Banca de QUALIFICAÇÃO: TAYNÃ FERNANDES NUNES

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : TAYNÃ FERNANDES NUNES
DATA : 06/08/2021
HORA: 14:00
LOCAL: Nova Xavantina, Online
TÍTULO:

Assessing tree water stress of species from a Amazonia-Cerrado transitional forest

PALAVRAS-CHAVES:

Forest, tropical, ecophysiology, trees, functional traits, Amazonia, Cerrado, tree mortality

PÁGINAS: 35
GRANDE ÁREA: Ciências Biológicas
ÁREA: Ecologia
SUBÁREA: Ecologia de Ecossistemas
RESUMO:

The increase in the frequency and intensity of severe droughts can change the structure, productivity and composition of forests by increasing tree mortality rates. Therefore, hydraulic characteristics are fundamental traits to predict potential effects of how climate change may affect forest dynamics. We explore here the variation in stomatal regulation and water vulnerability (P50) and associate these characteristics with the vital rates of tree species in a Cerrado-Amazon transition forest, where water stress is more accentuated. The general objectives of the study were to quantify stomatal regulation strategies in a transitional forest between the Amazon and the Cerrado and to define ecophysiological thresholds that indicate the water vulnerability of different species in the region. The following hypotheses were tested: (i) Tanguro tree species do not fully open their stomata during the day; (ii) the trees in these environments have a hydraulic pathway that is too resistant to embolism; (iii) trees that do not regulate water loss during the day (leave the stomata open) are more likely to die during droughts. We found that: (i) there was low stomatal regulation among species, but that some species manage to reach a high range of mean values of leaf water potential (Ψf); (ii) the average loss of conductivity value (P50) was no less negative than other Amazonian forests; (iii) Resistance to cavitation was positively related to the mortality rate. These results suggest that tree species at Tanguro have different ecological strategies to deal with environmental water stress.

MEMBROS DA BANCA:
Presidente - 220.974.038-08 - PAULO MONTEIRO BRANDO - NENHUMA
Interno - 996.005.011-49 - DIVINO VICENTE SILVÉRIO - UnB
Interno - 986.188.651-68 - SIMONE MATIAS DE ALMEIDA REIS - UNEMAT
Externo à Instituição - ANTONIO CARLOS SILVEIRO DA SILVA - IPAM