ATTEMPT OF AUTOMATIC JUDGEMENT OF THE VISUAL CYANOBACTERIA INDEX (VCI) USING DIGITAL IMAGES

The overgrowth of cyanobacteria, which causes Algal bloom will continue to be a major concern regarding the eutrophication problem in dam reservoirs and lakes. The current main-stream monitoring method of Algal bloom is visual examination, in which administrators of dam reservoir and lake keep records using “Apprearance Algal bloom Index” in daily patrolling. However, with this method, there is a limitation to the detailed analysis and grasp of Algal bloom because of the limit of Algal bloom's confirmation place or the possibility of human errors, etc.. In this study, in order to make an automatic judgment of the “Algal bloom level” described in "Appearance Algal bloom Index" from digital images, the images of Algal bloom were taken and the water quality in Kasumigaura were analyzed. As a result, the relationship was found between “G-B level” and Chl.a or “Algal bloom level”. In addition, the usefulness of the automatic judgment of Algal bloom level using digital images in which Algal bloom is actually occurring was demonstrated through this study.