Banca de DEFESA: JOHN JAIRO AREVALO HERNANDEZ

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE: JOHN JAIRO AREVALO HERNANDEZ
DATA: 15/04/2025
HORA: 08:00
LOCAL: DCS02
TÍTULO:

MACRO AND MICROPLASTICS IN THE SOIL: ABUNDANCE, CHARACTERIZATION, IDENTIFICATION, AND INTERACTIONS UNDER DIFFERENT LAND USES IN AN AGRICULTURAL SUB-BASIN

PALAVRAS-CHAVES:

diffuse pollution, land use, polymers, spatial distribution, soil attributes, tropical soil.

PÁGINAS: 90
GRANDE ÁREA: Ciências Agrárias
ÁREA: Agronomia
SUBÁREA: Ciência do Solo
ESPECIALIDADE: Manejo e Conservação do Solo
RESUMO:

Plastic waste is a significant environmental issue, with poor agricultural waste management contributing to soil pollution and affecting agroecosystems. This study investigated macroplastics (MaP, >25 mm), mesoplastics (MeP, 5–25 mm), and microplastics (MP, <5 mm) across agricultural, pasture, and forest soils in a micro-watershed of the Upper Rio Grande in Lavras, Minas Gerais, Brazil. The first study evaluated microplastic recovery in tropical soils using density separation with three solutions, achieving 81.0%–98.8% recovery for low-density polyethylene (LDPE) and 59.7%–75.2% for polyvinyl chloride (PVC). The second study mapped MaP and MeP, identifying polypropylene (40.94%), polyethylene (30.20%), and PVC (11.41%), with abundances ranging from 0.509 × 10³ to 104 × 10³ pieces ha⁻¹ and mass from 0.039 to 405 kg ha⁻¹. Plastic debris correlated with slope, the LS factor, and vegetation cover. The third study analyzed MP in the 0–20 cm soil layer, identifying polypropylene, polyethylene, PET, and PVC in films and fragments. Agricultural, forest, and pasture soils showed average MP abundances of 3,406, 3,826, and 2,553 pieces kg⁻¹, respectively. MP abundance negatively correlated with organic matter, clay, and porosity, and positively with topographic attributes. The fourth study used geostatistical analysis to predict MP spatial distribution, showing strong spatial dependence and higher concentrations in agricultural and forest soils. These results reveal plastic pollution hotspots and emphasize the need for improved waste management strategies to reduce plastic contamination in tropical agroecosystems.

MEMBROS DA BANCA:
Interno - YURI LOPES ZINN (Membro)
Presidente - MARX LEANDRO NAVES SILVA - UFLA (Membro)
Interno - JUNIOR CESAR AVANZI (Membro)
Externo à Instituição - ELOANA JANICE BONFLEUR - UFPR (Membro)
Externo ao Programa - CAMILA SILVA FRANCO - DAM/EENG (Suplente)
Externo à Instituição - BERNARDO MOREIRA CÂNDIDO - MIZZOU (Suplente)
Externo ao Programa - ALESSANDRA ANGELICA DE PADUA BUENO - DEC/ICN (Membro)