Monitoring of rice in small paddy fields using multi-temporal Sentinel-1 data
Issue Date
10-2017
Abstract
Rice is the staple food for more than half of the world's population. The prompt assessment of its conditions is critical for diagnosis and decision making especially under threats of climate change. With the recent availability of C-band synthetic aperture radar (SAR) data from Sentinel-1, a 6320-m2 rice paddy field employing farmer's practice in Argao, Cebu, Philippines was monitored, such that its growth can be modeled from the satellite's backscatter readings. The multi-temporal backscatter of rice and its polarimetric difference were compared with reference surfaces. The results have shown that in terms of vertical-vertical (VV) and vertical-horizontal (VH) polarized backscatter magnitude alone, rice cannot be differentiated from the other reference surfaces. However in terms of its trend over time, rice can be identified using its unique specular signature during land preparation. The polarimetric difference (VV-VH and VH-VV) was also found to be a better metric in identifying rice areas. The results have shown that canopy height and hill diameter are highly correlated with the VH polarized backscatter with R2 values equal to 0.74 and 0.65, respectively. The other biophysical parameters (i.e. number of tillers, crop height, hill diameter) measured in situ did not correlate well with backscatter and its polarimetric difference. Sentinel-1 has the potential to detect small vegetative differences at closely-located ground truth (GT) points. It is recommended that further studies be conducted in this area such that the use of Sentinel-1 as an agricultural monitoring tool be maximized.
Source or Periodical Title
38th Asian Conference on Remote Sensing - Space Applications: Touching Human Lives, ACRS 2017
Document Type
Article
Physical Description
illustrations, tables, graphs
Language
English
Subject
Backscatter, Cebu, Philippines, Polarimetric difference, Synthetic aperture radar
Recommended Citation
Nuevo, R.U., Saludes, R.B., Dorado, M.A., Bantayan, N.C. (2017). Monitoring of Rice in Small Paddy Fields Using Multi-Temporal Sentinel-1 Data. 38th Asian Conference on Remote Sensing - Space Applications: Touching Human Lives, ACRS 2017, 1-10.
Digital Copy
yes