Banca de DEFESA: CARLA HELOISA LUZ DE OLIVEIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : CARLA HELOISA LUZ DE OLIVEIRA
DATA : 22/03/2024
HORA: 09:30
LOCAL: Online transmitido via Google Meet - Nova Xavantina - MT
TÍTULO:

Increase on air temperature amplify the effect of water stress on south Amazon trees species

PALAVRAS-CHAVES:

High temperatures, water availability, greenhouse

PÁGINAS: 29
GRANDE ÁREA: Ciências Biológicas
ÁREA: Ecologia
RESUMO:

Increasing heat, vapour pressure deficit and decreasing water availability are major climate
stressors facing tropical forests. High temperatures and long periods of drought expose plants
to stressful conditions, possibly bringing them closer to their physiological thresholds, but little
is known about their interactive effects on tropical plant functioning. Understanding these
interactions is particularly critical in the Southern Amazon, where temperatures are increasing
faster and there are stronger drying trends than other Amazon regions. Through greenhouse
experiments in Southern Amazonia, we show that moderate increases in temperature (+3°C) in
the absence of water stress have little impact on the physiological function of three
representative Southern Amazonian plant species. On the other hand, when combined with
drought stress, higher temperatures accelerated mortality and accentuated drought-induced
reductions in stomatal conductance (gs) and photosynthetic quantum yield (Φ). The
acceleration of mortality induced by drought at high temperatures occurred in the three species
evaluated, despite species-level variation in specific physiological responses to drought (e.g.
some species exhibited faster declines in gs and Φ), We found no difference in these same
parameters in the control house, or when we added heat to the heated house. Our results suggest
that the high rates of temperature increase observed in the Southern Amazon, coupled with the
lengthening of the dry season, is likely to elevate tree mortality and substantially impact forest
dynamics in this region.

MEMBROS DA BANCA:
Presidente - 606.226.102-44 - DAVID ROBERTO GALBRAITH - LEEDS
Externo à Instituição - TOMAS FERREIRA DOMINGUES - USP
Externo à Instituição - 027.832.941-17 - WESLEY JONATAR ALVES DA CRUZ - SEDUC - MT