Evaluation of HBV-Like circulation in wild and farm animals from Brazil and Uruguay

The origin of the hepatitis B virus is a subject of wide deliberation among researchers. As a result, increasing academic interest has focused on the spread of the virus in different animal species. However, the sources of viral infection for many of these animals are unknown since transmission may occur from animal to animal, human to human, animal to human, and human to animal. The aim of this study was to evaluate hepadnavirus circulation in wild and farm animals (including animals raised under wild or free conditions) from different sites in Brazil and Uruguay using serological and molecular tools. A total of 487 domestic wild and farm animals were screened for hepatitis B virus (HBV) serological markers and tested via quantitative and qualitative polymerase chain reaction (PCR) to detect viral DNA. We report evidence of HBsAg (surface antigen of HBV) and total anti-HBc (HBV core antigen) markers as well as low-copy hepadnavirus DNA among domestic and wild animals. According to our results, which were confirmed by partial genome sequencing, as the proximity between humans and animals increases, the potential for pathogen dispersal also increases. A wider knowledge and understanding of reverse zoonoses should be sought for an effective One Health response

Drenagem interna como fator de diferenciação de Latossolos do Distrito Federal The internal drainage as a differentiation factor in Oxisols of Distrito Federal, Brazil

O objetivo deste trabalho foi determinar a influência de características físico-hídricas dos solos em atributos diagnóstico de Latossolos. Realizou-se o levantamento de atributos morfológicos, químicos, físicos, mineralógicos e físico-hídricos de cinco perfis de Latossolos Vermelhos (LV) e cinco perfis de Latossolos Vermelho-Amarelos (LVA) petroplínticos, considerados representativos dessa classe de solos no Distrito Federal. Além da caracterização dos atributos diagnóstico, a oscilação do nível freático dos solos foi monitorada por meio de poços de observação de 2,5 m de profundidade, durante um ano. Os Latossolos estudados foram considerados semelhantes química e fisicamente. Contudo, diferiram quanto às caracterizações morfológica e mineralógica, com a presença de horizontes concrecionários e goethita nos LVA. A estabilidade da goethita nesses solos foi influenciada pela oscilação do lençol freático. Constatou-se menor condutividade hidráulica saturada e menor variação da profundidade freática nos LVA, em razão da deficiência de drenagem interna causada pela presença dos horizontes concrecionários. Os LVA apresentam, portanto, menor potencial agrícola que os LV, no Distrito Federal. As características físico-hídricas de Latossolos têm pouca influência sobre atributos diagnóstico, com exceção da mineralogia dos óxidos de ferro, que apresentam os teores de goethita aumentados em condições de baixa drenagem interna.<br>The objective of this work was to determine the influence of soil physicohydric characteristics on Oxisols diagnostic attributes. Morphological, chemical, physical, mineralogical and physicohydric attributes were surveyed in profiles of five Latossolos Vermelhos (Rhodic Haplustox, LV) and of five Latosssolos Vermelho-Amarelos (Typic Haplustox, LVA), considered representative of this kind of Oxisols in Distrito Federal, Brazil. Besides the soil diagnostic attributes characterization, the water-table oscillation was monitored using 2.5-m depth observation wells, during one year. The studied Oxisols were considered chemically and physically similar. However, they differed as to morphological and mineralogical characterization, with the presence of concretionary horizons and goethite in the LVA. Goethite stability in this soils was influenced by the water-table oscillation. The presence of concretionry horizons in LVA caused an internal drainage deficiency, which resulted in lower saturated hydraulic conductivity and lower variation of the water-table levels. Therefore, LVA soils show lower agricultural potential than LV ones, in Distrito Federal. Oxisols physicohydric characteristics have little influence on soil diagnostic attributes, except for iron oxides mineralogy, which show increased contents of goethite in low internal drainage conditions

Relações pedomorfogeológicas nas chapadas elevadas do Distrito Federal Pedomorphogeological relations in the chapadas elevadas of the Distrito Federal, Brazil

A caracterização pedológica e o entendimento das relações entre pedologia, geologia e geomorfologia são importantes para a compreensão da distribuição dos solos numa paisagem. O objetivo deste estudo foi avaliar as relações pedomorfogeológicas na região das Chapadas Elevadas do Distrito Federal (DF), mediante caracterização química, física, mineralógica e geoquímica dos solos de ocorrência nesse compartimento da paisagem. Foram selecionadas duas topossequências representativas da distribuição pedológica nas Chapadas Elevadas do DF, cujos solos foram formados a partir de rochas metassedimentares do Grupo Paranoá, representados por Latossolos Vermelhos (LV), Latossolos Vermelho-Amarelos (LVA) e Cambissolos (C). Os Latossolos das duas topossequências apresentaram a maioria dos atributos físicos, químicos e mineralógicos semelhantes. A variação da cor nesses Latossolos é proveniente da mineralogia diferenciada dos óxidos de Fe - hematita predominante nos LV e goethita nos LVA. No entanto, as análises por meio de ICP-AES apresentaram teores de Fe2O3 similares nos Latossolos, demonstrando material de origem (rochas metassedimentares) de composição geoquímica semelhante. A formação da goethita nos LVA foi considerada dependente da sua posição geomorfológica de desenvolvimento, nas bordas das chapadas, onde a oscilação do lençol freático proporcionou a formação de horizonte litoplíntico, com consequente deficiência das condições de drenagem. Os Cambissolos apresentaram-se quimicamente semelhantes aos Latossolos em razão do material de origem, que são rochas metassedimentares já pré-intemperizadas. O estudo das relações pedomorfogeológicas permitiu constatar que a distribuição dos solos nas Chapadas Elevadas do Distrito Federal é condicionada pela evolução geomorfológica e pela geologia da região.<br>Detailed studies of pedologic characterization, as well as of relationships between pedology, geology and geomorphology are important for the comprehension of the soil distribution in a landscape. The objective of this study was to evaluate the pedomorphogeological relationships in the Chapadas Elevadas of the Distrito Federal, by the chemical, physical, mineralogical and geochemical characterization of the soils found in this landscape compartment. Two representative top-sequences of the pedologic distribution were selected in this geomorphologic unit, whose soils were formed from metasedimentary rocks of the Grupo Paranoá, represented by Red Oxisols (Latosols), Yellow-Red Oxisols and Cambisols. The physical, chemical and mineralogical properties of the Oxisols of the two top-sequences were mostly similar. The color variation in the Oxisols was due to the differentiated Fe oxide mineralogy - predominantly hematite in LV and goethite in LVA. However, the ICP-AES analysis showed similar Fe2O3 levels in Oxisols, indicating a material of origin (metasedimentary rock) with similar geochemical composition. The goethite formation in LVA was related to the geomorphological position of development, on the edges of the plateau, where the water table oscillation resulted in the formation of a lithoplintic horizon, with consequently deficient drainage conditions. The Cambisols were chemically similar to Oxisols, due to the source material, consisting of pre-weathered sedimentary rock. The pedomorphogeological relations showed that the soil distribution in the Chapadas Elevadas of the Distrito Federal is linked to the geomorphologic evolution and regional geology

Hydro-physical characterization of soils under tropical semi-deciduous forest

The study of the hydro-physical behavior in soils using toposequences is of great importance for better understanding the soil, water and vegetation relationships. This study aims to assess the hydro-physical and morphological characterization of soil from a toposequence in Galia, state of São Paulo, Brazil). The plot covers an area of 10.24 ha (320 × 320 m), located in a semi-deciduous seasonal forest. Based on ultra-detailed soil and topographic maps of the area, a representative transect from the soil in the plot was chosen. Five profiles were opened for the morphological description of the soil horizons, and hydro-physical and micromorphological analyses were performed to characterize the soil. Arenic Haplustult, Arenic Haplustalf and Aquertic Haplustalf were the soil types observed in the plot. The superficial horizons had lower density and greater hydraulic conductivity, porosity and water retention in lower tensions than the deeper horizons. In the sub-superficial horizons, greater water retention at higher tensions and lower hydraulic conductivity were observed, due to structure type and greater clay content. The differences observed in the water retention curves between the sandy E and the clay B horizons were mainly due to the size distribution, shape and type of soil pores