Reis, João SantiagoLira, Damião Isaac de2022-07-262022-07-262022-07-21LIRA, Damião Isaac de. Morfologia de microrrelevos Gilgai na região de Caicó - RN. 2022. 50 f. Trabalho de Conclusão de Curso (Bacharelado em Geografia) - Departamento de Geografia, Centro de Ensino Superior do Seridó, Universidade Federal do Rio Grande do Norte, Caicó, 2022.https://repositorio.ufrn.br/handle/123456789/48741The Gilgai microrelief is characterized by an alternation of microhighs and depressions on the soil surface, generally with a clayey texture with the presence of smectitic minerals that are subject to expansion and contraction cycles according to the variation of humidity, which is the driving force of its formation. They occur commonly associated with lowlands with water seasonal accumulation in Vertisols. Due to the lack of specific literature about Gilgais in Brazilian territory, studies aimed at understanding it become necessary. Thus, the purpose of the present study is to present a morphometric and granulometric characterization of Gilgai microreliefs, looking to understand the distribution patterns of shapes and their granulometric fractions. Sampling was carried out in the Caicó (RN) region, at two sampling sites with soils of different textural compositions. The measurement of height, width, and distance between micromounds was performed in 60 samples per sampling site, totaling 120 measurements. For granulometric analysis, 24 samples were collected in each sampling site, which 12 correspond to the microhills and 12 to the depressions of the Gilgais. The data obtained were submitted to statistical tests (ANOVA and Mann-Whitney) to identify significant differences between sampling sites and between microrelief features. It was verified the presence of distinct distributions of height, width and distance measurements between micromounds for the study areas, as well as granulometric segregation patterns between the Gilgais features, occurring variations in short distances. The characterization indicated a silt and clay predominance in the micromounds and coarse fractions (pebble and gravel) and sand in the depressions. Larger micromounds were found at the sampling site with silty soils, recording the presence of Gilgai at an environment without the necessary requirements for identifying vertic horizon (Vertissolos). In the clayey sampling site, smaller micromounds and a higher density of individuals were observed. The correlations between the micromounds data to the sand fraction suggest this attribute as a limiting factor for vertical development, and the fine fraction (silt and clay) as an influencer in higher micromounds height measurements. The analysis also suggests a correlation between the distance between micromounds and the clay and silt fractions. The present study discards the hypothesis of homogeneity between Gilgai microreliefs in the studied region and identifies patterns of textural segregation on the surface.Attribution-NonCommercial-NoDerivs 3.0 Brazilhttp://creativecommons.org/licenses/by-nc-nd/3.0/br/PedologiaPadrões superficiaisSolos do semiáridoArgilominerais expansivosMorfologia de microrrelevosPedologySuperficial patternsSemiarid soilsExpansive claysPadrões superficiais - PedologiaPedologia - GeografiabachelorThesis