Banca de QUALIFICAÇÃO: RAISSA CAVALCANTE PINTO

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : RAISSA CAVALCANTE PINTO
DATE: 11/04/2023
TIME: 14:00
LOCAL: Remoto através de plataforma google meet
TITLE:

Meiofauna as an environmental quality indicator at polluted sandy beaches: influence of contaminated pluvial discharge. 

KEY WORDS:

sewage, fecal coliforms, nematodes, pollution

PAGES: 58
BIG AREA: Ciências Biológicas
AREA: Ecologia
SUBÁREA: Ecologia Aplicada
SUMMARY:

The pollution of sandy beaches caused by sewage disposal generates socioeconomic and environmental damage, altering the local biota. These changes serve to diagnose impacts on the environment, and the meiofauna is an ecological group that works as an indicator of environmental quality. In this work, we intend to determine how the meiofauna has the structure of the community affected on sandy beaches by the discharge of sewage, through rainwater popularly known as “dirty tongues”. The two studied beaches, R1 and R2, are located in the city of Maceió, Alagoas, Brazil. In each of them, sediment collections were carried out to identify meiofauna and microplastic in one of their foul tongues, in the intertidal region, in a gradient of 4 distances perpendicular to the foul tongue flow (0 m, 10 m, 50 m and 100 m) and in vertical strata of depth in the sediment (0-5 cm, 5-10 cm, 10-15 cm and 15-20 cm). Sediments were also collected for granulometric analysis and interstitial water for evaluation of inorganic nutrients and concentration of total coliforms and Escherichia coli. Physical-chemical parameters of the water were measured on site and criteria for defining the Beach Urbanization Index were evaluated. Univariate and multivariate tests were performed to compare community structure on different beaches, distances and vertical strata. The salinity was lower in the dirty tongues points. In R1, there was an increase in the percentage of finer sediments between the dirty tongue and the last distance gradient, while in R2 medium sands and a greater contribution of coarse sand were observed. In R2, the highest concentrations of ammonia, nitrate and nitrite were found, and in R1, the highest rates of fecal coliforms and Escherichia coli were found. Urbanization indices were similar, but it was higher in R1, which also had the highest abundance of microplastic. The highest abundance of meiofauna was found in R2, especially in the 50m and 100m distance gradients and in the most superficial layers of the sediment. Nematoda was the dominant group, followed by Gastropoda and Copepoda. The diversity values of the large groups of meiofauna showed significant differences for the interaction between the factors beaches and distances and distances and vertical strata, being very similar to the pattern found for equitability. The structure of the meiofauna community showed significant differences between beaches and between distances. The measured environmental parameters explained 91% of the variability in the structure of the meiofauna community, with salinity, pH, Eh and the abundance of total Coliforms and E. coli being the main factors responsible for the variation in the meiofauna. The results found indicate a severe degree of pollution on the studied beaches.

BANKING MEMBERS:
Presidente - 1544255 - TACIANA KRAMER DE OLIVEIRA PINTO
Interno(a) - 2024367 - MELISSA FONTES LANDELL
Externo(a) à Instituição - MAIKON DI DOMINICO - UFPR
Externo(a) à Instituição - ANDRE MORGADO ESTEVES