Banca de DEFESA: Josiane Santos Batista Carioca de Paula

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : Josiane Santos Batista Carioca de Paula
DATA : 22/03/2023
HORA: 08:00
LOCAL: Presencial - Projeto NEPBIO
TÍTULO:

IMPACT OF URBAN STREAM ON GREENHOUSE GAS EMISSIONS.

 

PALAVRAS-CHAVES:

KEYWORDS: Urban waters, Carbon dioxide, Aquatic macrophytes, Seasonality

PÁGINAS: 51
GRANDE ÁREA: Ciências Biológicas
ÁREA: Biologia Geral
RESUMO:

The study of greenhouse gases, in particular CO2, in inland waters has been fundamental to sum up the contribution of these environments in the global carbon balance. In this regard, urban waters composed of rivers or streams have served as potential points of emission of greenhouse gases. Therefore, this work aimed to analyze the impact of urban streams on CO2 emission by diffusive flow at the water-atmosphere interface. In the first chapter, research was carried out in four urban streams/channels, which flow into one of the main rivers of the Pantanal (Paraguay River). For this, we used a floating chamber on aquatic macrophytes and in an open water, considering the flow (emission and/or absorption of CO2). The collections were carried out in the wet season (February) and dry season (September) in the Pantanal. During the rainy season, the streams had between 5 and 40% of vegetation cover, while in the dry season it was 80 to 100%. The rainy season presented an emission about twice as high as in the dry season (5,180.64 ± 8,196.20 mg m-2 day-1 and 2,654.92 ± 7,190.64 mg m-2 day-1, respectively). Only in one of the analyzed streams, it was not possible to find absorption of CO2 by macrophytes, while the other three showed absorption by these plants. In the second chapter, the temporal dynamics of CO2 emission by diffusion flow at the water-atmosphere interface in an urban stream in the municipality of Cáceres, MT, Brazil, was studied, considering emissions in the open bed and on aquatic macrophytes over a period of time. 24-hour cycle, for nine months (October 2021 to June 2022). The chamber was used in open water and on macrophytes of the genus Pontederia sp. It was observed that the macrophytes showed absorption and/or emission of CO2, while the open bed showed only CO2 emission throughout the 24-hour cycle. The CO2 flux variation can change, depending on the observed time or the period of the year. The times of 9:00 am and 12:00 pm showed the highest peaks of CO2 absorption by macrophytes and the times of 6:00 pm and midnight showed the highest peaks of CO2 emission. Streams and/or urban channels are extremely neglected environments. We suggest that public policies are objective and practical for the resumption of these environments as important spaces for society, as well as for the reduction of the impacts of these environments in the contribution of greenhouse gases.

MEMBROS DA BANCA:
Presidente - 118188001 - ERNANDES SOBREIRA OLIVEIRA JUNIOR
Interno - 420.965.451-53 - CELIA ALVES DE SOUZA - UNEMAT
Interno - 118181008 - WILKINSON LOPES LAZARO
Externo à Instituição - BEATRIZ FERRAZ BUHLER - SEDUC - MT