Poitevin marsh wetland

Sentinel-1 CSAR IW acquired on 12 March 2015 at 17:55:55 UTC
Sentinel-1 CSAR IW acquired on 30 January 2016 at 17:56:01 UTC
Author(s): Sentinel Vision team, VisioTerra, France - svp@visioterra.fr
Keyword(s): land, coastal, flooding, wetland, marsh, Poitou, France
Fig. 1 - S1 C-SAR (12.03.2015) over the Poitevin marsh, near the Atlantic French coast - VV/VH/NDI(VH,VV) composite.
2D view
Fig. 2 - S1 C-SAR (30.01.2016) - idem over the CCI-LC 2010 produced by ESA.
2D view
Fig. 3 - S1 C-SAR (12.03.2015) - Zoom over the marsh of Lairoux.
2D view
Fig. 4 - S1 C-SAR (12.03.2015) and in-situ photographs.
3D view
Cécile Cazals, researcher for l’Institut national de l’information géographique et forestière (IGN) in France described fig 2: “Three main tones are clearly visible: (a) cyan-dominated areas correspond to non-flooded grassland; (b) orange areas correspond to flooded vegetation; and (c) dark blue areas correspond to open water (see fig. 4).”
Fig. 5 - S1 C-SAR (30.01.2016) - Zoom over the marsh of Lairoux.
2D view
Fig. 6 - Flood duration map computed from multiple acquisitions with its caption – IGN BD Ortho basemap.

Cécile Cazals, commented: “In Europe, water levels in wetlands are widely controlled by environmental managers and farmers. However, the influence of these management practices on hydrodynamics and biodiversity remains poorly understood. Remote sensing appears to be an efficient way to monitor floods dynamics in natural environment.

Due to the specular reflexion of C-band radar wave occuring over water surfaces, all water bodies can be characterized (in dark blue in the images fig. 1 to fig. 5) by Sentinel-1. Its temporal resolution of 6 days allows an accurate flood dynamic monitoring, deriving several indicators like floods duration, drying period or spatial coverage of wetland. Theses indicators are essential to a better water levels management, improve our knowledge of wetland and preserve biodiversity expression.”
The views expressed herein can in no way be taken to reflect the official opinion of the European Space Agency or the European Union.
Contains modified Copernicus Sentinel data 2024, processed by VisioTerra.
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