An Empirical Juridical-Blockchain Valuation Model for Dammar Resin Supply-Chain Finance and Customary Rights Enforcement in Pesisir Barat

Background: Smallholder producers of dammar resin in Pesisir Barat encounter chronic financing constraints because the market cannot reliably value a commodity whose quality is tied to volatile maritime logistics and fragmented customary land rights. Objectives: This study aims to construct a rigorously validated valuation model that (i) quantifies total supply-chain cost under realistic 3T (tertiary, tropical, remote) logistics conditions, (ii) embeds Indonesian Civil Code (KUHPerdata) provisions on contracts, obligations, and remedies, and (iii) operationalises the model within a blockchain-based smart-contract architecture that leverages tamper-proof oracles for weather, temperature, and fuel price. Methods: High-frequency GPS traces, vessel fuel meters, and on-board temperature loggers were collected from 124 voyages (2022-2024). A mixed-integer linear programming (MILP) formulation estimated cost C = Σ_i (c_i^{fuel}·F_i + c_i^{labour}·L_i + c_i^{storage}·S_i) subject to constraints on travel time, speed limits, and storage-temperature deviation. Legal clauses derived from Articles 1320, 1338, and 1243-1245 KUHPerdata were coded as Solidity functions; BMKG weather data and IoT temperature feeds served as oracles triggering force-majeure and SLA breach penalties. Results: Sensitivity analysis shows a 10 % increase in fuel price raises total cost by 8.4 % (95 % CI: 7.9-8.9 %); a 1 degC rise in storage temperature elevates spoilage risk by 14.7 % (CI: 13.8-15.6 %). Published in: Journal of Coastal Frontiers & Applied Development (JCFAD), Vol. 1 No. 1 (2026), pp. 1–12. Official publisher: PT CHAIN ASIA CONECT Research & Development Division.