Banca de QUALIFICAÇÃO: CARLA HELOISA LUZ DE OLIVEIRA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : CARLA HELOISA LUZ DE OLIVEIRA
DATA : 24/12/2023
HORA: 09:30
LOCAL: REMOTO
TÍTULO:

High temperature amplifies drought stress in southern Amazon tropical trees

PALAVRAS-CHAVES:

High temperatures, drought, greenhouse, Amazon Forest

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). High temperature acceleration of drought-induced mortality occurred in all species evaluated, despite species-level variation in specific physiological responses to drought (e.g. some species exhibited faster declines in gs and Φ), we didn't find difference when we added heat in this same parameters in control greenhouse and also in arming greenhouse. 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 - ED
Interno - 555.911.591-68 - PAULO SERGIO MORANDI - UNEMAT
Externo à Instituição - TOMAS FERREIRA DOMINGUES - USP