Blockchain Technology for Sustainable Supply Chain Transparency: Enhancing Traceability and Scope-3 Carbon Accounting in Agricultural SME Exports

Accurate Scope-3 greenhouse gas accounting across upstream agricultural supply chains remains a primary bottleneck for small and medium-sized enterprise (SME) exporters. This study examines how blockchain-enabled distributed ledger technology (DLT) combined with Internet of Things (IoT) sensors enhances supply chain transparency, fair-trade compliance, and Scope-3 carbon accounting precision among agricultural SME exporters. Utilizing a mixed-methods structural equation modeling (PLS-SEM) framework with primary survey data from 520 agricultural SME exporters across Southeast Asia and Europe in 2026, we demonstrate that blockchain adoption increases Scope-3 carbon accounting accuracy to 94.8% while reducing annual third-party verification costs by 66.5%. Hypothesis testing confirms that immutable traceability significantly elevates buyer trust (beta = 0.512, p < 0.001) and supports an average export price premium capture of 14.2% in European import markets. The paper concludes with a technological deployment roadmap for SME cooperatives.