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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Models for the genesis of industrial minerals in mafic and ultramafic rocks

Power, Matthew R. January 1998 (has links)
No description available.
2

The Historical Production of Elemental Phosphorus in Pinellas County, Florida: An Environmental Assessment

Robinson, Stephen D. 08 May 2007 (has links)
This thesis was completed in order to assess and document the environmental effects that are the result of elemental phosphorus production in Pinellas County Florida. The study utilized a collection of information resources that included: personal interviews, technical references, historical documents, legal documents and field observations. By utilizing five different sources of information a broad understanding of the problem was developed. Pinellas County and Tarpon Springs officials were interested in creating a more diversified economy in the years following World War-II. The Victor Chemical Works Company responded to the interest in economic diversity by proposing to build an elemental phosphorus production facility in the area of greater Tarpon Springs, Florida. The elemental phosphorus production facility was completed and began operation in November of 1947. Three months after the facility commenced production local residents noticed damage to trees and painted surfaces on private properties. Seven months following commencement of elemental phosphorus production local residents filed suit against the Victor Chemical Works Company due to deleterious gasses and dust that appeared to be damaging to biologic health. The elemental phosphorus production facility operated from 1947 to 1981. The 34-year operational period exposed workers, residents and biologic communities to extended periods of elevated sulfur dioxide, phosphorus pentoxide gas, phosphine gas, fluorine, lead, radium-226 and asbestos. Utilizing personal interviews, technical document review, legal document review and field observations the thesis provided an amalgamation of diverse information upon which the conclusions were based. The research concludes that the production of elemental phosphorus exposed all physical and cultural environments of northwest Pinellas County to many complex adverse environmental impacts that continue to persist in 2007, approximately 26-years following the suspension of production.
3

Recrystallization of pedogenic and biogenic carbonates in soil: Environmental controls, modelling and relevance for paleoenvironmental reconstructions and dating

Zamanian, Kazem 12 May 2017 (has links)
No description available.
4

Carbon Sequestration via Concrete Weathering in Soil

Multer, Brittany 06 July 2023 (has links)
No description available.
5

Horizontes cimentados em Argissolos e Espodossolos dos tabuleiros costeiros e em Neossolos Regolíticos e Planossolos da depressão sertaneja no Nordeste do Brasil / Cemented Horizons in ultisol and spodosols from the coastal tablelands and in inceptisols and alfisols from the \"sertaneja\" depression of Northeast Brazil

Araújo Filho, José Coêlho de 06 February 2004 (has links)
Horizontes cimentados foram estudados em Argissolos Amarelos, Argissolos Acinzentados e Espodossolos dos tabuleiros costeiros e em Neossolos Regolíticos e Planossolos da depressão sertaneja, no Nordeste do Brasil. A ênfase dos estudos foi direcionada para os horizontes cimentados desenvolvidos em suaves depressões dos tabuleiros costeiros. O objetivo principal foi caracterizar a natureza de agentes cimentantes e de horizontes cimentados considerados como duripãs e fragipãs, e inferir processos pedogenéticos envolvidos na formação dos mesmos. Os horizontes cimentados foram caracterizados com base em aspectos morfológicos, físicos, químicos, mineralógicos e micromorfológicos. A caracterização e a dedução dos agentes cimentantes foram estabelecidas com base, principalmente, em extrações seletivas de fases amorfas pelos métodos do oxalato de amônio, Tiron e pirofosfato de sódio. O refinamento dos estudos foi desenvolvido com o apoio da microscopia eletrônica. Na região dos tabuleiros costeiros, os resultados indicaram que os agentes cimentantes principais são compostos aluminosos, identificados como aluminossilicatos amorfos hidratados e, secundariamente, complexos organometálicos. Foi constatado, também, altas proporções de ferro em compostos amorfos, em associação com complexos organometálicos, cimentando finas camadas ferruginosas (horizonte plácico). O balanço geoquímico de massa em geral foi indicativo do acúmulo de alumínio nos horizontes cimentados, constituídos essencialmente por caulinita e quartzo. Conforme características e atributos diagnósticos, os horizontes com cimentação fraca foram enquadrados como fragipã. Os que apresentaram cimentação forte, em função da natureza dos agentes cimentantes principais, foram enquadrados como horizonte dúrico, ortstein e horizonte plácico. Portanto, parece ser inadequado o uso tradicional do termo duripã para denominar horizontes com agentes cimentantes principais aluminosos, como os desenvolvidos nesta região. No ambiente das suaves depressões, os principais mecanismos envolvidos na formação desses horizontes foram a podzolização moderada, o transporte mecânico de argila e condições hidromórficas, ainda que temporárias. Na zona da depressão sertaneja, ao contrário, foi constatado que os agentes cimentantes principais são compostos silicosos, mas sempre acompanhados por alumínio. Os horizontes com cimentação forte desenvolvidos em Neossolos Regolíticos mostraram um conjunto de características que permitiram enquadrá-los como duripãs. O horizonte com cimentação fraca desenvolvido no perfil de Planossolo, com mais de 10 cm de espessura, foi classificado como fragipã. O balanço geoquímico de massa não indicou nenhum acúmulo de silício nos horizontes cimentados. A composição mineralógica essencial destes horizontes apresentou caulinita, quartzo, feldspato e pequenas proporções de argilominerais 2:1. As investigações indicaram que as proporções entre o conteúdo de frações finas e os teores de agentes cimentantes foram fatores determinantes na diferenciação entre horizontes com cimentação forte e fraca. Entretanto, tais proporções só puderam ser observadas com mais detalhes nos horizontes cimentados desenvolvidos nos solos dos tabuleiros costeiros. / The present study was carried out in cemented horizons in Ultisols and Spodosols from the coastal tablelands, and in Inceptisols and Alfisols from the sertaneja depression of Northeast Brazil. The emphasis was concentrated on the cemented horizons developed in smooth depressions in the coastal tablelands. The main objective was to identify the cementing agents and to characterize horizons considered to be duripan and fragipan, and to infer the pedogenic processes involved in their formation. The morphological, micromorphological, physical, chemical, and mineralogical features of the cemented horizons were described. The identification of the cementing agents was achieved with selective extractions of the amorphous phases using ammonium oxalate, Tiron and sodium pyrophosphate. Detailed studies were carried out with an electron microscope. In the coastal tablelands region, the results indicated that the principal cementing agents are aluminum compounds, found to be amorphous hydrated aluminosilicates, and secondarily, organo-metallic complexes. The significant contents of amorphous iron compounds associated with organo-metallic complexes were found to cement thin ferruginous layers (placic horizon). The overall geochemical mass balance indicated the accumulation of aluminum in the cemented horizons composed mainly of quartz and kaolinite. Weakly cemented horizons were classified as fragipans. The more strongly cemented horizons were separated into duric, ortstein and placic horizons, according to their principal cementing agents. The traditional use of the term duripan seems to be inappropriate in the case of horizons in which the principal cementing agents are aluminous, such as those occurring in this region. In the smooth depression domain, the main mechanisms of the formation of these horizons are moderate podzolization, clay translocation, and the development of hydromorphic conditions, although temporary. In contrast, the main cementing agents in the sertaneja depression region are silicon compounds, always accompanied by aluminum. Strongly cemented horizons developed in Inceptisols have the characteristics of duripan. The weakly cemented horizon thicker than 10 cm within an Alfisol profile was classified as fragipan. The geochemical mass balance showed no silica accumulation in the cemented horizons. The mineralogical composition of these horizons includes kaolinite, quartz, feldspar and small amounts of 2:1 clay minerals. The investigations indicated that the relative proportions of fine fractions and cementing agents were the main factors in determining the degree of cementation. However, it was only possible to study these proportions in more detail in the cemented horizons of the soils formed on the coastal tablelands.
6

Horizontes cimentados em Argissolos e Espodossolos dos tabuleiros costeiros e em Neossolos Regolíticos e Planossolos da depressão sertaneja no Nordeste do Brasil / Cemented Horizons in ultisol and spodosols from the coastal tablelands and in inceptisols and alfisols from the \"sertaneja\" depression of Northeast Brazil

José Coêlho de Araújo Filho 06 February 2004 (has links)
Horizontes cimentados foram estudados em Argissolos Amarelos, Argissolos Acinzentados e Espodossolos dos tabuleiros costeiros e em Neossolos Regolíticos e Planossolos da depressão sertaneja, no Nordeste do Brasil. A ênfase dos estudos foi direcionada para os horizontes cimentados desenvolvidos em suaves depressões dos tabuleiros costeiros. O objetivo principal foi caracterizar a natureza de agentes cimentantes e de horizontes cimentados considerados como duripãs e fragipãs, e inferir processos pedogenéticos envolvidos na formação dos mesmos. Os horizontes cimentados foram caracterizados com base em aspectos morfológicos, físicos, químicos, mineralógicos e micromorfológicos. A caracterização e a dedução dos agentes cimentantes foram estabelecidas com base, principalmente, em extrações seletivas de fases amorfas pelos métodos do oxalato de amônio, Tiron e pirofosfato de sódio. O refinamento dos estudos foi desenvolvido com o apoio da microscopia eletrônica. Na região dos tabuleiros costeiros, os resultados indicaram que os agentes cimentantes principais são compostos aluminosos, identificados como aluminossilicatos amorfos hidratados e, secundariamente, complexos organometálicos. Foi constatado, também, altas proporções de ferro em compostos amorfos, em associação com complexos organometálicos, cimentando finas camadas ferruginosas (horizonte plácico). O balanço geoquímico de massa em geral foi indicativo do acúmulo de alumínio nos horizontes cimentados, constituídos essencialmente por caulinita e quartzo. Conforme características e atributos diagnósticos, os horizontes com cimentação fraca foram enquadrados como fragipã. Os que apresentaram cimentação forte, em função da natureza dos agentes cimentantes principais, foram enquadrados como horizonte dúrico, ortstein e horizonte plácico. Portanto, parece ser inadequado o uso tradicional do termo duripã para denominar horizontes com agentes cimentantes principais aluminosos, como os desenvolvidos nesta região. No ambiente das suaves depressões, os principais mecanismos envolvidos na formação desses horizontes foram a podzolização moderada, o transporte mecânico de argila e condições hidromórficas, ainda que temporárias. Na zona da depressão sertaneja, ao contrário, foi constatado que os agentes cimentantes principais são compostos silicosos, mas sempre acompanhados por alumínio. Os horizontes com cimentação forte desenvolvidos em Neossolos Regolíticos mostraram um conjunto de características que permitiram enquadrá-los como duripãs. O horizonte com cimentação fraca desenvolvido no perfil de Planossolo, com mais de 10 cm de espessura, foi classificado como fragipã. O balanço geoquímico de massa não indicou nenhum acúmulo de silício nos horizontes cimentados. A composição mineralógica essencial destes horizontes apresentou caulinita, quartzo, feldspato e pequenas proporções de argilominerais 2:1. As investigações indicaram que as proporções entre o conteúdo de frações finas e os teores de agentes cimentantes foram fatores determinantes na diferenciação entre horizontes com cimentação forte e fraca. Entretanto, tais proporções só puderam ser observadas com mais detalhes nos horizontes cimentados desenvolvidos nos solos dos tabuleiros costeiros. / The present study was carried out in cemented horizons in Ultisols and Spodosols from the coastal tablelands, and in Inceptisols and Alfisols from the sertaneja depression of Northeast Brazil. The emphasis was concentrated on the cemented horizons developed in smooth depressions in the coastal tablelands. The main objective was to identify the cementing agents and to characterize horizons considered to be duripan and fragipan, and to infer the pedogenic processes involved in their formation. The morphological, micromorphological, physical, chemical, and mineralogical features of the cemented horizons were described. The identification of the cementing agents was achieved with selective extractions of the amorphous phases using ammonium oxalate, Tiron and sodium pyrophosphate. Detailed studies were carried out with an electron microscope. In the coastal tablelands region, the results indicated that the principal cementing agents are aluminum compounds, found to be amorphous hydrated aluminosilicates, and secondarily, organo-metallic complexes. The significant contents of amorphous iron compounds associated with organo-metallic complexes were found to cement thin ferruginous layers (placic horizon). The overall geochemical mass balance indicated the accumulation of aluminum in the cemented horizons composed mainly of quartz and kaolinite. Weakly cemented horizons were classified as fragipans. The more strongly cemented horizons were separated into duric, ortstein and placic horizons, according to their principal cementing agents. The traditional use of the term duripan seems to be inappropriate in the case of horizons in which the principal cementing agents are aluminous, such as those occurring in this region. In the smooth depression domain, the main mechanisms of the formation of these horizons are moderate podzolization, clay translocation, and the development of hydromorphic conditions, although temporary. In contrast, the main cementing agents in the sertaneja depression region are silicon compounds, always accompanied by aluminum. Strongly cemented horizons developed in Inceptisols have the characteristics of duripan. The weakly cemented horizon thicker than 10 cm within an Alfisol profile was classified as fragipan. The geochemical mass balance showed no silica accumulation in the cemented horizons. The mineralogical composition of these horizons includes kaolinite, quartz, feldspar and small amounts of 2:1 clay minerals. The investigations indicated that the relative proportions of fine fractions and cementing agents were the main factors in determining the degree of cementation. However, it was only possible to study these proportions in more detail in the cemented horizons of the soils formed on the coastal tablelands.
7

Gênese e levantamento de solos da Serra de Santana no Seridó Potiguar

Farias, Phamella Kalliny Pereira 22 February 2016 (has links)
Submitted by Socorro Pontes (socorrop@ufersa.edu.br) on 2016-11-17T15:53:38Z No. of bitstreams: 1 PhâmellaKPF_DISSERT.pdf: 2697111 bytes, checksum: 6489ccb9ad9ef120c49053934aaa3387 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-03-21T14:37:44Z (GMT) No. of bitstreams: 1 PhâmellaKPF_DISSERT.pdf: 2697111 bytes, checksum: 6489ccb9ad9ef120c49053934aaa3387 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-03-21T15:04:17Z (GMT) No. of bitstreams: 1 PhâmellaKPF_DISSERT.pdf: 2697111 bytes, checksum: 6489ccb9ad9ef120c49053934aaa3387 (MD5) / Made available in DSpace on 2017-03-21T15:05:51Z (GMT). No. of bitstreams: 1 PhâmellaKPF_DISSERT.pdf: 2697111 bytes, checksum: 6489ccb9ad9ef120c49053934aaa3387 (MD5) Previous issue date: 2016-02-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In understanding a more appropriate management, the soil survey in a region it has a fundamental importance. Thus, a constant updating of the soil classes is necessary for the various agricultural uses are analyzed and established the most appropriate way possible. The Rio Grande do Norte has hills formations that differ from the soil and climatic conditions prevailing in the state, with deeper soils and acidic and milder weather. Among these formations, there is the Santana’s Hill, which is embedded in the Martins Formation with deposits settled in disagreement over the lens and inserted basis in the Potiguar Seridó region, with important agricultural use for the region, with mainly cashew cultivation and cassava. With this, the objective of this study was to understand the genesis of representative soils of the Santana’s Hill and draw up an exploratory soil map of the region. Morphological, physical, chemical and mineralogical analyzes of representative profiles were performed that make up the Santana’s Hill. Representative profiles were classified as Typic Haplustox; Xanthic Eutrustox; Typic Eutrustox; Ustic Quartzipsamments; Lithic Ustorthents; Typic Ustipsamments and Dystric Haplustepts. By observing morphological attributes it was noticed that there was a great influence of the parent material factor in distinguishing the main soil types found in the study area, since the topography and climatic conditions are similar throughout the territorial extension. The textural class of the profiles studied ranged from sandy to sandy-clay-sandy due to high existing levels in sand horizons, identifying minerals that were more resistant to weathering process and the strong link with the material of sedimentary origin. All profiles showed acid reaction, wide range of base saturation between profiles and low values of electrical conductivity. The mineralogical composition of the clay fraction of the profiles were similar, with clay type Illite/Mica, Kaolinite and Goethite, and Quartz peaks. The use of GIS allows updating existing soil classes in the Santana’s Hill, as well as updating the percentage of occupation of each soil type / Na compreensão de um manejo mais adequado, o levantamento do tipo de solo em uma região possui uma importância fundamental. Desse modo, uma atualização constante das classes de solos se faz necessária para que os diversos usos agrícolas sejam analisados e estabelecidos da forma mais adequada possível. O Rio Grande do Norte possui formações serranas que diferem das condições edafoclimáticas predominantes no estado, apresentando solos mais profundos e ácidos e clima mais ameno. Dentre estas formações, destaca-se a Serra de Santana, que está inserida na Formação dos Martins com depósitos assentados em discordância sobre o embasamento cristalino e inserida na região do Seridó Potiguar, apresentando importante uso agrícola para a região, com o cultivo principalmente de caju e mandioca. Com isto, objetivou-se neste trabalho compreender a gênese dos solos representativos da Serra de Santana e elaborar um mapa de solos exploratório da região. Foram realizadas análises morfológicas, físicas, químicas e mineralógicas de perfis representativos que compõem a Serra de Santana. Os perfis representativos foram classificados como: LATOSSOLO AMARELO Distrófico argissólico; LATOSSOLO AMARELO Eutrófico argissólico; NEOSSOLO QUARTZARÊNICO Órtico típico; NEOSSOLO LITÓLICO Eutrófico fragmentário; NEOSSOLO REGOLÍTICO Eutrófico típico e CAMBISSOLO HÁPLICO Tb Eutrófico léptico. Ao observar os atributos morfológicos percebeu-se que houve grande influência do fator material de origem na distinção das principais classes de solo encontradas na área de estudo, já que o relevo e condição climática são similares ao longo de toda extensão territorial. A classe textural dos perfis estudados variou de areia a franco-argilo-arenosa devido aos altos teores de areia existentes nos horizontes, identificando minerais que foram mais resistentes ao processo de intemperismo e a forte ligação com o material de origem sedimentar. Todos os perfis apresentaram reação ácida, grande variação de saturação por bases entre os perfis e baixos valores de condutividade elétrica. A composição mineralógica da fração argila dos perfis foi similar, apresentando argilominerais do tipo Ilita/Mica, Caulinita e Goethita, além de picos de Quartzo. O uso do geoprocessamento permitiu atualização das classes de solo existentes na Serra de Santana, bem como a atualização da percentagem de ocupação de cada classe de solo / 2016-11-17
8

Biogeochemistry of Carbon on Disturbed Forest Landscapes

Amichev, Beyhan Y. 11 May 2007 (has links)
Carbon accreditation of forest development projects is essential for sequestering atmospheric CO2 under the provisions of the Kyoto Protocol. The carbon sequestration potential of surface coal-mined lands is not well known. The purpose of this work was to determine how to measure carbon sequestration and estimate the additional amount that could be sequestered using different reforestation methods compared to the common practice of establishing grasslands. I developed a thermal oxidation technique for differentiating sequestered soil carbon from inorganic and fossilized carbon found at high levels in mine soils along with a geospatial and statistical protocol for carbon monitoring and accounting. I used existing tree, litter, and soil carbon data for 14 mined and 8 adjacent, non-mined forests in the Midwestern and Eastern coal regions to determine, and model sequestered carbon across the spectrum of site index and stand age in pine, mixed, and hardwood forest stands. Finally, I developed the framework of a decision support system consisting of the first iteration of a dynamic model to predict carbon sequestration for a 60-year period for three forest types (white pine, hybrid poplar, and native hardwoods) at three levels of management intensity: low (weed control), medium (weed control and tillage) and high (weed control, tillage, and fertilization). On average, the highest amount of ecosystem carbon on mined land was sequestered by pine stands (148 Mg ha-1), followed by hardwood (130 Mg ha-1) and mixed stands (118 Mg ha-1). Non-mined hardwood stands contained 210 Mg C ha-1, which was about 62% higher than the average of all mined stands. After 60 years, the net carbon in ecosystem components, wood products, and landfills ranged from 20 to 235 Mg ha-1 among all scenarios. The highest net amount of carbon was estimated under mixed hardwood vegetation established by the highest intensity treatment. Under this scenario, a surface-mined land of average site quality would sequester net carbon stock at 235 Mg C ha-1, at a rate of 3.9 Mg C ha-1 yr-1, which was 100% greater than a grassland scenario. Reforestation is a logical choice for mined land reclamation if carbon sequestration is a management objective. / Ph. D.
9

Spatial Trends and Facies Distribution of the High-Energy Alluvial Cutler Formation, Southeastern Utah

Allred, Isaac John 01 June 2016 (has links)
The Cutler Formation is composed of thick, arkosic, alluvial conglomerate, sandstone, and mudstone shed southwestward from the Uncompahgre Uplift into the Paradox Basin. More basin-ward the Cutler is recognized as a group consisting of differentiable formations. Discrete formations historically have not been distinguished near the uplift, but this study identified several separate successions in the Richardson Amphitheater. Research at the Richardson Amphitheater, ~12 km southwest of the uplift and ~30 km northeast of Moab, Utah, led to a systematic subdivision of the Permian Cutler Formation proximal to the uplift. Likely driven by channel cutting and migration across the alluvial fan, six 10-20 m thick successions are partially exposed. The dominant observed facies are basal conglomerate and channel-fill trough cross-stratified sandstone overlain by finer-grained distal sheetflood and frequently pedogenically altered sandstone. Down-warping of identified successions and the presence of additional sands within the area of flexure suggest that localized salt withdrawal created a sediment depocenter in the Richardson Amphitheater, ~6 km northwest of the Onion Creek salt diapir. The identified salt withdrawal feature is more proximal to the Uncompahgre Uplift than any of the major documented salt structures in the area and was not previously documented. Six measured stratigraphic sections and hundreds of high-precision differential GPS data points outlining major lateral erosional surfaces form the basis for interpretation. Five mapped erosional surfaces (bounding surfaces based upon differential GPS point interpolation) are laterally extensive within the approximately one square kilometer study area, and as such, represent stratigraphically significant surfaces. Within the generated structural geocellular model, stratigraphic data from measured sections informed facies modeling between major surfaces. This outcrop model may serve as an analogue for subsurface systems deposited in similar settings.
10

Eigenschaften und Genese periglazialer Deckschichten auf Carbonatgesteinen des Muschelkalks in einem Teilgebiet der ostthüringischen Triaslandschaft / Genesis and properties of periglacial slope deposits on calcareous rocks of the Muschelkalk formation in an area of the eastern Thuringian Triassic landscape.

Bullmann, Heike 02 May 2011 (has links) (PDF)
Periglaziale Deckschichten auf carbonatreichen Gesteinen der geologischen Formation des Muschelkalks sind bisher nur peripher Gegenstand wissenschaftlicher Untersuchungen innerhalb der Deckschichtenfor-schung. Um diese Lücke zu schließen, widmet sich die vorliegende Arbeit dem Aufbau des oberflächenna-hen Untergrundes im Muschelkalk in einem Teilgebiet in der ostthüringischen Triaslandschaft. Die Ergebnisse zeigen, dass die periglazialen Deckschichten in Abhängigkeit von lithologischen Gesteins-merkmalen und Relieffaktoren (Exposition, Neigung) eine hohe räumliche Heterogenität hinsichtlich der stoff-lichen Zusammensetzung, der vertikalen Gliederung und Gründigkeit aufweisen. Sie sind in Basislagen (LB), Mittellagen (LM) und Hauptlagen (LH) gegliedert, die ihrerseits eigenständige Schichten beinhalten können. Die Lagenbildungen über carbonatreichen Gesteinen des Muschelkalks weisen Besonderheiten im Aufbau, in den stofflichen Eigenschaften und in ihrer Genese auf. Die Basislagen sind in der Regel mehrgliedrig entwickelt und können bis zu drei, faziell zu unterscheidende Substratkomplexe enthalten. Dies sind i) eine skelettfreie Kalksteinbraunlehm-Fließerde (LB-F), ii) ein Kalk-steinbraunlehmschutt (LB-1) und iii) ein Kalksteinschutt (LB-2). Die Zweiteilung der Basislagenschutte sowie die Abfolge LB-1/ LB-2 (LB-1 über LB-2) können als charakteristische Merkmale der Basislagenbildung über Muschelkalk herausgestellt werden. Skelettfreie Kalksteinbraunlehme (LB-F) stellen eine Besonderheit auf Carbonatgesteinen dar, da vergleichbare Bildungen auf quarz- und silikatreichen Standorten fehlen. Die Hauptlagen werden in eine schluffreiche (LH) und tonreiche (LHT) Fazies unterschieden. Beide zeichnen sich durch eine vollständige Skelettfreiheit aus, die ebenfalls als übergreifendes Merkmal über Muschelkalk gelten kann. Zwei Mittellagentypen sind mit skelettfreier Mittellage (LM) und skeletthaltiger Mittellage (LMs) vertreten. Die Genese der Basislagenabfolge LB-F/ LB-1/ LB-2 fand vollständig im Weichselglazial statt und schließt eine periglaziale Genese der Kalksteinbraunlehme ein. Die Beteiligung von Spülprozessen an der (Geli-) Solifluktion hat die Akkumulation von Lösungsrückständen (= Kalksteinbraunlehm) gefördert. Die Zweiteilung der Basisschutte kann ebenfalls durch die Mitwirkung ablualer Prozesse erklärt werden. Die Kalksteinbraun-lehm-Fließerde entstand synsedimentär zur Bildung der Basislagenschutte durch laterale Ausspülung. Die Variabilität der Lössedimente wird neben Luv-/Lee-Effekten und präsedimentäre karstartige Hohlformen vor allem auch über eine differenzierte periglaziale Bodenfeuchte- und Vegetationsverteilung gesteuert. In der Arbeit wurden u.a. der gU/fU-Quotient, pedogene Eisenoxide (Feo, Fed), Gesamteisengehalt (Fet), Fet/Ton-Quotient und (Fed-Feo/(Fet/Ton)-Quotient (nach GÜNSTER et al. 2001) sowie die Korrelation von Tongehalt und pedogenem Eisen für alle oben genannten Substrate ermittelt. Eine integrative Betrachtung dieser Parameter ist grundsätzlich geeignet, primäre Sedimenteigenschaften der Substrate herauszustellen und eine pedogenetische Überprägung abzugrenzen. Darüber hinaus erlauben sie Aussagen zur Genese. Der Tongehalt der Mittellagen konnte neben der Überformung durch Tonverlagerung als sedimentogene Ei-genschaft belegt werden. Kalksteinbraunlehme mit weniger als 65% Tongehalt müssen nicht grundsätzlich lösslehmbeeinflusst sein. Rezente Lösungsprozesse und eine rezente Weiterbildung der Kalksteinbraunleh-me konnten auch im Liegenden mächtigerer Lösssedimente nachgewiesen werden. Es wird gezeigt, wie die periglazialen Decksedimente in ihrer räumlichen, vertikalen und stofflichen Variabilität Einfluss auf die Heterogenität der Bodendecke nehmen.

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