Continuous Monitoring for Floating-debris Flux in Rivers with Image-analysis Technique

ABSTRACT

Marine debris with a lot of plastics has become a global and serious environment issue. In particular, a microplastic which is less than 5 mm has been focused over all the world because microplastics with hazardous chemical substance influences on a lot of marine lives. Marine debris are mostly originated from inland and flowed out into the ocean via rivers. Therefore, it is necessary to conduct monitoring of floating-debris flux in rivers.

In this study, we conducted a continuous monitoring of floating-debris flux in rivers using an image-processing technique. For this, we used digital video cameras with visible and near infrared lights. The cameras on the bridge and levee were set toward the normal and diagonal angles to the water surface, respectively. The results indicated that the present method with normal and diagonal angles can detect appropriately the floating litters in the rivers. It is noted that the floating debris flux was dominant in flood conditions.

Key Words: river debris, marine debris, image analysis, continuous monitoring