Banca de QUALIFICAÇÃO: DANIEL FELIPE DA SILVA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : DANIEL FELIPE DA SILVA
DATE: 05/09/2025
TIME: 09:00
LOCAL: Laboratório de Informática, NE-Clim
TITLE:

CO₂ Exchange Dynamics in the Caatinga Biome: An Analysis of Source or Sink Conditions Under the Influence of Biophysical Factors

KEY WORDS:

Caatinga, SDTF, Semi-arid, Random Forest, Eddy Covariance, Carbon Balance

PAGES: 35
BIG AREA: Ciências Exatas e da Terra
AREA: Geociências
SUBÁREA: Meteorologia
SPECIALTY: Micrometeorologia
SUMMARY:

Semi-arid forests play a crucial role in the global carbon cycle, standing out for their efficiency in CO₂ use and their influence on the variability of terrestrial carbon sinks. The Caatinga, classified as a seasonally dry tropical forest, is recognized as an efficient carbon sink, making it essential to understand the biophysical factors that regulate its gas exchanges in the face of future climate change scenarios. Precipitation is considered the main driver of CO₂ exchange seasonality in this biome, although climatic, edaphic, and vegetation functional variables also exert significant influence. This study aims to investigate how biophysical factors control the CO₂ exchanges that determine whether the Caatinga acts as a carbon source or sink, using data collected at the Açu National Forest (Flona de Açu). Measurements were obtained from a flux tower equipped with an Eddy Covariance system and auxiliary instruments to monitor variables such as photosynthetically active radiation, air and soil temperature, vapor pressure deficit, atmospheric CO₂ concentration, and soil moisture. The influence of these factors on the components of the carbon balance—GPP, Reco, and NEE—will be analyzed using the Random Forest algorithm and three-dimensional dispersion analyses. Preliminary results indicate that, during the first year of monitoring, sensible heat flux predominated over latent heat flux, reflecting the region’s water scarcity. Nevertheless, the Caatinga remained a CO₂ sink, reinforcing its relevance in the biogeochemical carbon cycle.

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Interno - 2086472 - BERGSON GUEDES BEZERRA
Interna - ***.425.702-** - KEILA RÊGO MENDES - UFPE
Interno - 3217859 - PEDRO RODRIGUES MUTTI
Externo ao Programa - ***.049.108-** - LUIS MARCELO DE MATTOS ZERI - USP