Banca de DEFESA: FRANCES MARQUES MOREIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : FRANCES MARQUES MOREIRA
DATE: 25/02/2026
TIME: 09:00
LOCAL: Defesa on line
TITLE:

Soil quality indicators in areas with different land use and occupation systems in São Francisco do Itabapoana, RJ.

KEY WORDS:

Soil quality; Atlantic Forest; Multivariate Analysis.

PAGES: 50
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Ciência do Solo
SPECIALTY: Manejo e Conservação do Solo
SUMMARY:

The conversion of natural ecosystems into agricultural systems, when carried out without conservation planning, can compromise soil functionality and reduce its capacity to provide ecosystem services. In the Northern region of Rio de Janeiro state, coastal tableland soils naturally present physical and chemical limitations, which are often exacerbated by inadequate management practices. In this context, the present study aimed to select physical, chemical, and biological properties sensitive to land use changes to act as Soil Quality Indicators (SQI), allowing the identification and comparison of changes promoted by different agricultural systems representative of the municipality of São Francisco do Itabapoana, RJ. Four land use systems were evaluated: a remnant of Semideciduous Seasonal Forest (FF), used as an ecological reference; cultivated pasture (PA); sugarcane monoculture (MC); and cassava monoculture (MM). Soil samples were collected at depths of 0.00–0.10 m, 0.10–0.20 m, and 0.20–0.40 m, totaling 29 analyzed attributes. Data were subjected to univariate analyses (LSD test and Kruskal-Wallis), Pearson's linear correlation, and multivariate analyses (Principal Component Analysis and Hierarchical Cluster Analysis). Eighteen SQIs were identified, of which the most relevant — as they reflected impacts in two or more soil layers — were: base saturation (V%), potential acidity (H+Al), exchangeable aluminum (Al³⁺), fine sand (FS), exchangeable potassium (K⁺), and total organic carbon (TOC). The FF area showed positive association with most SQIs, standing out as a reference for healthy and self-sustaining soil. Among the agricultural systems, PA presented the greatest degradation, with low nutrient contents, CEC, and carbon stocks; MM occupied an intermediate position, with expressive carbon loss and absence of litter input; and MC showed the lowest degradation intensity, maintaining TOC, C stock, mineral-associated organic carbon (MAOC), and light organic matter (LOM) contents equivalent to those of FF in some layers. Multivariate analyses evidenced a clear separation between FF and agricultural areas, which were ordered along an increasing soil quality gradient: PA < MM < MC << FF. Dissimilarity was more pronounced in the surface layer (0.00–0.10 m), associated with differences in soil organic matter stocks and dynamics. It is concluded that native vegetation replacement significantly alters soil functionality down to 0.40 m depth, and that the selected SQIs present high potential to compose soil quality monitoring protocols under tropical conditions, supporting regenerative management practices and public policies aimed at soil conservation.

COMMITTEE MEMBERS:
Presidente - 1060711 - MARCOS GERVASIO PEREIRA
Externo ao Programa - 2136627 - NIVALDO SCHULTZ - UFRRJExterno à Instituição - JEFFERSON MATHEUS BARROS OZÓRIO - UEMS