Using Hyperspectral Imaging for the Assessment of Mudflat Surface Stability

Abstract

SMITH, G.M.; THOMSON, A.G.; MÖ LLER, I., and KROMKAMP, J.C., 2004. Using hyperspectral imaging for the assessment of mudflat surface stability.The successful management of fine-grained coastal environments relies on an understanding of, and an ability to predict, their likely future behavior. The latter depends not only on the hydrodynamic conditions to which these coastal systems are exposed, but also on characteristic surface properties that determine erosion shear strength and thus surface stability. Due to the inaccessibility of intertidal areas, precise ground-based measurements of mudflat stability are difficult to conduct. Remote sensing can provide full spatial coverage and non-intrusive measurement. As stability changes on mudflats are linked to subtle differences in mudflat surface characteristics, they can potentially be mapped by hyperspectral data. This paper reports on a study aimed at assessing the suitability of hyperspectral data for estimating mudflat characteristics related to stability. Hyperspectral images were collected along with near contemporary ground measurements. An unsupervised classification resulted in a map that reproduced observed thematic and topographic features, thus highlighting the close link between topography and surface sedimentary characteristics resulting in distinct spectral signatures. Multiple regression analysis was used to relate surface characteristics to hyperspectral data to construct regression equations. Erosion shear stress was estimated directly from the hyperspectral data and also by a relationship with surface characteristics. The results of the thematic class map matched well with the known situation at the site during image acquisition. The quantitative information on surface characteristics suggest that the use of hyperspectral data for the assessment of erosion shear stress, surface stability, and thus the likely future behaviour in this dynamic environment can contribute to a significant improvement in the information needed for the successful management of shallow coastal systems.

Visible, near‐infrared spectrometry for simultaneous assessment of geophysical sediment properties (water and grain size) using the Spectral Derivative–Modified Gaussian Model

“…In nature, sediment parameters are from an environmental point of view closely interrelated [ Deronde et al ., ; Choi et al ., ]. Therefore, hyperspectral remote sensing data can be a useful tool to retrieve biogeophysical properties of sediments such as grain size and water content [ Bryant et al ., ; Carrère et al ., ; Smith et al ., ; Deronde et al ., ; Combe et al ., ; van der Wal and Herman , ; Verpoorter et al ., ]. Small et al .…”

Functional and structural imaging of phototrophic microbial communities and symbioses

“…However, besides investigations of microphytobenthos distributions at a scale of millimetres to metres on sediments and rock platforms (e.g. Murphy et al 2004, 2006, Smith et al 2004, Combe et al 2005) and some HS fluorescence microscopy studies of corals (e.g. Simon-Blecher et al 1996, Ainsworth et .…”

Estuaries

“…Smith et al, 2004;Murphy et al, 2008) and estuarine suspended sediment concentrations. In saltmarsh environments, for example, there is a need for innovative scientific approaches to characterize the hydrodynamic 'roughness' of medium-scale areas (10s to 100s of metres) that consist of both the complex small-scale roughness elements that arise from the presence of a vegetation canopy of a saltmarsh and the topographic roughness elements which comprise tidal creeks, saltpans and marsh cliffs.…”