Banca de DEFESA: EDIMÉIA LAURA SOUZA DA SILVA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : EDIMÉIA LAURA SOUZA DA SILVA
DATA : 18/03/2024
HORA: 09:00
LOCAL: Online transmitido via Google Meet - Nova Xavantina - MT
TÍTULO:

 "POTENTIAL FOR PHOTOSYNTHETIC ACCLIMATATION AND RESPIRATION OF SEEDLINGS OF FOREST SPECIES FROM THE SOUTHERN EDGE OF THE AMAZON"

PALAVRAS-CHAVES:

carbon absorption, climate change, seasonality, temperature.

PÁGINAS: 37
GRANDE ÁREA: Ciências Biológicas
ÁREA: Ecologia
RESUMO:

In recent years, the effects of climate change on Amazonian forests are intensifying and
promoting an increase in temperature, water stress and the frequency and intensity of
droughts. Therefore, the capacity for photosynthetic acclimatization and leaf respiration
will be of great importance for plants in this region, as, through these processes, plants
can maintain carbon absorption at high temperatures. Our objective was to evaluate the
potential for thermal acclimatization in the processes of photosynthesis and leaf
respiration in the dark of two important tree species widely distributed in the forests of
the southern edge of the Amazon; Hymenaea courbaril and Protium altissimum. Our
experiment was carried out in two air-conditioned greenhouses, the first operating at
room temperature and the second operating at an increased maximum daily temperature
of +1.5°C and +2.5°C. We measured the temperature response of net photosynthesis,

dark-adapted leaf respiration for the two species in three measurement cycles (pre-
treatment, +1.5°C and +2.5°C). Overall, our results show that photosynthetic and leaf

respiration parameters in the dark do not present clear evidence of acclimation in
relation to different temperatures, as the temperature response occurs in a similar way
between greenhouses. However, we observed some variations in photosynthesis and
leaf respiration responses between cycles for the two species, which tend to provide
some evidence for a seasonal adjustment in the species' thermal sensitivity in relation to
the region's natural temperature variation. Concluding that, despite not showing
acclimatization to the increase in maximum daily temperatures, the species can present
important strategies, such as seasonal adjustments, to deal with the region's temperature
variation and reduce carbon loss during the warmer seasons. But it is still not clear
whether the species would present the same strategies when faced with increased
temperature and water deficit simultaneously, as normally happens during the dry
season.

MEMBROS DA BANCA:
Interno - 82328201 - BEATRIZ SCHWANTES MARIMON
Presidente - 606.226.102-44 - DAVID ROBERTO GALBRAITH - LEEDS
Externo à Instituição - 704.952.111-68 - MARINA CORRÊA SCALON - UFPR