Seagrass habitat mapping: how do Landsat 8 OLI, Sentinel-2, ZY-3A, and Worldview-3 perform?

This study assessed recently launched multispectral sensors to map seagrass properties for a similar to 150km(2) shallow bank in Moreton Bay, Australia. We utilised a previously developed semi-automated, object-based image analysis classification routine for our comparison, utilising field and image data as input. Field data were collected through georeferenced photograph transects which were analysed for species composition and percentage cover. Field data collection occurred close to image capture from Landsat 8 Operational Land Imager (30m pixel), Sentinel-2 (10m pixel), Ziyuan-3A (5m pixel), and WorldView-3 (2m pixel) sensors. The output maps had average overall accuracies of 66% for species and 57% for percentage cover maps. The study concluded that all sensors tested were suitable for mapping seagrass meadows in clear shallow waters, but the higher resolution sensors provided more detail and were considered more representative. The choice of sensor would depend upon the extent of the seagrass meadow, available funds and frequency of observation.