The use of small unmanned aerial systems (sUAS) in aerial mapping applications1 is increasingly being used as an appropriate surveying method in many sectors, particularly for agriculture. Since the use of sUAS is new to many agricultural sector players, it is useful to reflect on the costs and benefits, and related technical and operational challenges, as well as the advantages that present themselves in the practical implementation of this technology.
In Africa, agricultural entrepreneurs are beginning to be exposed to sUAS technology. However, there is currently a lack of evidence of the benefits outweighing costs for emerging drone-based services, which hinders widespread adoption. Published cases of sUAS use in agricultural mapping scenarios have, to date, remained too limited to provide a sufficiently large body of work to claim that the technology has established itself as a widely-accepted surveying method. After providing an overview of the basic characteristics of sUAS-derived mapping products in agricultural settings, this paper presents two case studies to compare the appropriateness and efficiency of sUAS-supported mapping techniques relative to other established terrestrial survey methods. A cost-benefit analysis of sUAS use of in Osona Village Development and Double DV Ranchette projects is used to exemplify the practical potential of UAV-supported mapping technology in agricultural applications.
It should be pointed out that sUAS technology does not replace conventional surveying methods but provides an additional resource complimenting conventional instruments in the surveyor’s equipment inventory, namely total station and global navigation satellite system (GNSS) receivers. Furthermore, the analysis provided in this paper focuses only on those applications, or aspects thereof, in which conventional terrestrial surveys methods are currently accepted as feasible and appropriate. Conventional, manned aerial mapping techniques, LIDAR (light detecting and ranging) surveying and satellite mapping are thus not included in the cost-benefit analysis. Radiometric aspects of sUAS-supported mapping technique have also not been considered in this analysis. This analysis focuses on the spatial or geometric aspects of surveying and mapping.