masterThesis
Diversidade de fungos micorrízicos arbusculares (Glomeromycota) em ambientes aquáticos lênticos e lóticos do Rio Grande do Norte, Brasil
Fecha
2022-02-23Registro en:
QUEIROZ, Mariana Bessa de. Diversidade de fungos micorrízicos arbusculares (Glomeromycota) em ambientes aquáticos lênticos e lóticos do Rio Grande do Norte, Brasil. 2022. 96f. Dissertação (Mestrado em Sistemática e Evolução) - Centro de Biociências, Universidade Federal do Rio Grande do Norte, Natal, 2022.
Autor
Queiroz, Mariana Bessa de
Resumen
Arbuscular Mycorrhizal Fungi (AMF) are symbiotic microorganisms from terrestrial and
aquatic plant roots. However, lentic and lotic aquatic ecosystems are little explored regarding
their occurrence and ecology. Few diversity inventories have documented more than 100
species and ecological studies have tested the influence of environmental variables on the
degree of root colonisation, but the structure of AMF communities under these two conditions
and the influence of environmental variables is poorly known. This work objective was to
make an inventory of the AMF species in two lentic environments (Carcará and Arituba
Lagoons) and two lotic environments (Boa Cica Stream and Pium River) in the municipality
of Nísia Floresta, Rio Grande do Norte, Brazil, and evaluate the influence of water and
seasonal parameters on species composition, diversity, richness, and sporulation. For this
purpose, two samples were taken in the dry (December 2016) and wet (July 2017) periods,
removing rhizospheric soils of different species of macrophytes inhabiting depths from 0.02
to 2.72 m. Glomerospores were extracted from 50 g of soil and mounted on slides for
taxonomic identification. Species were evaluated for occurrence frequency and relative
abundance, being later classified as dominant, common, and rare. Differences in the species
composition were tested by Cluster Analysis, ANOSIM, and SIMPER. Diversity was
evaluated among different conditions and seasons using rarefaction curves interpolated and
extrapolated to Hill numbers. Richness and sporulation were tested in relation to conditions,
seasons, and depth by Generalized Linear Models and ANOVA. Eighty-eight species were
identified and classified in 5 orders, 11 families, and 21 genera. Sixty-one species occurred in
the lentic condition (57 in the Arituba Lagoon and 24 in the Carcará Lagoon) and 55 in the
lotic condition (39 in the Boa Cica Stream and 31 in the Pium River). Seventeen species were
shared among the four sites. Glomeraceae and Acaulosporaceae were the most representative
families in species richness in all lentic and lotic interactions and species abundance in lotic
interactions, while the Ambisporaceae family showed high abundance in lentic interactions.
Species composition differed between lentic and lotic interactions. Greater Shannon and
Simpson diversity were found in the Arituba/Dry interaction to the detriment of lower
diversity in Boa Cica/Dry. Lotic interactions did not differ in species richness and
glomerospores density but were different from lentic interactions in species richness. The
lentic interactions, on the other hand, differentiate among themselves, in higher richness and
sporulation found in Arituba Lagoon, which also showed the highest nutrient concentration in
sediment. There was a decrease in richness and glomerospores density caused by a depth
gradient increase only in Arituba Lagoon; it is possibly related to a mesotrophic trait of this lagoon. This work results bespeak these aquatic ecosystems potencial in harboring high richness of AMF species and suggest that communities composition and species richness are influenced by lentic and lotic condition and also that richness and sporulation vary among lentic environments with different trophic status.