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DOI	10.1007/s12518-021-00370-7
	Modeling of surface soil moisture using C-band SAR data over bare fields in the tropical semi-arid region of India
	Gururaj, Punithraj; Umesh, Pruthviraj; Shetty, Amba
通讯作者	Gururaj, P (corresponding author), NITK, Dept Water Resources & Ocean Engn, Surathkal, India.
来源期刊	APPLIED GEOMATICS
ISSN	1866-9298
EISSN	1866-928X
出版年	2021
英文摘要	Spatial variability of surface soil moisture is a prime factor in modeling many environmental and meteorological processes. This study aims to model surface soil moisture in bare fields using Sentinel-1A SAR data at a regional scale. The site/plot selected for the study falls in the tropical semi-arid region of Malavalli, Karnataka, India. The study site is divided into 43 grids to collect soil moisture samples from bare field plots synchronized with Sentinel-1A pass. Sentinel-1A, dual-polarized (VV and VH) data with 5.405-GHz frequency and central incidence angle of 33 degrees are used. Six SAR imageries were procured from ESA, out of which five were used to model field soil moisture and one for validation. Processing of the SAR imageries is carried out using SNAP 7.0 software's standard tools, and the backscattered energy of each sample grid is extracted using R software. The relation between SAR backscatter energy with soil parameters like moisture, dielectric constant, and roughness was used to model soil moisture. Results revealed that Sentinel-1A has a high potential to record the soil moisture spatial variation at the plot scale. Volumetric soil moisture and backscattered energy showed a positive correlation with R-2 of 0.59 and 0.51 for VV and VH polarization. Dielectric constant also showed a positive correlation with backscattered energy having R-2 of 0.54 and 0.48 for VV and VH polarization. With this knowledge, surface soil moisture is modeled over bare fields and mapped. Soil moisture modeled is validated using field data, which has R-2 of 0.88 and RMSE of 1.93. The developed model and surface soil moisture map are helpful in regional hydrological studies and crop water requirement assessment.
英文关键词	SAR Sentinel-1A Soil moisture mapping Plot scale Semi-empirical model
类型	Article ; Early Access
语种	英语
收录类别	ESCI
WOS记录号	WOS:000654821900001
WOS关键词	INTEGRAL-EQUATION MODEL ; ROUGHNESS MEASUREMENT ; SPATIAL-RESOLUTION ; RADAR DATA ; SENTINEL-1 ; RETRIEVAL ; IMAGES ; BACKSCATTERING ; ASSIMILATION ; SENSITIVITY
WOS类目	Remote Sensing
WOS研究方向	Remote Sensing
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/353000
作者单位	[Gururaj, Punithraj; Umesh, Pruthviraj; Shetty, Amba] NITK, Dept Water Resources & Ocean Engn, Surathkal, India
推荐引用方式 GB/T 7714	Gururaj, Punithraj,Umesh, Pruthviraj,Shetty, Amba. Modeling of surface soil moisture using C-band SAR data over bare fields in the tropical semi-arid region of India[J],2021.
APA	Gururaj, Punithraj,Umesh, Pruthviraj,&Shetty, Amba.(2021).Modeling of surface soil moisture using C-band SAR data over bare fields in the tropical semi-arid region of India.APPLIED GEOMATICS.
MLA	Gururaj, Punithraj,et al."Modeling of surface soil moisture using C-band SAR data over bare fields in the tropical semi-arid region of India".APPLIED GEOMATICS (2021).