Abstract
Optical remote sensing was used to provide scientific information to support environmental management in the Gulf of Gabes that is located in the southeastern coast of Tunisia. This region is characterized by shallow continental shelf subjected to semi-diurnal tides. Industrial activities in this area since the early 1970s may have contributed to the degradation of the biodiversity of the ecosystem with eutrophication problems and disappearance of benthic and planktonic species. To assess the long-term effect of anthropogenic and natural discharges on the Gulf of Gabes, the optical environment of the coastal waters is assessed from in situ measurements of total suspended matter concentration (TSM), Secchi depth and turbidity (TU). This monitoring requires regular seaborne measurements (monthly), which is very expensive and difficult to obtain. The objective of the present study is the evaluation of the Moderate Resolution Imaging Spectrometer (MODIS) AQUA data compared with two sampling campaigns realized at the study area. To map turbidity data from MODIS images, a semi-empirical algorithm was applied at band 667 nm. This bio-optical algorithm has already been calibrated and validated on the Belgian coast. The validation of this algorithm on the Gulf of Gabes using in situ measurements of turbidity and remotely sensed turbidity obtained from MODIS imagery shows a correlation coefficient of 68.9%. Seasonal and annual average maps for TSM and TU were then computed over the Gulf of Gabes using MODIS imagery. The obtained results of TSM and TU from remotely sensed data are conformable with those obtained through the analysis of in situ measurements. Therefore, remote sensing techniques offer a better and efficient tool for mapping and monitoring turbidity over the whole region.
Similar content being viewed by others
References
Althuis IJA (1998) Suspended particulate matter detection in the North Sea by hyper spectral airborne remote sensing. Aquat Ecol 32:93–98
Babin M, Stramski D, Ferrari GM, Claustre H, Bricaud A, Obolenski G (2003) Variations in the light absorption coefficients of phytoplankton, non-algal particles, and dissolved organic matter in coastal waters around Europe. J Geophys Res 108. doi:10.1029/2001JC000882
Ben Mustapha K, Hattour A, Mhetli M, El Abed A, Tritar B (1999) Bionomie des étages Infra et Circalittoral du golfe de Gabes. Bull Inst Natn Sci Tech Mer (Tunisie) 26(2):5–48 (French bibliographie)
Bjaoui B, Rais S, Koutitonsky V (2004) Modélisation de la dispersion du phosphogypse dans le golfe de Gabes. Bull Inst Natn Scienc Tech Mer (Tunisie) 31:103–109, French bibliographie
Burollet PF, Clairefond P, Winnock E (1979) La mer Pélagienne (étude sédimentologique et écologique du plateau tunisien et du golfe de Gabes). Géol Méditerranéenne Ann Univ Provence 6(1):1–345, + cartes, (French bibliographie)
Curran PJ, Hansom JD, Plummer SE, Pedley I (1987) Multispectral remote sensing of near shore suspended sediments: a pilot study. Int J Remote Sens 8(1):103–112
Doxaran D, Froidefond J-M, Lavender SJ, Castaing P (2002) Spectral signature of highly turbid waters. Application with SPOT data to quantify suspended particulate matter. Remote Sens Environ 81:149–161
Miller LR, McKee AB (1977) Using MODIS terra 250 m imagery to map concentrations of total suspended matter in coastal xaters. Remote Sens Environ 93:259–266
Morel A, Prieur L (1977) Analysis of variations in ocean color. Limnol Oceanogr 22(4):709–722
Nechad B, Ruddick KG, Neukermans G (2009) Calibration and validation of a generic multisensor algorithm for mapping of turbidity in coastal waters. Proceedings of SPIE “Remote Sensing of the Ocean, Sea Ice, and Large Water Regions” Conference held in Berlin (Germany), 31 August 2009. Proc. of SPIE 7473: 74730H. doi:10.1117/12.830700.
Nechad B, Ruddick KG, Park Y (2010) Calibration and validation of a generic multisensor algorithm for mapping of total suspended matter in turbid waters. Remote Sens Environ 114:854–866
Novo EMM, Hansom JD, Curran PJ (1989) The effect of viewing geometry and wavelength on the relationship between reflectance and suspended sediment concentration. Int J Remote Sens 10(8):1357–1372
Ouillon S, Douillet P, Petrenko A, Neveux J, Dupouy C, Froidefond JM, Andréfouët S, Muñoz-Caravaca A (2008) Optical algorithms at satellite wavelengths for total suspended matter in tropical coastal waters. Sensors 8:4165–4185. doi:10.3390/s8074165
Ritchie JC, Cooper CM, Shiebe FR (1990) The relationship of MSS and TM digital data with suspended sediments, chlorophyll and temperature in Moon Lake, Mississipi. Remote Sens Environ 33:137–148
Sammari C, Koutitonsky VG, Moussa M (2006) Sea level variability and tidal resonance in the Gulf of Gabes, Tunisia. Cont Shelf Res 26:338–350
Sogreah (2002) Protection des ressources marines et côtières du Golfe de Gabes, Sogreah, Tunisie phase préparatoire du projet GEF/WB TF 022968. Rapport de phase 1: Diagnostic, 229 pp (French bibliographie)
Sterckx S, Knaeps E, Bollen M, Trouw K, Houthuys R (2007) Retrieval of suspended sediment from advanced hyperspectral sensor data in the Scheldt Estuary at different stages in the tidal cycle. Mar Geod 30(1):97–108. doi:10.1080/01490410701296341
Tassan S (1994) Local algorithms using SeaWiFS data for the retrieval of phytoplankton, pigments, suspended sediment, and yellow substance in coastal waters. Appl Opt 33(12):2369–2378. doi:10.1364/AO.33.002369
Tilstone G, Moore G (eds) (2002) REVAMP Regional Validation of MERIS Chlorophyll products in North Sea coastal waters: protocols document
Wass PD, Marks SD, Finch JW, Leeks GJ, Ingram JK (1997) Monitoring and preliminary interpretation of in-river turbidity and remote sensed imagery for suspended sediment transport studies in the Humber catchment. Sci Total Environ 194–195:263–283. doi:10.1016/S0048-9697(96)05370-3
Acknowledgments
This study was funded by the Unit of Structure and Geologic Model of University of Sciences of Tunisia. Thanks are extended to the Tunisian Chemical Group GCT for their assistance in collecting the in situ measurement in the Gulf of Gabes. The NASA ocean colors product distribution teams at The Goddard Space Flight Center GSFC are acknowledged for the distribution of MODIS products. This study was carried out in collaboration with the BELCOLOUR-2 project funded by the Belgian Science Policy Office STERO program.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Katlane, R., Nechad, B., Ruddick, K. et al. Optical remote sensing of turbidity and total suspended matter in the Gulf of Gabes. Arab J Geosci 6, 1527–1535 (2013). https://doi.org/10.1007/s12517-011-0438-9
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12517-011-0438-9