International Journal of
Water Resources and Environmental Engineering

  • Abbreviation: Int. J. Water Res. Environ. Eng.
  • Language: English
  • ISSN: 2141-6613
  • DOI: 10.5897/IJWREE
  • Start Year: 2009
  • Published Articles: 347

Full Length Research Paper

Characterization of the top sediment layer in coastal intertidal mudflats from medium-to-coarse resolution satellite imagery and field measurements

Timothy Dube
  • Timothy Dube
  • Department of Geography and Environmental Science, University of Zimbabwe, P.O Box MP 167, Mt Pleasant, Harare
  • Google Scholar
Tawanda W. Gara
  • Tawanda W. Gara
  • Department of Geography and Environmental Science, University of Zimbabwe, P.O Box MP 167, Mt Pleasant, Harare
  • Google Scholar
Webster Gumindoga
  • Webster Gumindoga
  • University of KwaZulu-Natal, School of Agriculture, Engineering and Science, Private Bag X01, Scottsville, 3209 South Africa
  • Google Scholar
Emmerson Chivhenge
  • Emmerson Chivhenge
  • Department of Geography and Environmental Science, University of Zimbabwe, P.O Box MP 167, Mt Pleasant, Harare
  • Google Scholar
Tsikai S. Chinembiri
  • Tsikai S. Chinembiri
  • Department of Civil Engineering, University of Zimbabwe, P.O. Box MP 167, Mt Pleasant, Harare, Zimbabwe
  • Google Scholar


  •  Accepted: 21 November 2013
  •  Published: 31 December 2013

Abstract

Intertidal sediments are critically important in controlling intertidal mudflat microphytobenthic primary productivity and the functioning of intertidal ecosystems. This paper demonstrates the possibility of deriving different intertidal sediment properties from coarse-to-medium resolution remote sensing imagery. Supervised and image based classification methods were used to map different substrate types based on the Spectral Angle Mapper (SAM) algorithm. The algorithm characterized different sediment properties from remote sensing data based on field collected and image-extracted endmembers. The results demonstrate that, different substrate types can be derived from coarse-to-medium resolution images using SAM algorithm. Supervised and image-based classification methods performed well in deriving intertidal sediment properties. From the results, sand sediments cover a wide area in extent than clay whereas Normalized Difference Vegetation Index (NDVI) validation results indicate that, clay sediments have higher NDVI values as compared to sand sediments. We conclude that, intertidal sediment properties can be successfully derived from coarse-to-medium resolution satellite imagery.

Key words: Endmember, microphytobenthos, spectral signature, substrates, trios ramses, wadden sea.