Abstract
A study was conducted to explore the use of ERS-2 synthetic aperture radar (SAR) data to assess the soil water-content of agricultural farmlands in the Negev Desert, Israel. The ERS-2 data were acquired using the Israel Space Agency (ISA) receiving station operated by Israel Aircraft Industries. Field measurements of volumetric and gravimetric soil water-content and surface roughness were conducted, concurrent with the deployment of well-measured corner reflectors in the field for calibration and geo-rectification of the radar data. Results show that for individual fields, where surface roughness is homogeneous, the radar backscatter cross-section correlates well with the soil water-content component. For mapping water-content over several fields, the surface roughness must be incorporated into any model that correlates radar backscatter with soil water-content. To solve for roughness and soil water-content, two ERS images with different look directions were acquired, providing two different radar signatures. An empirical model was derived to assess water-content conditions, explaining ca. 90% of the backscatter variation using water-content, roughness, and incidence angle. Because it is empirical, the model holds locally and would not be universally true. Therefore, the approach should be tested elsewhere.
Original language | English |
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Pages (from-to) | 449-464 |
Number of pages | 16 |
Journal | Journal of Arid Environments |
Volume | 49 |
Issue number | 3 |
DOIs | |
State | Published - 2001 |
Bibliographical note
Funding Information:The authors wish to acknowledge support from of the Israel Space Agency granted through a strategic infrastructure grant and U.S.A. Office of Naval Research (ONR) grant. We also acknowledge the devoted help of graduate students who spent many hours in the field to collect ground truth data. These include Guy Serbin, Gil Revivo, Michael Ginosov, Ofer Shaulker, Tali Neta, and Eran Barzelei. Alon Tayari provided programming support for this project. The authors also wish to remember Dr M. Fix who was part of the project when it started but passed away unexpectedly.
Funding
The authors wish to acknowledge support from of the Israel Space Agency granted through a strategic infrastructure grant and U.S.A. Office of Naval Research (ONR) grant. We also acknowledge the devoted help of graduate students who spent many hours in the field to collect ground truth data. These include Guy Serbin, Gil Revivo, Michael Ginosov, Ofer Shaulker, Tali Neta, and Eran Barzelei. Alon Tayari provided programming support for this project. The authors also wish to remember Dr M. Fix who was part of the project when it started but passed away unexpectedly.
Funders | Funder number |
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Israel Space Agency | |
Office of Naval Research |