Title
Mapping and Characterization of Hydrological Dynamics in a Coastal Marsh Using High Temporal Resolution Sentinel-1A Images.
Abstract
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. This study assesses advantages of using radar data from the recently launched Sentinel-1A satellite to monitor hydrological dynamics of the Poitevin marshland in western France. We analyze a time series of 14 radar images acquired in VV and HV polarizations from December 2014 to May 2015 with a 12-day time step. Both polarizations are used with a hysteresis thresholding algorithm which uses both spatial and temporal information to distinguish open water, flooded vegetation and non-flooded grassland. Classification results are compared to in situ piezometric measurements combined with a Digital Terrain Model derived from LiDAR data. Results reveal that open water is successfully detected, whereas flooded grasslands with emergent vegetation and fine-grained patterns are detected with moderate accuracy. Five hydrological regimes are derived from the flood duration and mapped. Analysis of time steps in the time series shows that decreased temporal repetitivity induces significant differences in estimates of flood duration. These results illustrate the great potential to monitor variations in seasonal floods with the high temporal frequency of Sentinel-1A acquisitions.
Year
DOI
Venue
2016
10.3390/rs8070570
REMOTE SENSING
Keywords
Field
DocType
radar,SAR,Sentinel-1,remote sensing,hysteresis,time series,flood,wetland,marshes,water management
Radar,Radar imaging,Vegetation,Synthetic aperture radar,Remote sensing,Wetland,Digital elevation model,Geology,Temporal resolution,Flood myth
Journal
Volume
Issue
Citations 
8
7
2
PageRank 
References 
Authors
0.48
0
8
Name
Order
Citations
PageRank
Cécile Cazals120.48
Sébastien Rapinel231.59
Pierre-Louis Frison3708.10
Anne Bonis420.48
Grégoire Mercier560552.49
Clément Mallet613415.93
Samuel Corgne7334.74
Jean-Paul Rudant89012.90