ANA KAROLINE FERREIRA DOS SANTOS
AUTHOR: ANA KAROLINE FERREIRA DOS SANTOS
TITLE: ANALYSIS OF SPECTRAL BEHAVIOR OF WATER RESERVOIR OF BARRA DOS COQUEIROS (GO) UHE (ANÁLISE DO COMPORTAMENTO ESPECTRAL DAS ÁGUAS DO RESERVATÓRIO DA USINA HIDRELÉTRICA BARRA DOS COQUEIROS (GO))
ADVISOR: Prof. Dr. João Batista Pereira Cabral.
DEFENSE DATE: 08/20/2018
ABSTRACT:
The solar energy that reaches the earth's surface represents an essential phenomenon for maintenance of life and knowledge of its dynamics contributes to the understanding of complex processes such as the spectral behavior of water. Among the main properties that interact with electromagnetic radiation are chlorophyll-a suspended solids. From this perspective, the present study aims to analyze in 40 data collection points, the influence of Optically Active Components on the spectral behavior of the waters of the Barra dos Coqueiros Hydroelectric Power Plant (GO) reservoir. To obtain the data, four field campaigns were carried out, which occurred on February 10, 2016 and January 28, 2017 (highest rainfall) and August 04, 2016 and July 07, 2017 (lowest rainfall). The spectral data were obtained by fieldSpec® Hand Held portable spectroradiometer. Chlorophyll-a analysis followed Mackinney's (1941) proposal, suspended solids data, Wetzel and Likens (1991; 2000) and APHA (1998; 2005) methodology and water transparency according to Esteves (1998) and Peixoto et al. (2015). The diagnosis of main information of the water reflectance spectra occurred using techniques: continuum removal, derivative, cluster analysis, surface reflectance extraction from the Landsat 8-OLI satellite image. Based on the results, it was verified several factors of action in the spectral behavior of the reservoir waters of Barra dos Coqueiros UHE (GO), as the climatic seasonality (rainy and dry period) and the forms of land use and occupation, distinguished by agricultural yields, which favor in the fields of February 2016 and January 2017, higher values of suspended solids and chlorophyll-a lower water transparency, resulting in greater reflectance in the spectral bands of green (500 nm to 600 nm) and red (600 nm to 700 nm). In the fields performed in August/2016 and July/2017, reflectance levels influenced by suspended solids and chlorophyll-a are low and the water transparencies showed greater depth, due to the higher absorption of electromagnetic radiation in water in the blue spectral bands (400 nm to 500 nm) and infrared (700 nm to 900 nm). Thus, the geotechnologies applied in this study presented several possibilities for the interpretation of the spectral information of water.
