Coastal area shoreline shifting detection and water salinity assessment based on remote sensing and google earth engine platform: Active aquacultural case study area in Saudi Arabia

Coastal areas are more vulnerable due to the high extreme natural events and anthropogenic activates are destroying the environment. Food demand is gradually increasing because of the population pressure, while alternative planning like aquaculture land is increasing in some parts of the Saudi Arabia. Global sea level rise is also a triggering factor for shoreline change in the coastal environment with high soil salinity increase. Without any sustainable planning and management, those areas are gradually affected through shoreline shifting and soil salinity-related problems. Remote sensing is the most powerful tool to detect those earth’s surface changes through earth observational datasets. Landsat series datasets were applied for detecting shoreline shifting, aquaculture land identification, and soil salinity along with automatic water area detection using Google Earth Engine cloud computing platform from 1994 to 2023 near Alqalh area, Saudi Arabia. Decadal shoreline shifting observed like 4.48 km2 (1994-2002), 8.82 km2 (2002-2014), 6.61 km2 (2014-2023) and 9.24 km2 (1994-2023), while overall 43.47 km2 (1994-2023) of the area is accretion measured. In the initial periods (1994) aquaculture land did not exit in this area but in the recent time (2023) this area have 71.16 km2 (13.38%) of aquaculture land. Some geo-spatial indices also applied for soil salinity, vegetation and water body area where Vegetation Soil Salinity Index (VSSI) observed high salinity in the year of 2024 due to huge aquaculture land and shoreline shifting towards north-west, south and south-east position of the study area. This investigation outcomes may help local planners in developing novel adaptation strategies in order to protect the environmental degradation.  Keywords: Coastal area water assessment; Shoreline shifting; Soil salinity; Aquaculture; Remote sensing.