کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4459403 1621296 2011 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Soil moisture retrieval over agricultural fields from multi-polarized and multi-angular RADARSAT-2 SAR data
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات کامپیوتر در علوم زمین
پیش نمایش صفحه اول مقاله
Soil moisture retrieval over agricultural fields from multi-polarized and multi-angular RADARSAT-2 SAR data
چکیده انگلیسی

The aim of this study was to estimate soil moisture from RADARSAT-2 Synthetic Aperture Radar (SAR) images acquired over agricultural fields. The adopted approach is based on the combination of semi-empirical backscattering models, four RADARSAT-2 images and coincident ground measurements (soil moisture, soil surface roughness and vegetation characteristics) obtained near Saskatoon, Saskatchewan, Canada during the summer of 2008. The depolarization ratio (χv), the co-polarized correlation coefficient (ρvvhh) and the ratio of the absolute value of cross polarization to crop height (Λvh) derived from RADARSAT-2 data were analyzed with respect to changes in soil surface roughness, crop height, soil moisture and vegetation water content. This sensitivity analysis allowed us to develop empirical relationships for soil surface roughness, crop height and crop water content estimation regardless of crop type. The latter were then used to correct the semi-empirical Water–Cloud model for soil surface roughness and vegetation effects in order to retrieve soil moisture data. The soil moisture retrieved algorithm is evaluated over mature crop fields (wheat, pea, lentil, and canola) using ground measurements. Results show average relative errors of 19%, 10%, 25.5% and 32% respectively for the retrieval of crop height, soil surface roughness, crop water content and soil moisture.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Remote Sensing of Environment - Volume 115, Issue 1, 17 January 2011, Pages 33–43
نویسندگان
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