2D TRAJECTORY OF PLASTIC DEBRIS IN WAKATOBI SEA AND ITS SURROUNDINGS USING DELFT3D MODEL

• Main Author: Ritista Perdana Atmaja, Rangga
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/42243
• Institution: Institut Teknologi Bandung

Plastic waste can decrease water quality and affect environmental health, economic, dan food chain. In 2017, World Oceans Summit (WOS) announced that Indonesia received the second place world ranking as the biggest plastic producer in the world. It was proven by Jenna Jambeck’s research in 2015 that concludes that Indonesia produced 3.22 million tons of plastic waste yearly. Wakatobi as a well known destination for tourism is affected by the marine debris problem. Study of marine debris’s trajectory using DELFT3D-FLOW was performed to define marine debris distribution. Model inputs include bathimetry, tidal component, surface wind velocity and direction, and initial position of marine debris particles. The aim of this study is to investigate marine debris‘ trajectory in both boreal summer and boreal winter in Wakatobi sea that is divided into continuous (December 2017 - April 2018) and discontinuous particles (June 2018 – September 2018). Continuous particles represent plastic debris from local residents in Wangi-wangi Island, Kapota Island, Kaledupa Island and Tomia Island. While discontinuous particles represent plastic debris from Banda sea and Flores sea. Wakatobi has many area with coral reef, it affects ocean current also meridional tide and seasonal wind that may affect particle’s trajectory. Daily model shows particle’s movement is close – disperse because of the tide. Both boreal summer and boreal winter have their own distribution area of marine debris depending on its wind direction. In boreal winter, marine debris are found in north, east and south of Wakatobi Sea while boreal summer are found in west and south of Wakatobi Sea. From 6 source points of marine debris, there are 2 source points in which particles move along the observation area: Wangi-wangi and Kapota. Each of them contributes about 264 kilograms and 49.5 kilograms of potential marine debris that is transported into the shore. But, particles from Banda sea and Flores sea only move close to their source area. It means, continued particles from land are more responsible on marine debris impact in Wakatobi sea than discontinued particles in Banda Sea and Flores Sea. Particles which are released in boreal summer move in the west of Wakatobi sea and become marine debris. Whereas, particles that are released in boreal winter move in the west of Wakatobi sea and become marine debri. This proves Wakatobi’s resident’s statement. In boreal summer, marine debris are found in west of Wakatobi sea while in boreal winter marine debris are found in east of Wakatobi sea.