Screening analysis of river seston downstream of an effluent discharge point using near-infrared reflectance spectrometry and wavelet-based spectral region selection.
A methodology for screening analysis of river seston downstream of an industry effluent by using near-infrared reflectance spectrometry was developed. A wavelet transform (WT)-based strategy is used to select a spectral region in which the effect of the effluent on the optical properties of the seston is more evident. The methodology was applied to samples from the River Mumbaba in northeast Brazil. Four sites were monitored: two upstream (1 and 2), one at the discharge point of the effluent (3), and another downstream (4). Soft Independent Modelling of Class Analogies (SIMCA) models were built for site 1 and were then applied to the classification of samples from sites 2 and 4. The results reveal that the WT-based spectral region selection is essential to ensure good sensitivity and specificity with respect to the detection of events associated to the effluent discharges at site 3. In fact, the changes in site 4 caused by the effluent are masked by other environmental factors when the full spectrum is employed.
Universidade Federal da Paraíba, CCEN, Departamento de Química, Caixa Postal 5093, 58051-970-João Pessoa, PB, Brazil.
Vânia Maria
VM
de Medeiros
Mário César
MC
Ugulino Araújo
Roberto Kawakami
RK
Harrop Galvão
Edvan Cirino
EC
da Silva
Teresa Cristina
TC
Bezerra Saldanha
Ilda Antonieta
IA
Salata Toscano
Maria do Socorro
Mdo S
Ribeiro de Oliveira
Sueny Kêlia
SK
Barbosa Freitas
Manoel Mariano
MM
Neto
D001938:Brazil; D004784:Environmental Monitoring / Q000379:methods*; D007220:Industrial Waste; D008962:Models, Theoretical; D025341:Principal Component Analysis; D045483:Rivers / Q000737:chemistry*; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D013783:Textile Industry; D014865:Waste Disposal, Fluid
D007220:Industrial Waste