Abstract: In order to improve the accuracy and efficiency of remote sensing monitoring of crop planting information in plain irrigation area in Inner Mongolia,China,this paper proposes a method of crop planting information extraction based on timeseries NDVI profile.Selecting Tumoteyou County of Inner Mongolia as the study area,using the multitemporal Landsat images covering crop growing season in 2015 as data sources,the study area was divided into vegetation covering area,nonvegetation covering area and water covering area according to the NDVI value range of ground objects.In the area of vegetation covering,the forest area and grass area were extracted successively according to the NDVI curve differences of forest and grass.The rest areas were farmland in vegetation covering area.According to the NDVI profile of wheat,corn,sunflower and zucchini,the decisiontree was built,and the spatial planting information of the crops was extracted successively according to the decisiontree.Building the decisiontree is mainly based on the difference of NDVI average curve characteristics between crops,forest and grass.However,the change range of each crop NDVI due to their own different growth at the same time should also be fully considered.Appling the decisiontree,the extraction area of land use and crop is close to the actual statistical area.The overall accuracy of land use classification was 85.71% and the Kappa coefficient is 0.75.The overall accuracy of crop classification was 82.69% and the Kappa coefficient was 0.77.The results show that the research method can monitor crop spatial planting information in the region accurately and effectively.

Key words: Landsat, timeseries, NDVI, crop planting structure, decisiontree