Discrimination of rice crop grown under different cultural practices using temporal ERS-1 synthetic aperture radar data

Radar remote sensing has a significant role to play in remote sensing based crop inventory programmes due to its independence from cloud cover. In this study, an attempt has been made to evaluate the utility of temporal ERS-1 SAR data to classify rice crop grown in different growing environments. The sites represent four major types of lowland cultivation practice prevailing in India. Results showed more than 90% classification accuracy for all types of wetland rice using three-date SAR data. Data acquired during the early vegetative stage were found essential for high accuracy. The accuracy was mainly affected by the presence of rivers/streams in the scene. High accuracy was obtained for lowland intermediate and irrigated rice areas. A significant effect of wind was observed on the radar backscatter from stagnant water bodies but not on the rice fields during early growth stages. The study indicates the feasibility of operational use of ERS SAR data for estimation of areas of rice crop grown under lowland cultural practice.