|De La Cruz, F.|
Submitted to: International Symposium on Recent Advances in Quantitative Remote Sensing
Publication Type: Abstract Only
Publication Acceptance Date: 6/23/2010
Publication Date: 9/27/2010
Citation: Alonso, L., Moreno, J., Moran, M.S., De La Cruz, F. 2010. PRELIMINARY RESULTS FROM THE AgriSAR2009 CAMPAIGN FOR IRRIGATED AND NON-IRRIGATED CROPS IN BARRAX SPAIN. [abstract].Third International Symposium Recent Advances in Quantitative Remote Sensing (RAQRS). September 27 - October 1, 2010. Valencia, Spain. Interpretive Summary:
Technical Abstract: The European Space Agency (ESA) along with multiple university and agency investigators joined to conduct the AgriSAR Campaign in 2009. The main objective was to analyse a dense time series of RADARSAT-2 quad-pol data to define and quantify the performance of Sentinel-1 and other future ESA C-Band SAR missions for classifying and monitoring agricultural crops within Global Monitoring for Environment and Security (GMES) land monitoring services. In the Barrax region in La Mancha, Spain, 57 RadarSat-2 C-band quad-pol SAR images and 6 RapidEye 4-band optical images were acquired from April to September 2009, covering multiple large fields of irrigated and non-irrigated crops. Using ascending and descending RadarSat orbits and incidence angles ranging from 23° to 41°, SAR images were acquired on average every 3 days. On the ground, records were kept of meteorological conditions, precipitation, and for select fields, crop type, phenology, irrigation and yield. An analysis of the sensitivity of SAR backscatter (so) to crop and soil conditions was conducted using the entire multi-view, quad-pol image time-series for large fields of corn, barley, wheat, onion, alfalfa and oats in Barrax. Preliminary results showed that 1) the cross-polarized so (HV) was sensitive to the changes in vegetation structure associated with crop seasonal growth and harvest, 2) the co-polarized so (HH or VV) was sensitive to precipitation and irrigation events when the crop leaf density was low, 3) large day-to-day variations in SAR so unrelated to crop and soil conditions were explained by the variations in the RadarSat satellite/sensor orientation, with the largest variations explained by crop furrow size and orientation, and 4) the temporal trend and overall amplitude of SAR so could be related to crop type and irrigation. Related to the AgriSAR objective of deriving agricultural information from time-series SAR products, it appeared that multi-polarization provided relatively independent information about crop phenology and soil moisture; the 3-day repeat was important for discriminating surface signal from differences in acquisition configuration; and the dense time-series was particularly suited for discriminating crop type, crop phenology and soil moisture conditions. The next step in this analysis is to interpret the RadarSat/RapidEye time-series using a combined crop growth/radar backscatter modeling system to best utilize the time-series information for land monitoring.