Banca de QUALIFICAÇÃO: ÍCARO GUEDES DA SILVA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : ÍCARO GUEDES DA SILVA
DATE: 07/08/2025
TIME: 14:00
LOCAL: Google Meet
TITLE:

SOIL-RELIEF-VEGETATION RELATIONSHIP IN ALTITUDINAL GRADIENTS IN A MOUNTAIN ENVIRONMENT IN THE BRAZILIAN SEMI-ARID REGION

KEY WORDS:

Escarpments, Morphogenesis, Caatinga.

PAGES: 55
BIG AREA: Ciências Humanas
AREA: Geografia
SUMMARY:

The Caatinga is a biome marked by water stress, with prolonged periods of drought, which implies a very dynamic and seasonal vegetation. The vegetation of the Caatinga has distinct phytophysiognomies, which are sometimes influenced by the relief and soils distributed from different altitude levels. The objective of this study was to analyze the soil-relief vegetation relationship in altitudinal gradients in the Brazilian semiarid region, having more specifically as the study area the Serra do Lima, in the municipality of Patu-RN. Bibliographic surveys were carried out, and thematic maps (geology, geomorphology, soils, vegetation, use and occupation) were produced in a GIS environment using the QGIS software. Finally, fieldwork was carried out, with soil collections and morphological descriptions in different compartments of the landscape. The geology of the area is predominantly associated with the Itaporanga Suite, which is marked by the occurrence of granites. A small part of the area also has rocks from the São João do Sabugi Intrusive Suite. The granites vary from fine to coarse, with occurrences of porphyry granites. The color varies from light gray to pink, and is of Precambrian age. The Serra do Lima has an altimetric variation between 166 m and 650 m. The summit surfaces have convex tops and are semicircular, with higher altitude in the northern sector. The study area has four relief units, namely: i) escarpments; ii) rocky outcrops; iii) mountain range; iv) sertaneja surface II. The escarpments border the entire mountain range and are associated with rocky outcrops. At the foot, there are talus slopes associated with open shrub vegetation on shallow and poorly developed soils. The rocky outcrops are sometimes on the summit surfaces, and are concentrated in the northern and southwest sectors of the area. In turn, the sertaneja surface is concentrated in the southwest sector. The area is predominantly composed of Eutrophic Litholic Neossolos (RLe) and a small area with the occurrence of Eutrophic Red Argisols (PVe), especially in the extreme southwest. The occurrence of poorly developed and shallow soils, such as RLe, is directly associated with the extremely weather-resistant parent material (granite) and the erosion processes that promote constant rejuvenation of the soils in the mountainous areas. In turn, it is suggested that the occurrence of PVe is associated with the occurrence of a more mafic parent material, at the foot of the mountainous area, in the extreme west of the study area. The Serra do Lima has a predominance of forested steppe savannah, which covers approximately 94% of the area, equivalent to 21.657 km2. In turn, the wooded steppe savannah corresponds to 3% of the area and agriculture accounts for the remaining 3%. This research offers contributions to the understanding of landscapes in semi-arid mountain environments, and this type of study is increasingly relevant in the face of climate change, in which temperatures in some sectors of the landscape can directly influence species of flora and fauna. In this context, mountain environments can become even more special areas, as refuges for several species.

COMMITTEE MEMBERS:
Interno - 3289864 - ABNER MONTEIRO NUNES CORDEIRO
Presidente - 1997952 - DAVI DO VALE LOPES
Externo à Instituição - DEMÉTRIO ANGELO LAMA ISMINIO
Interno - 1112649 - JOSE YURE GOMES DOS SANTOS