Zur Genese der Marschböden. I. Der Einfluß von Sediment- und Bodengefüge

On the genesis of tidal marsh soils I. The influence of sediment- and soil-structure The significance of sediment structure for soil structure has often been disregarded when discussing the properties and genesis of tidal marsh soils. After defening several terms that are often misinterpreted, three types of tidal-marsh-soils with different structure are described: 1 . the typical clayey tidal-marsh-soils with very various aggregate structures: The well aired and permeable “SEEMARSCH” (marine-tidal-marsh-soil) with polyhedral and prismatic structure, which is formed from the flaky “card-house” structure of marine sediments rich on salt; the densely paked “BRACKMARSCH” (brackish-tidal-marsh-soil), whose moisture is due to perched water, which coarse prismatic to columnar structure, which is formed from the mainly horizontally orientet structure of brackish sediments due to dispersion; the moderately permeable “FLUSSMARSCH” (tidal-river-marsh-soil), whose wetness is often due to groundwater, with medium to coarse prismatic structure, which is formed from the finely aggregated structure of perimarine tidal-river sediments; 2 . the tidal marsh soils poor in clay, rich in silt and very fine sand with coherent structure and low air porosity, due to a strong tendency towards puddling of the top soil by raindrops, causes the formation of “HAFTNÄSSEMARSCH” (marsh soil whose moisture is due to capillar water); 3 . the tidal-marsh-soils rich in plant remains, clay and with a high level of groundwater often extremly acid, with coherent structure, which formed the generally highly permeable “ORGANOMARSCH”. The conditions of formation of these soils and the soil parameters are discussed also.     

西藏高原土壤多元发生的微形态研究

自上新世末以来,随着西藏高原的隆起和多次冰川作用,作为成土因素的气候、植被、地形、水文等条件发生了剧烈的演变,从而对西藏高原土壤的发生、演化产生重要的影响.土壤大形态研究表明,西藏高原土壤广泛地显示有明显的组合剖面,突出表现在这些土壤剖面中存在有黄棕或棕带红色的、与其上下土层无发生上联系的、在暖湿气候条件下形成的土层;或者在某些现代陆成上壤剖面中存在有水成土的残遗特征等,这些形态特征在很大程度上说明了西藏高原土壤多元发生的客观存在.     

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.     

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.     

Methane dynamics of landfill cover soils and aspects of their classification

The methane dynamics of soils covering a landfill in Oldenburg, Lower Saxony, was investigated in 1996. The methane concentration was often < 20 nmol (dry g)^?1 within the cover layer and up to 9950 nmol (dry g)^?1 within the refuse body. The methane production rates correlated positively with the methane concentrations and were mostly < 10 nmol (dry g)^?1 d^?1 within the cover layer and up to 1090 nmol (dry g)^_1 d^_1 within the refuse body. The methane oxidation rates varied between 38.0–2310 nmol (dry g)^?1 d^?1. The methane emission rates showed values of up to 574 mol m^?2 h^?1, but in two cases no emission of methane was found. The data indicate that the methano-genesis of the deep refuse layers did not substantially affect the methane behaviour of the upper soil sections. It is likely that the emission of methane from landfills can be reduced by thick well aerated cover layers. The term “Reduktosol” for landfill soils is critically discussed.     

The genesis of vertisols with gilgai microtopography: A review

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.     

Genesis of red and dark brown soils on basaltic parent materials near Armidale,N.S.W., Australia

Morphological, physical, chemical and mineralogical data are presented for contiguous euchrozem (nitosols) and chocolate soils (cambisols) developed on basaltic parent materials in the Armidale district of northern New South Wales. The genesis and distribution of the different soils classified at great soil group and series level are related to parent material and topography. The dark brown chocolate soils associated with the modern surface overlie a uniform parent material of partly weathered alkali-olivine basalt. The red euchrozem soils, although having morphological and mineralogical properties associated with intensive weathering and long term soil genesis, have also developed on the modern surface under a moderate leaching regime. They are derived from re-exposed, highly weathered, sesquioxidic, interbasaltic lapilli tuffs and underlying basalt which were probably transformed under a different climate in Pliocene—Pleistocene times. The study showed further that reddish chocolate soils are not necessarily the uppermost member of a sequence of soils developed on partly weathered basalt.     

Effect of Organic matter application on the fate of 15N-labeled ammonium fertilizer in an upland soil

Abstract

The clay mineral composition of two “terra roxa estruturada” (TRE) soils occurring in the tropical rain forest and tropical forest/savannah transition zone, and a reddish brunizem in the savannah/semi-arid transition zone was studied comparatively in the southeast Amazon region.

Kaolin minerals were dominant in these soils, and hematite and goethite were found in the clay fraction. A small amount of 2 : 1-type clay minerals was found in two soils. The mineral composition of the clay fraction in the TRE soils was hardly influenced by the difference of the meteorological factor or their water condition in this region, and this factor should not control the influence of parent materials derived from basic rocks. The TRE soils were developed under the condition of laterite genesis, and were regarded claymineralogically as a kind of the lateritic soils.     

Extractable heavy metals in Atlantic coast soils

Abstract

The analysis of soils, using 0.1 N HC1 as an extractant for the heavy metals, Cd, Cr, Ni and Pb on “fine”; textured North Shore and “coarse”; textured Annapolis Valley soils was completed. Results show ranges of 0.012 to 0.469 parts per million Cd; 0.102 to 2.90 parts per million Cr; 0.16 to 29.25 parts per million Ni and 0.12 to 244.8 parts per million Pb. Correlation studies indicate that the heavy metal content of fine textured soils is less influenced by changes in clay content and organic matter than are coarse textured soils. Generally the surface layers (0–15 cms) are higher in extractable heavy metal content than the lower layers (15–30 cms).     

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.     

The formation of duplex soils on hillslopes in the Sydney Basin,Australia

Field studies of Duplex soils (Red and Yellow Podzolics or Ultisols) on hillslopes in the Sydney Basin show that their primary morphological feature (the texture contrast between A and B horizons) is explicable in terms of differential bedrock alteration combined with downslope movement of the coarser grained materials as a discrete surface layer. The more usually invoked processes of clay illuviation and/or clay destruction are of no more than minor importance in the genesis of Duplex soils in this area.     

NH4F-extrahierbares P in Pelosolen und Basalt-Braunerden

NH₄-F extractable P in Pelosols and Cambisols The percentage of “Al-P” of the extractable inorganic P (∑“Al”-+“Fe”-+“Ca-P”, following the Chang and Jackson method) was assumed to be higher at the same pH in soils from basaltic parent material (as a result of an early Al supply from tektosilicates and slow clay formation) than in soils from clay-stone parent material. Contrary to this assumption, the percentage was (with one exception) not higher, probably because of an “Antivariscite-effect” by the 2:1 (clay) minerals.     

Application of the “standard cell” concept in research on soil formation

The concept of the “standard cell” of a rock, which compares numbers of cations associated with 160 oxygen ions (Barth, 1948) can be applied to the solid material of soils and saprolites as a means of tracing changes in element content at different depths in soil profiles weathered from igneous rocks. The “standard cells” can be derived readily from total silicate analyses of rock and soil materials and can be expressed as chemical formulae or in tables to facilitate comparisons. Standard cells for several layers from each of three profiles from southeast Queensland illustrate the type of information obtained. Standard cells of solum and weathered rock layers of a profile previously studied by mineralogical techniques permit a comparison of inferences about weathering which have been drawn by the two approaches.     

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.     

Morphology and properties of the soils of permafrost peatlands in the southeast of the Bol’shezemel’skaya tundra

The morphology and properties of the soils of permafrost peatlands in the southeast of the Bol’shezemel’skaya tundra are characterized. The soils developing in the areas of barren peat circles differ from oligotrophic permafrost-affected peat soils (Cryic Histosols) of vegetated peat mounds in a number of morphological and physicochemical parameters. The soils of barren circles are characterized by the wellstructured surface horizons, relatively low exchangeable acidity, and higher rates of decomposition and humification of organic matter. It is shown that the development of barren peat circles on tops of peat mounds is favored by the activation of erosional and cryogenic processes in the topsoil. The role of winter wind erosion in the destruction of the upper peat and litter horizons is demonstrated. A comparative analysis of the temperature regime of soils of vegetated peat mounds and barren peat circles is presented. The soil–geocryological complex of peat mounds is a system consisting of three major layers: seasonally thawing layer–upper permafrost–underlying permafrost. The upper permafrost horizons of peat mounds at the depth of 50–90 cm are morphologically similar to the underlying permafrost. However, these layers differ in their physicochemical properties, especially in the composition and properties of their organic matter.     

Properties and regimes of vertisols with gilgai microtopography (a review)

Data on the morphology and spatial distribution of slickensides and cracks, particle-size distribution, the organic carbon content, the content and forms of carbonate concentrations, and physical and physicochemical properties of Vertisols with the gilgai microtopography are systematized. Relatively scarce information on the functioning regimes of gilgai soil complexes (their temperature and moisture conditions, redox potential, vertical and horizontal deformations, and soil density changes) is discussed. Common properties of gilgai soils are the clayey texture of their profiles and the high portion of smectitic minerals specifying the high shrink–swell capacity of the soil material. The most important specificity of soils with the gilgai microtopography is a significant horizontal differentiation of the soil profiles with alternation of bowl-shaped morphostructures with a thick dark layer without carbonates in microlows and diapiric morphostructures composed of the rising material of the lower layers with diverse carbonate concentrations on microhighs. Data on the spatial distribution of soil properties within the gilgai microcatenas can be applied in the studies of the genesis and evolution stages of the gilgai soil complexes.     

A hardpan podzol at Yarner Wood, Devon

Podzols under sessile oak at Yarner Wood National Nature Reserve have extraordinarily hard and compact grey subsurface (Ea) horizons. The parent material is solifluxion debris from sandstones and siltstones of the Culm Measures (Lower Carboniferous) into which small amounts of loess have been incorporated. The general morphological, micro-morphological and chemical features of these soils, which are classified as hardpan stagnopodzols, are outlined and compared with those of adjoining brown podzolic soils. The evidence shows that the compaction is due only to close packing of particles and not to cementation. The genesis of the hardpan stagnopodzols and their relationship to other hardpan soils elsewhere in the world is discussed and the creation of a'Densi-'Great Group within Soil Taxonomy is proposed.     

Nitrogen fertility and humic matter of chilean andosols

The principal volcanic ash soils of Chile is evidently the “trumao” soil that covers the Central Valley from an area north of Chillan (36°30′S) to Puerto Montt (4l03l′S), and which is very similar to Japanese Andosols in its morphological, chemical and physical properties (19, 20). The different conides of Antuco, Chillan, Villarrica, Llaima, Osorno, and others in this part of the Cordillera indicate that the parent materials of the soils could have various origins, not only horizontally but also vertically. Moreover, glaciations have further complicated the composition of the parent materials of the soils (Langohr, R., personal communication). Even earthquakes have influences on the soils in some districts (21). Irrespective of the origin of soil parent materials, certain trends appear to exist in some chemical and physical properties of the soils from north to south (18), suggesting a difference in fertility and organic matter.     

Morphologic evidence of lamellae forming directly from thin,clayey bedding planes in a dune

An excavation in a sand dune in southern Michigan revealed numerous, thin (<3 mm) clay-enriched strata between otherwise weakly stratified, clean, fine sand deposits. The parallelism of both the sandy and clayey strata suggest that they have direct geologic origins, having been deposited during formation of the dune. Although the clay-enriched strata and the intervening sandy layers are both within the sand textural class, the former contained between 3.0% and 5.4% clay, and the latter <1.8% clay. In areas of preferred leaching, such as below vertical root traces, the clayey strata thin out and become absent, or “bend downward”, become wavy and contorted, and take on the appearance of typical pedogenic lamellae. These observations support a theory of lamellae genesis that is both pedogenic and geogenic. Thin sedimentary strata may be pedogenically “transformed” into features that would normally be described as (entirely pedogenic) lamellae. Thus, many thin lamellae in Pleistocene-aged soils may simply be deformed and pedogenically altered sedimentary strata. This conclusion has implications for the nature and cyclicity of clay deposition in environments where thin lamellae are common in sandy soils.     

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.