Spatial Delineation of Rice Yield and Production by the Combination of Rice Crop Modelling and Remote Sensing: A Case Study in Soc Trang Province, Vietnam

Abstract

Vietnam's economy mainly depends on the growth of agricultural production. The forecasting yields to consolidate information to assure food security, monitoring, and mapping rice accurately are essential. The study is aimed to (i) delineate the rice distribution status; (ii) simulate the rice yield by using the AQUACROP model; (iii) integrate maps and rice yield to delineate the rice production extent in Soc Trang province. The method involves combining MODIS remote sensing data (MOD13Q1, MOD13A1 at 250m resolution, eight-day intervals) with the AQUACROP rice yield prediction results at 9 study sites within the area. The study delineated three primary rice cropping seasons (Winter-Spring, Spring-Autumn, Autumn-Summer), separated into eight specific rice cropping seasons, depending on the date or rice sowing/transplanting and harvesting. Besides, the difference in rice sowing time of the three main rice cropping seasons was identified and delineated. The simulated rice yield always higher observed rice yields at all seasons, from -8.65 to 22.20% in the Winter-Spring season, 5 to 28.6% in Spring-Summer season, and -1 to 49% in Summer-Autumn. The results were validated by comparing with the government statistical results, which was a very close correlation. The results suggested that we can use the MODIS satellite image for delineating rice cropping status. The rice yield and production can be simulated and delineated by the combination with the rice crop model.