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1.
在贵阳市乌当区采集了9种母质(岩)上发育的土壤样品763个,分别测定了土壤的主要理化性质和主要重金属元素含量,通过对比分析表明不同母质(岩)发育的土壤理化性质和重金属含量都具有很大的差异。土壤理化性质的差异性主要表现为:石灰岩、红色粘土、老风化壳和页岩发育的土壤质地粘重。砂岩发育的土壤质地较轻,钙质紫色砂页岩、白云岩、砂页岩和河流冲积物发育的土壤质地适中;石灰岩、白云岩和钙质紫色砂页岩发育的土壤pH值为中性至微碱性。河流冲积物发育的土壤pH值为中性,其余5种母质(岩)发育的土壤pH值为酸性至强酸性;白云岩、钙质紫色砂页岩和河流冲积物发育的土壤有机质含量较高,而砂岩发育的土壤有机质含量较低,其余5种母质(岩)发育的土壤有机质含量介于二者之间;河流冲积物、石灰岩、白云岩和钙质紫色砂页岩等发育的土壤CEC较高,而砂岩发育的土壤CEC较低,其余4种母质(岩)发育的土壤CEC介于它们之间。土壤重金属含量差异性表现为:钙质紫色砂页岩、石灰岩、河流冲积物等发育的土壤中锅、铬、汞的含量较高。而红色粘土、河流冲积物和石灰岩等发育的土壤中铅和砷含量较高,砂岩发育的土壤中5种重金属元素的含量均为最低,其余母质(岩)发育的土壤中5种重金属元素的含量均介于上述之间。通过相关性分析结果表明:研究区域内土壤重金属镉、铬、汞、铅、砷的含量差异主要是由于成土母质(岩)的差异性所致,土壤理化性质的变化则是影响土壤重金属含量的次要因素。  相似文献   

2.
河南省多级地貌特征及与土壤多样性的关系   总被引:2,自引:1,他引:1  
任圆圆  张学雷 《土壤》2019,51(1):142-151
从土壤多样性向地多样性发展符合土壤地理学的研究趋势,选择河南省作为研究区,将地貌这一主要的地学要素加入到土壤多样性的研究中,并用改进的仙农熵公式对多级地貌空间分布多样性及其与土壤多样性的相关性进行探讨。首先,对河南省1︰175万地貌类型图进行矢量化得到地貌类型等级系统;然后,对地貌和土壤的构成组分多样性和2种不同分类体系的分支率进行计算并分析其特征;最后,在3 km×3 km网格尺度下分析地貌和土壤多样性间的相关性。研究表明:河南省共有3个一级地貌,12个二级地貌和37个三级地貌;随着土壤和地貌分类的等级细化,其分类个数和构成组分多样性值均呈上升趋势,即土壤和地貌所有分类单元在数量构成上的均匀程度越来越高;两种分类系统中,土壤分类较地貌分类有更详细的分类体系,且分支率有较大范围的变化;河南省一级地貌、二级地貌和三级地貌的空间分布多样性值和面积值均最大的类型分别是流水地貌、冲积平原和泛滥平坦地,是不同级别的优势地貌类型;一级地貌类型与土类、亚类和土属多样性间存在紧密的相关关系,且以流水地貌与土壤多样性间的相关性最强。  相似文献   

3.
在贵阳市乌当区采集了白云岩、石灰岩、钙质紫色砂页岩等9种母质(岩)上发育的土壤样品763个,分别进行了土壤主要理化性质的测定和差异性分析。结果表明不同母质(岩)发育的土壤理化性质具有很大的差异:红色粘土、老风化壳和页岩上发育的土壤pH值均为酸性至强酸性,有机质和CEC含量中等,土壤质地较粘重;石灰岩、白云岩和钙质紫色砂页岩上发育的土壤pH值为中性至微碱性,有机质和CEC含量较高,质地较为适中;砂页岩和河流冲积物上发育的土壤pH值为酸性至中性,其余理化性质为中等水平;砂岩发育的土壤pH值为强酸性,其余理化性质均较差。  相似文献   

4.
河南省典型土系的特定土层特征与分类研究   总被引:1,自引:0,他引:1  
鞠兵  吴克宁  李玲  陈杰 《土壤学报》2016,53(1):48-57
根据土壤发生学理论,在土壤景观相似的土壤中(如相同母质、相似气候、相同地形以及相似的植物类型和动物活动),土壤的属性具有相似性;然而由于地理环境中复杂的成土因素的影响,土壤绝无完全相同的土壤个体。在划分土壤地理发生分类基层单元土种和系统分类基层单元土系时,特定土层被用于反映土体构型差异。但特定土层类型多样,目前尚处于模糊状态,随着土系划分研究的深入,有必要对其进行分门别类与归纳整理。本文以河南省典型土系为例,梳理和总结了土系划分时涉及的主要特定土层,从特定土层形成根源上将其分为现代成土环境下土壤发生过程形成的、地质成因或地质时期土壤环境下发育形成的和人类活动产生的三个类型,并提出了基于土系概念的特定土层分类与检索体系,旨在使特定土层的概念更为系统、全面、开放,以便于使用。  相似文献   

5.
The development of soil classification systems in Russia has been accompanied by certain changes in the attitude toward the factors of soil formation as criteria for separating soil units at the high taxonomic levels. The works of N.N. Rozov supported the traditional priority of the bioclimatic approach to the separation of soil types and subtypes in the classification systems of 1967 and 1977. In the new classification of Russian soils, the factors of soil formation are taken into account in a “hidden” form, through the diagnostic horizons and features reflecting the facial and zonal changes in the character of the pedogenesis and through the separation of several high-level soil taxa developing under specific combinations of lithological and geomorphic conditions. Ecological matrices illustrating the position of the soil types distinguished on the basis of substantive criteria in the field of soil-forming factors are included in the latest version of the new Russian soil classification system. The idea of these matrices fully corresponds to the logic of the factor-genetic soil classification system developed in the works of N.N. Rozov.  相似文献   

6.
土系划分方法研究——以江苏省新沂样区为例   总被引:1,自引:0,他引:1  
作为土壤系统分类的基层分类单元,土系的划分必须经过实地调查,重视控制层段和特征土层的设立,并选择合适的分异特性作为分类指标。本文选择样区内不同景观单元中的10个土壤剖面,根据中国土壤系统分类的要求,探讨了样区内土壤诊断层、诊断特性及其在中国土壤系统分类中的归属;并在有关土系认识的基础上,探讨了土系划分的原则、依据和具体划分方法,确立了研究区土壤所具有的特征土层,依据①特征土层的种类、排列、厚度,②土壤质地和③土壤有机质含量这三类指标,把样区土壤划分为10个土系。  相似文献   

7.
Under conditions of active volcanism, the soils on different geomorphic positions (from high-mountain landscapes to river valleys) are formed under the impact of periodic ashfalls. The exogenous processes affect the redistribution of volcanic ashes by the elements of the relief, so that the soils of different altitudinal zones have their own morphological specificity. It is suggested that two additional types of volcanic soils should be included in the new Russian soil classification: the type of alluvial volcanic soils in the order of volcanic soils and the type of volcanic lithozems in the order of lithozems. These soils can be considered intergrades between volcanic and alluvial soils and between volcanic soils and lithozems, respectively.  相似文献   

8.
Using the latest version of the international soil classification (WRB 2014/2015) and the classification of soils of Russia (2004/2008), the authors attempted to demonstrate how specific profiles of urban soils in green massifs are classified at different taxonomic levels. The soil profiles were shown in the excursions of the 9th International Conference “Soils of Urban, Industrial, Traffic, Mining and Military Areas” and were discussed by the representatives of national scientific schools. The diversity of the soils studied is determined primarily by the technology of their creation or by the nature of human impact, soil age, properties of the soil-forming rock, and, to a lesser extent, by the type of artificial phytocenosis. By the properties of their profiles, soils are qualified as ones on technogenic deposits (artificial buildings or displaced natural grounds with fragments of soil horizons), buried agrozems and cultural layers. The comparison of two classification systems showed their similarity with respect to the taxonomic level. One can note a similarity of the main solution: are the soils natural or anthropogenic, although the degrees of “anthropogeneity” given in their names may not coincide. The existing differences in the sets of characteristics–qualifiers reflect the genetic trend in the Russian soil classification and strict following the rules in the WRB system.  相似文献   

9.
Strongly weathered red and yellow soils with thick (490–900 mm) humic Al horizons (Haplohumox and Palchumults) derived from sandstones and basic igneous rocks, and occurring near the east coast of Southern Africa, are described and discussed in terms of their distribution, morphology, texture, mineralogy, chemistry, genesis and classification. The high organic matter content (2–5%C) of the Al contributes significantly to a high pH-dependent negative charge, probably to poorer crystallinity of goethite and kaolinite and to the transformation of haematite to goethite. Varying proportions of kaolinite and gibbsite reflect different soil ages within these old landscapes. The yellow colour of aluminous goethite, the main pedogenic iron oxide, is masked in the Al by organic matter and in red B2 horizons by haematite. Temperature may have influenced the broad pattern of occurrence of red and yellow B2 horizons. These soils need not, as previously suggested, have developed from the weathering products of an ancient laterite. Neither Soil Taxonomy nor the South African soil classification system accommodates the soils entirely satisfactorily and possible improvements to the latter are discussed.  相似文献   

10.
Water erosion causes the accumulation of soil material, especially at the bottom slope and in landscape depressions. According to FAO-UNESCO (1990) colluvial soils can be classified as Cumuli-Aric Anthrosols if the minimum thickness of the altered topsoil is 5 dm or more. These soils are characterized by addition of small amounts of soil material that has been incorporated into the underlying material by tillage and/or turbation. As a result of geological factors and land-use intensities, Cumuli-Aric Anthrosols differ markedly in their ecological properties. In the study area ‘Bornhoeved Lake District (Schleswig-Holstein, North-Germany)’ soil patterns have been investigated showing the interdependence of soil landscapes and their soil units by water erosion and accumulation. Examples of various colluvial soils in catenary sequences in the study area are presented. Colluvial soils in the study area are characterized by a layer thickness between 5 and 14 dm and show significantly higher quantities of organic matter, nitrogen and plant-available water in comparison with eroded soils.  相似文献   

11.
Development and application of landform segmentation procedures   总被引:6,自引:0,他引:6  
Landscape-scale approaches to research in soil science are explicitly focused on transfers of components within and between landscapes. Despite wide-spread recognition of the importance of these transfers, the application of landscape-scale approaches has been hindered by the lack of clear, reproducible research designs. Landform segmentation is used to divide natural and human-influenced landscapes into functionally distinct units. A specific type of landform segmentation, landform element classification, was used in a comparative mensurative design to compare the effects of cultivation on soil distribution and soil organic carbon (SOC) storage and in a manipulative design to determine the relationship between N2O emissions and fertilizer rate in a hummocky till geomorphic surface in southern Saskatchewan. Significant transfers of SOC and surface soil from convex shoulder units to lower slope positions occurred over the past 90 years, resulting in a change in the type of soils that occupy these positions at two research sites. The observed pattern is consistent with a tillage translocation dominated surface. The dominant control on N2O emissions in the landscape are spatial differences in water-filled pore space (WFPS) that are strongly controlled by water redistribution. Emissions from drier, shoulder landform element complexes are consistently low throughout the year, whereas a strong positive relationship between N fertilizer rate and N2O emissions occur in the wettest, level depressional elements.  相似文献   

12.
The relationship of geomorphic and climatic history and formation of the ferruginous soils, formed on the acidic Peninsular Gneiss, of the Mysore Plateau, India, is discussed. The profiles studied are found on two different land systems. The soils of the older, fairly smooth landscape are composed of colluvium over truncated laterite profiles, with a gravel layer and a prominent kaolin layer over the weathered rock. These soils show an accumulation of pedogenic haematite grains in the sand fraction and have considerable kaolinite and amorphous ferri-aluminosilicate minerals in the clays. The soils of the younger, rugged landscape have similar clay mineralogy, but do not have a gravel layer, or haematite grains. The influence of the coarse-grained parent rock is seen in the large amounts of quartz gravel. The absence of granulation is attributed to lack of accumulation of iron. The soils have been formed in an earlier, more humid climate than prevails today. The original laterite profiles were formed on a plane surface, and subsequent change in climate has led to change in the land forms and dissection. Truncation of the profiles was followed by deposition of red colluvium over the resistant ferruginous layer. These ancient soils do not fit the criteria for Oxisols in the U.S. classification, but fit well in the French system as ‘Sols Ferrallitiques’, subclass ‘fiablement désatures en (B)’. The soil from a low lying area, formed from colluvium under hydromorphic conditions. is classified as‘Vertisols et Paravertisols'.  相似文献   

13.
14.
湘东地区花岗岩红壤在中国土壤系统分类中的归属   总被引:4,自引:1,他引:4  
为了研究湖南省东部花岗岩红壤在中国土壤系统分类中的归属,选取湘东地区8个由花岗岩母质发育的典型土壤剖面,在对其成土环境、剖面形态特征及其理化性质进行研究的基础上,按照中国土壤系统分类方案,检索出了其诊断层和诊断特性,据此确定了其在中国系统分类中的归属。结果表明,供试的8个土壤剖面包含了淡薄表层、暗瘠表层、低活性富铁层、黏化层等9个诊断层和诊断特性,其在中国系统分类体系中的位置分别为:淋溶土、富铁土和雏形土3个土纲;湿润淋溶土、湿润富铁土和湿润雏形土3个亚纲;简育湿润富铁土、铝质湿润淋溶土、酸性湿润淋溶土和铝质湿润雏形土4个土类;普通铝质湿润雏形土、普通简育湿润富铁土、普通铝质湿润淋溶土、普通酸性湿润淋溶土4个亚类;按照土族和土系划分标准,建立了黏壤质硅质混合型酸性热性-普通铝质湿润雏形土等6个土族和脱甲系(43-CS18)等8个土系。实践表明,目前的土族土系划分标准适用于供试土壤基层分类单元划分。与土壤发生学分类结果相比,土壤系统分类结果更能定量反映出湘东花岗岩母质发育土壤性状的差异,进而客观反映出土壤发育阶段和土壤类型的差异。  相似文献   

15.
Development and Classification of Marsh Soils from the Unterweser Region, West Germany. I. Total Nutrients, Carbonate Content, Exchangeable Cations and Diatom Flora as Indicators of the Role of Sedimentation Conditions in Soil Development This study was carried out to see how much sedimentation conditions determine the properties– in particular the Ca/Mg ratio – of marsh soils (fluvaquents of coastel areas). The following results show, that the marsh soils properties are not determined by different sedimentation conditions: – The vertic fluvaquents don't have a higher clay content than the mollic and aeric fluvaquents – The total (t) contents of P, Ca, Mg, K and Na varied because of different soil development – The Cat/Mgt ratio in soils with CaCO3 was higher than in soils without CaCO3, and – related to the Caa/Mga ratio – it can also be used as a classification characteristic (a = exchangeable) – The Caa/Mga ratio varied greatly because of differences in exchangeable Ca content. Vertic fluvaquents sometimes, but not often, have a higher content of exchangeable Mg than the mollic and aeric fluvaquents. Comparing maps of the Weser area as it appeared at various times in the Holocene with the soil map, shows that the sedimentation pattern is invariably brackish-marine. This is further confirmed by the diotom flora of the soils tested. Thus the properties of marsh soils, long believed to be dependent on sedimentation conditions, are the product of different continuance and intensity of soil development.  相似文献   

16.
砾石覆盖对土壤水蚀过程影响的研究进展   总被引:9,自引:0,他引:9       下载免费PDF全文
 土壤中砾石的存在对水蚀过程有着重要的影响,有关砾石特别是表土砾石覆盖对土壤水蚀影响的研究结果表明,表土砾石对溅蚀分散、细沟间及细沟侵蚀等坡面侵蚀过程有重要影响:1)泥沙溅蚀分散量与砾石覆盖度呈负相关关系;2)砾石覆盖与细沟间侵蚀的关系较为复杂,这取决于表土的结构、砾石的位置和大小以及坡度等因素,当砾石嵌入结皮表土时,二者呈负相关关系,当砾石置于表土之上或嵌入具有结构孔隙的表土时,二者呈正相关关系;3)砾石覆盖对细沟间侵蚀产沙的作用效率与砾石粒径呈负相关关系,砾石置于表土之上的表土产沙量总低于砾石嵌入表土的产沙量;4)表土砾石覆盖能抑制细沟的形成,增加细沟糙度,降低细沟径流速率以及径流的侵蚀速率。鉴于砾石对水蚀过程的重要影响,RUSLE、WEPP和EUORSEM等土壤侵蚀模型预报含砾石土壤流失量时对相关参数做了修正。  相似文献   

17.
18.
Soils with intricate patterns of their humus profiles developing in the neutral-calcium landscapes of the southern taiga of Western Siberia under highly dynamic paleogeographic, climatic, and weather conditions are characterized. The specific features of these soils comprise the diverse modern humus horizons along with the relic ones of different preservation rates, shallow leaching of carbonates, and a weak development of the middle-profile soil horizons. Specifying these organo-accumulative soils is substantiated by their high humus content against the geochemical background of the clayey calcareous parent rocks. The conjugated series of soils reflect different stages of the soil evolution (the humus profile degradation, the development of eluvial process, and the increase of contrasts in the acid-base conditions) and the hydromorphic transformation accompanied by the formation of organic horizons making the humus profile more complicated. In accordance with the diagnostic horizons, the position of the soils studied was determined in the Classification and Diagnostics of Soils of Russia. The relic enrichment of the humus horizon is proposed to be used as a specific feature of these soils.  相似文献   

19.
Processes taking place at different levels of the soil structural arrangement in irrigated and rainfed soils of the Lower Volga region are analyzed. Interactions between these processes and the dependence of their rates on the duration of irrigation are discussed. It is shown that irrigation-induced changes are more pronounced and proceed faster in soils of poorly drained landscapes in comparison with well-drained landscapes. Interaction of the processes taking place at different hierarchical levels of soil arrangement is observed. At the ionic-molecular level, migration and transformation of the composition of soil humus and soluble salts and various exchange reactions take place; at the level of elementary soil particles, the processes of disintegration, peptization, transformation, and the destruction of minerals; at the aggregate level, changes in the water stability of soil aggregates and the degree of soil micro- and macroaggregation; at the level of particular morphological elements, horizons, and pedons, reorganization of soil material (changes in the thickness and bulk density of soil horizons, synthesis and destruction of various neoformations, etc.); finally, at the level of the soil cover pattern, irrigation leads to a higher complexity of the soil cover; the degree of contrast in the soil cover pattern increases, and the soil development at different sites proceeds with different velocities.  相似文献   

20.
不同碎石含量的土壤降雨入渗和产沙过程初步研究   总被引:15,自引:9,他引:15       下载免费PDF全文
碎石的存在改变了均质土壤的某些物理特性,降雨入渗和侵蚀产沙过程也因此受到影响,获取相关知识有助于模拟和预测土石混合介质中发生的水土过程。试验在模拟降雨条件下,对4种不同碎石含量(质量含量分别为0%,10%,20%和30%)的土壤入渗和产沙过程进行了室内研究。结果表明,碎石含量为10%时,土壤入渗率最大,当碎石含量超过10%时,入渗率反而降低;4种不同碎石含量的土壤侵蚀产沙高峰期均出现在降雨初期0~20 min,此后土壤侵蚀产沙相对稳定且在不同碎石含量的土壤间差别不大;降雨过程中,10%碎石含量的土壤侵蚀含沙率一直保持稳定较低水平,其他碎石含量的土壤侵蚀含沙率起初很高并在0~10 min内急剧下降,此后与10%碎石含量的土壤侵蚀含沙率接近。  相似文献   

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