量高,指示沉积时洪水强度大,洪水水位高,降雨量多.在这18次洪水事件中,在同一次洪水沉积层内形成了两个以上薄层的元素和化合物含量、粒度成分的微小变化,指示多数期次的洪水发生时期常有两个以上洪峰出现.泾阳泾河高漫滩第14,12,13,8,5,1层洪水沉积反映了泾河泾阳段全流域性的年降水量增加,且年降水量至少达到约800 mm.  相似文献   

8.
在野外考察的基础上,对泾河上游赵家村全新世黄土-古土壤剖面进行系统采样,利用X-Ray荧光光谱仪测定了Ba、Zn、Cu、Pb、Cr、Rb、Sr、Co、Th、Zr等10个微量元素的含量及其变化,并与磁化率、粒度进行了相关性分析,研究表明大部分微量元素如Ba、Zn、Cu、Rb、Co、Th、Zr在古土壤层(S0)中富集,而在马兰黄土层(L1)中含量较低; 而Pb、Cr、Sr在古土壤层中含量低于马兰黄土层.同时,微量元素Ba、Zn、Cu、Rb、Co、Th、Zr与磁化率、黏粒(<0.005 mm)含量呈正相关,与粗粉沙(0.01～0.05 mm)含量呈负相关; 而元素Pb、Cr、Sr与黏粒、磁化率呈负相关,与粗粉沙呈正相关关系.在古土壤成壤改造过程中,由于有机质含量显著增加,络合-螯合作用增大,加之黏粒胶体的吸附作用,导致大多数微量元素在古土壤层的相对富集; 而元素Cr性质稳定,在整个剖面的波动较小; Sr含量在全新世黄土层(L0)和表土层(TS)中逐渐升高,主要是由于气候暖干化日趋严重,表土层碱性增强,CaCO3淋溶作用明显减弱; Pb元素在表土层含量较高的主要原因是工业"三废"排放、金属采矿和冶炼、煤炭和石油的燃烧以及汽车尾气排放等人类活动的干扰.  相似文献   

9.
利用荧光光谱仪、等离子发射光谱,测定关中盆地卤阳湖区沉积物(0~280cm)元素含量变化,在光释光定年与R型聚类分析基础上,探讨3万年来该区26种元素的地球化学行为特征及环境意义。结果表明:卤阳湖沉积物元素大致可分4类:第1类Si、Zr、Hf、Na,指示4.6ka B.P.后湖泊萎缩,外源沉积减少;第2类Ga、U、Sr,指示4.6ka B.P.和2.0ka B.P.前后的湖区干旱气候;第3类Cu、Hg、Mn、Mg,指示4.6ka B.P.后湖水咸度的增加;第4类Ti、Sb、Pb、V、Th、Co、Fe、Bi、Cs、Zn、Ni、Rb、Ga、K、Al,这15种元素指示湖水咸度与周边人为活动的增加。元素变化特征说明,卤阳湖在33~10.4ka B.P.之间,沉积环境稳定,全新世前期(10.4~4.6ka B.P.)湖水变淡,4.6ka B.P.后,外源沉积减少,湖水咸度升高,在2.0ka B.P.前后,湖泊干旱造成大量盐分生成,之后,虽气候转湿,但人为活动增加使湖泊快速走向衰亡。  相似文献   

10.
通过对湖北省郧西县庹家湾黄土剖面的色度参数分析,并结合磁化率、粒度、铷锶比(Rb/Sr)指标揭示汉江上游地区风成黄土的色度特征及其与气候变化的关系。应用X-rite VS450型分光测色仪对庹家湾黄土剖面色度参数进行了测量。结果表明:庹家湾黄土剖面红度a*的变化与沉积物氧化铁含量呈显著正相关,平均值由高到低依次为S_0(6.34)MS(5.52)L_t(5.18)L_0(4.98)L_1(4.82)T_(1-al_2)(3.66);亮度L*的变化与氧化铁含量和有机质含量均呈负相关,其中氧化铁含量对L*的影响更大,L*在黄土层出现了峰值;色调角h*在古土壤层呈现低值(68.64°),黄土层呈现高值,a*/b*与h*特征相反,在古土壤呈现高值(0.39),黄土层呈现低值;其中在马兰黄土L_1中存在两层弱古土壤层L_1-S_2、L_1-S_1,其色度参数特征较L_1具有较高的a*值和a*/b*值及较低的L*值和h*。黄度b*指示该区域气候变化有一定的局限性,h*、a*/b*、L*和a*均可作为良好的气候替代指标,a*值和a*/b*值越大指示气候越暖湿,成壤作用越强,L*值和h*越大指示气候越冷干,成壤作用越弱。h*、a*/b*、L*和a*共同记录了该地区晚更新世以来气候经历了晚更新世末期的干冷、全新世早期逐渐回暖、全新世中期的温暖湿润、全新世晚期气候逐渐干冷,在马兰黄土形成时期,气候出现了短暂的温暖湿润期(27.5~21.5ka B.P.)。  相似文献   

11.
Trace element (TE) and rare earth element (REE) contents in red soils from the Dongting Lake area of China were determined to understanding the provenance and weathering characteristics of the red soils. The results showed similar REE distribution patterns among red soils from the Dongting Lake area, Xiashu loess from Zhenjiang, loess and the Pliocene red soil from the Loess Plateau. These patterns implied a similar provenance from dust-storms, except for red soil R5 which formed by bedrock weathering and had significant light REE (LREE) enrichment and heavy REE (HREE) depletion due to longer weathering periods and higher intensity of weathering. Trace element, especially the Rb/Sr and Li/Ba ratios, and REE, especially the LREE/HREE ratio and δEu could trace weathering intensity. Higher Rb/Sr, Li/Ba, and LREE/ HREE ratios and negative Eu anomalies were present in the red soil from the Dongting Lake area. The weathering intensity was in the decreasing order of R5 in the Dongting Lake area > red soil from the Dongting Lake area (including reticulate red soil, weak reticulate red soil, and homogeneous red soil formed by dust storms) > Xiashu loess from Zhenjiang > Loess-paleosol and Pliocene red soil from the Loess Plateau. Variations in the TE and REE contents of soil could be effectively used to study the provenance and the weathering intensity.  相似文献   

12.
Wines from three important wine-producing regions, Stellenbosch, Robertson, and Swartland, in the Western Cape Province of South Africa, were analyzed by ICP-MS and the elemental composition used in multivariate statistical analysis to classify the wines according to geographical origin. The method is based on the assumption that the provenance soil is an important contributor to the trace element composition of a wine. A total of 40 elements were determined in 40 wines. Of these, 20 elements: Li, B, Mg, Al, Si, Cl, Sc, Mn, Ni, Ga, Se, Rb, Sr, Nb, Cs, Ba, La, W, Tl, and U showed differences in their means across the three areas. In a stepwise discriminant analysis procedure, functions based on linear combinations of the log-transformed element concentrations of Al, Mn, Rb, Ba, W, and Tl were generated to correctly classify wines from each region. In an alternative approach, a pairwise discriminant analysis procedure, not previously used in wine provenance studies, was tested. In this procedure, the classification was done in three steps, with each step classifying a wine as coming from a certain region or not. The combination of elements characterizing wines from a particular region was different in each region. The discriminant functions were based on the following elements: Al, Mn, Rb, Ba, and W for Stellenbosch; Se, Rb, Cs, and Tl for Robertson; and Al, Mn, Rb, Sr, Ba, and Tl for Swartland. After this procedure, the classification of the wines into one of the groups was 100% successful.  相似文献   

13.
Data are presented for 32 elements (Li, Be, B, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Ge, As, Rb, Sr, Y, Zr, Mo, Ag, Cd, Sb, Cs, Ba, La, Ce, Pr, Nd, Sm, Hf, Tl, Pb, Bi) in organic-rich surface soils in Norway, based on samples from 464 sites. By considering geographical distributions based on isopleths, results from factor analysis, and ANOVA of median values from 12 different geographical regions, the contributions from natural and anthropogenic sources are estimated for each element. Long-range atmospheric transport of pollutants from areas out of Norway is a dominant source for Cd, Sb, Pb, and Bi and also a strongly contributing factor for Zn, As, Mo, and Tl. Also V, Ni, Cu, and Ge are somewhat affected, but other factors dominate for these elements. Local point sources of pollution provide significant contributions to soil concentrations of Ni, Cu, Zn, As, Mo, and Cd. The local bedrock is the overriding source of Li, Be, Ti, V, Cr, Mn, Rb, Zr, Cs, Ba, REE, Hf, and probably of Ge and Ag. Surface enrichment by root uptake in plants and return to the soil surface by decaying plant material is particularly evident for Mn, Zn, Rb, Cs, and Ba. These elements show no clear difference between south and north in the country, indicating that their plant uptake does not depend on latitude. In the case of B and Sr, atmospheric deposition of marine aerosols is an important source. Rb and Ag, and to a less extent Mn, Ga, and Ba, appear to be depleted in soils near the coast presumably due to cation exchange with airborne marine cations.  相似文献   

14.
The concentrations of 13 trace elements were determined in soils and Sangiovese grapes collected in vineyard zones of Tuscany (Italy). The purpose was to establish a correspondence among the chemical composition of grape, the geochemistry of vineyard soil and the geolithological features of cultivation zone, and determine the provenance of the grapes by means of their chemical fingerprints. Statistical analysis of Ba, Rb and Sr concentrations distinguished three classes of grapes according to the geochemical and geopedological characteristics of the soils. Grapes with the highest Sr levels grew on high‐Sr soils derived from calcareous, calcareous‐marly and marly‐clayey rocks, whereas the most elevated Rb concentrations characterized the berries cultivated on soils formed from clayey‐marly and sandy‐marly lithologies. Grapes with the highest Ba concentrations grew on soil derived from arenaceous rocks and carbonate lithologies of evaporitic origin. These findings suggested that Ba, Rb and Sr could be used as fingerprints for the chemical traceability of Sangiovese grapes.  相似文献   

15.
利用电感耦合等离子体-质谱(ICP-MS)和电感耦合等离子体-发射光谱(ICP-OES)对不同种植地的青岛大花、札一和马可波罗3个新疆主产啤酒花品种中的22种矿物元素在生长期的含量进行跟踪测定。结果表明,啤酒花对矿物元素的吸收和积累存在"地域差异"和"时间差异",其中Sr、Na、Rb、Li、Ba、Ga、Co和V的含量受种植地的影响较大;但在整个生长周期内,啤酒花对重金属无明显吸收和富集作用。基于22种元素的主成分分析结果进一步证实,前3个主成分的累计贡献率达到84.36%,且由PC 1和PC 2构成的得分散点图可以很好地区分不同产地的啤酒花样本;而由PC 1和PC 3组成的得分散点图主要可以区分啤酒花的"成熟度"。其中,Mg、K、Li、Na可以用来判别啤酒花的产区;Al、Pb、V对于评价啤酒花的成熟度具有较大价值。  相似文献   

16.
Abstract

Apple seedlings from a greenhouse pot experiment, investigating the effects of copper (Cu) and peat amendments on crop performance growing on a Cu‐and potassium (K)‐deficient soil, were characterized for a range of major and trace elements. Concentrations of barium (Ba), calcium (Ca), Cu, iron (Fe), K, magnesium (Mg), manganese (Mn), molybdenum (Mo), sodium (Na), rubidium (Rb), strontium (Sr), and zinc (Zn) in leaf and stem tissues were correlated with treatment and tissue. Addition of Cu, peat and the nature of the tissue had significant impacts on many element concentrations. Generally, increasing Cu resulted in elevated Ba, Fe, Mo, and Sr as well as Cu levels. The presence of peat resulted in reduced levels, generally in both leaf and stem, of Ba, Mg, Mn, Rb, and Zn and increased levels of Fe, K, and Mo. Finally, the vast majority of elemental concentrations were higher in leaf tissue rather than stem, with the exceptions of Na and Zn. Elemental concentration ranges, over all tissues and conditions of added Cu and peat were (mg kg‐1) Ba 9–49, Ca 6380–16340, Cu 2–11, Fe 10–57, K 4070–16950, Mg 900–4260, Mn 22–197, Mo 0.02–0.19, Na 28–124, Rb 0.7–12, Sr 41–58, Zn 18–48.  相似文献   

17.
Mineral concentrations of onions (Allium cepa L.) grown under various conditions, including factors (fertilization, crop year, variety, and provenance), were investigated to clarify how much each factor contributes to the variation of their concentrations. This was because the mineral concentrations might be affected by various factors. The ultimate goal of this study was to develop a technique to determine the geographic origins of onions by mineral composition. Samples were onions grown under various conditions at 52 fields in 18 farms in Hokkaido, Japan. Twenty-six elements (Li, Na, Mg, Al, P, K, Ca, Mn, Fe, Co, Ni, Cu, Zn, Rb, Sr, Y, Mo, Cd, Cs, Ba, La, Ce, Nd, Gd, W, and Tl) in these samples were determined by inductively coupled plasma atomic emission spectrometry and inductively coupled plasma mass spectrometry. Fertilization conditions and crop years of onions caused variations of P, Ni, Cu, Rb, Sr, Mo, Cs, and Tl concentrations in onions; different onion varieties also showed variations in numerous element concentrations. However, the variations of mineral compositions of onions by these factors were smaller than the differences between production places with a few exceptions. Furthermore, Na, Rb, and Cs in group IA of the periodic table, Ca, Sr, and Ba in group IIA, and Zn and Cd in group IIB showed similar concentration patterns by group; this result demonstrated that elements in the same periodic groups behaved similarly in terms of their absorption in onions.  相似文献   

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