Analysis of L-Band SAR Data for Soil Moisture Estimations over Agricultural Areas in the Tropics
Abstract
:1. Introduction
2. Study Site and Dataset Description
2.1. Description of the Study Site
2.2. Dataset Description
2.2.1. SAR Data
2.2.2. Ground Measurements
Soil Moisture Measurements
Leaf Area Index Measurements
Roughness Measurements
3. Methodology
3.1. Backscattering Model
3.1.1. Water Cloud Model (WCM)
3.1.2. Soil Backscattering Models
3.2. Statistical Parameters
4. Results and Discussions
4.1. Analysis of Radar Signal Sensitivity to Soil Moisture
4.1.1. Bare Soil
4.1.2. Surfaces with Vegetation Cover
4.2. Backscattering Models
4.2.1. Bare Soil Backscattering
4.2.2. Vegetation Covered Soil Backscattering
4.3. Soil Moisture Estimation
5. Conclusions
Author Contributions
Acknowledgments
Conflicts of Interest
References
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Model | RMSE (DB) | |
---|---|---|
HH pol | HV pol | |
AIEM | 2.2 | - |
IEM-Bagh | 2.9 | - |
Oh’92 | 5.4 | 9.4 |
Dubois | 2.1 | - |
Baghdadi | 1.2 | 2.1 |
Crop | Pol | A | B | RMSE (dB) | R2 |
---|---|---|---|---|---|
Turmeric | HH | 0.037 | 0.05 | 1.3 | 0.68 |
HV | 5.12 | 6 × 10−5 | 2.2 | 0.41 | |
Marigold | HH | 0.031 | 0.069 | 1.6 | 0.35 |
HV | 1.06 | 0.00035 | 1.9 | 0.28 | |
Sorghum | HH | 0.038 | 0.11 | 0.9 | 0.77 |
HV | 0.006 | 0.13 | 1.3 | 0.42 |
Crop | Pol | RMSE (vol.%) |
---|---|---|
Turmeric | HH | 6.7 |
HV | 7.9 | |
Marigold | HH | 8.7 |
HV | 11 | |
Sorghum | HH | 15.7 |
HV | 16.1 |
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Zribi, M.; Muddu, S.; Bousbih, S.; Al Bitar, A.; Tomer, S.K.; Baghdadi, N.; Bandyopadhyay, S. Analysis of L-Band SAR Data for Soil Moisture Estimations over Agricultural Areas in the Tropics. Remote Sens. 2019, 11, 1122. https://doi.org/10.3390/rs11091122
Zribi M, Muddu S, Bousbih S, Al Bitar A, Tomer SK, Baghdadi N, Bandyopadhyay S. Analysis of L-Band SAR Data for Soil Moisture Estimations over Agricultural Areas in the Tropics. Remote Sensing. 2019; 11(9):1122. https://doi.org/10.3390/rs11091122
Chicago/Turabian StyleZribi, Mehrez, Sekhar Muddu, Safa Bousbih, Ahmad Al Bitar, Sat Kumar Tomer, Nicolas Baghdadi, and Soumya Bandyopadhyay. 2019. "Analysis of L-Band SAR Data for Soil Moisture Estimations over Agricultural Areas in the Tropics" Remote Sensing 11, no. 9: 1122. https://doi.org/10.3390/rs11091122