Increasing water turbidity impact on the rich biodiversity area of Berau Estuary and Kakaban-Derawan Islands Andi Egon (a,b*), Faruq Khadami (a,b), Karina Aprilia Sujatmiko (a,b), Farrah Hanifah (1) and Ayi Tarya (1,2)
a. Oceanography, Faculty of Earth Sciences and Technology, Bandung Institute of Technology (ITB), Indonesia,
b. Centre for Coastal and Marine Development, Bandung Institute of Technology (ITB), Indonesia
*aegon[at]itb.ac.id
Abstract
Turbidity plays a crucial role in the coastal and marine environment. Global climate change, which encompasses heightened precipitation, severe weather occurrences, and elevated cloudiness, can have a profound impact on coastal and marine biodiversity, namely coral reefs. The study region is located on the Berau continental shelf (BCS) on Kalimantan^s eastern coast in Indonesia. The ocean receives its turbid water primarily from the Berau estuary. The BCS region boasts a high abundance of coastal and marine biodiversity, including various fish species, green turtles, manta rays, seagrass ecosystems, and coral reefs. Notably, the famous Derawan Islands, situated about 75 km from the shore, are particularly rich in these natural wonders. The BCS, located in the central Indo-West Pacific, is a part of the Coral Triangle. In terms of biodiversity, it is the second-highest ranking area in Indonesia, after the Raja Ampat Islands in Papua. Experts estimate the area to contain a minimum of 500 species. The research region underwent an evaluation of potential future scenarios in relation to global climate change, utilising the Delft3D-Flow model. This model simulated scenarios of heightened precipitation intensity using the estimation rate derived from the IPCC Sixth Assessment Report. This text provides an examination of how global climate change affects the Berau Coastal System (BCS). The main focus is on determining and measuring the rise in turbidity that originates from the Berau estuary and spreads over the open ocean, including its influence on the vulnerable biological receptors in the Derawan Islands. Subsequent analysis will utilise this assessment to identify the most significant alteration in land use in the Berau Estuary upstream, with the aim of mitigating the adverse effects of global climate change on the BCS coastal and marine environment.
