Banca de QUALIFICAÇÃO: MARIA NEYRA GONÇALVES DE BRITO

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : MARIA NEYRA GONÇALVES DE BRITO
DATA : 16/10/2022
HORA: 14:00
LOCAL: UNENAT, NOVA XAVANTINA
TÍTULO:

Effects of environment and fire on the phenology of Cerrado woody plants at different time scales

PALAVRAS-CHAVES:

Fenologia, mudanças climáticas, efeito do fogo

PÁGINAS: 101
GRANDE ÁREA: Ciências Biológicas
ÁREA: Ecologia
SUBÁREA: Ecologia de Ecossistemas
RESUMO:

In this study we aimed to evaluate the effect of climate, soil moisture and fire on the phenology of Cerrado woody species in short and long time scales. Observations of phenological events were made at biweekly intervals over two distinct time periods: period 1 from May 2008 to October 2011 and period 2 from May 2020 to February 2022. We sampled two adjacent sites of savanna formation of the Cerrado biome (cerrado stricto sensu). One site has been protected from fire since 2001 (unburned site) and the other was burned in (September 2001 and 2008 in August 2016), (burned site). We evaluated the vegetative (canopy foliage cover, budding, leaf abscission, young, adult and senescent leaves) and reproductive (production of floral buds, flowers, immature fruits and mature fruits) phenophases of the species at the two sites. At the unburned site only, we analyzed relative soil moisture at three depths (0-20 cm; 40-60 cm; and 90-110 cm). We show that the climate was markedly seasonal, but with higher rainfall volumes between 2009 and 2015 and lower between 2016 and 2021. The proportion of water in soils in the dry period of 2021 was lower than that recorded in 2020. The degree of leaf deciduousness varied widely among the species studied at the two sites. Among the 12 species sampled at both sites, the effects of fire were more evident on leaf cover in the canopies of evergreen plants relative to deciduous species. After fire, some species did not flower until one or two years at the burned site, others flowered but did not fruit, and some species did not mature fruit. When we compared the flowering of the species between the first period (wetter) and the second period (drier), we showed that nine species of the 12 showed a difference in the average time of flowering of the plants, of which eight species delayed and only one (Byrsonima pachyphylla) anticipated flowering in the second period compared to the first. Our results suggest that vegetative and reproductive phenological behaviors are affected by climate, water and fire, but the effect of fire on phenology depends on the degree of deciduousness of the plants.

MEMBROS DA BANCA:
Presidente - 132029001 - EDDIE LENZA DE OLIVEIRA
Interno - 019.811.331-51 - LETÍCIA GOMES DA SILVA - UnB
Externo à Instituição - Ana Clara Abadia Rodrigues de Sousa - UNEMAT
Externo à Instituição - LEONARDO MARACAHIPES DOS SANTOS - IPAM