Abstract
Estimation of the total phosphorus concentration distribution using satellite images on the Mekong River flood-plain was carried out. Partial least squares regression analysis was applied to satellite images of rainy season and dry season, and chlorophyll a concentration was obtained. Past studies about for relational expression between chlorophyll a and total phosphorus were examined, and the total phosphorus concentration was also determined from the concentration of chlorophyll a. From the regression equation in the rainy season the concentration distributions in the rainy season and the dry season were estimated. from the regression equation in the dry season, the concentration distributions in the rainy season and dry season were estimated. The correlation coefficient between the estimated value of the rainy season and the observation value by the regression equation of the rainy season was 0.97, and the correlation coefficient in the dry season was 0.070. The correlation coefficient in the dry season by the regression equation of the dry season was 0.66, whereas the correlation coefficient in the rainy season was -0.49. It is understood that the regression equation can not be applied to different seasons and it was found that it is necessary to obtain a regression equation on suitable season for more accurate estimation.
