transmissivity is computed using NDWI from Landsat TM,
then, volume and interaction scatter are removed from
observations based on some assumptions, finally, soil moisture
4
change estimation algorithm is developed using surface scatter
at two acquisitions. The results are validated using in-situ
samples of 0-1 cm. The results showed than the algorithm can
1 Measured
4
R=0.85
•
•
•
•• .!/
Com
L-W
easurecl
Fig.2 The Validation of results for both soybean and com field at four polarizations
be used at L-band, but not at S-band. It is the key in future
work that the algorithm will be advanced to be used at higher
frequency.
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ACKNOWLEDGEMENTS:
This work was supported by funds from NSFC and CAS under
grants 40671140 and kzcx2-yw-301. The EnviSat ASAR data
were provided by ESA through the Category-1 ID: 1406.
