Continental Scale Mapping of Tidal Flats across East Asia Using the Landsat Archive
Open Access
- 8 November 2012
- journal article
- research article
- Published by MDPI AG in Remote Sensing
- Vol. 4 (11), 3417-3426
- https://doi.org/10.3390/rs4113417
Abstract
Tidal flats provide habitat for biodiversity, protection from storm surges and sea level rise, and a range of other ecosystem services. However, no simple method exists for mapping tidal flats over large (>1,000 km) extents, and consequently their global status and distribution remain poorly understood. Existing mapping methods are restricted to small areas with known tidal regimes because tidal flats are only fully exposed for a brief period around low tide. Here we present a method for mapping tidal flats over very large areas and demonstrate its utility by mapping the tidal flats of China, the Democratic People’s Republic of Korea and the Republic of Korea. We (i) generated tide height predictions at the acquisition time of all Landsat Archive images of our study area using a validated regional tide model, (ii) selected suitable images acquired in the upper and lower 10% of the tidal range, (iii) converted high and low tide images to a land and water class image derived from the Normalized Differenced Water Index (NDWI) and, (iv) subtracted the high tide classified image from the low tide classified image, resulting in delineation of the tidal flat. Using this method, we mapped the tidal flats for 86.8% of the study area coastline (13,800 km). A confusion matrix for error assessment indicated an accuracy of >85% for the resulting tidal flat map. Our method enables coastal morphology to be mapped and monitored at continental scales, providing critical data to inform coastal adaptation measures for sea level rise, for monitoring coastal habitat loss and for developing ecosystem-based coastal conservation measures.This publication has 24 references indexed in Scilit:
- Sinking deltas due to human activitiesNature Geoscience, 2009
- Detecting the intertidal morphologic change using satellite dataEstuarine, Coastal and Shelf Science, 2008
- Classification of sediments on exposed tidal flats in the German Bight using multi-frequency radar dataRemote Sensing of Environment, 2008
- A simple waterline approach for tidelands using multi-temporal satellite images: A case study in the Yangtze DeltaEstuarine, Coastal and Shelf Science, 2008
- Waterline extraction from Landsat TM data in a tidal flat: A case study in Gomso Bay, KoreaRemote Sensing of Environment, 2002
- Optimizing Remotely Sensed Solutions for Monitoring, Modeling, and Managing Coastal EnvironmentsRemote Sensing of Environment, 2000
- Monitoring changing position of coastlines using Thematic Mapper imagery, an example from the Nile DeltaGeomorphology, 1999
- Remote sensing techniques in estuaries and coastal zones an updateInternational Journal of Remote Sensing, 1999
- Detection of shoreline changes for tideland areas using multi-temporal satellite imagesInternational Journal of Remote Sensing, 1998
- A review of remote sensing for the assessment and management of tropical coastal resourcesCoastal Management, 1996