Applications of remote sensing in the monitoring of rice crops

Abstract

Remote sensing, which is the science of acquiring information re g a rding the earth's surface without physical contact, is becoming i n c reasingly important in many fields today. Recently, remote sensing is finding its way into rice monitoring applications. Studies on satellite images have shown that rice fields produce different brightness patterns at different plant growth stages, allowing the fields to be classified. However, there is a need for further re s e a rch into understanding the interactions between electro m a g n e t i c waves and rice fields through the development of a theoretical model. This paper describes the development of a theoretical model that can be verified by field measurements to enable correct interpretation of remote sensing data and rice growth monitoring by using the change detection method. Not much is known about how electromagnetic waves interact with rice fields and how rice c rops scatter these waves back to the satellite. Even though rice fields can be classified using the backscattering values and the rice growth can be monitored, a comprehensive study of the theoretical scattering model is crucial to ensure correct application of remote sensing data. The objectives of this study are to investigate the relationship between microwave backscatter signature s and rice growth and to monitor rice growth using satellite images. Results using multi-temporal RADARSAT i m a g e ry have confirmed that the backscatter can create a good separation for rice planting stages.