Andik Isdianto, Mark Jonathan Manullang, Oktiyas Muzaky Luthfi, Rudianto, Gilang Rusrita Aida, Nico Rahman Caesar, Desy Arisandi, Rhochmad Wahyu Illahi, Aulia Lanudia Fathah, Alifiulahtin Utaminingsih, Mohammad Maskan, Berlania Mahardika Putri
Industrial land reclamation in the Manyar Estuary, Gresik (Indonesia), is reshaping coastal water quality and management. This study quantifies links between reclamation extent and estuarine water parameters and turns the evidence into practical coastal-planning actions. We analysed a five-year dataset (2020-2024) combining in-situ measurements at 14 stations (depths 0, 1, and 3 metres) with curated secondary records, and tested associations using correlation analysis within an integrated coastal-planning perspective. Turbidity rose from 5.0 to 16.8 nephelometric turbidity units (NTU; standard < 5), salinity from 24.0 to 31.0, and sediment grain size from 0.0180 to 0.0185 millimetres, while dissolved oxygen improved from 4.0 to 6.6; the reclaimed area expanded from 118 to 128 hectares. Exploratory correlation analysis (n = 5) indicated positive associations between reclamation extent and salinity (Pearson r = 0.884) and sediment grain size (r = 0.967), while turbidity increased monotonically with reclamation extent (Spearman ρ = 1.000), though the Pearson association was not statistically supported. Sediment grain size changed marginally (0.0180 to 0.0185 mm) and its correlation with reclamation (r = 0.967) should be interpreted cautiously because the absolute change is very small and uncertainty estimates are not provided. Given the short time series (n = 5) and mixed data sources, these associations should be treated as exploratory and used to prioritize improved monitoring and hypothesis-driven follow-up analyses before detailed management prescriptions are adopted. Copyright: © 2026 The authors. This article is published by IIETA and is licensed under the CC BY 4.0 license (http://creativecommons.org/licenses/by/4.0/).
Department of Fishery and Marine Resources Utilization, Brawijaya University, Malang, 65145, Indonesia; Department of Fisheries Marine Resources Management, Brawijaya University, Malang, 65145, Indonesia; Department of Socio-Economy Fisheries and Marine, Brawijaya University, Malang, 65145, Indonesia; Master Program of Environmental Management and Development, Brawijaya University, Malang, 65145, Indonesia; Doctoral Program in Sociology, Brawijaya University, Malang, 65145, Indonesia; Department of Business Administration, State Polytechnic of Malang, Malang, 65141, Indonesia; Master of Environmental Sciences, Universitas Gadjah Mada, Yogyakarta, 55284, Indonesia
