Synergizing IoT, AI, and blockchain for smart agriculture: Challenges, opportunities, and future directions

The integration of the Internet of Things (IoT), blockchain technology (BT), and Artificial Intelligence (AI) is transforming agriculture into a smart, data-driven system designed to enhance productivity, transparency, and automation. Population growth and limited resources make these technologies increasingly critical, especially in regions with scarce water, nutrients, or fertile soil. IoT provides real-time monitoring and physical data collection through sensors and edge devices, BT ensures data security, traceability, and transparency across supply chains, while AI enables predictive analytics and automated decision-making, reducing direct farmer intervention. This systematic literature review is focusing on the IoT implementations in the agriculture ecosystem, with the sole aim of increasing agricultural productivity and efficiency. Furthermore, it analyzes the interplay of IoT, AI, and BT in agriculture, with the emphasis on the measurable impacts, security of communication protocols, socio-technical implications, and automation and decision-making, among others. Despite their promise, integration faces notable barriers such as data privacy, interoperability, real-time processing, and implementation costs. Using the PRISMA framework, 35 studies were selected from an initial pool of 977 articles published between 2019 and 2025. A rigorous quality assessment extracted insights on integration strategies, technical limitations, and practical applications. The review highlights opportunities and challenges in adopting IoT, AI, and BT for sustainable smart agriculture. It concludes with recommendations for researchers, policymakers, technology developers, and practitioners to address current gaps, strengthen security and interoperability, and guide future advancements toward resilient and efficient agricultural systems.