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Lynn M Riddiford - One of the best experts on this subject based on the ideXlab platform.
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Dev Genes Evol (2000) 210:358–372 © Springer-Verlag 2000 ORIGINAL ARTICLE
2013Co-Authors: Jason Hodin, Lynn M RiddifordAbstract:Parallel alterations in the timing of ovarian Ecdysone Receptor and Ultraspiracle expression characterize the independent evolution of larval reproduction in two species of gall midges (Diptera: Cecidomyiidae) Received: 30 July 1999 / Accepted: 23 Feburary 2000 Abstract Although most insects reproduce in the adult stage, facultative larval or pupal reproduction (Paedogenesis) has evolved at least six times indepently in insects, twice in gall midges of the family Cecidomyiidae (Diptera). Paedogenesis in gall midges involves the precocious growth and differentiation of the ovary in an otherwise larval form. We have previously shown that the timing of expression of the Ecdysone Receptor (EcR) and Ultraspiracle (USP), the two proteins that constitute the functional receptor for the steroid hormone 20-hydroxyecdysone, regulates the timing and progression of ovarian differentiation in Drosophila melanogaster (Diptera: Drosophilidae). Here we test the hypothesis that precocious activation of EcR and USP in the ovaries of paedogenetic gall midges allows for precocious ovarian differentiation. Using monoclonal antibodies directed against insect EcR and USP proteins, we first show that when these gall midges are reared under conditions that promote typical, metamorphic development, upregulation of EcR and USP occurs in the final larval stage. By contrast, in the paedogenetic life cycle, EcR and USP are up-regulated early in the first larval stage. A similar pattern is seen for two independently-evolved paedogenetic gall midges, Heteropeza pygmaea and Mycophila speyeri. We discuss our results in the context of developmental constraints on the evolution of Paedogenesis in dipteran insects
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parallel alterations in the timing of ovarian ecdysone receptor and ultraspiracle expression characterize the independent evolution of larval reproduction in two species of gall midges diptera cecidomyiidae
Development Genes and Evolution, 2000Co-Authors: Jason Hodin, Lynn M RiddifordAbstract:Although most insects reproduce in the adult stage, facultative larval or pupal reproduction (Paedogenesis) has evolved at least six times indepently in insects, twice in gall midges of the family Cecidomyiidae (Diptera). Paedogenesis in gall midges involves the precocious growth and differentiation of the ovary in an otherwise larval form. We have previously shown that the timing of expression of the Ecdysone Receptor (EcR) and Ultraspiracle (USP), the two proteins that constitute the functional receptor for the steroid hormone 20-hydroxyecdysone, regulates the timing and progression of ovarian differentiation in Drosophila melanogaster (Diptera: Drosophilidae). Here we test the hypothesis that precocious activation of EcR and USP in the ovaries of paedogenetic gall midges allows for precocious ovarian differentiation. Using monoclonal antibodies directed against insect EcR and USP proteins, we first show that when these gall midges are reared under conditions that promote typical, metamorphic development, up- regulation of EcR and USP occurs in the final larval stage. By contrast, in the paedogenetic life cycle, EcR and USP are up-regulated early in the first larval stage. A similar pattern is seen for two independently-evolved paedogenetic gall midges, Heteropeza pygmaea and Mycophila speyeri. We discuss our results in the context of developmental constraints on the evolution of Paedogenesis in dipteran insects.
Jean-louis Morel - One of the best experts on this subject based on the ideXlab platform.
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Technosol construction with by-products and wastes: pedogenesis and modelling
2016Co-Authors: Sophie Leguedois, Geoffroy Séré, Françoise Watteau, Christophe Schwartz, Apolline Auclerc, Audrey Boigné, Fabrice Bureau, Estelle Langlois, Jean-louis MorelAbstract:Technosol construction with by-products and wastes: pedogenesis and modelling. SUMMER SCHOOL ON CONTAMINATED SEDIMENTS: CHARACTERIZATION AND REMEDIATION
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Modelling pedogenesis of technosols
Geoderma, 2016Co-Authors: Sophie Leguedois, Geoffroy Séré, Jérôme Cortet, Stéphanie Ouvrard, Françoise Watteau, Christophe Schwartz, Hermine Huot, Apolline Auclerc, Jean-louis MorelAbstract:Technosols, soils subjected to a strong human influence and containing significant amounts of artefacts, are characteristic of the Anthropocene. In order to better apprehend their growing importance in our current environment, our knowledge of the evolution and fate of these soils must be improved. The aim of this article is to promote pedogenic modelling for Technosols by proposing an appropriate framework. The paper first defines the characteristics of Technosol pedogenesis, and then considers the requirements for its modelling in light of general concepts of pedogenesis, modelling tools and techniques, and 18 selected existing quantitative models. This mixed technical and conceptual analysis allows us to address at once the modelling approach, the choice of processes, the integration of control variables, the time scales, the spatial representation, and the data needed for such a framework. Technosol pedogenesis is characterised by the soils' anthropic creation, a young age, a climate globally favourable for soil evolution, a surprising level of biological activity, and mostly reactive artefacts as parent materials. Pedogenic processes observed in Technosols are similar to those occurring in more natural soils; however, they generally have fast kinetics and occur in unusual assemblages. We propose that the modelling framework for Technosol evolution should be based on the coupling of process-based models of soil functioning processes and accommodate the peculiar properties of technogenic materials. Our work also highlights modelling features needed for pedogenesis in general: development of biological and physical models, selection of a comprehensive energy unit, dual-time scale modelling, and multi-scale representation of the soil profile. We propose (i) an adaptation of existing energy metrics (entropy, exergy, emergy or EEMT), (ii) a dual-time scale approach, our original concept, based on resilience patterns in soil changes, and (iii) the development of an existing spatial representation. Constructed Technosols are a relevant experimental model which supplies reliable data on soil evolution, data which are required for the development of pedogenic models. Technosols are emblematic of the issues we face for the management of the soils of the Anthropocene. The design of a modelling framework for Technosol evolution should therefore bring interesting developments for pedogenic modelling in general.
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Pedogenetic Trends in Soils Formed in Technogenic Parent Materials
Soil Science, 2015Co-Authors: Hermine Huot, Marieodile Simonnot, Jean-louis MorelAbstract:Abstract: Soils formed in technogenic parent materials are proliferating, and their pedogenesis remains inadequately understood. On investigation of soils formed in various technogenic materials reported in the literature and of a Technosol developing on iron industry deposits, potential specificities of pedogenesis within technogenic materials are discussed. Analyses have shown that pedogenetic processes observed in these soils are similar to those occurring in natural soils. However, some particularities have been highlighted, such as the coexistence of processes rarely encountered simultaneously in natural environments or high rates of soil development during the first stages of weathering. Technogenic materials display highly diverse constituents, wide spatial variability, and temporal discontinuities as a result of human activities. These inherent features, in interaction with other soil-forming factors, may govern pedogenesis by generating the following conditions: (i) a high diversity of pedogenetic processes, including processes occurring usually in dissimilar climatic regions; (ii) localized processes and distinct rates and orientations of soil development over short distance; and (iii) a succession and/or a superimposition of processes, constrained by the deposition of materials and human operations. This creates the potential for the simultaneity of processes coexisting rarely in natural soils developing in the same climatic region. These soils are likely to have a polycyclic evolution and to evolve toward groups of soils other than Technosols, depending on the dominant processes. Further investigations of the processes and their potential interactions occurring in a larger range of soils formed in technogenic materials are required to better predict the evolution of these soils.
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Modelling Pedogenesis in the Anthropocene
2014Co-Authors: Sophie Leguedois, Geoffroy Séré, Jérôme Cortet, Stéphanie Ouvrard, Françoise Watteau, Christophe Schwartz, Jean-louis MorelAbstract:The objective of this paper is to develop a framework for pedogenetic modelling in the Anthropocene, i.e., the present geological epoch during which humanity has become the main factor impacting the environment. We review the concepts of soil evolution as well as 15 existing quantitative models to determine the features of soil evolution modelling in an Anthropocene context. We emphasise soil-plant interactions by considering the importance of vegetation, both as a provisioning service and as a factor in soil evolution. Our review covers output variables, time scales, spatial representation, model structure, and control variables. Our synthesis in this work demonstrates that the modelling of pedogenesis in the Anthropocene requires the following specific features: (i) a description of the human impact on soil evolution, (ii) outputs related to ecosystem functions and services, (iii) the integration of a dual time scale (decade and cyclic shorter-term), (iv) multiple and interactive processes modelling, (v) the simulation of vegetation and its feedback on soils, and (vi) a representation of spatial heterogeneities, at least at the profile scale. No specific models of soil evolution in the Anthropocene have been developed thus far; however, certain required characteristics have been integrated into existing soil-plant models. Some others features will require further development, particularly a coherent and tested conceptual cornerstone that enables dual-time-scale modelling and is based on the resilience concept and energy metrics. We thus propose a general framework as a conceptual basis from which we can develop models of pedogenesis in the Anthropocene.
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characteristics and potential pedogenetic processes of a technosol developing on iron industry deposits
Journal of Soils and Sediments, 2013Co-Authors: Hermine Huot, Marieodile Simonnot, Philippe Marion, Jacques Yvon, Philippe De Donato, Jean-louis MorelAbstract:Purpose Technosols include soils dominated or strongly influenced by human-made materials. Similarly to natural soils, technogenic parent materials submitted to environmental factors undergo weathering and transformation processes. But the pedogenesis of Technosols remains little known. With this aim in view, a Technosol developing on purely technogenic materials resulting from an iron industry was thoroughly characterized in order to discuss the pedogenetic evolution of this Technosol using knowledge about the pedogenesis of natural soils.
Christophe Schwartz - One of the best experts on this subject based on the ideXlab platform.
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Ranking of wetting–drying, plant, and fauna factors involved in the structure dynamics of a young constructed Technosol
Journal of Soils and Sediments, 2018Co-Authors: Nouhou-salifou Jangorzo, Françoise Watteau, Christophe SchwartzAbstract:Purpose Dynamical in situ observation of biological and climatic structuring factors involved in pedogenesis has not previously been possible in a way that would consider the early stages of pedogenesis. If studies have explored the effect of pedogenetic factors on soil structure, none have succeeded in ranking them in view of the intensity of their effects. We propose a novel approach for describing the aggregation process for a constructed Technosol obtained from a process of pedological engineering. Materials and methods We focus on agents including plants, macrofauna, and water, and we use (i) a dynamic in situ observation and (ii) the quantification of the evolution of selected descriptors of pores and aggregates. They are quantified from high-resolution images obtained with the Soilinsight® device. Associating those images with each other, movies of interactions between soil and organisms over a 14-month non-destructive soil evolution experiment are made. Results and discussion Agents influencing aggregation—plant roots, earthworms, and water—can be ranked according to their impact on soil structure. During the studied period of evolution, wetting–drying cycles are the first to operate. The intensity of their action on soil structure is dominant at the very first stages of pedogenesis. Despite this ranking of agents, over the long term, plants and earthworms have a more intense effect on soil structure than wetting–drying cycles. Conclusions The method applied to observe and quantify soil structure dynamics is thus proposed as a helpful approach to modeling other processes involved in soil functioning and evolution in relation to their ability to fulfill ecosystem services.
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Ranking of wetting–drying, plant, and fauna factors involved in the structure dynamics of a young constructed Technosol
Journal of Soils and Sediments, 2018Co-Authors: Nouhou-salifou Jangorzo, Françoise Watteau, Christophe SchwartzAbstract:Dynamical in situ observation of biological and climatic structuring factors involved in pedogenesis has not previously been possible in a way that would consider the early stages of pedogenesis. If studies have explored the effect of pedogenetic factors on soil structure, none have succeeded in ranking them in view of the intensity of their effects. We propose a novel approach for describing the aggregation process for a constructed Technosol obtained from a process of pedological engineering. We focus on agents including plants, macrofauna, and water, and we use (i) a dynamic in situ observation and (ii) the quantification of the evolution of selected descriptors of pores and aggregates. They are quantified from high-resolution images obtained with the SoilinsightA (R) device. Associating those images with each other, movies of interactions between soil and organisms over a 14-month non-destructive soil evolution experiment are made. Agents influencing aggregation-plant roots, earthworms, and water-can be ranked according to their impact on soil structure. During the studied period of evolution, wetting-drying cycles are the first to operate. The intensity of their action on soil structure is dominant at the very first stages of pedogenesis. Despite this ranking of agents, over the long term, plants and earthworms have a more intense effect on soil structure than wetting-drying cycles. The method applied to observe and quantify soil structure dynamics is thus proposed as a helpful approach to modeling other processes involved in soil functioning and evolution in relation to their ability to fulfill ecosystem services.
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Technosol construction with by-products and wastes: pedogenesis and modelling
2016Co-Authors: Sophie Leguedois, Geoffroy Séré, Françoise Watteau, Christophe Schwartz, Apolline Auclerc, Audrey Boigné, Fabrice Bureau, Estelle Langlois, Jean-louis MorelAbstract:Technosol construction with by-products and wastes: pedogenesis and modelling. SUMMER SCHOOL ON CONTAMINATED SEDIMENTS: CHARACTERIZATION AND REMEDIATION
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Modelling pedogenesis of technosols
Geoderma, 2016Co-Authors: Sophie Leguedois, Geoffroy Séré, Jérôme Cortet, Stéphanie Ouvrard, Françoise Watteau, Christophe Schwartz, Hermine Huot, Apolline Auclerc, Jean-louis MorelAbstract:Technosols, soils subjected to a strong human influence and containing significant amounts of artefacts, are characteristic of the Anthropocene. In order to better apprehend their growing importance in our current environment, our knowledge of the evolution and fate of these soils must be improved. The aim of this article is to promote pedogenic modelling for Technosols by proposing an appropriate framework. The paper first defines the characteristics of Technosol pedogenesis, and then considers the requirements for its modelling in light of general concepts of pedogenesis, modelling tools and techniques, and 18 selected existing quantitative models. This mixed technical and conceptual analysis allows us to address at once the modelling approach, the choice of processes, the integration of control variables, the time scales, the spatial representation, and the data needed for such a framework. Technosol pedogenesis is characterised by the soils' anthropic creation, a young age, a climate globally favourable for soil evolution, a surprising level of biological activity, and mostly reactive artefacts as parent materials. Pedogenic processes observed in Technosols are similar to those occurring in more natural soils; however, they generally have fast kinetics and occur in unusual assemblages. We propose that the modelling framework for Technosol evolution should be based on the coupling of process-based models of soil functioning processes and accommodate the peculiar properties of technogenic materials. Our work also highlights modelling features needed for pedogenesis in general: development of biological and physical models, selection of a comprehensive energy unit, dual-time scale modelling, and multi-scale representation of the soil profile. We propose (i) an adaptation of existing energy metrics (entropy, exergy, emergy or EEMT), (ii) a dual-time scale approach, our original concept, based on resilience patterns in soil changes, and (iii) the development of an existing spatial representation. Constructed Technosols are a relevant experimental model which supplies reliable data on soil evolution, data which are required for the development of pedogenic models. Technosols are emblematic of the issues we face for the management of the soils of the Anthropocene. The design of a modelling framework for Technosol evolution should therefore bring interesting developments for pedogenic modelling in general.
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Modelling Pedogenesis in the Anthropocene
2014Co-Authors: Sophie Leguedois, Geoffroy Séré, Jérôme Cortet, Stéphanie Ouvrard, Françoise Watteau, Christophe Schwartz, Jean-louis MorelAbstract:The objective of this paper is to develop a framework for pedogenetic modelling in the Anthropocene, i.e., the present geological epoch during which humanity has become the main factor impacting the environment. We review the concepts of soil evolution as well as 15 existing quantitative models to determine the features of soil evolution modelling in an Anthropocene context. We emphasise soil-plant interactions by considering the importance of vegetation, both as a provisioning service and as a factor in soil evolution. Our review covers output variables, time scales, spatial representation, model structure, and control variables. Our synthesis in this work demonstrates that the modelling of pedogenesis in the Anthropocene requires the following specific features: (i) a description of the human impact on soil evolution, (ii) outputs related to ecosystem functions and services, (iii) the integration of a dual time scale (decade and cyclic shorter-term), (iv) multiple and interactive processes modelling, (v) the simulation of vegetation and its feedback on soils, and (vi) a representation of spatial heterogeneities, at least at the profile scale. No specific models of soil evolution in the Anthropocene have been developed thus far; however, certain required characteristics have been integrated into existing soil-plant models. Some others features will require further development, particularly a coherent and tested conceptual cornerstone that enables dual-time-scale modelling and is based on the resilience concept and energy metrics. We thus propose a general framework as a conceptual basis from which we can develop models of pedogenesis in the Anthropocene.
Jason Hodin - One of the best experts on this subject based on the ideXlab platform.
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Dev Genes Evol (2000) 210:358–372 © Springer-Verlag 2000 ORIGINAL ARTICLE
2013Co-Authors: Jason Hodin, Lynn M RiddifordAbstract:Parallel alterations in the timing of ovarian Ecdysone Receptor and Ultraspiracle expression characterize the independent evolution of larval reproduction in two species of gall midges (Diptera: Cecidomyiidae) Received: 30 July 1999 / Accepted: 23 Feburary 2000 Abstract Although most insects reproduce in the adult stage, facultative larval or pupal reproduction (Paedogenesis) has evolved at least six times indepently in insects, twice in gall midges of the family Cecidomyiidae (Diptera). Paedogenesis in gall midges involves the precocious growth and differentiation of the ovary in an otherwise larval form. We have previously shown that the timing of expression of the Ecdysone Receptor (EcR) and Ultraspiracle (USP), the two proteins that constitute the functional receptor for the steroid hormone 20-hydroxyecdysone, regulates the timing and progression of ovarian differentiation in Drosophila melanogaster (Diptera: Drosophilidae). Here we test the hypothesis that precocious activation of EcR and USP in the ovaries of paedogenetic gall midges allows for precocious ovarian differentiation. Using monoclonal antibodies directed against insect EcR and USP proteins, we first show that when these gall midges are reared under conditions that promote typical, metamorphic development, upregulation of EcR and USP occurs in the final larval stage. By contrast, in the paedogenetic life cycle, EcR and USP are up-regulated early in the first larval stage. A similar pattern is seen for two independently-evolved paedogenetic gall midges, Heteropeza pygmaea and Mycophila speyeri. We discuss our results in the context of developmental constraints on the evolution of Paedogenesis in dipteran insects
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parallel alterations in the timing of ovarian ecdysone receptor and ultraspiracle expression characterize the independent evolution of larval reproduction in two species of gall midges diptera cecidomyiidae
Development Genes and Evolution, 2000Co-Authors: Jason Hodin, Lynn M RiddifordAbstract:Although most insects reproduce in the adult stage, facultative larval or pupal reproduction (Paedogenesis) has evolved at least six times indepently in insects, twice in gall midges of the family Cecidomyiidae (Diptera). Paedogenesis in gall midges involves the precocious growth and differentiation of the ovary in an otherwise larval form. We have previously shown that the timing of expression of the Ecdysone Receptor (EcR) and Ultraspiracle (USP), the two proteins that constitute the functional receptor for the steroid hormone 20-hydroxyecdysone, regulates the timing and progression of ovarian differentiation in Drosophila melanogaster (Diptera: Drosophilidae). Here we test the hypothesis that precocious activation of EcR and USP in the ovaries of paedogenetic gall midges allows for precocious ovarian differentiation. Using monoclonal antibodies directed against insect EcR and USP proteins, we first show that when these gall midges are reared under conditions that promote typical, metamorphic development, up- regulation of EcR and USP occurs in the final larval stage. By contrast, in the paedogenetic life cycle, EcR and USP are up-regulated early in the first larval stage. A similar pattern is seen for two independently-evolved paedogenetic gall midges, Heteropeza pygmaea and Mycophila speyeri. We discuss our results in the context of developmental constraints on the evolution of Paedogenesis in dipteran insects.
Elizabeth Solleiro-rebolledo - One of the best experts on this subject based on the ideXlab platform.
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Late Pleistocene ‐ Holocene palaeosols in the north of Sonora, Mexico: chronostratigraphy, pedogenesis and implications for environmental history
European Journal of Soil Science, 2014Co-Authors: Tamara Cruz-y-cruz, Sergey Sedov, Guadalupe Sanchez, Teresa Pi-puig, K. Pustovoytov, Hermenegildo Barceinas-cruz, Beatriz Ortega-guerrero, Elizabeth Solleiro-rebolledoAbstract:Summary Red palaeosols of the late Pleistocene-early Holocene, both buried and non-buried, were studied recently in Sonora (NW Mexico) to reconstruct their pedogenesis as well as the palaeoenvironmental conditions. The alluvial palaeosol-sedimentary sequence of the La Playa archaeological site is a key locality for the buried San Rafael palaeosol, which exhibits a 2Ah-2Bw-2BCk-3Bgk profile and was defined as a Chromic Cambisol. Radiocarbon dates from pedogenic carbonates and charcoal set the soil formation interval between >18000 and 4300calibrated years before present (cal. year BP). Micro-morphological observations together with profile distribution of clay, carbonates, organic carbon, pedogenic iron oxides and rock magnetic properties indicated a strong eluvial-illuvial redistribution of carbonates, moderate silicate weathering and gleying in the lower horizon. Although this soil was much more developed than the overlying syn-sedimentary late Holocene Fluvisols, clay mineral composition and stable carbon isotope signatures of humus and carbonates were similar in both soils. We suggest that pedogenesis of the San Rafael palaeosol took place under a slightly more humid climate and relative geomorphic stability. This agrees with the regional palaeoclimate reconstruction, which indicates a moister climate during the Late Wisconsin glaciation (MIS 2). An abrupt termination of the San Rafael pedogenesis marked by disturbance and aridization features in the Ap horizon of the palaeosol could be linked to a global drought around 4200years cal. year BP. Surface Chromic Cambisols in northern Sonora show similar pedogenetic characteristics to the buried red palaeosols of La Playa. They appear to be a relict component of the present day soil mantle.
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Paleosol-sedimentary sequences of the Glacis de Buenavista, Central Mexico: interaction of Late Quaternary pedogenesis and volcanic sedimentation
Quaternary International, 2002Co-Authors: Elizabeth Solleiro-rebolledo, Jorge Gama-castro, D Flores Román, G. Escamilla-sarabiaAbstract:Abstract Two sections (Buenavista and Ahuatenco) of Late Quaternary paleosol-sedimentary sequences of the Glacis de Buenavista, Morelos, Central Mexico, were studied and interpreted as a regional record of climatic change and interaction of pedogenesis and volcanic sedimentation. Buenavista is the deepest section and includes seven pedostratigraphic units, with Andosol (surface unit) and Luvisol (all underlying units) types of pedogenesis. Both types indicate a humid forest environment, the divergency being related to differences in pedogenesis duration. Albeluvisol with a bleached E horizon in unit 5 indicates cooler but still moist conditions in the final Late Pleistocene, whereas strong vertic properties in unit 4 indicate a climate with contrasting seasonal variation of precipitation during the first part of the Holocene. In the upper part of the Ahuatenco section, Bt horizons of different pedogenetic events form a welded Luvisol profile instead of a set of separate paleosols due to less intensive sedimentation. Material of indurated Cm horizons (tepetates) in the lower part of the Ahuatenco section is a mixture of fresh coarse volcanoclastic components and re-deposited Luvisol clayey material, formed by mass movement associated with volcanic events. The resulting granulometric composition of these layers is favourable for structural collapse and hydroconsolidation, which caused hardening together with subsequent pedogenic illuviation and redoximorphic processes.
