Spatial variability of arsenic speciation in the Gironde Estuary: Emphasis on dynamic (potentially bioavailable) inorganic arsenite and arsenate fractions

This study investigated the use of frequent metre-scale resolution Pléiades satellite imagery to monitor water quality parameters in the highly turbid Gironde Estuary (GE, SW France). Pléiades satellite data were processed and analyzed in two representative test sites of the GE: 1) the maximum turbidity zone and 2) the mouth of the estuary. The main objectives of this study were to: (i) validate the Dark Spectrum Fitting (DSF) atmospheric correction developed by Vanhellemont and Ruddick (2018) applied to Pléiades satellite data recorded over the GE; (ii) highlight the benefits of frequent metre-scale Pléiades observations in highly turbid estuaries by comparing them to previously validated satellite observations made at medium (250/300 m for MODIS, MERIS, OLCI data) and high (20/30 m for SPOT, OLI and MSI data) spatial resolutions. The results show that the DSF allows for an accurate retrieval of water turbidity by inversion of the water reflectance in the near-infrared (NIR) and red wavebands. The difference between Pléiades-derived turbidity and field measurements was proven to be in the order of 10%. To evaluate the spatial variability of water turbidity at metre scale, Pléiades data at 2 m resolution were resampled to 20 m and 250 m to simulate typical coarser resolution sensors. On average, the derived spatial variability in the GE is lower than or equal to 10% and 26%, respectively, in 20-m and 250-m aggregated pixels. Pléiades products not only show, in great detail, the turbidity features in the estuary and river plume, they also allow to map the turbidity inside ports and capture the complex spatial variations of turbidity along the shores of the estuary. Furthermore, the daily acquisition capabilities may provide additional advantages over other satellite constellations when monitoring highly dynamic estuarine systems.

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Sampling and mapping of heterogeneous surfaces: multi-resolution tiling adjusted to spatial variability

International Journal of Geographical Information Systems ◽

10.1080/026937996137756 ◽

1996 ◽

Vol 10 (7) ◽

pp. 851-876

Author(s):

Ferenc Csillag ◽

Miklos Kertesz ◽

Agnes Kummert

Keyword(s):

Spatial Variability ◽

Heterogeneous Surfaces

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Spatial variability induces generalization in contextual cueing.

Journal of Experimental Psychology Learning Memory and Cognition ◽

10.1037/xlm0000796 ◽

2020 ◽

Vol 46 (12) ◽

pp. 2295-2313

Author(s):

Yoko Higuchi ◽

Yoshiyuki Ueda ◽

Kazuhisa Shibata ◽

Jun Saiki

Keyword(s):

Spatial Variability ◽

Contextual Cueing

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Spatial variability in responses to environmental conditions in Southern Hemisphere long-finned pilot whales

Marine Ecology Progress Series ◽

10.3354/meps13109 ◽

2019 ◽

Vol 629 ◽

pp. 207-218 ◽

Cited By ~ 1

Author(s):

V Hamilton ◽

K Evans ◽

B Raymond ◽

E Betty ◽

MA Hindell

Keyword(s):

Spatial Variability ◽

Southern Hemisphere ◽

Environmental Conditions ◽

Pilot Whales

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DISTRIBUIÇÃO DA EVAPORAÇÃO EM ESTUFA PLÁSTICA NA PRIMAVERA

Irriga ◽

10.15809/irriga.2001v6n3p120-127 ◽

2001 ◽

Vol 6 (3) ◽

pp. 120-127

Author(s):

Reginaldo Ferreira Santos ◽

Antonio Evaldo Klar

Keyword(s):

Spatial Variability ◽

Pan Evaporation ◽

Spring Season ◽

Class A ◽

Agricultural Sciences ◽

E Mail ◽

Center Area ◽

Class A Pan

DISTRIBUIÇÃO DA EVAPORAÇÃO EM ESTUFA PLÁSTICA NA PRIMAVERA Reginaldo Ferreira SantosCentro de Ciências Exatas e Tecnológica da UNIOESTE- CP 711CEP 858114-110, Cascavel, PR - Fone: 0XX45 2203155. E-mail: [email protected] Evaldo KlarDepartamento de Engenharia Rural - Faculdade de Ciências Agronômica- UNESP - CEP 18603-970 - Botucatu, SP. CP: 237. E-mail: [email protected] 1 RESUMO O presente trabalho teve como objetivo avaliar a distribuição da evaporação no interior de uma estufa plástica, com uma cultura de pimentão, através da variabilidade espacial e comparar a evaporação dos microevaporímetros com os valores do Tanque classe "A". O experimento foi conduzido no Campus da Universidade Estadual Paulista - FCA/UNESP, no período de primavera, em estufa plástica de polietileno de baixa densidade (PEBD). Na distribuição da evaporação em estufa com orientação norte/sul, verificou-se que as maiores evaporações ocorreram nas extremidades sul e norte tendente ao lado oeste. Já as menores evaporações localizaram-se no centro. No período de primavera, a evaporação média nos microevaporímetros superestimou em 55% a evaporação determinada no Tanque classe "A". UNITERMOS: evaporação, geoestatística, estufa. SANTOS, R.F, KLAR, A.E. EVAPORATION DISTRIBUTION INSIDE A PLASTIC TUNNEL IN THE SPRING SEASON 2 ABSTRACT The main aim of this study was to verify the evaporation distribution inside a plastic tunnel, with pepper crop, oriented to north/south, through spatial variability and to compare Class A Pan evaporation to punctual evaporations of 40 equidistant microevaporimeters placed from 50cm the soil. The study was carried out at the College of Agricultural Sciences/UNESP, Botucatu – SP in the spring season. The highest evaporation occurred next to north and to south sides of the tunnel, with tendency to west. Consequently, the lowest evaporations occurred at the center area. The microevaporimeter evaporations were 55% higher than those obtained from Class A Pan. KEYWORDS: evaporation distribution, microevaporimeter.

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