Extraction Of Planting Structure And Irrigation Area Information In Shijin Irrigation District

At present, agricultural water use accounts for about 70% of the total water consumption in China, of which more than 90% are for irrigation. Agriculture is the foundation of our national economy, with the increase of population; agricultural products demand increasing, under the situation of shortage of water resources, making full use of water resources is important. Therefore, extracting the planting structure and irrigation area information has important significance for monitoring water irrigation.In this paper, we take Shijin irrigation area as the research object, MODIS EVI data products, GF-1 16 m multispectral data and phenology data would be used to extract the planting structure with the method of visual interpretation and decision tree of the study area. The visual interpretation accuracy of GF-1 images is more than 90%. Compared the decision tree results with the visual interpretation results shows GF-1 EVI products’ extraction accuracy is more than 90%, and MODIS EVI products’ extraction accuracy is more than 80%. Land surface temperature, vegetation supply water index and temperature vegetation dryness index were retrieved and calculated based on Landsat8 data. By analyzing the changes of the LST and the drought condition in irrigation area, the extraction threshold value of the irrigation area was determined, and then the image was clipped by the wheat vector, the wheat irrigation area was extracted. Comparing and analyzing the difference of extraction irrigation area is less than 5%, the distribution of irrigation area is basically similar. With the three methods of extraction irrigation area, the overlap is above 80%. The results of the three methods have had a good consistency.The results of this study provide the application of remote sensing technology in planting structure and irrigation area extraction with a new idea. This study provides a technical support that the Shijin irrigation area needs to check the statistical data of water consumption. And it also provides our country water resources managements with scientific basis and technical accumulation.