Passive microwave remote sensing for estimation of rice water content in Vietnam

Rice is one of the world´s major staple foods that accounts for 15% of the world´s total cultivated area. In Asia where 94% of the world´s rice is produced, rice is the main source of food and a significant source of income. In Vietnam, rice cultivated area occupies 47% of agricultural land of the country. Rice growing conditions are essential for crop monitoring and yield prediction while rice water content decides the evolutional process and yield per year of the crop. A model for passive microwave emission from water-rice fields, i.e. rice planted on a water layer, is presented in the paper. Field experiments carried out by scientists of Space Technology Application Centre (STAC), Institute of Physics, National Centre for Natural Science and Technology of Vietnam (NCST) using L- and C-band radiometers on water-rice fields are described. An estimation of the rice water content was made that well agreed to ones received by direct measurements. The results are interesting and useful for crop monitoring of agricultural services.