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1.
Systematical status and soil development of the Tschernosem des Oberrheintales and the Smonica of Rheinhessen (W-Germany) The Tschernosem des Oberrheintales and the Smonica of Rheinhessen are discussed respectively to their position in the soil system of the Federal Republik of Germany, as well as in the FAO/Unesco classification and USDA Soil Taxonomy. Both soils are subrelictic, and the recent behavior of the Smonica does not allow it to be placed among the Vertisols. The history of these soils is described as investigated by field work, palynology and micromorphology. Some connecting profiles between the exposed ones have been outlined. 相似文献
2.
3.
Soil organic matter (SOM) was studied in relation to vertic processes (i.e., shrinking/swelling, cracking, vertical turbation,
lateral shearing, gilgai formation) in Vertisols and vertic soils of the North Caucasus in Russia, and Texas and Louisiana
in the USA. Their impact on SOM properties and distribution was analyzed according to various levels of soil organization,
such as soil cover, profile, horizon, and aggregate structure using chemical methods, micromorphology, isotopic analyses,
and physical fractionation. The greatest variations both in the distribution and properties of SOM were found in mature Vertisols
at the level of soil cover including Ctot, organic carbon stocks, stable carbon isotopic composition, and SOM 14C-age, chemical composition. The distribution of SOM at the profile and horizon levels was related to the functioning of Vertisols
during wet-dry cycles. The isotopic and chemical study of densi-granulometric fractions at the aggregate level reflected the
minor role of vertic processes. 相似文献
4.
Nelly S. Raymond Peter M. Kopittke Frederik J. T. van der Bom N. J. Barrow Michael J. Bell 《European Journal of Soil Science》2023,74(5):e13418
Vertisols are important cropping soils in tropical and subtropical areas, but in many regions, decades of cropping has substantially reduced concentrations of plant-available phosphorus (P), especially in the subsoil layers. Phosphorus behaviour in P-depleted Vertisols has received comparatively little attention, and the availability of P following the addition of inorganic P fertilisers at different concentrations is poorly understood. In this study, we evaluated short-term P sorption and desorption behaviour in cropped Vertisols in relation to specific soil physical and chemical properties. We collected the surface and subsurface of 15 Australian soils with a broad range of physical and chemical properties, comprising nine Vertisols, three Ferralsols, two Lixisols and one Calcisol. For each soil, we generated sorption and desorption curves (fitted with a Freundlich equation), determined soil physical and chemical properties likely to influence P sorption and evaluated the relationships between the measured soil properties and the Freundlich equation sorption coefficients. The P sorption curves differed drastically between soils, with the sorption equation coefficients (aS × b) significantly correlated with the P buffering index (PBI) and clay content. Clay content itself was correlated with citrate-extractable Fe and Al oxides and BET surface area. Vertisols formed on basaltic parent materials had greater Fe and Al oxide concentrations, resulting in an overall greater P sorption capacity. Sorption and desorption hysteresis were mostly small. The reacting materials in these soils probably had limited ability to continue to react with P. The Vertisols differed in their capacity to replenish P in the soil solution by desorbing different proportions of previously sorbed P, although the proportion of desorbable P generally increased with greater concentrations of sorbed P. These results suggest that for fertiliser management in these soils, smaller volumes of P enrichment combined with higher P concentrations may result in a greater P recovery by the crop. 相似文献
5.
淮北平原的变性土的形成和演化 总被引：3，自引：0，他引：3
The objectives of the present paper are to restore soil-forming environment of the Vertisols,to reveal their regularities of formation and evolution and to found soil chronology.In regard to formation and evolution of the Vertisols in the Huaibei Plain,they have undergone 3 cycles of deposition-formation during different geologic time (Q3^3;Q4^2 and Q4^3).Therefore,they are considered as the soils developed on heterogeneous parent material.The Vertisols as a paleosol can be divided into relict Vertisols and buried Vertisols.The former is shajiang black soils called by local people,the latter is shajiang black soils underlying Warp soil or warp soil horizon. 相似文献
6.
《Communications in Soil Science and Plant Analysis》2012,43(9-10):1291-1298
Abstract Heavy clay soils with swell‐shrink properties comprise most of the arable land in northern Jordan. These soils are classified as Vertisols. Vertisols occupy a large and important part of the agricultural land in Jordan where rainfed agriculture is practiced. Five sites were selected to represent Vertisols occurring in different precipitation zones. Soil characterization was carried out to provide useful information to understand the genesis and behavior of these soils. Vertisols in northern Jordan occur on flat to gently sloping plains. Clay, silt, and sand fractions were uniformly distributed indicating active pedoturbation. Clay content is moderate to high, and the higher the rainfall the higher the clay content. The high cation exchange capacity (CEC)/clay ratio suggest montmorillonitic and mixed mineralogy. Calcium (Ca) was the most dominant extractable cation followed by magnesium (Mg), sodium (Na), and potassium (K). The similar patterns of distribution for the electrical conductivity values and soluble cations throughout the studied soil sites indicate the low leaching rate, eluviation, and illuviation processes within these studied sites. All soils belong to the Haploxererts soil great group. 相似文献
7.
The Vertisols of the Purna Valley, which cover the districts of Amravati, Akola and Buldhana in the state of Maharashtra, India, lack any perceptible evidence of salt efflorescence on the soil surface which would indicate the presence of salt, but the drainage conditions are poor. The limited data available indicate that the adverse physical condition of the soils is due to their poor hydraulic conductivity (HC), which is impaired by sodium in the exchange complex. However, the factors and processes that are inherently related to the development of sodicity in these shrink-swell soils are not yet understood. In order to establish the cause-effect relationship, eight Vertisol pedons from methodically selected sites were studied morphometrically in the field, and for their sodicity-related physical and chemical properties in the laboratory. The soils are deep, calcareous, clayey and very dark greyish brown to dark brown in colour. Cracks extend up to the slickenside zones in soils of Pedons 1–3 in the northeastern area of the valley, while they cut through the slickenside zones in soils of Pedons 4–8 in the southwest. The slickenside faces were larger in the soils of the southwest than in those of the northeast. All these soils meet the specifications of the Vertisols order of soil taxonomy. Saturation extracts of the soils had very low electrical conductivity (ECe ⩽ 2 ds m−1). They ranged from moderately alkaline in the northeast, Pedons 1–3, to strongly alkaline in the southwest, pedons 4–8. In soils from the northeast the exchangeable sodium percentage (ESP) was less than 5 throughout the depth of the pedons, whereas in other soils it was up to 6 in the surface horizons and between 7 and 26 in the subsoil horizons; four of these soils qualified as sodic according to the criteria of the United States Salinity Laboratory. The inherently low hydraulic conductivity was due to the dispersion of clay particles caused by a high percentage of exchangeable magnesium (EMP) in the highly smectitic soils, and also to a slight increase in ESP (⩾5). The results of this study suggest that ESP 5 should be used as the lower limit for sodic subgroups of Vertisols, rather than ESP 15 as given in Keys to Soil Taxonomy (Soil Survey Staff, 1994). This is because there are severe limitations to the use of such soils owing to the development of adverse physical conditions even at such a low ESP. The authors emphasize the need to keep this fact in mind during future land resource management programmes on the soils of this valley as well as on similar soils occurring elsewhere. The development of sodicity in the soils of the southwestern part of the valley has been attributed to the semi-arid climatic conditions that have induced the pedogenetic process of depletion of calcium ions from the soil solution in the form of calcium carbonate, thereby resulting in an increase of both the sodium adsorption ratio (SAR) and the ESP with pedon depth. This chemical degradation, which affects the sodicity of Vertisols, appears to be a basic process that needs to be recognised in the future along with those already described as natural processes of soil degradation. 相似文献
8.
Moralistic soils (vertic and non-vertic black clays) were sampled along a 200 m top sequence in the Transvaal Highveld, South Africa. The Milk wood soil on the upper part of the margalitic top sequence has an Al horizon which lacks both slickensides and self-mulching properties but has strong blocky structure, the others are all self-mulching (i.e. Vertisols). The Vertisols differ in some morphological properties such as the absence (Mngazi series) and presence (Arcadia series) of pedogenic calcite accumulation, both overlying decomposed dolerite, whereas the third member from a red-black centenary sequence is calcareous with a gleyed subsoil horizon. Chemical and XRD analysis suggest that the clays of the Vertisols comprise mainly a partly chloritized iron-rich smectite with Ie > Mg + Al in the octahedral layer (and interlayer positions), while in the upland Milkwood soil intergradient halloysitic clay occurs in addition to a more‘open’structured chloritized iron smectite. The mineralo-chemical results and the geomorphic data suggest that the genesis of these soils is controlled primarily by the internal soil water regime. 相似文献
9.
Five variants of the distribution of clay (<0.001 mm) and physical clay (<0.01 mm) fractions along the vertical profiles of Vertisols (slitozems) and vertic soils (slitic subtypes of different soil types) from the European part of Russia are distinguished: (1) accumulative, (2) even, (3) regressive, (4) with a maximum in the middle-profile horizon and with their approximately equal contents in the upper and the lower horizons, and (5) eluvial–illuvial. These distribution patterns are related to the lithological specificity of sedimentation and formation of parent materials composed of swelling clays of different geneses and ages. Solonetzic, eluvial- gley, and solodic processes contribute to the development of the eluvial–illuvial and, partly, regressive variants of clay distribution. All the five variants with a predominance of the even distribution pattern can be found in Vertisols. Most of Vertisols in the European part of Russia have a medium clayey or a heavy clayey texture in the entire profile. The regressive distribution pattern is typical of the group of vertic soils. In the upper horizons of Vertisols, where slickensides do not form, the texture is usually heavier than that in the analogous horizons of vertic soils. The middle-profile and lower horizons with slickensides have similar statistical distributions of particle-size fractions in Vertisols proper and in vertic soils. However, in Vertisols, a tendency for a more frequent occurrence of the soils with a higher content of the clay fraction and with a higher portion of this fraction in the physical clay fraction is observed (as compared with the vertic soils). 相似文献
10.
Earlier studies on soil degradation in Vertisols of the Purna Valley of central India indicated that the semiarid climate characterized by a mean annual rainfall (MAR) of 875 mm and a tropustic moisture regime is responsible for the development of calcareous sodic soils. Recent observations, however, indicate that in the adjacent east upland of the Purna Valley, namely in the Pedhi Watershed, Vertisols have drainage problems, although the area receives a higher MAR than the Purna Valley, the total MAR being 975 mm. The Pedhi Watershed covers an area of 44 321 ha, and is characterized by a tropustic moisture regime and a hyperthermic temperature regime. Vertisols of the Pedhi Watershed are deep, calcareous, clayey and very dark greyish‐brown to dark yellowish‐brown in colour. Vertisols occur on both microhigh (MH) and microlow (ML) positions. The distance between the MH and ML positions is approximately 6 km and the elevation difference is 0.5–5 m. Cracks > 1 cm wide extend down to the slickenside zones in soils of ML whereas they cut these zones in some soils in MH positions. The soils of the MH positions are strongly alkaline and those of ML are mildly alkaline. The present study attempts to relate the distinctly different morphological and chemical properties of Vertisols in the MH and ML positions to pinpoint the prime factor responsible for the impairment of drainage on the basis of physical, chemical, mineralogical and micromorphological data. These data were obtained from 13 Vertisol pedons of methodically selected sites in the Pedhi Watershed. Despite their similar coefficient of linear extensibility (COLE), volumetric shrinkage potential (VSP), clay contents and amounts of fine smectite clay, the plasmic fabric of the slickenside horizons in soils of ML is porostriated, whereas in soils of MH it is stipple speckled to mosaic speckled, indicating weak plasma separation. The soils have both pedogenic and non‐pedogenic calcium carbonates (CaCO3). The semiarid climate induces the precipitation of CaCO3 with a concomitant development of subsoil sodicity. The degree of development of sodicity (Exchangeable sodium percentage (ESP) ≥ 5) is more in soils of MH as evidenced by the higher amount of pedogenic CaCO3 (PC). The lack of water in soils of MH position is the reason for weak swelling of smectite, for larger amounts of PC, for higher alkalinity and sodicity, and for cracks cutting through the slickenside zones. Formation of sodic Vertisols in MH alongside non‐sodic Vertisols in ML positions is a unique phenomenon. It develops because of microtopographic differences which modify distribution of water across the landscape and facilitate greater penetration of rainwater in ML positions. The development of sodicity due to microtopographic differences assumes a great importance when a future land resource management programme on Vertisols in the higher MAR zone of overall a semiarid climate is considered. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
11.
Data on the morphology and radiocarbon ages of humus of dark vertic quasigley nonsaline clayey soils with alternating bowl-shaped (Pellic Vertisols (Humic, Stagnic)) and diapiric (Haplic Vertisols (Stagnic, Protocalcic)) structures are discussed, and the genetic concept for these soils is suggested. The studied soils develop on loesslike medium clay in the bottom of a large closed depression on the Eisk Peninsula in the lowest western part of the Kuban–Azov Lowland. The lateral and vertical distribution of humus in the studied gilgai catena displays a lateral transition of a relatively short humus profile of the accumulative type with a maximum near the surface and with a sharp increase in 14C dates of humus in the deeper layers within the diapiric structure to the extremely deep humus profile with a maximum at the depth of 40–80 cm, with similar mean residence time of carbon within this maximum, and with a three times slower increase in 14C dates of humus down the profile within the bowl-shaped structure. The development of the gilgai soil combination is specified by the joint action of the lateral–upward squeezing of the material of the lower horizons from the nodes with an increased horizontal stress toward the zones a decreased horizontal stress, local erosional loss of soil material from the microhighs and its accumulation in the adjacent microlows, leaching of carbonates from the humus horizons in the microlows, and the vertical and lateral ascending capillary migration of the soil solutions with precipitation of calcium carbonates in the soils of microhighs. 相似文献
12.
ZHANGMIN LIULIANG－WU 《土壤圈》1993,3(1):81-88
The ages of organic matter of some dark-colored horizons and calcareous concretions in some Vertisols from tropical,subtropical and warm-temperate zones of China were studied using radiocarbon dating method.The relationship between soil age and genesis of Vertisols was also expounded based on the study of their genetic characteristics and micromorphological features.The results show that although Vertisols have developed for a relatively long time,their weathering and soil forming process are weak and young with little horizonation.This is closely related to their special grochemical soil forming environment.Low-lying terrain,heavy texture,clay minerals dominated by montmorillonites and alternative drying-wetting climate give rise to the vertic features expressed in intense swelling-shrinking and cracking-closing in soils.As a result,the soil development and soil leaching process are resisted,and the climatic effect on the horizonation is impeded.Moreover,pedoturbation eliminates the horizonation in the upper part of soil profile,and postpones their evolution into zonal soils.So vertisols show certain pedogenic inertia and stay at relatively young developmental stage.Therefore,Vertisols are intrazonal soils dominated by local soil forming factors such as the relief and parent materials. 相似文献
13.
金沙江干热峡谷中退化的土壤生态系统生物学特征初探 总被引：4，自引：0，他引：4
Distribution characteristics of soil animals,microorganisms and enzymatic activity were studied in the dry red soil and Vertisol ecosystems with different degradation degrees in the Yuanmou dry hot valley of the Jinsha River,China.Results showed that Hymenoptera,Araneae and Collembola were the dominant groups of soil animals in the polts studied.The numbers of groups and individuals and density of soil animals in the dry red soil series were higher than those in the Vertisol series,and the numbers of individuals and density of soil animals decreased with the degree of soil degradation.Bacteria dominated microbiococnosis not only in the dry red soils but also in the Vertisols.Microbial numbers of the dry red soil series were higher than those of Vertisol series,and decreased with the degree of soil degradation.The activities of catalase,invertase,urease and alkaline phosphatase declined with the degradation degree and showed a significant decline with depth in the profiles of both the dry red soils and the Vertisols,but activities of polyphenol oxidase and acid and neutral phosphatase showed the same tendencies only in the Vertisols.It was concluded that the characteristics of soil animals,microorganisms and enzymatic activity could be used as the bio-indicators to show the degradation degree of the dry red soils and Vertisols.Correlation among these soil bio-indicators was highly significant. 相似文献
14.
N. B. Khitrov 《Eurasian Soil Science》2016,49(5):489-497
Different hypotheses about the genesis of gilgai microtopography and corresponding soil complexes with clayey swelling soils are considered in this review. Their diversity is stipulated by specificities of the objects themselves and by the history of studies of the composition, properties, regimes, and landscape conditions of the areas with Vertisols in different countries. Most of the hypotheses about the genesis of Vertisols with the gilgai microtopography suggest that strong swelling–shrinking processes take place in these soils in the course of moistening–drying cycles; the origin of shear stress in the soils, its spatial patterns, and the particular ways of translocation of the soil material are discussed. At the early stage of Vertisol studies, a hypothesis about the leading role of the process of “self-swallowing” of the soils as a result of filling of open cracks with the material from the upper soil horizons was popular. However, numerous facts suggest that the intensity of this process is relatively low, so that it cannot play the major role in the gilgai formation and cyclic changes in the thickness and properties of the soil horizons in Vertisols. Another important mechanism is the uneven moistening and drying of the whole soil volume resulting in the irregular distribution of inner tensions in the soil with the development of shear stress and plastic deformation of the soil mass. The hypotheses suggested in the recent decades are based on the models of soil mechanics. A number of hypotheses consider possible alternation and duration of evolutionary stages of the development of Vertisols with the gilgai microtopography. 相似文献
15.
At present precise information on the b-fabric of Vertisols is inadequate for gaining a comprehensive knowledge about such soils formed in alluvium of basic igneous and metamorphic rocks and spread in varying agro-climatic zones of peninsular India. The aim of the present study, on five benchmark Vertisol series (Sarol, Aroli, Nimone, Bellary and Kovilpatti), was to assess the possible reasons for differences in the b-fabric of the subsoils despite their common shrink-swell properties, as evidenced by the presence of sphenoids and/or slickensides, and similar clay contents and amounts of fine clay smectite. In Sarol and Aroli soils from the sub-humid region, the b-fabric is porostriated, whereas in Nimone and Kovilpatti soils of the semi-arid and Bellary soils of the arid regions the fabric is either mosaic-speckled or granostriated, indicating weak plasma separation, a result of restricted swelling of clays. The related distribution pattern of the s-matrix in all these soils was open porphyric. Recent literature has suggested that weak plasma separation is an effect of dissolution and crystallization of calcite. However, generally low concentrations of soluble calcium (c. 1 mmol dm?3) in soil solutions of Vertisols in arid and semi-arid agroclimates suggest that the presence of calcite does not guarantee the presence of sufficient soluble calcium to impair swelling of clays by contracting the diffuse double layer. Weak plasma separation in Bellary and Kovilpatti soils compared with Sarol and Aroli soils is explained in terms of a decrease in the internal surface area of fine smectite, as evident from a very high degree of chloritization in smectite interlayers, and smaller proportions of coarse smectite. In Nimone soils the weak plasma separation is primarily due only to a decreased internal surface area of fine smectite. 相似文献
16.
Karunakaran Karthikeyan Duraisamy Vasu Pramod Tiwary Andrew M. Cunliffe Padikkal Chandran Sankar Mariappan 《Archives of Agronomy and Soil Science》2019,65(7):968-979
Cotton (Gossypium sp.) is a major crop grown under rainfed conditions in Vertisols and associated soils in semi-arid tropical (SAT) regions of Peninsular India. In recent years, cotton productivity has declined due to various biophysical factors including pest and diseases, seasonal water stress soil degradation and poor crop management practices. In this study, we compare two methods for evaluating the suitability of Vertisols for cotton in contrasting two agro-ecological regions viz., sub-humid moist (SHM) region and semi-arid dry(SAD) were characterized. Twelve cotton growing Vertisols (seven from SHM and five from SAD) were evaluated for their suitability for cotton cultivation using soil quality index (SQI) and modified Sys-FAO method. SQIs were calculated using the weighted additive index from transformed scores of selected indicators by principal component analysis. For Sys-FAO method both biophysical and soil characteristics were considered for suitability evaluation. We found that the soils of SHM region were moderately suitable for cotton cultivation with soil moisture as the major limiting factor, whereas the soils of SAD region are marginally suitable due to high exchangeable sodium percentage and poor hydraulic conductivity. From this, it may be concluded that the weighted SQI has better agreement with the cotton yield. 相似文献
17.
The N loss from Vertisols was estimated by measuring the loss of 15N-labelled urea N under conditions that promote NH3 volatilization. Urea granules were placed on the top of 150-mm deep soil columns (Vertisols) collected from three sites with a range in pH, electrical conductivity, and cation exchange capacity. There were two contrasting moisture treatments, one near field capacity (wet) and another with intermittent wetting of the soil surface before allowing the columns to dry (moist-dry). The results indicated that losses were influenced markedly by pH and moisture treatment, being 29.5, 33.5, and 33% from the wet soils and 37, 42, and 40.5% from the moistdry soils with pH values of 7.7, 8.2, and 9.3, respectively. These observations clearly indicate that broadcasting of urea on the surface of Vertisols may cause substantial N losses. 相似文献
18.
The effect of long-term irrigation with untreated sewage effluents from Mexico City on soil properties and heavy metal adsorption behaviour of soils at Irrigation District 03 in the Mezquital Valley, Central Mexico, was studied. General soil parameters of 25 samples from Ap-horizons of Mollic Leptosols and Eutric Vertisols taken at sites which have been under irrigation for different periods of time were compared with samples from fields under rainfed agriculture. The adsorption of Pb, Cd, Cu and Zn was analysed in 8 selected samples by batch experiments. The long-term irrigation of soils with untreated sewage effluent has increased the contents of total (TOC) and dissolved (DOC) organic carbon in Ap-horizons of Leptosols and Vertisols, and diminished the contents of manganese oxides in Vertisols. This influences the heavy metal adsorption behaviour of both soils, since DOC enhances metal solubility at low loading rates and TOC improves metal adsorption capacities at high loading rates. The possibility of an increase in the chloride content in soils due to wastewater irrigation and its relation to higher Cd mobility are discussed, as is the importance of humus balance control through oriented management practices in order to minimize heavy metal mobility in soils, which have been under irrigation with wastewater during long periods. 相似文献
19.
《Communications in Soil Science and Plant Analysis》2012,43(3-4):521-527
Abstract Modified version of a dichromate digestion procedure, earlier found suitable for simultaneous determination of organic carbon (C) and potentially mineralizable nitrogen (N) in soils, was evaluated for total N determination in 44 diverse soil samples from the semi‐arid region of India. The soils belonged to Vertisols and Alfisols and had a wide range in total N contents. The method involves digestion of the soil sample with an acidified dichromate solution for 30 minutes in a digestion tube in a block digester preheated to 165°C followed by determination of N in the digest by steam distillation procedure. The efficacy of the dichromate procedure for determining total N differed for the two soil types. Excellent correlations were observed between the values of total N obtained by the dichromate procedure (Dichro‐N) and by Kjeldahl method (Kjeldahl‐N) for Vertisols (R2=0.995; n=21) and Alfisols (R2=0.952; n=23). The regression equations describing the relationships between the two soil types can be used to estimate Kjeldahl‐N from Dichro‐N. Both Kjeldahl and the proposed acid dichromate methods were found to be more precise in determining total N in Vertisols than Alfisols. The proposed procedure is rapid and simple and can be used for routine total N determination especially, in soils such as Vertisols. Based on our results the acid digestion procedure certainly deserves a wider evaluation with a range of soil types. 相似文献
20.
The role of rock fragments in crack and soil structure development: a laboratory experiment with a Vertisol 
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下载免费PDF全文 A large number of factors that influence soil surface cracking behaviour in swell‐shrink soils have been studied, but there are few studies on the influence of rock fragments on crack development. Effects of rock fragments have been investigated with reference to the soil pore system but they have mainly been studied indirectly through measurements of water flow and/or bulk density changes. A laboratory experiment was carried out with repacked soil samples that were prepared by adding rock fragments of three different sizes (2–4, 4–8 and 12–16 mm) to a Vertisol at two different rates (10 and 25% by volume). Soil image analysis procedures were applied in order to describe quantitatively the network of surface cracks and the pore system to a depth of 8 cm below the surface, which developed after wetting‐drying cycles. Mean values and standard deviations of surface crack or pore widths decreased with the increase in rock fragment content and the decrease in rock fragment size, while the density of the ‘skeleton’ of the crack and pore networks increased. Rock fragments also induced vertical homogenization of the soil structure. The number of rock fragments was a key factor in determining some crack network characteristics, inducing inverse variations in mean width and skeleton density of the crack or pore network. Overall results suggested that rock fragments acted as triggering points for crack and pore development in Vertisols. The findings of this work provide a contribution to the understanding of the mechanisms of crack network and soil structure development that are induced by stones in swell‐shrink soils. 相似文献