Fig 1.
Map of the Bosten Lake watershed.
Table 1.
Remote sensing image data.
Table 2.
The relationship between Landsat image data OLI, Sentinel-2data and soil salt.
Table 3.
Relationship between soil salt content and spectral index.
Table 4.
The soil salinity data statistics in Bosten Lake watershed.
Fig 2.
OLI data of the raw image (R), first derivative (FD), second derivative (SD), and third derivative (TD).
Fig 3.
MSI data of the raw image (R), first derivative (FD), second derivative (SD), and third derivative (TD).
Table 5.
Relationship between soil salt content and spectral characteristics of MSI and OLI data.
Table 6.
Relationship between soil salt content and measured spectral index in Bosten Lake Watershed.
Fig 4.
Spectral DI, NDI, and RI indices of soil salinization based on OLI data.
Fig 5.
Spectral DI, NDI and RI indices of soil salinization based on MSI data.
Table 7.
Optimal parameter selection of SVM based on GS method.
Fig 6.
Scatter plot of measured and predicted soil salinity in GS-SVM models.
Table 8.
Validation of SVM model for estimating soil salinity in Bosten Lake Watershed.
Fig 7.
Map of soil salt content based on the SVM model.
Table 9.
Comparison of the accuracy of estimating soil salt content by different models.