Zur Genese der Marschböden. II. Kalksedimentation,Entkalkung

On the genesis of tidal marsh soils II. Carbonate sedimentation, decalcification A central problem of the tidal-marsh soils is the calcareous deposit of the parent material. On the basis of small-scale, systematic investigations it has been demonstrated in two “key areas” in the Weser tidal flats, that fluviatile and brackish soils are descended from calcareous or not-calcareous sediments. Soils buildet from calcareous sediments shows a low depth and a low rate of decalcification because of a high content of clay and bases as well a permanent high level of groundwater during the development of the soils.     

Initiale Marschbodenentwicklung aus brackigen Sedimenten des Dollarts an der südwestlichen Nordseeküste

Initial marsh soil development from brackish sediments The initial marsh soil development from brackish sediments was investigated in a transect from the tidal flat to the dike in the southeast Dollart (Lower Saxony, Germany). Oxidized morphological features increased from the tidal flat to the dike. Simultaneously the bulk density increased from 0.57 g cm^—3 to 1.12 g cm^—3 and the water content decreased from 78.8 % to 54.9 %. The soils closest to the tidal flat were massive, those closest to the dike had a crumble structure. The clay/carbonate ratio increased slightly from 3.3 to 4.8 in the same succession as well as the C/N ratio from 13.9 to 15.6. Likewise the salinity decreased from 7.8 ‰ to 1.5 ‰ and the dominance of Na was replaced by Ca within the pool of exchangeable and soluble cations. The data indicate initial processes of marsh soil development: structure forming, settlement, aeration, salt and lime loss, decomposition and changing ratios of adsorbed cations. Similar to marine developments the soils will enter the terrestrial phase as carbonate containing soils not characterized by the brackish sedimentation conditions. For the initial development of today old marshland soils (”︁Kleimarshes”) from brackish sediments, in contrast, it is likely, that they were already free of carbonate when entering the terrestrial phase. This is explained by long‐term reduction and oxidation of sulfur and low sedimentation rates.     

Cesium- und Strontiumaustauscheigenschaften von Marschböden

Cesium and Strontium Exchange Properties of Marsh Soils The cesium and strontium exchange properties of some typical marsh soils of the estuary and lower river Weser region were described. Soil samples were taken according to the existing soil maps 1:25000 of Lower Saxony e.g. a “sea marsh soil”. a “brackish marsh soil”, and a “river marsh soil”. The exchange properties were determined by Cs/Ca and Sr/Ca exchange curves (Q/I relations) as generally used in soil potassium research. In addition to the Q/I relations the following investigations were carried out: - Cs and Sr desorption experiments (one time equilibration with Ca⁺⁺ solutions) - Cs and Sr reexchange experiments (eight times equilibration with water, Ca⁺⁺, Ba⁺⁺, and K⁺ solutions) - the naturally-occuring Cs and Sr contents of the soils including amounts caused by imissions or fallout, respectively - clay mineral composition and swelling of layer silicates due to saturation with Ca⁺⁺, Sr⁺⁺, Cs⁺, and K⁺ ions. Q/I relations as well as desorption and reexchange experiments indicated strong cesium and low strontium fixation by the soils investigated. This was considered the reason for the stronger transfer of Sr from soil to plants as compared with Cs. Furthermore, the reexchange experiment revealed nearly complete reversibility of the Sr sorption reactions by equilibration with the divalent cations Ca⁺⁺ and Ba⁺⁺ and some Sr fixation after treatment with K⁺ solutions. However, cesium was much better reexchanged by K⁺ than by Ca⁺⁺ and Ba⁺⁺ ions. This led to the conclusion that Cs fixed in interlayer positions of clay minerals could be remobilized by potassium and ammonium fertilization. The naturally-occuring Cs contents of the soils were found to be below the detection limit of the analytical methods used. The contents of naturally-occuring exchangeable Sr, however, was in agreement with the amounts of “labile Sr” as derived from the Sr/Ca exchange curves. Concerning the cesium exchange properties a clear distinction between “sea and river marsh soils” on the one hand and “brackish marsh soils” on the other hand was established due to differences in clay mineral composition and swelling state of 1:2 layer silicates. The different cesium exchange properties of the two soil groups could also be verified by more or less pronounced hysteresis effects of sorption (Q/I relation) and desorption curves.     

Zu Eigenschaften,Horizontaufbau und Gliederung der „Haftnässepseudogleye”︁

Properties, horizons and classification of the “Haftnässepseudogleye” (Stagnosols periodically waterlogged with capillary water) The term “Haftnässe” (soil wetness due to capillary moisture) can be used in describing soils with Sg-horizons in which long-term waterlogging and anaerobic conditions occur in the absence of gravitational water. “Haftnässe” is caused by water held in pores with an equivalent diameter of 0.2–50 μm by soil-water tension (pF) between 1.8 and 4.2, when the air capacity of the horizons is very low. “Haftnässe” moves primarily by capillary forces and is available to plants (available water). In some soils, the horizon below the Sg-horizon contains large pores, is well aerated and tends to impede the movement of capillary water. This type of horizon is often wetter than the overlying and underlying horizons, due to the presence of capillary water in the immediately overlying Sg-horizon. The symbol “So” is proposed for such horizons. In these soils, in the Sg-horizon reduced iron compounds are oxidized and precipitated, forming rusty mottles. The sequence of horizons developed in the “Haft(nässepseudo)-gleye” (Stagnosols periodically waterlogged with capillary water) typically affects the continuity of the pathways along which capillary water normally moves. The “Haft(nässepseudo)gleye” are divided into two subtypes on the basis of the sequence of horizons in the soil profile:

• Typical “Haft(nässepseudo)gley” (Shn) exhibits a sequence Ah/Sg/(II)So and shows transitions to Luvisol and Glossisol,
• Thick “Haft(nässepseudo)gley” (Shm) exhibits a sequence Ah/Sg and shows transitions to “Stau(wasserpseudo)gley” (Gleysol periodically waterlogged due to perched water), Gleysol, Fluvisol and tidal marsh soil.

     

Carbon content in soil particle size and consequence on cation exchange capacity of Alfisols

Abstract

Many of the cultivated soils of sub‐Saharan Africa typically have a surface horizon low in clay and with a low cation exchange capacity (CEC). In these soils, CEC is largely due to the soil organic matter (SOM). Measurements made on long‐term trials show that changes in CEC and SOM are positively correlated to one another, but not of same magnitude, suggesting that not all of the SOM plays an equal role as regards the soil CEC. To study the influence of the different SOM size fractions on the CEC, soils with or without application of manure or compost coming from trials in Chad and Côte d'Ivoire were separated without destruction of the SOM into five organo‐mineral fractions: “coarse sand”;, “fine sand”;, “coarse silt”;, “fine silt”;, and “clay”; made up of particles of sizes between 2,000 and 200, 200 and 50, 50 and 20, 20 and 2, and 2 and 0 μm, respectively. Fractionation was carried out by mechanical dispersion of the soil, wet sieving of the fractions larger than 20 μm, and decanting of the “clay”; and “fine silt”; fractions. The CEC of these fractions increases inversely with their size. The “clay”; fraction which contains half of the SOM contributes about 80% of the CEC of the soils. The CEC of the fractions is largely a function of their carbon (C) content, but the organic CEC per unit C of the “clay”; fraction appears to be four times greater than that of the other fractions (1,000 as against 270 cmol_c kg^‐1). Applications of manure or compost increase the CEC of the soils by increasing the soil C only when this C increase concerns the fine fractions of the SOM.     

Iron compounds in sulfate-carbonate soils on red-colored Cambrian rocks in the southern Angara region

In some regions of Irkutsk oblast in the southern Angara region, brown carbonate-sulfate soils have been formed on red-colored Cambrian rocks. In the automorphic soils, even a low content of hematite strongly affects the soil color, and the increase in its content only slightly enhances the red color of the soil. The brown color of carbonate soil is due to the partial preservation of lithogenic hematite in the upper part of the soil profile. The abundant gypsum “preserves” the lithogenic hematite in the carbonate-sulfate soil; the oxidation of iron is also hampered in this soil. Important changes occur in the wetted dark solonchak: lithogenic hematite is dissolved, the structure of iron chlorite loses order, and coarse and crystallized magnetite is formed in the humus horizon.     

Thormann,F. C., und Golisch,G.: Erfolg in Förste. DLG-Verlag Frankfurt/Main, 1970, 84 Seiten, 20 Abbildungen,broschiert 7,20 DM

Geological and archaeological investigation of the mode of origin of the marshes in Nordfriesland (Germany) In the bogs between marine sediments and Pleistocene uplands on the mainland of Nordfriesland, saltbearing peat for salt production was dug before, as well as while, the bogs were covered by sediments with high clay content. Additionally, there is not much fresh-water coming from the Pleistocene uplands and carbonate is only preserved in the “Klei” deposited in the resulting holes. These facts show, that the “Klei” was originally calcareous and that it was deposited in water with a high salt content. Therefore one cannot conclude that adsorbed cations and narrow Ca:Mgratio (0.5–1.5) indicate sedimentation in brackish water and deposition of sediments with a low, or indeed, no carbonate content. Hence adsorbed cations and the Ca:Mgratio do not allow the separation of marsh soils from soils of a marine or brackish origin.     

Mineralogical and geo-chemical characterization of a diapiric formation in the North of Spain

We have selected seven profiles located in a diapiric formation in the North of Spain. The profiles have been analyzed for the mineralogy and the chemical composition of original materials, soils developed above them and clay fractions. Three soils formed on basic rock of volcanic origin (ophite) and rich in alterable minerals, three others formed on clay marl and one soil formed on gypsiferous marl. Plagioclases, pyroxenes, vermiculites, and biotites are the main minerals found in the soil samples and ophitic rocks. Biotite, smectite, chlorite and interstratified chlorite–vermiculite make up the predominant mineralogical association in the clay fraction of the soils. Calcite, biotite and on top of all chlorite are the main minerals in the marls and the soils developed on them, with gypsum predominant in the gypsiferous marl. The mineralogy of its clay fraction is comprised mainly of chlorite and biotite. The variations in content of Al₂O₃, TiO₂ and Na₂O in the ophites are considered to be associated with the differences in the evolution of the pyroxenes. The variability of the chemical composition of the Keuper sediments and the soils is attributed more to the chaotic disposition of the Triassic materials in the formation of the diapir than to intense chemical weathering. The low concentrations of silica, iron, and aluminum extractable with ammonium oxalate indicate the low proportion of non-crystalline products. Fundamentally, it is the semiarid conditions in the study zone, together with the processes of extrusion and hydrothermal activity affecting the formation of the diapir, that are responsible for the genesis of the minerals.     

Bodenentwicklung am Rande oligotropher Moore im Raum Berlin

Soil development in the surrounding of oligotrophic mires in the Berlin region Polygenetic soils, surrounding oligotrophic kettle hole mires in the valley and aeolian sand areas of the Berlin region, were investigated. The typical soil catena is formed by the sequence of Ombric Histosol (Niedermoor), Ombric Histosol/Albi‐gleyic Podzol (Moor‐Podsol‐Gley), Albi‐gleyic Podzol (Nasspodsol‐Gley), Gleyic Podzol (Podsol‐Gley), and Dystri‐gleyic Arenosol (Gley‐Podsol‐Braunerde) (German soil classifications in parenthesis). Field and laboratory work showed, that the investigated soils were strongly related to each other and that their development depends on the trophy of the mire and groundwater fluctuations during the Holocene. Compared with the Bh‐horizon of terrestrial soils the Gh‐horizon is nearly free of Fe and Mn, but very rich in pedogenic Al‐oxides and rich in organic matter. The genesis of the soils is explained as follows: 1. The development of different Gleyic Podzols was due to rise of groundwater. Consequently the Bh and Bs horizons of Podzols surrounding the mire were converted to Gh and Gr horizons. 2. Humic substances and Al in the Gh and Gr horizons were not re‐mobilized due to the rise of groundwater, whereas Fe and Mn were reduced and removed by groundwater. 3. At the periphery of the mire Fe was enriched in the Go horizon of the Gley‐Podzols but not Mn. 4. The fact that the mire is completely surrounded by Podzol‐Gleys, indicates, that movement of the groundwater from the central parts of mires towards the periphery is an essential pedogenetic factor.     

Ertragssimulation mit “Ceres Wheat” an Grundwasserböden gemäßigter Klimazonen. Teil 1: Anwendungsgrenzen des Originalmodelles und Modelländerungen

Calibration of the simulation model “Ceres Wheat” under conditions of soils with shallow watertable and temperate climate. Part 1: Limitations in the applicability of the original model and necessary modifications To apply the yield simulation model “Ceres Wheat” under the specific climate conditions of Schleswig Holstein, the following modifications were necessary:

• Wheat development is strongly influenced by climatic conditions. Therefore the model has been adjusted to the temperate climate of Schleswig Holstein.
• The soil water balance routine of the model was originally designed for soils without oxygen deficiencies due to water logging. Routines for shallow water tables and artificial drainage were formulated.
• Due to modifications of the soil water balance routine, the associated nitrogen routine, especially the leaching of nitrate, has been changed.
• The simulation of yield depressions due to excessive water required the introduction of a trafficability delay function and an additional reduction factor for crop development.

All routines concerning the water and nitrogen balances and the quality of simulations have been tested under conditions of coastal marsh soils in Schleswig Holstein.     

Zur Frage der N-Formen im Grund- und Bachwasser aus hydromorphen Böden

N-sources in groundwater and outlet channels of hydromorphic soils NO₃- and NH₄-concentration was observed in the surface flow (1972–74) and in groundwater (1974–76) of the catchment area “Honigau” with a size of 1375 ha. During summer with low surface discharge and groundwater tables high NH₄-concentration was measured as compared to NO₃-concentration. High ammonium content during summer appears to be typical for many hydromorphic soils, as confirmed by N-content in Sphagnum peat soils and marsh soils. During winter season only a correlation exists between surface discharge and NO₃-content in the Honigau area. This correlation disappears during very high discharge levels.     

Contemporary pedogenetic processes in a ferrallitic soil in Uganda,I. Identification

Ferrallitic soils were originally considered to be pedogenetically “dead”, with few pedological processes taking place except perhaps leaching. A study of the Buganda clay loam series, a widespread soil in southern Uganda, showed that although this ferrallitic soil is very highly weathered chemically, two important groups of pedogenetic processes are currently active, differentiating the B from the C horizon. These are alteration of soil structure/physical properties and clay translocation. Leaching and clay mineral transformation are not occurring. It is suggested that the pedogenetic basis for classifying soils as ferrallitic has become outdated and that the criteria used need revision.     

Zur Genese von Schwarzerden auf der Sontheimer Hochterrasse in der Donauniederung bei Ulm

Pedogenesis of chernozems in the upper river terrace of the Danubian river near Ulm (South West Germany) The “chernozem-like” soils in the upper river terrace of the Danubian river near Ulm (FRG) were examinated. Field analyses as well as soil physical and chemical, clay mineralogical and pollen analyses were carried out. The parent material of the soils was identified as loess, on the basis of its texture, clay mineral composition, structure, carbonate content, the presence of loess molluscs, and the location on an upper river terrace with loess findings in the surrounding. Characteristic pedogenetic processes, such as deliming, silicate weathering, formation of oxides and hydroxides, neoformation of clay minerals and clay translocation prove a non-groundwater-influenced development of the soils within at least the last 8000 years. Therefore an accumulation of organic matter under anaerobic conditions during the peat formation in the lower river terrace nearby was not possible. According to this finding, it can be deducted that the humus accumulation may be due to influences of continental climate and forest steppe during the preboreal period, whereby the humus horizons were formed at deeper horizons through bioturbation. After the groundwater level was raised in boreal age, the steppe stage of the soils had ended and the fluctuating levels of groundwater, rich in carbonates, stabilized humic substances. Thus strong degradation of the soils to date was prevented. Therefore the soils under study could be classified as gleyic Chernozems or luvic Phaeozems.     

Organic sulfur forms in mineral top soils of the Marsh in Schleswig‐Holstein,Northern Germany

Little is known about the nature of organic sulfur (S) in soils of the Marsh in Schleswig‐Holstein, Northern Germany. In addition to total and inorganic S, we determined two organic S fractions (ester sulfate‐sulfur and carbon‐bonded sulfur) in 14 aerated mineral top horizons of two salt marshes and ten dyked polder soils of different age. All soils developed from marine sediments. Total S concen‐trations ranged from 153 to 950 mg kg^—1. Organic S was the main S constituent (range from 53 to 99% with a median of 97%). Higher inorganic S levels were found only in the salt marshes due to soluble sulfate (15 to 47%). The younger marsh soils (salt marshes and soils of a polder dyked in 1978) had unique high S contents of 0.9 to 2.4% in their organic matter, whereas the S contents of the organic matter in older marsh soils were at only 0.6%. This S‐rich organic matter is a heritage of a former anoxic marine environment. In most horizons the carbon‐bonded S was the dominant sulfur form. However, both carbon‐bonded S and ester sulfate‐S did not relate to soil age. This limits the benefit of the wet chemical fractionation procedure used for studying the fate of organic S in marsh soils.     

Hydraulic conductivity of calcareous soils as affected by salinity and sodicity. I. effect of concentration and composition of leaching solution and type and amount of clay minerals of tested soils

Abstract

Although there is generally no physical problem with salt‐affected soils when irrigated with saline and sodic waters, physical deterioration of the soils often results when leached with good quality (low salt and low sodium) irrigation water or by rain. Two major mechanisms of swelling and dispersion of clay particles have been proposed to be responsible for reduction in hydraulic conductivity (HC). The type and amount of clay minerals are major factors influencing the swelling and dispersion properties of soil in the presence of saline‐sodic solutions. The study was initiated to improve the understanding of swelling and dispersion processes in response to saline‐sodic conditions, particularly the role of the type and amount of clay minerals of the tested soils and the concentration of the leaching solutions. The study was conducted in a series of two leaching experiments. In the first experimental soil samples were leached with solutions of different combinations of 100 meq (NaCl+CaCl₂)L^‐1 and sodium adsorption ratio (SARs) 5, 10, 15, and 20. In the second, 8 samples of them selected to be leached with solutions of the same SARs of 5, 10, 15, and 20, but the higher concentration of 1000 meq (NaCl+CaCl₂)L^‐1. The changes in the HCs were determined through the concept of “the Sensitivity Index‐SI values”;. In general, solutions with lower concentrations and higher SAR resulted in greater reductions in the soil HC (i.e, SI value), and the SI values and SAR level showed a negative linear relationship. With respect to the regression equations between the SI values and the swelling/dispersion processes, and the relatively coarse texture as well as the mineralogical composition of the tested soils which shows the dominant clay minerals in almost all tested soils is non‐expanding dispersive quartz, illite and chlorite, it may be concluded that the slaking of the soil structure is responsible for blockage of the conducting pores and reduction in the HCs of the tested soils.     

Complex pedogenesis related to differential aeolian sedimentation in microenvironments of the southern part of the semiarid region of Argentina

The aim of this paper is to explain soil genesis and spatial variability in the soil cover of a flat landscape in the southern part of Argentina's semiarid region. Soil survey data indicate random differences in the properties of soils lying within a few hundred meters of one another, as reflected in an intricate distribution pattern which cannot be explained by the climatic theory of soil genesis in a single pedogenetic cycle. This pattern is unrelated to the actual vegetation cover. The soil parent materials consist of a <2-m mantle of aeolian Holocene sediments overlying a thick plio-Pleistocene “tosca” layer (calcrete, caliche). The undulations in the tosca layer are indicative of a paleomicrorelief levelled up to the present surface after the deposition of the Holocene sediments. Soils with fine-textured sandy loess and strong development (Meridiano soil: A–Bw–Ck–2Ckm) occupied a higher position within paleomicrorelief of the tosca layer. Adjacent soils on border or intermediate positions of the petrocalcic paleosurface have more complex profiles with a relict calcic horizon (Vizcachera soil: A–C–2Ck–3Ckm) and coarser texture (silty clayey sand) in the topsoil. In the lower positions of the paleomicrorelief of the tosca layer, the silty clayey sand directly overlie the petrocalcic horizon (El Khazen soil: A–C–2Ckm). The intricate distribution pattern is due to the coexistence of older polypedon (Meridiano soil), remnants of an earlier erosion cycle complexed with two younger soils, one from partial erosion (Vizcachera soil) and the other where total erosion of earlier soils was followed by successive pulses of aeolian deposition (El Khazen soil). The distribution pattern of the three soils thus reflects a complex history involving at least three stages of landscape evolution.     

Distribution pattem,genesis and classification of soils of an arid dune area in Northern Negev

A dune area of 2 km² in the Negev (Israel) with an annual precipitation of 90 mm was mapped. The soils developed from eolic and fluviatile sediments were Arenosols, Calcisols. Solonchaks, Regosols and Fluvisols. The Arenosols of the dunes are more homogeneous in texture and salt content than the soils of the interdunal corridors: Besides the Fluvisols, also the Calcisols, Solonchaks and Regosols are stratified due to episodic flooding by a wadi, and are rich in salts and lime. The soils are of minor development. Aggregation and enrichment of lime, enrichment and movement of salts, and the enrichment of organic substances are indications of soil formation. The distribution of salts within the profiles was calculated by their solubility. High and low soluble salts appear together in thin layers of Calcisols, Solonchaks and Fluvisols, while the most-soluble salts appear in deeper layers. The salts, therefore, must have accumulated by lateral movement, precipitation and temporal flooding. Influence of groundwater can therefore be excluded. The Arenosols also show the same sequence of salt types, indicating the accumulation due to precipitation and eolic mass movement. Abandoned arable land sites did not show any different soil characteristics from the unused soils. On the basis of the distribution of salts in the profiles and soil types genesis and classification of the soils is discussed.     

Clay soils on limestone in South Limburg,The Netherlands, 1. Setting and general characteristics

Detailed soil mapping in the Ransdalerveld area pointed to the occurrence of clay soils of different ages, characteristics and genesis. Three representative soil profiles were therefore selected and studied in detail.In this first of three articles, some observations and conclusions on the distribution, age and characteristics of these soils are presented. The “old” soils, developed on the plateaus in predominantly limestone-weathering residues, are classified as Lithic Hapludalfs, whereas the “young” soils on the valley slopes are classified as Rendollic Eutrochrepts if they lack a loess cover and as Typic Hapludalfs if they have a loess cover. Weathering and soil formation are discussed in the second and third parts.     

Rekonstruktion des Ausgangszustandes und Bilanzierung von Böden einer Moränenlandschaft

Reconstruction of the original composition and balancing of soils developed on glacial till In this paper a method for the reconstruction of the original composition of soils formed on heterogeneous glacial till is described. As an exampel the original contents of carbonates, iron and clay were calculated in two soils. The soils investigated are “Rostbraunerde” under forest and ?Braunerde”? under meadow. The “Braunerde” has been regularly irrigated with waste water for the last 70 years. The heterogenity of the fine earth of the parent material is caused by the successive deposition of materials with varying particle size distribution as well as in situ cryoclastic weathering of the different rock fragments. The reconstruction was calculated from the relation between the above mentioned weatherable components and less weatherable components in the pleistocenic sediments of Berlin. The sorting grade (So, Muller, 1962), median (Md) of the particle size distribution in the 2–600 γ fraction and the contents of coarse sand, Zr and Ti in the fraction 2-2000 pm were considered as unweatherable. The calculations were performed using multi regression analysis. The influence of the pedogenetic processes of decarbonatisation, acidification, clay formation and clay migration as well as the pedological changes resulting from the waste water irrigation were quantified through the comparison between the calculated original and the measured actual contents of the weatherable components.     

Marsh soils of the Karelian shore of the White Sea

This paper studies marsh soils on the Karelian shore of the White Sea. The soil cover has been found to differ on shores of the open, closed, and transitional types. The open shores have mainly marsh primitive and soddy soils. In bays, there are marsh soddy gley and dredged peat gley soils, and the transitional shores have marsh peaty soils. All soils have poorly developed profiles, and their reaction is close to neutral. Organic and organic-mineral layers form depending on the position of a soil above sea level: a sod layer forms in uplands, and peaty and mud layers form in depressions, which are regularly flooded and have a high groundwater level.