岩溶断陷盆地不同海拔植物水分利用效率分析

为探讨不同海拔高度的养分、环境要素与植物水分利用效率变化的关系，以岩溶断陷盆地云南小江流域的乔木、灌木、草本为研究对象，分析水分利用效率和叶片养分浓度随海拔的变化情况。结果表明:（1）研究区内海拔2 000 m处的草本植物的叶片δ13C值最高，2 200 m处的乔木的叶片δ13C值最低；（2）海拔高度对乔木、灌木的植物水分利用效率影响大于草本植物，草本植物的水分利用效率随海拔高度的变化甚微，两者之间的拟合度较小；高值区出现在海拔为2 200 m处的乔木；低值区出现在海拔为2 000 m处的草本植物；（3）不同海拔水分利用效率与叶片N、P浓度的相关性较弱（与叶片的N浓度呈弱正相关，与叶片的P浓度呈弱负相关）；（4）不同海拔水分利用效率与各气候因子的相关性较弱，与多年平均气温、多年平均降雨量、多年平均日照时数均呈弱正相关。      

A STUDY ON THE SOIL RESPIRATION OF THE FORESTS ON GONGGA MOUNTAIN

ＡＮＩＮＴＲＡＣＯＮＴＩＮA STUDY ON THE SOIL RESPIRATION OF THE FORESTS ON GONGGA MOUNTAINtheNational(G19980 40 80 0 )andCAS'sKeyProjectforBasicResearchonTibetanPlateau(KZ95 1 A1 2 0 4;KZ95T 0 2 )     

天山北麓晚全新世环境演变及其人类活动的影响

在天山北麓(坡)不同海拔、不同植被带、不同沉积相选取剖面, 进行14C测年和沉积相、孢粉、粒度、磁化率及烧失量分析, 探讨晚全新世的环境演变. 通过对比艾比湖、大西沟、东道海子、桦树窝子和四厂湖等剖面反映的环境信息, 结果表明: 晚全新世以来, 气候有冷暖干湿波动, 但干旱的总面貌未发生根本变化. 反映在植被上, 山区森林、低山丘陵区草原-荒漠草原、平原区荒漠-荒漠草原的植被景观无根本变化, 但是在森林的上下界限、平原河谷林的发育程度、平原低地草甸的面积上, 随气候的变化而发生波动.平原湖泊受环境变化的影响十分明显. 晚全新世以来, 平原湖泊水面变化频繁, 3.1～2.4 ka BP, 1.7～1.3 ka BP和1.27～0.3 ka BP时期是高湖面阶段.1.7～0.6 ka BP的中世纪, 气候比较湿润, 温暖, 平原湖泊处于高水位期, 1.7～1.3 ka BP期间天山的云杉林带下限下移, 林带加宽, 自然环境处于最好阶段.人为活动只是在近代对环境产生较大影响, 主要表现在对平原地区水系和自然绿洲的影响上, 河流流量减少、流程缩短、尾闾湖消亡、扇缘溢出带北移、地下水位降低, 泉水流量减少等成为普遍现象.人工绿洲取代自然绿洲, 自然绿洲大面积减少, 尾闾湖滨绿洲大面积消亡, 平原河谷绿洲面积减少, 扇缘溢出带绿洲和大河三角洲绿洲为人工绿洲取代.     

五台山高山带植被对气候变化的响应

根据五台山高山带草本群落特征种的生长、分布和高山林线树种的年轮分析,揭示了近20年来气候变暖对高山植被的影响。高山草甸和林线过渡带的某些植物种向上爬升的趋势与同期区域气温升高密切相关。草本群落及其特征种沿垂直梯度的爬升与五台山高山带近年来的增温趋势相符合,进一步说明了高山带植被对气候变暖的响应较为敏感,可作为气候变化的指示体。树木年轮宽度序列分析和响应函数表明夏季降水对五台山的高山带木本植物生长有较大影响。由于夏季温度较高,冻土融化,提高了降水的利用效率,促进了树木生长。根据树轮宽度指数与7月份降水量的相关关系,重建了20世纪五台山地区7月份的降水量,基本反映了其间降水量变化的规律。结果表明:五台山20世纪20年代、30年代中期至40年代是相对比较干旱的时期,30年代初期和50年代是相对湿润期,近年来,降水量有下降趋势。     

新疆伊犁黄土磁化率增强机制差异性分析

本文对处于西风区的新疆伊犁昭苏黄土剖面进行了磁化率和粒度分析,初步探讨了伊犁黄土磁化率增强机制的差异性。研究表明,伊犁黄土虽然粘土含量较黄土高原黄土高,但细粒组分对磁化率的贡献非常有限,粗颗粒组分对磁化率贡献较大,说明磁性载体主要存于粗颗粒组分中。同时研究发现地形、沉积环境、源区矿物组分和气候等多种因素对磁化率产生不同程度的影响。伊犁黄土磁化率成因机制既具有阿拉斯加风速论模式的特点又叠加了黄土高原成壤作用的模式,即使在同一剖面的不同时段两种模式对磁化率增强的贡献也不同,伊犁黄土磁化率增强机制存在着时空差异性。     

青海柴达木盆地林线附近祁连圆柏叶片功能性状的变化特征

林线作为高山系统中郁闭林与无林高山植被带间特殊的生态过渡带, 对全球气候变化极为敏感. 柴达木盆地林线附近的祁连圆柏作为青藏高原东北部高山生态系统中海拔分布最高的单一优势树种, 是研究林线植物响应气候变化的理想材料. 为明确祁连圆柏重要叶片功能性状对林线附近环境变化的响应模式, 分别测定了东、西两个坡向上林线附近(郁闭林、林线和树线)祁连圆柏的叶片干物质含量(LDMC)、单位面积的叶片重量(LMA)、叶片碳稳定同位素(δ¹³C)、叶片单位重量的碳氮含量(C_mass, N_mass)、碳氮比(C/N)、叶片自由水含量(FW)和叶片自由水与束缚水比(FW/BW). 结果显示:LMA、δ¹³C和C_mass在林线附近无显著变化, 但林线和树线的N_mass、FW及FW/BW显著高于郁闭林, 而LDMC和C/N则相反; 在不同坡向上, 西坡LMA显著高于东坡. 此外, FW与LDMC、N_mass显著正相关, 而FW与FW/BW、LMA与C_mass以及N_mass与C/N显著负相关. 以上结果表明, 祁连圆柏作为我国西北高山生态系统中耐旱、耐寒的树种在林线附近并未受到明显的水分胁迫, 其可能主要通过提高叶片自由水含量、光合能力、含氮渗透调节物含量等策略来适应林线附近的恶劣生境, 以保证自身的正常生长发育.     

新疆伊犁黄土化学风化特征及其控制因素

       通过对伊犁盆地昭苏黄土剖面元素地球化学分析,结合与黄土高原典型第四纪风成堆积洛川剖面的对比,对伊犁黄 土常量元素分布规律及化学风化特征进行初步研究发现,伊犁昭苏剖面黄土和古土壤主要元素含量具有较好的一致性,暗 示着沉积后两者所经历的风化作用相似。与黄土高原相比,伊犁黄土和古土壤除CaO,MgO和Na2O,P2O5分别出现较大程度的 富集和较小程度的亏损外,其它常量元素含量的变化趋势基本一致;CIA指数、Na/K比值及A-CN-K图解显示伊犁黄土和古土 壤均经历了低等强度的化学风化作用,弱于黄土高原的洛川黄土及古土壤,黄土和古土壤风化分异作用不明显。气候条件 尤其水热组合模式（降水、温度和蒸发量等）对伊犁黄土化学风化的起着重要的制约作用。     

A magnetic investigation of a loess/paleosol sequences record in Ili area

The pedogenic ferrimagnetic minerals have been considered to be the cause of magnetic susceptibility enhancement in loess deposits distributing in the Chinese Loess Plateau and Central Europe, while “wind intensity” mechanism is proposed to be responsible for the magnetic susceptibility enhancement of loess in Alaska and Siberia. However, the magnetic enhancement mechanism is still open for loess in Ili valley, Xinjiang Uygur Autonomous Region, China. To understand this, we conducted a rock magnetic investigation on Axike section that is located in Ili valley. Results show that transitional stage from magnetic (χ_lf) trough to magnetic (χ_lf) peak corresponds to soil units. The PSD and MD-grained magnetite dominate the magnetic properties of AXK sequences, and the main factor affecting magnetic properties is the concentration of ferrimagnetic fraction. For the “pedogenesis enhancement” and “wind intensity” model, it seems hard to explain the magnetic susceptibility enhancement in this area. For the concentration of fine-grained magnetite in magnetic mineral shows positive relationship with the intensity of pedogenesis, the magnetic parameters of loess deposit in Ili valley can be used to recover paleoclimatic variations.     

The long-term trends (1982–2006) in vegetation greenness of the alpine ecosystem in the Qinghai-Tibetan Plateau

The increased rate of annual temperature in the Qinghai-Tibetan Plateau exceeded all other areas of the same latitude in recent decades. The influence of the warming climate on the alpine ecosystem of the plateau was distinct. An analysis of alpine vegetation under changes in climatic conditions was conducted in this study. This was done through an examination of vegetation greenness and its relationship with climate variability using the Advanced Very High Resolution Radiometer satellite imagery and climate datasets. Vegetation in the plateau experienced a positive trend in greenness, with 18.0 % of the vegetated areas exhibiting significantly positive trends, which were primarily located in the eastern and southwestern parts of the plateau. In grasslands, 25.8 % of meadows and 14.1 % of steppes exhibited significant upward trends. In contrast, the broadleaf forests experienced a trend of degradation. Temperature, particularly summer temperature, was the primary factor promoting the vegetation growth in the plateau. The wetter and warmer climate in the east contributed to the favorable conditions for vegetation. The alpine meadow was mostly sensitive to temperature, while the steppes were sensitive to both temperature and precipitation. Although a warming climate was expected to be beneficial to vegetation growth in the alpine region, the rising temperature coupled with reduced precipitation in the south did not favor vegetation growth due to low humidity and poor soil moisture conditions.     

Lateglacial and early Holocene vegetation and climate gradients in the Nordfjord–Ålesund area,western Norway

Birks, H. H. & van Dinter, M. 2010: Lateglacial and early Holocene vegetation and climate gradients in the Nordfjord–Ålesund area, western Norway. Boreas, Vol. 39, pp. 783–798. 10.1111/j.1502‐3885.2010.00161.x. ISSN 0300‐9483. Modern climate in western Norway shows a strong west–east gradient in oceanicity–continentality (coast to inner fjord) and altitudinal temperature gradients that control the regional and altitudinal zonation of vegetation. To discover if similar gradients existed during the Lateglacial and early Holocene, plant‐macrofossil analyses were made from five lacustrine sediment sequences in the Nordfjord–Ålesund region selected to sample the present climatic gradients. The macrofossil assemblages could be interpreted as analogues of the present vegetation, thus allowing reconstruction of past vegetation and climates. When the five sites were compared, climatic gradients could be detected. During the Lateglacial interstadial, mid‐alpine assemblages with Salix herbacea and S. polaris occurred at the lowland coast and upland inland sites, whereas the inland lowland site had low‐alpine dwarf‐shrub heath dominated by Betula nana, demonstrating a strong west–east gradient in temperature and precipitation and an altitudinal gradient inland. During the Younger Dryas stadial, assemblages at the lowland coast and upland inland sites resembled high‐alpine vegetation, whereas the inland lowland site was warmer with mid‐alpine vegetation, demonstrating west–east and altitudinal temperature gradients. Gradients became less pronounced in the Holocene. The early abundance of Betula nana in the inner fjord sites but its rarity at the coast is striking and reflects the oceanicity gradient. All sites became forested with Betula pubescens a few centuries into the Holocene. This forest was probably close to tree line at 370 m a.s.l. at the coast. Inland, there was no detectable altitudinal gradient, with the tree line well above 400 m a.s.l. reflecting the present pattern of tree‐line elevation.     

新疆罗布泊东延地区--阿其克谷地生态地质环境现状及保护措施初探

阿其克谷地是罗布泊洼地的东延部分.对谷地内生态地质环境的气候环境、水环境、土壤环境和生物环境4个主要因子的调查表明：谷地内气候极端恶劣，属于极端干旱的温带和暖温带大陆性气候;水资源极度匮乏，以地下水为主;土壤类型有石膏棕漠土、盐土和流动风沙土3类，一般没有什么肥力潜力;生物物种贫乏，以超旱生和耐盐生的荒漠群落为主.当前，人类活动对谷内生态环境的影响主要为采矿、旅游、盗猎、放牧等活动.最后提出了树立全局观念，限制人类活动，建立生态环境保护区和水资源开发与涵养并举等生态环境保护建议。     

南极地区数百年来气候变化的冰芯记录对比研究

随着国际横穿南极科学考察计划的实施, 近年来开展了沿中山站-Dome A考察路线的冰芯研究, 获得了伊丽莎白公主地250 a来气候环境变化的高分辨率记录. 通过与Lambert冰川流域西侧有关研究结果的对比, 揭示了该冰川谷地为东南极洲重要气候分界线的特征. 综合南极地区其它地点冰芯记录和冰盖变化研究结果, 发现以小冰期为代表的寒冷期在东南极洲较为明显, 在西南极洲则不明显, 甚或恰好相反, 表现为温暖阶段. 就东南极洲来说, 也存在明显的区域差异: 以Lambert冰川谷地为界, 东部地区, 如Wilkes Land (Law Dome), Victoria Land北部(Hercules Neve)等地, 小冰期冷期比较突出;西部地区, 如Dronning Maud Land和Mizuho高原, 情况不是很明确. Lambert冰川流域是非常特殊的地方, 虽然小冰期冷期也存在, 但1850年前后的显著高温和近100多年来的降温与南极洲其它地方都不一样, 而与南极半岛北侧一冰芯所给出的400 a温度变化记录极为相似, 我们尚不能解释为何如此遥远的两个地点具有很好的一致性而与其它地方则不一致.     

天山托木尔峰国家级自然保护区垂直自然带景观特征分析

根据实地考察和相关参考资料,运用历史文献和统计分析的方法,对托木尔峰国家级自然保护区垂直自然带景观特征进行分析,结果显示：对托木尔峰自然保护区垂直自然带的形成,地形地貌因素起着主导作用,纬度起着次要作用,受地形地貌因素制约的水热条件是形成各垂直自然带景观特征的最重要的物质和能量来源,随着水热条件的垂直变化,从低山带至高山带有规律的出现暖温带荒漠带、温带荒漠草原带、山地草原带、亚高山草甸带、高山草甸带、高山垫状植被带和高山冰雪带.东西走向的天山山脉,南北向深切的冰川和流水地貌,对来自北大西洋和北冰洋的湿润气流起了显著地屏障作用,致使托木尔峰南、北坡具有不同的气候特点,南坡形成了暖温带半干旱和干旱气候.自然景观以温带荒漠、荒漠草原和草原为主,植物种类贫乏,具有耐旱特点,随着海拔高度的增加,植物的荒漠成分逐渐减少,草原和草甸成分逐渐增加,土壤的有机质含量提高,碳酸盐的淋溶作用增强.     

基于主成分分析的青藏高原多年冻土区高寒草地土壤质量评价

土壤质量评价是提高对土壤质量理解的关键环节。为了了解青藏高原多年冻土区高寒草地土壤质量的基本情况,在青藏高原腹地西大滩至安多地区,根据不同海拔梯度和植被盖度共采集了154个土壤样品。通过主成分分析（PCA）法确定了影响青藏高原多年冻土区高寒草地土壤质量的最小数据集（MDS）：全氮、全磷、全钾。根据影响土壤质量的最小数据集对青藏高原多年冻土区高寒草地土壤质量进行评价,得出了不同海拔、不同植被盖度下的土壤质量指数（SQI）。通过对不同海拔、不同植被盖度的土壤质量指数进行对比研究表明：随着海拔的升高,SQI呈增加的趋势,即海拔4 300～4 600 m（0.270±0.043） < 海拔4 600～4 900 m（0.326±0.061） < 海拔4 900～5 200 m（0.410±0.075）;随着植被盖度的增加,SQI也呈现增加的变化趋势,即植被盖度小于50%（0.262～0.265） < 植被盖度大于50%（0.336～0.344）。在分别考虑了有机质、盐分、土壤水分对土壤质量的影响下得出的土壤质量指数值与基于最小数据集得到的土壤质量指数相一致,说明基于主成分分析的最小数据集可以对青藏高原多年冻土区高寒草地土壤质量做出较准确的评价。     

Chronology of cirque glaciation,Colorado front range

Moraines and rock glaciers in Front Range cirques record at least four, and possibly five, intervals of Holocene glacier expansion. The earliest and most extensive was the Satanta Peak advance, which deposited multiple terminal moraines near present timberline shortly before 9915 ± 165 BP. By 9200 ± 135 BP, timberline had risen to at least its modern elevation; by 8460 ± 140 BP, patterned ground on Satanta Peak moraines had become inactive. Although a minor ice advance may have occurred just prior to 7900 ± 130 BP, there is no evidence that glaciers or perennial snowbanks survived in the Front Range during the “Altithermal” maximum (ca. 6000–7500 BP), or during a subsequent interval of alpine soil formation (ca. 5000–6000 BP).Glaciers were larger during the Triple Lakes advance (3000–5000 BP) than at any other time during Neoglaciation. Minimum ages of 4485 ± 100 BP, 3865 ± 100 BP, and ca. 3150 BP apply to a threefold sequence of Triple Lakes deposits in Arapaho Cirque. After an important interval of soil formation and cavernous weathering, glaciers and rock glaciers of the Audubon advance (950–1850 BP) reoccupied many cirques, and perennial snowbanks blanketed much of the area above present timberline; although the general Audubon snow cover had begun to melt from valley floors by 1505 ± 95 BP, expanded snowbanks lingered on tundra ridge crests until 1050–1150 BP, and glaciers persisted is sheltered cirques until at least 955 ± 95 BP. Following a minor interval of ice retreat, glaciers of the Arapaho Peak advance (100–300 BP) deposited multiple moraines in favorably oriented cirques.Interpretation of Holocene glacial deposits in the Southern and Central Rocky Mountains has been hampered by (1) a heavy reliance upon relative-dating criteria, many of which are influenced by factors other than age; (2) the assumption that glacial advances in high-altitude cirques can be correlated directly with alluvial deposition in far-distant lowlands; and (3) the assumption that glacial advances have necessarily been synchronous throughout the Rocky Mountain region and the world. Although Holocene glacier fluctuations in the Front Range are believed to reflect changes in regional climate, the Front Range chronology does not have particularly close analogs in other parts of North America. Better-dated local sequences are needed before the hypothesis of global synchroneity can be adequately evaluated; until synchroneity has been proven, long-distance correlations and worldwide cycles of recurring glaciation will remain unconvincing.     

Responses of typical grasslands in a semi-arid basin on the Qinghai-Tibetan Plateau to climate change and disturbances

Alpine grassland ecosystems on the Qinghai-Tibetan Plateau (QTP) are vulnerable to climate change and anthropogenic disturbances, which may have significant effects on the QTP’s carbon budgets. In this study, vegetation and soil characteristics were compared among alpine grassland ecosystems in a semi-arid basin on the northeast ridge of the QTP (1) among alpine swamp meadow, meadow, steppe meadow and steppe soils, which represent the direction of succession under climate-warming conditions, and (2) among alpine, degraded and tilled meadow soils to investigate the effects of human disturbance. The results showed that (1) if the alpine grassland ecosystems succeed in this direction, climate warming will cause a loss of carbon, and (2) tilling activity also results in carbon loss. Therefore, these results indicate that anthropogenic disturbance regimes that change more rapidly than climate may exert a more profound influence on carbon dynamics and balance. However, the plots that were set in the present study represented only part of the basin due to road accessibility. Relationships between leaf area index (biomass and soil carbon) and fractional vegetation cover × vegetation height from this study are fairly good, which can be applied at regional scale to estimate carbon pools. In combination with detailed information of grassland types, climate and human activities, the effects of climate change and disturbances can be estimated using remote sensing datasets.     

西天山大哈拉军山组火山岩SHRIMP锆石U-Pb年龄及其构造意义

新疆早石炭世大哈拉军山组火山岩由西向东表现出由早到晚的演化规律。伊宁县博尔博松河孟玛热勒林场附近大哈拉军山组底部的英安质晶屑岩屑凝灰岩的SHRIMP锆石U-Pb年龄为359±2Ma,表明西天山西段该组底界时代为晚泥盆世末期—早石炭世之间。岩石地球化学数据统计表明,大哈拉军山组火山岩主要受岩浆结晶分异作用控制,是泥盆纪末期—石炭纪时期洋壳消减、壳幔混熔的产物。其岩石组成、时空分布的变化与天山洋由西向东的俯冲―碰撞过程相对应,不需要对其进行解体。     

Variations in soil properties and their effect on subsurface biomass distribution in four alpine meadows of the hinterland of the Tibetan Plateau of China

To understand and predict the role of soils in changes in alpine meadow ecosystems during climate warming, soil monoliths, extending from the surface to the deepest roots, were collected from Carex moorcroftii, Kobresia humilis, mixed grass, and Kobresia pygmaea alpine meadows in the hinterland of the Tibetan Plateau, China. The monoliths were used to measure the distribution with depth of biomass, soil grain size, soil nutrient levels, and soil moisture. With the exception of the K. pygmaea meadow, the percentages of gravel and coarse sand in the soils were high, ranging from 37.7 to 57.8% for gravel, and from 18.7 to 27.9% for coarse sand. The texture was finest in the upper 10 cm soil layer, and generally became coarser with increasing depth. Soil nutrients were concentrated in the top 15 cm soil layer, especially in the top 10 cm. Soil water content was low, ranging from 3 to 28.4%. Most of the subsurface biomass was in the top 10 cm, with concentrations of 79.8% in the K. humilis meadow, 77.6% in the mixed grass meadow, and 62.3% in the C. moorcroftii meadow. Owing to deeper root penetration, the concentration of subsurface biomass in the upper 10 cm of K. pygmaea soil was only 41.7%. The subsurface biomass content decreased exponentially with depth; this is attributed to the increase in grain size and decrease in soil nutrient levels with depth. Soil water is not a primary factor influencing the vertical and spatial distribution of subsurface biomass in the study area. The lack of fine material and of soil nutrients resulted in low surficial and subsurface biomass everywhere.     

基坑涌水量较大情况下边坡稳定性分析与支护研究

拟建场地位于六枝向斜轴部,裂隙发育,为向斜两翼地下水径流的汇水区。通过抽水试验,确定了水文地质参数,预算地下室开挖1m后,基坑的涌水量为4420.64m3/d。场地开挖后,形成的土质边坡高度为2～3.22m,岩质边坡为2.95～7.03m。由于地下水位埋深为3.00m左右,且基坑涌水量较大,因而地下水对边坡的稳定性影响较大.采用极限平衡法预测东部裙楼的南东面,当后缘裂隙充水高度大于0.57m时,边坡的稳定系数小于1.25,须强制支护,东、西部的稳定系数为2.58,边坡稳定,但仍需进行垂直支护;西部裙楼的南西面的稳定系数为0.83,属不稳定边坡,需进行降水和垂直支护。经过分析,确定基坑岩质边坡为70°,土质边坡为45°。提出了基坑支护方案和土钉墙的支护、施工要求。     

Facies and palaeosol analysis in a progradational distributive fluvial system from the Campanian–Maastrichtian Bauru Group,Brazil

The Upper Cretaceous Bauru Group in south‐east Brazil consists of alluvial strata whose characteristics and distribution indicate a fluvial system developed in a semi‐arid to arid climate. Sections exposed within a 90 000 km² study area in Minas Gerais State (in south‐eastern Brazil) were evaluated using facies and palaeosol analysis to formulate depositional and pedogenic models that may account for geomorphic and climate features. From east to west, the study succession records a gradual decrease in grain size, an increase in the width/thickness ratio in channels, a decrease in the lateral and vertical connectivity of channel deposits, and an increase in overbank deposits. The fluvial architecture indicates a braided channel belt, ephemeral ribbon–channels, and an unconfined fluvial facies from east to west in the study area. The lateral and vertical distribution of facies, stratigraphic architecture and palaeocurrent data suggest proximal, medial and distal portions of a progradational distributive fluvial system. The sedimentary dynamics were marked by the building and abandonment of channels related to processes of aggradation, vegetation growth and palaeosol generation. Macromorphological and micromorphological analyses have identified pedological and mineralogical features that indicate an arid to semi‐arid climate with a provenance from the north‐eastern part of the basin (Alto Paranaiba Uplift). From the proximal to the distal portions of the distributive fluvial system, the palaeosol development is different. In the proximal portion, the palaeosols are absent or poorly developed, allowing a possible general comparison with the present soil order: Inceptisols and Aridisols. In the medial portion of the fluvial system, the palaeosols are well‐developed and characterized by Bt, Btk, C and Ck horizons (Alfisols, Aridisols, Inceptisols and Entisols). Poorly drained to well‐drained palaeosols from the base to the top in the distal plain (Aridisols and Inceptisols) are associated with geomorphic and hydromorphic changes in the fluvial system due to progradational evolution. The genetic relationship between the fluvial architecture and the palaeosols enhances the understanding that the sedimentation and pedogenesis that occurs in different portions of the distributive fluvial system are related to the tectonic and climatic evolution of the basin.