Banca de DEFESA: ANA LUIZA BEZERRA DA COSTA SARAIVA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : ANA LUIZA BEZERRA DA COSTA SARAIVA
DATE: 17/11/2025
TIME: 14:00
LOCAL: Google Meet - https://meet.google.com/ixs-rwsu-hdj
TITLE:

Carbon Flux and Ecosystem Service Regulation in Semi-Arid Areas of the Caatinga, Northeast Brazil

KEY WORDS:

Carbon cycle; Caatinga; semi-arid; regulation service in the Caatinga;
mitigation; carbon sink.ABSTRACT

 

PAGES: 131
BIG AREA: Ciências Humanas
AREA: Geografia
SUMMARY:

This study analyzed carbon flux in three preserved Caatinga areas located in the Brazilian
Semi-arid region: Serra Negra do Norte (RN), Serra Talhada (PE), and São João (PE).
The objective was to understand how annual climate variability influences carbon
dynamics and the mitigating potential of ecosystem regulation services.
Micrometeorological towers from the National Observatory of Water and Carbon
Dynamics in the Caatinga Biome (ONDACBC) were used to measure gross primary
production (GPP), ecosystem respiration (Reco), and net ecosystem exchange (NEE).
These data were integrated with climatic variables such as precipitation, solar radiation,
air temperature, relative humidity, and vapor pressure deficit (VPD). The results indicated
that, although the three sites present distinct geographic characteristics and annual
climatic rhythms, all acted as annual carbon sinks. In Serra Negra do Norte, the synchrony
between solar radiation and rainfall enhanced carbon uptake, resulting in the highest CO2
sequestration values (up to 25 tCO2 ha−1 year−1). Serra Talhada showed greater sensitivity
to climate variability, with temporary emission periods, but maintained a negative annual
NEE balance, functioning as a sink (XX tCO2 ha−1 year−1). São João stood out for its more
regular rainfall regime and milder temperatures, which favored net photosynthesis and
efficiency as a sink (17 tCO2 ha−1 year−1). Differences in capture magnitude among the
sites highlight that carbon flux dynamics are directly linked to the interaction between
climatic elements and environmental conditions. Even in years classified as dry, the
Caatinga demonstrated resilience, confirming its relevance as one of the most efficient
biomes for carbon sequestration among global semi-arid regions and within Brazil’s
natural domains.It is concluded that the Caatinga plays a strategic role in climate change
mitigation, offering an essential ecosystem service of atmospheric regulation. These
results reinforce the need for public policies aimed at conserving and restoring native
vegetation and promoting climate justice, as well as the implementation of payment for
ecosystem services programs that recognize the Semi-arid’s mitigating potential.

 

COMMITTEE MEMBERS:
Presidente - 2966354 - DIOGENES FELIX DA SILVA COSTA
Interno - 3263586 - FRANCISCO JABLINSKI CASTELHANO
Externo ao Programa - 2086472 - BERGSON GUEDES BEZERRA - UFRNExterno ao Programa - 1752417 - CLAUDIO MOISES SANTOS E SILVA - UFRNExterna à Instituição - KEILA RÊGO MENDES - INPA
Externo à Instituição - MAX WENDELL BATISTA DOS ANJOS - TU Berlin