Kinds Of Parent Materials Research Articles

Loess in Italy: Genesis, characteristics and occurrence

There is currently a renewed interest in loess genesis and occurrence in Italy. Well-known loess profiles in northern Italy have been re-examined, and previously unknown loess deposits in central and southern Italy have been reported. This work combines a meta-analysis of published data with new data, presented here for the first time, to provide the state of the art on the spatial distribution, characteristics, genesis, and deposition ages of loess in Italy. A database of 98 soil horizons from 91 soil profiles was created and made available. It stores information on soils formed from loess or containing layers that show admixture of loess. Soil data include the source of information, the topographic, geomorphological and geological setting, kind of parent material and land use, main soil horizon properties as described in the field, soil classification, particle size distribution and chemical data.Loess is reported from almost all regions of Italy. It is generally pedogenized throughout the entire loess body and forms the parent material of deep and complex soil profiles. The thickness of the loess deposits varies from a few decimeters to a few meters; pedogenesis and local reworking partially change the original loess characteristics. In this study, we propose a set of parameters that help recognizing loess in soils: particle size distribution and sorting, geomorphological setting, pedostratigraphic position, shape of the grains under optical and scanning electron microscope (SEM), and soil-micromorphological characteristics.The ages of the loess deposits range between 70 ka BP and 18 ka BP. There are also a number of samples that have been dated to the Holocene. The meta-analysis suggests that climate is not the only driver of loess deposition in Italy; geomorphological instability and human disturbance, as well as the influence of Saharan dust, most likely played major roles, too.This study demonstrates that loess is much more widespread in Italy than previously estimated. Yet, further research on the spatial and temporal distribution of loess deposition across the Mediterranean region is needed to better understand its genesis, sources and trajectories, periods of enhanced loess formation, and the role of loess deposits in ecosystem functioning and resilience.

A HIERARCHICAL SYSTEM OF SOIL GEOGRAPHIC ENTITIES CLASSIFICATION BASED ON SOIL CRITERIA

This system of soiI geographic entities classification (or of classification of regionalization units) is based on the concept that all the landscapes for soilscapes) units (or physiographic units/ irrespective of the ir size and heterogeneity, al the Earth surface. are the result of the combined actions both of cosmic (exogenous) and earthly(endogenous) factors. For the systematization of these geographic (physiographic) entities. the following hierarchical categories are proposed: thermal zone, hydrothermal subzone and domain as highest categories (resulted from exogenous factors influence); soil (macro, mezo, micro) regions (level, sloping, steep) as intermediate categories (resulted from geological-geomorphic factors influence superposed over the preceding one): elementary soilscape (pediom), combination (pedosociation) and pedounit (polypedon) as lowest categories (resulted from the influence of environmental conditions in a relatively homogenous small geological-geomorphic unit (area), locally modified by the position in the landform and kind of parent material. The criteria employed for defining these hierarchical categories are based on proper features. The thermal zones are defined by temperature regime class according to the U.S. Soil Taxonomy and intensity of solar radiation, and hydrothermal subzones by the annual pedorhythms with the ir periods of interruption or slowing down due to freezing or drying during the year. Soil regions are defined by quantitative parameters of the major forms of relief that represent also quantitative parametres of cover (influencing water and substance circulation, soil-regimes. microclimate, vegetation). The other categories are defined also by proper properties. For each category, correlations with climatic and geomorphic factors are presented. The introduction of the temperature and moisture regimes as criteria for geographic entities grouping (classification) could solve the problem of the implementation of) soil climate parametres in classification (taxonomy).

Geochemistry and biogeochemistry of rare earth elements in a surface environment (soil and plant) in South China

Plants and soils derived from different kinds of parent materials in South China were collected for analyses of rare earth elements (REEs) by inductively coupled plasma-mass spectrometry (ICP-MS). The distribution patterns and transportation characteristics of REEs in the soil–plant system were studied. The results show that geochemical characteristics of REEs depend on the types of soils, soils derived from granite being the highest in REE concentration. In a soil profile, REE concentrations are higher in B and C horizons than those in A horizon, with Eu negative anomaly and Ce positive anomaly. Plants of different genera growing in the same sampling site have quite similar REE distribution pattern, but plants of the same genera growing in different soils show considerable variation in characteristics of REEs. The patterns of the different parts of plant resemble each other, but the slope of the patterns becomes different. REEs have fractionated when they were transported and migrated from soil to plant root, stem and leaf, revealing that heavy REEs are relatively less available. REEs distributions in plants are influenced by the soil they grow in and also characterized by their individual biogeochemical characteristics. Biological absorption coefficients indicate difference of REE absorption capacity of plants.

Total concentrations and bioavailability of rare-earth elements in latesol in Hainan Province, China

Total and bioavailable concentrations of rare earth elements (REEs) in the latesol of Hainan Province, China, were measured by ICP-MS, and the distribution characteristics of REEs were discussed in various latesol profiles. The results show that the total concentrations of REEs were higher than the average statistical data of the whole China. The correlation coefficients between the total and bioavailable concentrations of REEs were from 0.66 to 0.95 (P<0,001, n=63). This suggests that it is necessary to study the bioavailable and total heavy metal concentrations in soils in order to assess the ecological and environmental effects, and to provide scientific information on REEs application as micro-elemental fertilizers, and consequently their potential health risks. The percentage of the bioavailable concentrations in the latesol derived from some kinds of parent materials was up to 50%, indicating that it was unnecessary to apply REE micro-elemental fertilizers in the soils. The application of REE micro-elemental fertilizers should be based on specific kinds of soils in order to maintain the agro-ecosystem and protect soil resources.

Classification of anthrosols with vitric/andic properties derived from lignite ash

To test the applicability of the Soil Reference Base of Soil Resources (ISSS/ISRIC/FAO, 1998. World Reference Base for Soil Resources, World Soil Resources Report 84, FAO, Rome) for soils derived from anthropogenic substrates, soils developed on lignite ashes in Germany which have some similarities with andosols were compared with natural volcanic soils from different countries. Soil parameters used for comparison were bulk density, clay content, Al o+0.5 Fe o, and P-retention, as they serve as diagnostic criteria to define either vitric or andic horizons. For Al o+0.5 Fe o, and P-retention, there was no statistically significant difference between both soil groups, the bulk densities of the lignite ash-derived soils were even significantly lower than those of the natural volcanic soils. Moreover, pH, total organic carbon, cation exchange capacity as well as the contents of carbonates and gypsum were collated and differences emerged between both soil groups concerning the contents of carbonates, gypsum and total organic carbon. In case of the lignite ash-derived soils, these parameters as well as the contents of oxalate soluble oxides were strongly influenced by the composition of the anthropogenic parent material. Up to now, such soil materials are not included as soil-forming materials in the World Reference Base for Soil Resources. We therefore suggested the introduction of a new diagnostic soil material, the so-called technogenic soil material into the anthropogeomorphic soil materials and to introduce “technogenic anthrosols” as a new reference subunit. In our proposition, technogenic materials are defined as anthropogeomorphic materials which are formed by technical processes including a distinct degree of transformation and/or new formation of soil-forming materials. Soil materials are categorised as “technogenic” when they consist of more than 70% (by volume) of soil material derived from technical processes like, e.g. combustion products of fossil energy sources, sewage sludges, blast furnace slags, etc. To include as much information as possible into the name of a soil, we developed a concept of reference soil series for the WRB combining pedogenetic and lithogenic information. Within this concept, these soils should be considered to be a subunit of anthrosols (vitri- or andi-technogenic anthrosols) and the specific properties of the soil-forming material (coaly, calcaric, gypsiric) should be given as additional information as Reference Soil Series as well as texture and kind of parent material.

Areias quartzosas da bacia do Ribeirão do Lobo (Brotas-Itirapina, SP) II: características mineralógicas e químicas

Aspectos mineralógicos e químicos foram estudados em três perfis de Areias Quartzosas localizados em uma toposequência da Bacia do Ribeirão do Lobo, nos municípios de Brotas e Itirapina, no Estado de São Paulo. A homogeneidade mineralógica observada entre os horizontes e entre os perfis permite que se conclua serem estes solos derivados do mesmo material de origem. A maturidade mineralógica e arredondamento dos grãos do resíduo pesado indicam que os solos estudados sofreram a mesma intensidade de transporte. Quimicamente são solos distróficos, caracterizados por reação ácida, baixos valores de soma de bases e elevada saturação com alumínio,determinando caráter álico.

Particle size and free iron oxide distribution in some latosols and groundwater laterites of Ghana

The distribution of particle size and Na-dithionite-extractable (di-Fe 2 O 3) and NH 4-oxalate-extractable (ox-Fe 2O 3) iron oxides were investigated in twelve soil profiles representing latosols and groundwater laterites. Soil profiles studied were selected from the major ecological zones of Ghana. The pattern of distribution of free Fe 2O 3 was closely related to that of clay (< 2 μ) in soil profiles of the humid forest zones where clay content was more than 40% in the B horizons. In soil profiles of the relatively dry savannah zones with less than 40% clay in the B horizon, the pattern of distribution of free Fe 2O 3 was closely related to that of silt (2–20 μ). The amount of free Fe 2O 3 in the soils appeared to be related to kind of parent rock or parent material and to climatic factors operating in the various ecological zones. Using the amount of di-Fe 2O 3 in the B horizon as a basis for assessing the relative degrees of pedogenesis in soil profiles developed from the same kind of parent material, it was concluded that soil profile development had progressed most in the rain forest zone. Free Fe 2O 3 was considered as having reached an advanced stage of crystallinity or aging in most of the soils because of the low ox-Fe 2O 3/di-Fe 2O 3 ratios in the solums of most of the soil profiles. Soils studied were placed in the ferrallitic and ferruginous soil classes of D'Hoore. The great soil groups could not be characterized by depth function curves of free Fe 2O 3. However, it was proposed that the relative amounts of di-Fe 2O 3 in the B horizons of the soil profiles could be used as a basis for classifying these soils at the family level.

Boron Adsorption Characteristics of Selected Amorphous Soils From Mexico and Hawaii

AbstractBoron adsorption by Mexican and Hawaiian soils derived from volcanic ash deposits as influenced by solution phase concentration, reaction time, suspension pH, temperature, percent amorphous Al2O3 and SiO2, and free Fe2O3 content was studied. The adsorption was satisfactorily described by the Langmuir adsorption equation. Adsorption maxima were considerably greater than those observed for soils derived from other kinds of parent materials. In the range from 10 to 40C increases in temperature affected boron adsorption slightly. Maximum adsorption occurred between pH 8 and 9, suggesting that these soils have a greater affinity for B(OH)‐4‐B than for B(OH)3‐B. Boron adsorption by both the Mexican and Hawaiian soils was significantly correlated with amorphous SiO2 plus Al2O3 and amorphous Al2O3. However, higher correlation coefficients were obtained between boron adsorption and percent amorphous Al2O3. No significant correlations were found between boron adsorption and amorphous SiO2, and free F2O3 content.

Soil Phosphorus in South Dakota: I. Inorganic Phosphorus Fractions of Some Soil Series

AbstractThe inorganic soil phosphorus of the upper three horizons of 16 profiles was fractionated. The soils were selected to provide for a comparison of four kinds of parent materials and two great soil groups.The data show that, in general, the four glacial parent materials had similar proportional amounts of the inorganic P fractions. Climate, as expressed through great soil group, did affect the proportional amounts of two of these fractions, however. Among Chernozem soils the Fe‐P fraction makes up a proportionally larger amount, and the Ca‐P fraction a proportionally smaller amount, than they each do in Chestnut soils. Neither parent material nor climate alters the proportional amount of Al‐P present in these soil series.

ON THE AGE OF THE EARLY PALEOLITHIC ARTIFACTS FOUND ON THE NYU UPLAND, ÔITA PREF., NORTHERN KYUSHU (PRELIMINARY REPORT)

About 50 stone implements (26 pebble tools, 17 flakes and 7 cores) have been found on the Nyu upland, east of Ôita City, northern Kyushu. They are quite similar to those of the Soan-culture of India, which runs through from the Mindel-Kiss interglacial to the Kiss glacial age. Nowhere were such implements ever seen in Japan. The culture characterized by such implements will be called “Nyuan-colture”. There are seven terraces in the Nyu upland, and the site is located on the second terrace of 60 to 90meters in height. The implements were gathered on the surface of the field, as a result of being dug ou by bull-dozers in the process of making an orchard garden, except one which was contained in the brecciaclay bed, the uppermost of the second terrace deposits. This clay is white or yellowish white and tuffaceous, and predominant in the upper part of the bed. The thickness of this clay layer is about 3 meters. It contains commonly angular and rounded gravels. The implement was found near the base of this clay layer. In the uppermost part of the clay layer a red soil has been developed. As a result of morphological investigation the authors recognized that this soil had been subjected to a kind of la erization. Some Japanese pedologists have considered the red soils of Japan are one of the zonal soils derid from various kinds of parent materials under the present bio-climatic conditions. But some others have opposed to this opinion, regarding those soils as paleosols judging from stratigraphical and geomorphological in-vestigations. The red soils with brilliant tone (10R-5YR) are widely distributed in northen Kyushu. The red soils as paleosols overlain by the welded tuff, which belongs to the Aso Volcano and one of the ejecta during the caldera forming period, or by the other type ejecta of the same origin, called the Y ene clay (tuffaceous clay), have been found in Yame-Kuroki district, south of Fukuoka City. In Japan if we attempt to find a time which the temperature was so high that red soils could be developed, and such warmer climate continued through the whole red soil forming period, it cannot be concim dered except an interglacial age. Therefore, it would be possible to say that the implements have passed at least one interglacial age.

The Relationship of Soils to Molybdenum Toxicity in Cattle in Nevada

AbstractThe relationship of soil factors associated with reported areas of Mo toxicity in cattle in seven agriculturally important valleys in Nevada was investigated. The level of Mo in the plant was selected as a measure of the soil factors, but Cu, Co, S and P were also determined in a large number of the forage samples.The Mo content varied both with plant species and soils. Under Nevada conditions, alfalfa contains about two‐thirds as much Mo as does the clover, and sedge about one‐sixth as much where the Mo content are very high. Grasses and sedges with high levels of Mo commonly have correspondingly low levels of Cu, Co, or P.The Mo levels were low in forage plants from the naturally well‐drained soils, and the levels of Cu, Co, S and P were considered to be adequate. Neither lithology nor physiography—alluvial fan or floodplain and terrace—is an important factor in well‐drained soils.Both high water table and surface organic accumulation, common soil characteristics of poorly drained soils, affect the Mo levels in the plant. The magnitude of their effect varies with kind of parent material. The exceedingly high (300 ppm.) Mo levels were found in forage from some granitic alluvial fans.The relationship of problem soil areas in Nevada to other Mo toxic areas is discussed.

The Agricultural Value of California Soils

N California in recent years work has been done toward the evaluating of soils in relation to their suitability for plant growth. Such work is naturally of geographic interest. The method adopted for rating the agricultural value of the soils is explained in some detail in two bulletins issued by the Agricultural Experiment Station at Berkeley.' The index used is defined as the numerical expression of the degree to which a particular soil presents conditions favorable for plant growth and crop production under good environmental conditions.2 Three general factors are considered: A, character of the soil profile; B, surface-soil texture; and C, modifying conditions, such as drainage and alkali. The ideal condition for each factor is 100 per cent. The rating is a multiple of the three figures allotted tothe three factors; hence a low figure for any one factor will influence the resultant rating. For example, Hanford fine sandy loam may be allotted 100 per cent for each of the three factors: the index rating would then be I00. On the other hand, presence of alkali may lead to the allotment of 25 per cent to factor C, and the index rating then becomes 25. All characteristics of soil profile are evaluated by factor A except surface texture. These characteristics are determined by kind of parent material, its mode of formation or accumulation, and the age or degree of modification of the soil material by the weathering agencies of climate, supplemented by vegetation and opposed by erosion and deposition. The agricultural soils of California are placed in six groups according to physical profile characteristics. (I) Unweathered or slightly weathered secondary soils, loose and friable, with a depth of six feet or more, have ratings of 95 to 100 per cent. (2) Deep, moderately weathered secondary soils, less permeable because of their compact subsoils, have ratings of 80 to 95 per cent. (3) Strongly weathered secondary soils with dense clay subsoils, developed on unconsolidated material, have ratings of 40 to 8o per cent. (4) Maturely weathered secondary soils with hardpan, usually with a dense overlying clay layer, have ratings of 5 to 60 per cent according to the depth to the cemented layer. (5) Strongly weathered soils with dense clay subsoils resting on a consolidated hardpan-like substratum have ratings of 20 to 40 per cent. (6) Primary soils underlain by bedrock and developed from it have ratings of 20 to 70 per cent according to the depth to the bedrock. These profile groups are associated with various conditions of surface relief: I, flat or gently sloping alluvial flood plains; 2 and 4, valley floors and benches or terraces which may be eroded to a varying degree, the surface of the fourth group perhaps characterized by hog wallows; 3, terraces or benches, perhaps somewhat eroded; 5, high eroded marine terraces on the coastal plain; 6, rolling, hilly, or mountainous topography. Factor B concerns surface-soil texture and thus covers consistency, porosity, permeability, and tilth or arability.3 The highest ratings, as we should expect, go to soils of medium texture, the lowest to soils of very heavy and very light texture and to those that are very gravelly or stony. Soils with much sand or gravel are relatively low in plant nutrients and do not retain moisture; on the other hand, many clays are difficult to handle, though they may contain maximum moisture and nutrients.