Resource information
In this study, I tried the understanding of the environment state of the farmland in Fukushima and neighbor prefectures in 2011 to contribute to an evaluation of the radioactive substance pollution of the farmland by the accident of Fukushima daiichi nuclear power plant which occurred with East Japan great earthquake disaster of March 11, 2011 with a satellite remote sensing technology. At first I was done interpretation of the paddy fields approximately one month after the accident by using an optical high resolution satellite image. I could interpret the state of rice straw, tilling and difference of water condition, Using large scale satellite image of 50cm high spatial resolution used. In addition, I estimated timings of the tilling and rice strawusing ALOS images just after the accident and SPOT-5 image in the summer. Next, I carried out GIS analysis using DEM data. Paddy fields where fit condition, for example distance from forest and the slope, were distinguished. On the other hand, I detected the water logging paddy fields from satellite images in 2011 to use the fields for a soil pollution evaluation with the radioactive substances in NIAES. Water logging paddy fields distinguished and mapped approximately 3,200,000 over agricultural parcels at Fukushima, Ibaraki, Tochigi and Gunma prefecture. Overall accuracy of detection is 77.0% (n = 2,597), Producer's accuracy is 89.6%. It is consider that the accuracy reduced by influence of East Japan earthquake disaster, the accident at Fukushima daiichi nuclear power plant. Result and accuracy is good and enough for purpose. This result was used as one of the input data for the making of the radioactive substance pollution density distribution map in the farmland soil.
