Microrrelevos: formas e processos pedogeomorfológicos com ênfase em gilgais em ambiente semiárido
Microreliefs are present in several terrestrial ecosystems, including on other planets, such as Mars. These can be indicators of environments with a greater presence of humidity (such as in semi-arid regions), they can be indicators of the presence of expansive clays (2:1), bioturbation or the occur...
| Published in: | Geography Department University of Sao Paulo |
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| Main Authors: | , , , |
| Format: | Article in Journal/Newspaper |
| Language: | Portuguese |
| Published: |
Universidade de São Paulo. Faculdade de Filosofia, Letras e Ciências Humanas
2024
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| Subjects: | |
| Online Access: | https://revistas.usp.br/rdg/article/view/225601 https://doi.org/10.11606/eISSN.2236-2878.rdg.2024.225601 |
| Summary: | Microreliefs are present in several terrestrial ecosystems, including on other planets, such as Mars. These can be indicators of environments with a greater presence of humidity (such as in semi-arid regions), they can be indicators of the presence of expansive clays (2:1), bioturbation or the occurrence of permafrost (in periglacial environments). In the national literature there is a large gap regarding the gilgal microreliefs of the Brazilian semi-arid region. The objective of this study was to analyze the genesis, morphology and features associated with microreliefs, in different terrestrial environments, with an emphasis on gilgais in semi-arid environments based on a bibliographic review study. In areas with microreliefs, soil disturbance occurs in a widespread manner, being associated with freezing, bioturbation, or clay disturbance. In this way, the opening of preferential paths for water percolation (through cracks or channels) is remarkable. In semi-arid tropical environments, the primordial process for the genesis of gilgais is associated with the presence of expansive clays with high activity and accumulation models with a greater occurrence of wetting and drying cycles. Landscapes with microreliefs have in common a complexity of pedological and geomorphological processes, which in order to better discover interscalar relationships, from macro to micro and vice-versa. Os microrrelevos estão presentes em diversos ecossistemas terrestres, inclusive em outros planetas, como Marte. Os microrrelevos podem ser indicadores de ambientes com maior presença de umidade, como encontrado em regiões semiáridas. Podem, ainda, serem indicadores da presença de argilas expansivas (2:1), de bioturbação ou da ocorrência de permafrost, estes em ambientes periglaciais. Na literatura nacional, há uma lacuna sobre os microrrelevos, sobretudo aos gilgais presentes no semiárido brasileiro. O objetivo desse estudo foi analisar a gênese, a morfologia e as feições associadas a microrrelevos, em distintos ambientes terrestres, ... |
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