Banca de QUALIFICAÇÃO: MARIA LENICE VENTURA DINIZ
Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.DISCENTE : MARIA LENICE VENTURA DINIZ
DATA : 31/10/2016
HORA: 14:00
LOCAL: Departamento de Ecologia da UFRN
TÍTULO:
Stoichiometric regulation of planktonic bacteria in different trophic states of freshwater ecosystems
PALAVRAS-CHAVES:
freshwater environments, bacteria, stoichiometry, nutrients, homeostasis, flexibility, trophic state
PÁGINAS: 50
GRANDE ÁREA: Ciências Biológicas
ÁREA: Ecologia
RESUMO:
The dynamics of aquatic ecosystems is changes in the stocks and flows over time, and all these processes are mediated by abiotic factors along with living organisms (Andrade & Romeiro, 2009). Bacteria are organisms with higher biomass in the biosphere and are essential to the functioning of lake ecosystems (Lindström, 2001; MacCord et al., 2013). The dynamics of these environments is deeply affected by the interactions between microorganisms. The rates which bacteria recycle nutrients are related to their availability (quantity and quality) in the environment, as well as the demand (requirement) of microorganisms (Cotner & Biddanda, 2002). Some factors may regulate bacterial metabolism and biomass, as the availability of nutrients related to the concentration and balance (stoichiometry) of carbon (C), nitrogen (N) and phosphorus (P) (Pace & Cole, 1994, 1996; Vrede, 2005; Carlsson et al., 2012; Rejas et al., 2005; Fonte et al., 2011). Aquatic ecosystems have variations in the composition of its nutrients, and this should affect the metabolism of the bacteria. Homeostasis is the ability of organisms maintain their chemical composition independent of the chemical changes in the environment and its resources; organisms with low homeostatic capacity, or flexible, have their chemical composition strongly influenced by the concentrations of the elements available in the environment (Sterner & Elser, 2002). Because of the large variation stoichiometric that bacteria have, trophic state characteristics of an environment and availability of nutrients in an ecosystem add factors that regulate the homeostatic or flexible behavior of these organisms. Aquatic ecosystems in the tropical region have higher temperature and luminosity compared to other regions of the World (Lewis Jr., 1995). These conditions are metabolically favorable to the growth of organisms, on the other hand, it has been reported high ratio C: N: P ratios in the low latitude regions (Das, 2014). Our hypothesis is that the trophic state determines whether the bacterial communities behave homeostatic or flexible in low-latitude environments. Our goal is to evaluate the response of these communities (stoichiometric control) to different availability of nutrients in these environments.
MEMBROS DA BANCA:
Interno - 1714892 - ADRIANO CALIMAN FERREIRA DA SILVA
Presidente - 1639731 - ANDRE MEGALI AMADO
Externo ao Programa - 1434166 - LUCIANA SILVA CARNEIRO
Externo ao Programa - 048.880.204-00 - NG HAIG THEY - FURG