Turf Algae Monitoring on Artificial Reefs Using Underwater Photography and ImageJ
Received: 21 September 2025 | Revised: 13 January 2026 and 21 February 2026 | Accepted: 23 February 2026 | Online: 4 April 2026
Corresponding author: Andik Isdianto
Abstract
Coral reefs are vital ecosystems that support marine biodiversity and protect shorelines, but face increasing threats from human activities. Artificial reefs have emerged as a restoration tool to enhance ecological functions and provide habitats for benthic organisms. Turf algae, which are among the first to colonize artificial reefs, play a critical role but can inhibit coral recruitment and biodiversity when their growth becomes excessive. This study introduces a data-driven methodology for monitoring turf algae cover, applied at Damas Beach, East Java, using underwater photography and the ImageJ software. The measured turf-algae cover ranged from 12.0% to 33.9% across reef units. Turf algae were higher on sediment-free surfaces, consistent with sediment burial likely associated with lower early algal colonization. These results demonstrate that an ImageJ-based photo-analysis workflow can quantify turf-algae cover consistently and support long-term monitoring of artificial reefs.
Keywords:
artificial reef monitoring, imagej software for reef monitoring, long-term reef management, marine ecosystem restoration, turf algae quantificationDownloads
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Copyright (c) 2026 Yashinta Widiana Jatmiko, Aulia Lanudia Fathah, Muhammad Naufal Eka Putra, Berlania Mahardika Putri, Andik Isdianto
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