Banca de QUALIFICAÇÃO: FRANCISCO ÉDER RODRIGUES DE OLIVEIRA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : FRANCISCO ÉDER RODRIGUES DE OLIVEIRA
DATA : 31/07/2025
HORA: 08:00
LOCAL: Sala de Aula do LASAPSA
TÍTULO:

1) DROUGHTS, LIVESTOCK EXPANSION, AND FOREST DEGRADATION: A 37-YEAR ASSESSMENT OF LANDSCAPE CHANGE IN A SEMIARID MUNICIPALITY OF BRAZIL2)LAND USE AND SUSTAINABLE DEVELOPMENT GOALS (SDGS) IN THE BRAZILIAN SEMIARID REGION: IMPACTS ON ORGANIC MATTER FRACTIONS, ENZYMATIC ACTIVITY, SOIL FERTILITY, AND MICROMORPHOMETRY

PALAVRAS-CHAVES:

1) Climate change; Forest fragmentation; Agriculture; Pasture
2) Carbon pools; microbial biomass; particulate organic carbon; cropping systems; pastures.

PÁGINAS: 32
RESUMO:

1) ABSTRACTClimate change has intensified extreme events, such as prolonged droughts in semiarid regions, with severe socioeconomic impacts, particularly in economies dependent on agriculture. In this context, we examined the effects of climate variability on productive and environmental dimensions in Iguatu (Ceará), a representative municipality of the Brazilian semiarid region, over a 37-year period (1985–2023). Our results confirm the intensification of droughts, reduction in water bodies, and decline in agricultural production, contributing to rural exodus and unregulated urban growth. In contrast, livestock farming, particularly cattle and sheep, expanded significantly, increasing pasture areas to 42% of the municipality by 2023. The lack of significant correlation between most agricultural production series and climate descriptors may indicate the role of factors including irrigation, government subsidies, and management practices, which enhance production resilience to climate variability. Meanwhile, forest cover was severely reduced and heavily fragmented. Our findings underscore the critical environmental degradation in the region and emphasize the importance of integrated strategies to mitigate climate change impacts. We recommend reforestation on rural properties combined with sustainable agricultural practices, such as intensive livestock farming, pasture rotation and fallow periods, reduction in slaughter age, and crop-livestock-forest integration. These measures have the potential to strengthen the resilience of the Brazilian semiarid region, promoting natural resource conservation and supporting local economic sustainability.

2) ABSTRACTThe intensification of land use, combined with the global imperative to meet the Sustainable Development Goals (SDGs) by 2030, has raised serious concerns about soil quality degradation in Brazil’s semiarid region. This study assessed the impacts of different land use systems on soil organic matter fractions, enzymatic activity, fertility attributes, and micromorphological structure in agricultural and livestock landscapes in Iguatu, Ceará, Brazil. Eight land use systems were evaluated: corn-bean consortium (CBC), corn monoculture (CORN), banana cultivation (BAN), guava-horticulture consortium (GHC), pasture with Urochloa mosambicensis under dairy cattle grazing (PB), cut-and-carry pasture with Cenchrus purpureus (PC), agroforestry system (AFS), and preserved native forest (Caatinga) as a reference. Soil samples were collected at 0–10 cm and 10–20 cm depths and analyzed for labile, recalcitrant, and biological carbon fractions, enzymatic activities (β-glucosidase and arylsulfatase), and chemical attributes. The findings indicated substantial losses in total organic carbon, reaching up to –75%, and a decline in enzymatic activity within systems characterized by continuous cultivation and limited diversification, such as CORN, GHC, and BAN. Conversely, CBC and PB systems, distinguished by their elevated clay content and organic residue return, demonstrated enhanced edaphic stability, manifesting reduced carbon losses and augmented accumulation of both active and stable organic fractions. Multivariate analyses (PCA, correlation, and clustering) revealed the multifunctionality of these systems, a finding that was further substantiated by micromorphological evidence of enhanced root presence and biological aggregation. This study provides substantial evidence that diversified agricultural practices, augmented by organic residue inputs and soil structure conservation, are imperative in mitigating soil degradation, enhancing carbon sequestration, and achieving Sustainable Development Goals 2, 13, and 15 in the context of escalating global aridity

MEMBROS DA BANCA:
Externa à Instituição - DIANA FERREIRA DE FREITAS - UFC
Presidente - 1780797 - EULENE FRANCISCO DA SILVA
Interna - 1851841 - JEANE CRUZ PORTELA
Interno - 1753199 - RAFAEL OLIVEIRA BATISTA