Banca de DEFESA: LUCAS VINICIUS CAVALCANTE ESTEVES

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : LUCAS VINICIUS CAVALCANTE ESTEVES
DATE: 03/08/2023
TIME: 18:30
LOCAL: Google Meet
TITLE:

FUNCTIONAL LEAF TRAITS IN CONGENERIC SPECIES OF TREE COMMUNITIES IN AN EDAPHIC GRADIENT IN CENTRAL AMAZON

KEY WORDS:

Leaf anatomy, Amazon Domain, Rainforest, soil gradient, plant-soil relationships, Amazonian Savanna.

PAGES: 51
BIG AREA: Ciências Biológicas
AREA: Ecologia
SUMMARY:

Unprecedented environmental changes are altering the global climate and rates of plant biodiversity. It is predicted that as a result of these changes, forest formations may become more open in the future. The ability of plants to adjust or vary their functional attributes can determine the success of woody species in this scenario. The objective was to investigate possible variations in functional leaf traits of congeneric species of Tachigali and Pouteria in tree communities under different edaphic conditions in savanna and forest areas in the Central Amazon. For this purpose, completely expanded healthy leaves of woody congeneric species were collected in the Phytophysiognomies of Rainforest and Amazonian Savanna, both in the state of Pará, Brazil. In the field, intact leaves were stored in 70% ethanol for subsequent evaluation of hydraulic traits. For the analysis of anatomical (structural characterization, micromorphometry, and histochemistry) and morphological traits, the middle third of the leaf blade was selected, with samples fixed in FAA70 solution and stored in 70% ethanol. Subsequently, the samples were dehydrated in an increasing ethyl series, pre-infiltrated, infiltrated, and embedded in resin, cross-sectioned using a manual rotary microtome (5 μm), stained with toluidine blue, and mounted in acrylic varnish. Leaf structure observations and records were made using a photomicroscope. The results showed that congeneric species of Tachigali and Pouteria have significant variations in functional morphoanatomical leaf traits in the different studied phytophysiognomies, which likely aid in their growth and establishment. It was also observed that species present in the savanna environment, with lower nutrient availability, exhibited more conservative traits related to water storage and drought resistance. However, in the forest area species with higher nutrient availability, more acquisitive strategies were observed. The study suggests that variations in leaf traits are essential for the survival and development of tree species in each vegetation type, and that in savanna areas there is a clear degree of xeromorphism. Therefore, in both studied phytophysiognomies, the functional attributes of Tachigali and Pouteria may be responses to low soil nutrient content, water scarcity, and/or high solar radiation. In a scenario of global climate change, understanding the functional adjustments of these congeneric woody species can contribute to predicting the structure and assembly of plant communities.

COMMITTEE MEMBERS:
Externo à Instituição - ARLETE APARECIDA SOARES - UFC
Externo à Instituição - BRUNO HENRIQUE PIMENTEL ROSADO - UERJ
Interno - 2143267 - JOSE MAX BARBOSA DE OLIVEIRA JUNIOR
Externa à Instituição - NARAH COSTA VITARELLI