Banca de DEFESA: TACIANA DA SILVA PARAIZO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : TACIANA DA SILVA PARAIZO
DATE: 27/06/2025
TIME: 07:00
LOCAL: UFRPE
TITLE:

Improvement of the physical and microbiological attributes of soil cultivated with eucalyptus

KEY WORDS:

Degraded areas; Glomalin; Aggregate stability; Carbon stock

PAGES: 55
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Ciência do Solo
SPECIALTY: Manejo e Conservação do Solo
SUMMARY:

The emergence of degraded areas is a complex process involving the deterioration of soil attributes, resulting in undesirable changes in its physical, chemical, and biological properties. Eucalyptus cultivation emerges as a means of enhancing and restoring these areas, mainly due to its fast growth characteristics and low nutritional requirements. The study hypotheses are: (i) The duration of eucalyptus cultivation positively influences the greater distribution of large and extra-large macroaggregates in the soil; (ii) Microbiological activity is positively influenced by the duration of eucalyptus cultivation. This study aimed to evaluate the effect of the duration of eucalyptus cultivation on the improvement of the physical and microbiological attributes of soils cultivated with eucalyptus. Samples were collected to analyze physical and microbiological attributes at a forestry-based company located in the metropolitan region of Maceió-AL Collections were conducted in areas with four different cultivation durations: three, six, nine, and eleven years. Additionally, soil samples from an area cultivated with sugarcane were collected for reference. In each area, samples were collected at depths of 0–10, 10–20, and 20–40 cm, including both disturbed and undisturbed samples. The chemical properties, organic carbon, and its stock in the soil were analyzed. Furthermore, the classification of aggregates and the carbon stocks within them were determined, along with microbial biomass carbon, basal respiration, metabolic and microbial quotient, glomalin abundance, and the activity of enzymes (β-glucosidase, arylsulfatase, and alkaline phosphatase). After only three years of eucalyptus planting, an increase in carbon stock in the soils was observed. Additionally, a greater quantity of extra-large macroaggregates was found after six years of cultivation in the surface layer, indicating an improvement in soil structure. In deeper layers, a higher quantity of extra-large macroaggregates under eleven years of cultivation suggests greater ecosystem stabilization. After three years of cultivation, there was a noticeable trend in enzymatic activity. The correlation between total glomalin and the proportional mass of large aggregates after eleven years of eucalyptus cultivation indicates a greater tendency for soil regeneration. The results of this study demonstrate that eucalyptus cultivation, even over relatively short periods, contributes significantly to the recovery of degraded soils, promoting the increase of total carbon stocks and their stabilization within macroaggregates, enhancing microbiota metabolic efficiency, and forming more stable physical structures. The simultaneous improvement of physical and microbiological attributes over time highlights the role of eucalyptus as a restorative agent, capable of triggering regenerative processes in the soil and strengthening its ecological resilience.

COMMITTEE MEMBERS:
Presidente - ADEMIR DE OLIVEIRA FERREIRA
Interno - ***.952.028-** - FELIPE JOSÉ CURY FRACETTO - USP
Externo ao Programa - 1013158 - RENISSON NEPONUCENO DE ARAUJO FILHO - UFRPE