Navegando por Autor "Schaefer, Carlos Ernesto Gonçalves Reynaud"

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Biodiversity and ecosystem services in the campo rupestre : a road map for the sustainability of the hottest Brazilian biodiversity hotspot.
(2020) Fernandes, Geraldo Wilson Afonso; Garcia, Lucas Arantes; Silva Júnior, Milton Barbosa da; Barbosa, Newton Pimentel de Ulhôa; Batista, Eugênia Kelly Luciano; Silva, Wallace Beiroz Imbrosio da; Resende, Fernando de Moura; Abrahão, Anna; Almada, Emmanuel Duarte; Alves, Elaine; Alves, Natacha Jordania da Silva; Angrisano, Patrícia; Arista, Montserrat; Arroyo, Juan; Arruda, André Jardim; Bahia, Thaíse de Oliveira; Braga, Laura; Brito, Lilian de Almeida; Pereira, Marcos Callisto de Faria; Paiva, Dario Caminha; Carvalho, Marilia; Conceição, Abel Augusto; Costa, Lêda Naiara Pereira; Cruz, Antônio Jorge do Rosário; Blum, Jessica Cunha; Dagevos, John; Dias, Braulio Ferreira de Souza; Pinto, Victor Diniz; Dirzo, Rodolfo; Domingos, Daniel Quedes; Andrade, Livia Echternacht; Fernandes, Stephannie; Figueira, José Eugênio Côrtes; Fiorini, Cecília Fonseca; Giulietti, Ana Maria; Gomes, Augusto; Gomes, Vanessa Matos; Gontijo, Bernardo Machado; Goulart, Fernando Figueiredo; Guerra, Tadeu José de Abreu; Junqueira, Patrícia A.; Santos, Débora Lima; Nascimento, Julia Marques; Meira Neto, João Augusto Alves; Miola, Deise T. B.; Morellato, Leonor Patricia Cerdeira; Negreiros, Daniel; Paula, Elizabeth Neire da Silva Oliveira de; Neves, Ana Carolina; Neves, Frederico de Siqueira; Novais, Samuel Matos Antunes de; Oki, Yumi; Oliveira, Elizabeth; Oliveira, Rafael Silva; Pivari, Marco Otávio Dias; Pontes Junior, Euripedes; Ranieri, Bernardo Dourado; Ribas, Rodrigo Pinheiro; Scariot, Aldicir Osni; Schaefer, Carlos Ernesto Gonçalves Reynaud; Sena, Letícia; Silva, Pedro Giovâni da; Siqueira, Paulo Ricardo; Soares, Natalia Costa; Soares Filho, Britaldo Silveira; Solar, Ricardo Ribeiro de Castro; Tabarelli, Marcelo; Vasconcellos, Rogério Pinto; Vilela, Evaldo Ferreira; Silveira, Fernando Augusto de Oliveira e
Global sustainability rests on a myriad of benefits provided by natural ecosystems that support human livelihoods and well-being, from biodiversity persistence to climate regulation. The undeniable importance of conserving tropical forests has drawn most of the conservation spotlight towards it. However, open ecosystems such as the Brazilian Campo Rupestre (rupestrian grassland), have been historically overlooked despite their high diversity and key associated ecosystem services. We highlight major current threats to the persistence of the Campo Rupestre emphasizing its ecological, social, cultural, geoenvironmental, and economic importance. We call attention to the importance of the Campo Rupestre as a reservoir of biodiversity and ecosystem services and offer priority actions that resulted from discussions involving scientists, industry representatives, environmental managers, and other members of civil society. Proposed actions include efforts related to ecological restoration, sustainable ecotourism, protection of traditional ecological knowledge, identification of emerging research questions, and development of tailored public policies. Such issues are integrated into a framework that collectively represents a road map to safeguard the Campo Rupestre from further degradation and steer its historical overexploitation towards sustainable management. Safeguarding the future of non-forest biomes like this poses a challenge to current paradigms of nature conservation. By establishing priorities and guidelines, we propose an actionable plan, which we hope can support informed decision-making policy towards a sustainable use of the Campo Rupestre.
Ecology and evolution of plant diversity in the endangered campo rupestre : a neglected conservation priority.
(2016) Silveira, Fernando Augusto de Oliveira e; Negreiros, Daniel; Barbosa, Newton Pimentel de Ulhôa; Buisson, Elise; Carmo, Flávio Fonseca do; Carstensen, Daniel Wisbech; Conceição, Abel Augusto; Cornelissen, Tatiana Garabini; Andrade, Livia Echternacht; Fernandes, Geraldo Wilson Afonso; Garcia, Queila de Souza; Guerra, Tadeu José de Abreu; Jacobi, Cláudia Maria; Lemos Filho, José Pires de; Stradic, Soizig Le; Morellato, Leonor Patricia Cerdeira; Neves, Frederico de Siqueira; Oliveira, Rafael Silva; Schaefer, Carlos Ernesto Gonçalves Reynaud; Viana, Pedro Lage; Lambers, Hans
Background Botanists, ecologists and evolutionary biologists are familiar with the astonishing species richness and endemism of the fynbos of the Cape Floristic Region and the ancient and unique flora of the kwongkan of south-western Australia. These regions represent old climatically-buffered infertile landscapes (OCBILs) that are the basis of a general hypothesis to explain their richness and endemism. However, few ecologists are familiar with the campo rupestre of central and eastern Brazil, an extremely old mountaintop ecosystem that is both a museum of ancient lineages and a cradle of continuing diversification of endemic lineages.
Formação de solos de sambaquis no litoral sul do Espírito Santo : um estudo pedoarqueológico no ameaçado Sítio Rio Preto 1.
(2021) Ladeira, Angélica de Cássia; Oliveira, Fábio Soares de; Schaefer, Carlos Ernesto Gonçalves Reynaud; Souza, Caroline Delpupo; Oliveira, Fábio Soares de; Varajão, Angélica Fortes Drummond Chicarino; Oliveira, Cristiane Valéria de
Sambaquis são formações artificiais constituídas principalmente por conchas, contendo vestígios de alimentação humana, restos de fauna terrestres, ossos de peixes, artefatos líticos e cerâmicos e às vezes sepultamentos humanos. Os sambaquis são encontrados ao longo de todo o litoral brasileiro e algumas planícies aluviais amazônicas. Construídos por grupos de caçadorescoletores, serviam principalmente como moradia e cemitério. Nos sambaquis formam-se solos enquadrados como arqueoantrossolos, cuja gênese está ligada às atividades humanas antigas. Outros arqueoantrossolos são as Terras Pretas Arqueológicas, Terra Mulata e solos sob abrigos. Este trabalho realizou um estudo pedoarqueológico para compreender a formação de solos no sambaqui Rio Preto 1 localizado no litoral sul do estado do Espírito Santo. Foram selecionados dois perfis para estudos, um no topo e outro na base do sambaqui e perfis que continham fogueiras. Foram coletadas amostras representativas de cada horizonte, além de carvão, restos de fogueiras e concreções. As amostras foram submetidas às análises químicas e físicas de rotina, fluorescência de raios-x, mineralogia por difração de raios-x, micromorfologia, microssonda eletrônica e datação por C14. De acordo com os resultados, os solos do sambaqui Rio Preto 1 são pedogeneticamente pouco desenvolvidos, formados sobre o amontoado de conchas, e têm suas propriedades relacionadas tanto às atividades humanas que ali se desenvolveram, quanto aos processos pedogenéticos pósdeposicionais. Os principais fatores responsáveis pela formação do solo foram material de origem, organismos, topografia e atividade antrópica e os processos identificados foram melanização, estabilização da matéria orgânica, lessivagem, podzolização e cimentação induzida. De maneira geral, os solos apresentaram cores escuras com valor baixo, textura esquelética com predomínio da fração grossa. Quimicamente, possuem altos valores de pH, Ca, Mg, K, P e COT, assim como a expressiva participação SiO2, Al2O3, P2O5 e Fe2O5, e CuO na composição química total. Ocorrem os minerais calcita, aragonita, halita, hidroxiapatita e picos discretos de maghemita. Micromorfologicamente, ocorrem revestimentos carbonáticos e orgânicos ao redor das conchas, confirmando a migração de partículas finas. As fogueiras estudadas influenciaram nas propriedades dos solos e modificaram os substratos dos cocheiros criando núcleos de consistência dura. Os solos estudados foram classificados como NEOSSOLOS LITÓLICOS Carbonáticos “antropogênicos” pela SiBCS, Pretic Anthrosol Orthoeutric, Protocalcic, Technoskeletic pela WRB e Arqueoantrossolo Tâmbico, ebânico, endoêutrico, esquelético, carbonático e Arqueoantrossolo Tâmbico, cinzento, endoêutrico, esquelético, carbonático pela chave de classificação proposta por Kämpf et al (2003). O sambaqui Rio Preto 1 é, até o momento, o sambaqui mais antigo do litoral sul do Espírito Santo, com mais de 6 mil anos. Devido sua fragilidade e importância como testemunhos da história, são necessárias medidas urgentes para sua proteção e integridade, considerando que se encontra altamente ameaçado.
Geochemical evolution of soils developed from pyroclastic rocks of Trindade Island, South Atlantic.
(2021) Mateus, Ana Carolina Campos; Varajão, Angélica Fortes Drummond Chicarino; Oliveira, Fábio Soares de; Petit, Sabine; Schaefer, Carlos Ernesto Gonçalves Reynaud
The geochemical behavior of the major, minor, trace and rare earths elements (REEs) in soil profiles from ultramafic volcanoclastic rocks of the Vulcão do Paredão and Morro Vermelho Formation from Trindade Island (TI) was analyzed in this study. Losses and gains of chemical elements were calculated through the mass balance for two profiles along the slope: one located at higher altitude (460 m) and the other at lower altitude (258 m). In all profiles, Al, Fe and Ti accumulate due to their low mobility, whereas Ca, Na, K and Mg are the most intensely leached. Soils located at lower altitude show higher K and Mg values in the surface due to the contribution of saline sprays. Leaching of the REEs from higher to the lower slope led to the enrichment of these elements, especially the light REEs, in the soil at the lowest altitude (258 m). The high altitude profile showed Ce positive anomaly due to longer exposure to weathering. The geochemical balance shows a relative enrichment of Ti, Mn, Fe, Co, Cr, Ni, V, Zr, S related to the loss of mobile elements during the soil formation process, despite the youthful nature of these volcanic rocks.
Geochemistry of Antarctic periglacial soils from Harmony Point, Nelson Island.
(2021) Rodrigues, William Fortes; Oliveira, Fábio Soares de; Schaefer, Carlos Ernesto Gonçalves Reynaud; Araújo, Teodoro Gauzzi Rodrigues de; Leite, Mariangela Garcia Praça
Little is known about the geochemical baseline of Antarctic soils in diferent environments. We investigated the soil geo- chemistry of the two main landscape units of Harmony Point (Nelson Island, Maritime Antarctica): the coastal domain and the upper platform. Fourteen soil samples (seven in each landscape unit) were divided according to depth (hA for surface and hC for subsurface horizons) and characterized by their major, trace elements and REE concentrations. The concentration of major elements (SiO2, TiO2, Al2O3, Fe2O3, MgO, CaO, MnO, and K2O) were determined by X-ray fuorescence, whereas trace elements were quantifed by inductively coupled plasma-optical emission spectrometry (Co, Ni, As, Cd, Pb, Ba, Cr, Cu, V, Zn, and Zr) and REE by inductively coupled plasma mass spectrometry. The results showed geochemical variation with depth, either related to pedological processes (phosphatization, humifcation, podzolization, and cryoturbation), and parent material constitution (andesitic basalt in upper platform and mixed volcanic sediments in coastal domain). The main chemical aspects distinguishing Harmony Point soils from other Maritime Antarctic soils from the vicinity are: (i) higher CIA index; (ii) P2O5 enrichment due to bird guano and enhanced pedogenesis; (iii) REE retention; (iv) enrichment in Fe2O3 and S concentrations. The REE concentration was infuenced by weathering processes combined with allochthonous inputs, such as volcanic ashes and iceberg-transported granitic boulders at the coastal domain. The Harmony Point soils are little subjected to anthropic impacts, so they can be used as a basis for environmental monitoring programs in the Maritime Antarctica region.
Mineralogical and geochemical signatures of Quaternary pyroclasts alterations at the volcanic Trindade Island, South Atlantic.
(2020) Mateus, Ana Carolina Campos; Varajão, Angélica Fortes Drummond Chicarino; Petit, S.; Oliveira, Fabio Soares; Schaefer, Carlos Ernesto Gonçalves Reynaud
This paper reports the composition and alteration products of pyroclasts in the Holocene Paredão volcano (pyroclast 1) and Late Quaternary Morro Vermelho Formation (pyroclasts 2 and 3) of Trindade Island, South Atlantic, Brazil using combined macromorphological, micromorphological, mineralogical and geochemical techniques. The pyroclasts 1 and 2 are interpreted as volcanic tuff breccia deposits, whereas pyroclast 3 is a lapilli deposit. They are dark gray in color with some altered reddish regions and show vesicles and amygdales structures with small greenish crystals of 2.0 mm scattered throughout the matrix. The eruptions can be regarded as Strombolian-type by producing pyroclastic deposits with coarse fragments with high vesicularity and fluidal shape that indicate magmatic degassing and fragmentation. Petrologic and XRD data revealed a mixture of biotite, goethite, ilmenite, anatase, magnetite, hematite, pyroxene, zeolites, and olivine as their main mineral components. Optical microscopy analysis confirms the vesicular and amygdaloid structures, with a hypocrys- talline texture and a pale brown stained vitreous mass classified as sideromelane, due to its basaltic composition. The sideromelane changes to a reddish brown and yellowish-brown staining material identified as palagonite, clearly indicating a hydrovolcanic eruption that occurs when the ascending magma comes into contact with water. Infrared analyses in the palagonitized regions revealed the presence of halloysite, suggesting alteration of sideromelane to tubular clay minerals. Amygdales and microfractures are partially or totally filled with zeolites, which are formed by the percolation of water that reacts with the palagonite and precipitation of chemical elements of hydrothermal fluid. Reddish dark brown iddingsite and anhedral crystals of titaniferous magnetites occur in the fractures and edges of the olivine. These crystals are also dispersed in the matrix while some of them are zoned with Cr-rich core and Cr-poor edge, suggesting a deep mantle origin of the magma. The high trace elements content can be related to clinopyroxene (diopside) that include these elements. Geochemical data show that the pyroclasts are undersaturated in silica, plotting in the ultrabasic and foidites fields on the TAS classification diagram.
Non-allophanic Andosols of Trindade Island, south Atlantic : a new soil order in Brazil.
(2020) Mateus, Ana Carolina Campos; Varajão, Angélica Fortes Drummond Chicarino; Oliveira, Fábio Soares de; Petit, Sabine; Schaefer, Carlos Ernesto Gonçalves Reynaud
The pedological studies carried out so far in Trindade Island (TI) have obtained patchy evidences of allophane, without detailed mineralogical and micromorphological studies to confirm the occurrence of Andosols in TI. Therefore, in this study, the mineralogical, micromorphological, physical and chemical characterization of four soil profiles from Vulcão do Paredão (P1) and Morro Vermelho formations (P2, P3, and P4) were carried on the latest volcanic events in Brazil from Trindade Island (TI) with the aim of to evaluate the presence of Andosols in this oceanic island. Profiles P1 and P2 are developed on pyroclastic bombs, and show, respectively, A-Bi- C and decapitated A-C horizons, whereas P3 and P4 are developed on lapillitic and bomb pyroclasts, show A-C horizons. The soil profiles have a reddish and brownish clayey matrix, are highly friable and show a plastic consistency. Their microstructures are granular, single grain and intergrain microaggregate, in which aggregates display an undifferentiated b-fabric. The mineralogical constituents of the bulk fraction are biotite, hematite, magnetite, ilmenite, pyroxene, olivine, halloysite, goethite, anatase, and rutile. The clay fraction is marked by the presence of halloysite, ferrihydrite, and little amounts of allophane. All soils presented andic properties and can be classified as non-allophanic Andosols. In addition, micromorphological features closely resemble those reported in Andosols from other volcanic islands from elsewhere. The predominance of halloysite in the clay fraction formed by alteration of sideromelane, suggests that allophane would be an intermediate phase of this rapid transformation favored by the wet climate conditions of the highest parts of TI.
Phosphatization under birds’ activity : ornithogenesis at different scales on Antarctic Soilscapes.
(2021) Rodrigues, William Fortes; Oliveira, Fábio Soares de; Schaefer, Carlos Ernesto Gonçalves Reynaud; Leite, Mariangela Garcia Praça; Pavinato, Paulo Sérgio
Extensive areas of penguins’ nesting (Pygoscelis sp.), on ice-free areas, account for vast deposits of organic matter- rich guano in maritime Antarctica. One such area, at Harmony Point, currently houses different penguin colonies with extensive and unique ornithogenic soils, where phosphatization is the key soil-forming process. We sought to enhance the knowledge of phosphatization process, products, cycles, and phosphorus (P) forms in these un- usual soils. We compared ornithogenic and non-ornithogenic soils, based on advanced chemical, micromor- phological and mineralogical analyses of samples of guano and phosphate biocrusts, complete with P and OM fractionation. Ornithogenic soils have the organic P-pool as the largest phosphorous compartment, followed by varying P-Ca forms. In contrast, soils unaffected by phosphatization showed a high inorganic P-pool. Penguin guano is enriched with P, Ca, K, Cu, Zn, C and N. The phosphatic biocrusts are composed of struvite and hy- droxyapatite, forming a gradient of phosphate forms. We recognized three different phosphatization environ- ments, namely (i) present-day marine birds’ rookeries, (ii) adjacent zone of rookeries and (iii) abandoned rookeries. Geomorphological evolution of the coastal areas, by Holocene glacier retreat, resulted in the changing location of penguin colonies, resulting in a larger area and varying ages of phosphatization, forming ornithogenic soils with contrasting evolution degrees. Abandoned areas have greater vegetation growth, with higher diversity.
Phosphatized volcanic soils of Fernando de Noronha Island, Brazil : paleoclimates and landscape evolution.
(2020) Silveira, Jonas Carvalho; Oliveira, Fabio Soares; Schaefer, Carlos Ernesto Gonçalves Reynaud; Varajão, Angélica Fortes Drummond Chicarino; Varajão, Cesar Augusto Chicarino; Senra, Eduardo Osório
Volcanic oceanic islands host soils that may hold important paleo-environmental proxies, based on vegetation and faunal evidences coupled with pedological and geomorphological indicators. In this regard, the main Brazilian oceanic island of Fernando de Noronha (FNI) still lacks a deeper and more complete analysis of its climatic history and soil evolution. We select and collect representative FNI soils to interpret their chemical, physical and mineralogical properties and to explain their changing pedogenesis and geomorphic balance, aiming at revealing the environmental and landscape evolutionary history of this island. Ten soil pedons on phonolites, ankaratrites and the associated pyroclastic rocks were collected in June/2018. Six profiles were classified as Inceptisols, one as Entisol, one as Mollisol, one as Vertisol and another as the first Oxisol ever described in a Brazilian oceanic island. The pH ranged between 5.0 and 6.0 in the more developed, dystrophic and Al-saturated soils, whereas alkaline pHs were found in the eutrophic and Na-rich pedons. For the latter group, chemical and physical attributes are closely associated with the parent material composition, whereas in the former, present day soil features overprint paleoweathered regoliths and former pedogenetic processes. High concentrations of available phosphorus (P) were observed in all soils and horizons, even at depths greater than 150 cm, and P forms were detected as amorphous or poorly-crystalline phosphates (Al, Fe, Na, Ca and K). High- and low-activity clay minerals coexist, combined with gibbsite and unstable primary minerals, indicating the polygenetic nature of FNI soils. A combined pedogeomorphological analysis indicated the existence of a high paleoweathered plateau with relict soils, and erosional surfaces hosting younger soils. Results showed the succession of at least three distinct main paleoclimates since the Pliocene and a post-magmatic model for landscape evolution. The unreported, widespread and intense phosphatization of all soils and paleosurfaces is attributed to a past large population of birds nesting all over the island, corroborating old historical records of the island’s early occupation. Report the occurrence of Brazil’s first ornithogenic Oxisol with more than 500 mg/ kg of bioavailable P.
Soil-chronosequence and quaternary landscape evolution at the marine terraces of Harmony Point, Nelson Island, Maritime Antarctica.
(2022) Rodrigues, William Fortes; Machado, Mariana de Resende; Oliveira, Fábio Soares de; Schaefer, Carlos Ernesto Gonçalves Reynaud; Leite, Mariangela Garcia Praça; Michel, Roberto Ferreira Machado; Araújo, Teodoro Gauzzi Rodrigues de
This study characterized the physical, chemical, macro- and micromorphological soil properties from three successive marine terrace levels from Harmony Point (Nelson Island, Maritime Antarctica) in order to understand the pedological signatures of Quaternary coastal landscape evolution of Maritime Antarctica. Soils were sampled on the Late Holocene beach (current beach) and Mid Holocene marine terraces higher up, at 3, 8, and 12 m a.s.l. At the lower levels, the predominant soils were Gelorthents, whereas Haplogelepts dominate the higher terraces. Soil properties are mostly influenced by parent material and faunal activity, in which cryoclastic (thermal weathering) and phosphatization are the main soil-forming processes. Soils from the upper levels are more developed, deeper with reddish colors, granular structures and incipient formation B horizon. These horizonation features highlight that soils vary according with age of glacier-isostatic terrace uplift, representing a Quaternary soil chronosequence. All marine terrace levels are Ornithogenic soils, at varying degrees. However, the presence of old bird nesting sites for long periods led to formation of phosphatic horizons, stable Fe-phosphate minerals and abundant vegetation in the highest terraces of this part of Maritime Antarctica.
Soil-landscape interplays at Harmony Point, Nelson Island, Maritime Antarctica : chemistry, mineralogy and classification.
(2019) Rodrigues, William Fortes; Oliveira, Fábio Soares de; Schaefer, Carlos Ernesto Gonçalves Reynaud; Leite, Mariangela Garcia Praça; Araújo, Teodoro Gauzzi Rodrigues de; Bockheim, James G.; Putzke, Jair
Soils and landforms of Nelson Island remain one of the least studied in the South Shetlands Archipelago, despite that it is one of the oldest ice-free areas and is strongly vegetated. In this paper, we examine the main processes and factors of soil formation at Harmony Point and the relation of soils to landforms, vegetation and lithology. To achieve the goals, 26 pedons were collected and studied from a 4 km2 ice-free area at Harmony Point (S62°18′; W059°10′) on the southern area of Nelson Island (Maritime Antarctica). The soils were sampled on all representative local landforms, including three levels of uplifted marine terraces up to cryoplanated plateau, waterlogged depressions, rock felsenmeer, debris slopes and patterned ground, and a paraglacial border of the ice cap (270 m a.s.l). Sampling along the cryoplanated plateau was carried out along a gradient extending inland from the margins of the Ice Cap; and sampling of the marine terraces was performed along a chronosequence under varying bird-nesting influence and age. The main pedogenetic processes observed in this area are marked phosphatization, melanization from the accumulation of organic matter, and cryoturbation. Soil development varies from weakly developed, shallow, stony and cryoturbated to well-developed and organic-rich, phosphate soils with colors ranging from grayish to brown. The mineralogical composition of the clay fraction contains secondary minerals, indicating the active role of chemical weathering. Ornithogenic soils have mature phosphate minerals such as vivianite and taranakite, as well as poorly crystalline leucophosphite. Intensively cryoturbated soils are underlain by permafrost and are classified as Typic Haploturbels; polygonal soils are widespread on the cryoplanated plateau. Areas without permafrost were classified as Typic Gelorthents. Phosphatization is a dominant soil-forming process in this area and is associated with past and present-day guano accumulation by bird nesting and has led to the the development of deeper Ornithogenic Haplorthels. The ornithogenic soils occur at different topographic levels on the cryplanated platform and marine terraces. High P concentrations can be used as a proxy of the past nesting birds' activities, with far-reaching implications, especially with regards to vegetation growth and microbial activity and diversity.
The role of biological agents in the microstructural and mineralogical transformations in aluminium lateritic deposit in Central Brazil.
(2014) Oliveira, Fábio Soares de; Varajão, Angélica Fortes Drummond Chicarino; Varajão, César Augusto Chicarino; Schaefer, Carlos Ernesto Gonçalves Reynaud; Boulangé, Bruno
Petrological studies using X-ray diffraction (XRD) and micromorphological analyses (Optical Microscopy and SEM), were done to understand the role of biological activity in the evolution of Barro Alto bauxite. The results indicated that this influence came through structural (or microstructural) and mineralogical transformations, namely: I — the bioturbation caused by termites and II — themechanical degradation and geochemical transformation promoted by roots. In the bioturbation caused by termiteswere formed: I — a intergrainmicro-aggregate structure, characterised by gibbsite crystals from isalteritic bauxite fragmentation on the bottom of the profile and II — a granular structure characterised by a termitic microaggregates with fragments of gibbsite immersed in a kaolinite–gibbsite–goethite–boehmite micromass, formed by bioturbation of the degradation clay with nodules of gibbsite,whose origin is the geochemistry degradation of isalteritic bauxite. The processes associatedwith geochemical andmechanical degradation caused by roots were responsible for the genesis of: I—a porphyric texture with bauxite fragments surrounded by nonaggregate material and II — fine monic structure where the gibbsite neoformation has the mould cavities left by old roots, generating riziform features.