Study on Method of Monitoring Rice Planting Area Based on MODIS Data
基于MODIS数据的水稻种植面积监测方法研究

Remote sensing technology which is wide-viewed,speediness,low expenses and accurate compared with traditional investigation way is an ideal method for estimation of rice planting area.This paper,taking Fuzhou region which possesses characteristics of a typical hilly area as a demonstration,obtains the rice potential planting area by using land use map,digital elevation data and altitude data firstly,with the help of GIS,and then estimates the leaf area index(LAI)of rice potential planting area by using MODIS remote sensing data. The results of the analysis of the LAI variational curves of three different ground types,i.e.,town,forest and rice field,in Fuzhou district in 2005 indicated that the LAI variational curve of town is no-peak-value model,the LAI variational curve of forest is single-peak-value model,and the LAI variational curve of rice field is double-peak-value model.The characteristics of LAI sequence of the three different ground types are different apparently.This paper analyses the interannual characteristic change of LAI of rice potential planting area in Fuzhou region by using MODIS data during 2001-2005,and the result shows that the LAI based on MODIS data can reflect sensitively the information of rice growth,at the same time,can reflect the pattern that the early and late rice have been planted in Fuzhou region.The course of rice can be judged by using the whole LAI variational curve of rice,and the course of rice that is judged by LAI variational curve in Fuzhou region during 2001-2005 is very close to the data of observation. The estimation model of rice planting area has been established after the best MODIS images have been pciked in the rice growth season,and the subtract images that can reflect the most relative change of LAI in rice potential planting area have been counted.Research result shows that:the relative estimate error of the early and late rice planting area in hilly area using MODIS data is less than 13%,the average value of relative estimate error of the early rice planting area is 9.5%,the average value of relative estimate error of the late rice planting area is 4.1%,and the estimate precision of late rice is better than the early rice.