Vegetation Structure, Surface-Active Brachyuran Assemblages, and Selected Environmental Conditions in a Replanted Rhizophora mucronata Mangrove Stand

Mangrove replantation is widely implemented as a rehabilitation-oriented response to coastal degradation, yet many replanted stands remain poorly assessed after plantation. This study provides a preliminary dry-season post-plantation habitat characterization of an eight-year-old replanted Rhizophora mucronata stand at Sungai Ujung River, South Sulawesi, Indonesia. Its novelty lies in integrating vegetation structure, surface-active brachyuran taxonomic units, selected surface-water variables, and sediment texture within a single replanted stand where no baseline or long-term monitoring data were available. The final descriptive dataset included seven plots across three transects. Surface-active brachyurans and water-quality variables were recorded across five valid sampling occasions: three spring-tide and two neap-tide occasions. Because tidal period was a sampling-occasion-level condition and temporal replication was limited, spring–neap patterns were interpreted descriptively. Eight surface-active brachyuran taxonomic units comprising 676 individuals were recorded, dominated by Metopograpsus latifrons. Crab abundance, Shannon diversity, and water-quality profiles varied among occasions and plots. All 113 living mangrove individuals were R. mucronata, with established trees, visible seedlings, and scarce poles. Sediment texture ranged from sand-dominated to clay-rich substrates. These findings provide a structured reference point for future monitoring, but do not demonstrate replantation success, recovery trajectory, or functional recovery.