Socioeconomic potential of seaweed aquaculture in the Mekong River Delta, Vietnam: An integrative review.

Seaweed aquaculture is increasingly promoted within blue economy strategies, but evidence for the Mekong River Delta (MRD), Vietnam, remains fragmented. This PRISMA-informed narrative integrative review screened 460 records after duplicate removal and retained 85 evidence sources. The synthesis compared species suitability, farming systems, value chains, economic evidence, and governance constraints. Gracilaria tenuistipitata had the strongest support for brackish shrimp-pond integration; MRD studies reported standing biomass of 2.13-11.78 t fresh weight ha-1 and associations with higher shrimp yield and profit. Kappaphycus, Eucheuma, Ulva, and Caulerpa required site- or market-specific validation. Shrimp-seaweed IMTA was better aligned with variable salinity than near-shore carrageenophyte systems, whereas IMTA-RAS remained pilot-scale and capital-intensive. Reported NPV and IRR values were too heterogeneous for valid pooling, and no standardized MRD-specific estimates were available. Thus, evidence supports selected pathways, particularly Gracilaria integration, but not a mature or quantitatively documented MRD-wide sector.