Systematic Literature Review: Application of Unmanned Aerial Vehicle in Agriculture
Thinley Gyeltshen, Kinzang Thinley, Pema Yangdon, Sherab Lhamo, Nangsel Tshomo, Tshering Penjor , Domang and Tenzin Rabgay
https://doi.org/10.55925/btagr.26.9109
ABSTRACT
In recent years, the application of Unmanned Aerial Vehicle (UAV) or drone technology in agriculture has gained popularity. However, in Bhutan, its application is far beyond reach. This systematic literature review synthesizes research on UAV applications in agriculture following PRISMA 2020 guidelines. From an initial 300 records (sourced from Google Scholar, Sci-Hub, and printed literature), 138 peer-reviewed studies met the inclusion criteria and were catalogued in Zotero. Findings are organized into five primary domains, which include crop monitoring and management, agrochemical spraying, crop damage assessment, surveying and mapping, and phenotyping, each encompassing specific secondary themes. Compared with satellites, manned aircraft, and ground systems, UAVs provide higher spatial and temporal resolution, operational flexibility, and cost-effectiveness, leveraging RGB, multispectral, hyperspectral, LiDAR, and thermal sensors. Empirical evidence demonstrates UAV utility for soil nutrient estimation, early pest and disease detection using vegetation indices (e.g., NDVI), precision spraying, rapid damage assessments, high-accuracy mapping, and enhanced phenotyping and yield estimation when combined with machine learning. Notable limitations include short flight time, regulatory constraints, weather sensitivity, and challenges in scaling plot-level results regionally. A key research gap identified is the absence of standardized, scalable methodologies and multi-location validation to translate plot-level UAV findings into reliable regional monitoring systems.
Keywords: Remote sensing; UAVs; UAS, Agriculture; Application