Marcia Regina Calegari

Universidade Estadual do Oeste do Paraná | UNIOESTE · Centro de Ciências Humanas, Educação e Letras

Uma parte da história ambiental do noroeste paranaense está refletida na paisagem pela presença de paleovoçorocas de grande magnitude, ao norte do rio Ivaí, cuja gênese pode estar associada à condição climática distinta da atual, ao longo do Quaternário. Estudos na região têm apontado variações climáticas ao longo do Holoceno, indicando período mai...

Ferralsols are strongly weathered soils that cover a large part of the tropics and subtropics and have been extensively studied due to their relevance for agriculture. However, the strong focus of pedological investigations on the 2 m control section of has systematically left aside records that may exist at greater depths, which are particularly r...

Os fitólitos são estruturas microscópicas de sílica (SiO2.nH2O) produzidos nos tecidos vegetais. O interesse pelo estudo dos fitólitos tem crescido significativamente nos últimos anos no Brasil e no mundo devido a sua grande variedade de usos, desde a arqueologia até a medicina legal e por sua natureza altamente interdisciplinar. A análise fitolíti...

Purpose The objective of this study is to improve our understanding of soil organic matter (SOM) stability in Brazilian Cerrado, by interpreting soil properties at the ecosystem scale and elaborating on the interactions of biotic, climatic and edaphic controls. Methods Three 2 m soil profiles with significantly different total organic carbon TOC c...

This research was intended to interpret, by means of several empirical bases, the quaternary climate variabilities in the area of Fazenda Nova. The premise that guides the investigation is that the sedimentary fills of the weathering pits favors the understanding of the landscape and geomorphological changes in the area, by means of the investigati...

The formation and evolution processes of geomorphic surfaces remain little known in west Paraná, the western sector of the Basalt Plateau of the Paraná Sedimentary Basin. Thus, the aim of this article was to identify and investigate the evolution of geomorphic surfaces on the landscape of the extreme west of Paraná. Swath profiles were elaborated t...

Umbric ferralsols (UF) have organic carbon stocks within the first 1 m of soil profile depth that are nearly double the size (~19 kg C m−2) compared to the average carbon stocks of all other ferralsols (~10 kg C m−2). Here, we investigate processes that allow UF to gain and maintain such extraordinary carbon stocks. Using the International Soil Res...

There remains a lack of understanding on the geomorphic setting of the landscapes of the Basalt Plateau of the Paraná Sedimentary Basin (South Brazil), especially in regard to lithostructural and tectonic influence on the landscapes. Therefore, this article investigates the role of the geological framework in the evolution and configuration of the...

Macrauchenia patachonica Oiwen, 1838 is a native and extinct Quaternary megamammal from South America. Although studies on macraucheniids started two centuries ago, when Darwin found their first fossils, M. patachonica paleobiology is still poorly understood. Dental calculus is an oral pathology that fossilizes and the analysis of its contents is a...

Phytoliths are bodies of amorphous silica deposited within and between plant cells, produced by many plant families throughout their vegetative cycle, and in some situations they are the only biological markers that can be used for paleoenvironmental reconstitution (RP) studies. Currently, there is a lack of collections of references of modern plan...

A gênese dos solos está ligada a fatores presentes na paisagem, a variação nas suas características morfológicas está relacionada diretamente a diferentes processos de formação. O relevo é um dos condicionantes da pedogênese, remontando a ideia de que sua diversidade de formas influencia na formação e configuração espacial dos solos. No Sistema Bra...

Os solos fazem parte da paisagem e podem inferir sobre sua evolução. Em áreas de relevos mais estáveis é possível encontrar solos espessos e muito evoluídos pedogeneticamente, pois a natureza e a paisagem local permitiram tal evolução. Os solos guardam registros da sua evolução e através de seus atributos é possível inferir sobre seu atual estágio...

This proposal has the main objective of defining the phytolytic signature (fingerprint) of four forested phytophysiognomies of the Brazilian Atlantic Forest biome (Alto-Montana-FOAM Rainforest, Semideciduous Forest-FES, Mata de Restinga-MR and Cerradão). Labels were collected in each area, with four replicates, litter and horizontal topsoil (0-5 cm...

Variations in relief associated with pedogenetic processes promote different intensities in weathering of sediments of the Barreiras Formation and may thus lead to the formation of different soil types, like Podzols, Acrisols and Ferralsols. The Podzols of tropical regions contain important information on climate and vegetation changes that occurre...

Soil is the largest carbon reservoir on the planet's surface, containing about three times more carbon than the atmosphere and terrestrial vegetation. The estimation of soil organic carbon (SOC) stock is highly variable and most studies focus on intervals in the upper 1 m and on agricultural areas. However, the major part of SOC is found in forest...

This study aims to contribute toward a better understanding of the current biodiversity patterns existing in the Atlantic Forest of the state of Rio de Janeiro from a paleo-ecological approach. Three soil profiles, each formed from distinct source materials under varied climate and vegetation conditions were selected from the coastal regions of Rio...

The formation of sombric horizons (dark horizons in the subsoil) is still not understood. In order to improve our understanding of the formation of sombric horizons we studied these soils in southern Brazil from various perspectives. The lateral configuration and grain size distribution excluded the possibility that the sombric horizon is a paleoso...

No período Quaternário, o Sul do Brasil passou por instabilidades paleoclimáticas que geraram mudanças nas paisagens. Estudos pedológicos, sedimentológicos e de reconstrução paleoambiental têm sido desenvolvidos pelo grupo Gênese e Evolução de Superfícies Geomórficas e Formações Superficiais (UNIOESTE-FB) para investigar a hipótese da influência pa...

Em vários estudos de microfósseis as análises polínicas e isotópicas, entre outras técnicas, são utilizadas como meios para investigar o comportamento climático e suas implicações nos paleoambientes. A essas técnicas de investigação, soma-se a análise fitolítica, utilizada para complementar os estudos do Quaternário. Fitólitos são corpos de sílica...

A truthful vegetation reconstruction is essential for understanding the historical trajectory of climate change and as well as the nature and extent of human impact on ecosystems. A classical approach to these studies is the use of pollen to identify flora composition and variability over time. However, the use of pollen is not always viable due to...

The Araucarias Plateau is a geomorphological unit that occupies approximately three-quarters of the terrain in the southern area of South Brazil, between the Iguazu and Uruguay Rivers. The plateau displays different altitudinal levels (600 to <1400 m a.s.l.) that are locally recognized as remnants of incomplete planation surfaces. These surfaces ar...

Estudos paleoambientais desde ~50.000 anos na costa do Brasil e, em particular, no litoral do Espírito Santo, são ainda insuficientes para servir de base a reconstituições da dinâmica da vegetação, de oscilações do nível relativo do mar e de flutuações climáticas e respectivas influências sobre a ação humana milenar. Para obter essas informações, u...

O presente artigo visa reconstruir paleoperfis de alteração a partir dos sedimentos de depósito de articulação encosta/calha fluvial no Planalto de Palmas/Água Doce durante os 41.000 anos AP. Foram empregadas análises granulométricas, químicas e mineralógicas da fração argila em seção previamente caracterizada. Reconheceram-se quatro momentos disti...

Resumo: O presente artigo visa reconstruir paleoperfis de alteração a partir dos sedimentos de depósito de articulação encosta/calha fluvial no Planalto de Palmas/Água Doce durante os 41.000 anos AP. Foram empregadas análises granulométricas, químicas e mineralógicas da fração argila em seção previamente caracterizada. Reconheceram-se quatro moment...

Interdisciplinary palaeoenvironmental studies in the late Quaternary on the Brazilian coast and, in particular, on the Espirito Santo coast, Southeastern region, are still insufficient to serve as a basis for the reconstruction of the dynamics of vegetation, of relative sea level oscillations and climatic fluctuations and their respective influence...

Fitólitos é uma poderosa ferramenta em estudos de reconstrução da vegetação e pode informar às condições ambientais pretéritas de formação dos solos. O objetivo dessa pesquisa foi analisar essas biomineralizações de amostras superficiais de solos e de um perfil de Argissolo Amarelo em Iranduba, AM. Serrapilheira e solo (0-5 e 5-10 cm) foram coletad...

An interproxy approach focused on phytoliths and pollen, including radiocarbon dating and sediment particle-size analyses, has been carried out at Lagoa do Macuco, Linhares municipality, Espírito Santo State, Brazil. Three pollen zones were identified: the first one (MAC-C I) indicates the presence of mangrove vegetation between 7700 cal yr BP and...

Um testemunho de 12 metros de profundidade e idade de ~47260 anos cal AP na sua base foi coletado na planície deltaica do litoral norte do estado do Espírito Santo. Esse trabalho teve como principal objetivo a caracterização do conjunto de fitólitos, auxiliado pelas fácies sedimentares, dados isotópicos (C e N) e datações 14C para reconstituir o pa...

As causas e efeitos da instabilidade da paisagem da regiao Oeste do Parana, ate o momento, sao pouco conhecidos, assim como os demais componentes do meio fisico regional. Atraves da analise da paisagem, ressaltando as relacoes ente a cobertura e a morfologia do relevo realizou-se o estudo da distribuicao da cobertura pedologica ao longo de uma topo...

Studies on phytoliths and their applications in environmental, archaeological and ethno-botanical studies aimed at the reconstruction of Quaternary paleoenvironments came to the fore in Brazil at the beginning of the 21st century, despite already being a well known technique in other countries. Phytolith studies were developed along with analyses o...

This article presents results of simultaneous application of soil carbon isotopes and phytoliths analysis to identifi cation of vegetation changes with climate change inferences from Late Quaternary, associated with the evolutionary dynamics from one of the second-order hierarchical paleovalleys of Surface 2 in Araucarias Plateau. The stratigraphic...

Many plants deposit the soluble silica absorbed from the soil as monosilicic acid (H4SiO4) in and between their cells, generating bodies of opal silica (SiO2·nH2O) called phytoliths. Although phytoliths are susceptible to dissolution under extreme pH conditions, they generally do remain in the soil for long periods of time and can help in the recon...

The analysis of phytolith assemblages is an important method in studies that uses the soil as an environmental record in order to reconstruct the paleoclimatic conditions. Despite being underused in soil science, this technique is used complementary to the analysis of pollen and other microfossils, as well as to evaluate silicon reserves in the soi...

Presentase la evolución de cuencas de bajo orden jerárquico en el Planalto de Palmas/Água Doce (Sur de Brasil) en los últimos 41.000 años A.P. a partir de los registros de la sección estratigráfica HS1. Se hizo la descripción de unidades litológicas y edáficas, análisis micromorfológico y dataciones radiocarbónicas. Se identificaron unidades litoló...

The article presents the low-order drainage basins evolution in Palmas/Agua Doce plateau (South of Brazil) during the last 41,000 years B.P from the registers of stratigraphic section (HS1). Lithological and pedagogical units, micromorphological analysis and dating by 14C were described. Alluvial facies lithologic, colluvial/alluvial, colluvial and...

The occurrence of Umbric Ferralsols with thick umbric epipedons (> 100 cm thickness) in humid Tropical and Subtropical areas is a paradox since the processes of organic matter decomposition in these environments are very efficient. Nevertheless, this soil type has been reported in areas in the Southeast and South of Brazil, and at some places in th...