Banca de QUALIFICAÇÃO: ARTURO VARELA OCON

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE: ARTURO VARELA OCON
DATA: 25/06/2026
HORA: 14:00
LOCAL: Online
TÍTULO:

Beyond pH correction: complementary effects of biochar and lime on highly weathered acidic tropical soils

PALAVRAS-CHAVES:

Soil acidity. Biochar. Liming. Highly weathered tropical soils. Soil amendments.

PÁGINAS: 20
GRANDE ÁREA: Ciências Agrárias
ÁREA: Agronomia
SUBÁREA: Ciência do Solo
ESPECIALIDADE: Fertilidade do Solo e Adubação
RESUMO:

Highly weathered acidic tropical soils are characterized by multiple interacting chemical constraints, including aluminum (Al) toxicity, phosphorus (P) fixation, low base saturation, and low cation exchange capacity (CEC). In these soils, acidity is increasingly recognized as a multidimensional functional problem rather than simply a low-pH condition, since pH alone does not fully represent soil chemical functionality or nutrient availability. In Brazil, liming has been the foundation of acidic soil management due to its low cost, effectiveness in increasing soil pH, and ability to reduce exchangeable acidity. However, several acidity-related limitations may persist even after conventional pH correction. In this context, biochar has gained increasing attention not as a substitute for lime, but as a potential complementary amendment capable of modifying soil chemical properties to correct acidic soils through mechanisms that differ from those of conventional liming. However, biochar effects are strongly dependent on feedstock properties, application rates, and soil conditions, and many studies reporting strong responses rely on high biochar rates (commonly 10–40 t ha⁻¹ or 2–5% w/w) that may not be agronomically or economically realistic under tropical agricultural systems. To evaluate the complementary effects of liming and contrasting biochars on key acidity-related soil chemical properties under agronomically realistic biochar application rates, two contrasting tropical soils will be incubated for 90 days under combinations of four lime rates (0, 50, 75, and 100% of the estimated lime requirement) and two contrasting biochars applied at rates equivalent to 5 and 10 t ha⁻¹. Using a completely randomized factorial design with four replicates (160 experimental units), the study will assess how combined lime–biochar applications modify key acidity-related soil chemical properties, particularly pH, exchangeable acidity, CEC, buffering capacity, exchangeable base cations (Ca, Mg, K, and Na), base saturation, aluminum saturation, and P availability. Results are expected to improve understanding of how contrasting biochars interact under conventional liming conditions and which acidity-related soil properties are most responsive to combined amendment strategies in highly weathered tropical soils.

MEMBROS DA BANCA:
Externo à Instituição - RAFAEL DA SILVA TEIXEIRA - UFV (Membro)
Presidente - LEONIDAS CARRIJO AZEVEDO MELO (Membro)
Externo à Instituição - EVANISE SILVA PENIDO - ITV (Suplente)
Interno - BRUNO TEIXEIRA RIBEIRO (Membro)