Land suitability assessment for mangrove-based silvofishery in North Sumatra, Indonesia

Abstract. Risdayanti, Basyuni M, Aththorick TA. 2026. Land suitability assessment for mangrove-based silvofishery in North Sumatra, Indonesia. Asian J For 10 (1): r100130. https://doi.org/10.13057/asianjfor/r100130. Silvofishery integrates mangrove conservation with brackish-water aquaculture and is increasingly promoted as a sustainable alternative to conventional pond systems in Indonesia. However, site-specific evaluations of biophysical land suitability remain limited. This study aimed to assess land suitability for mangrove-based silvofishery in Pasar Rawa Village, Langkat District, North Sumatra, Indonesia, by integrating vegetation structure, soil characteristics, water quality parameters, and a weighted scoring land-evaluation approach. Mangrove vegetation was surveyed using three perpendicular transects with 21 nested plots (10×10 m trees; 5×5 m saplings; 1×1 m seedlings). Soil (0-30 cm) and water samples were collected from the inlet, outlet, and pond interior compartments. Five mangrove species were recorded, dominated by Rhizophora apiculata and Sonneratia alba. Total densities reached 257.1 ind/ha (trees), 3,219.1 ind/ha (saplings), and 833.3 ind/ha (seedlings), indicating active regeneration. Water quality showed a mean temperature of 28.6°C, salinity of 15.0 ppt, pH of 6.5, and dissolved oxygen of 8.7 mg/L, within acceptable ranges for silvofishery. Soil analysis revealed moderately acidic conditions as the primary limiting factor. The weighted scoring system yielded a suitability index of 75.75%, classifying the area as Highly Suitable (S1). Acidic soil pH and suboptimal stand density were identified as manageable constraints. These findings provide a practical decision-support framework for restoration-based silvofishery planning and support evidence that maintaining mangrove cover does not compromise aquaculture productivity.