Systematic synthesis of the notion of scale levels and digital representation in the application of 3D geospatial technology for virtual forests

Abstract. In recent years, novel 3D reconstruction methods have been developed to enhance traditional image-based point cloud generation techniques, leading, among other things, to the emergence of the concept of virtual forests. However, within the forestry domain, this concept is still somewhat ambiguous and may carry different meanings depending on the context of its implementation. In this paper, we identify the need to consolidate existing notions of virtual forests and aim to present a unified definition from a geomatics perspective. To this end, we introduce two concepts: a sensor-focused Level of Scale (LoS) and a data-focused Level of Detail (LoD). For the latter, which draws inspiration from existing definitions in CityGML, an additional data format dimension has been incorporated. A numerical analysis was conducted to highlight the importance of data representation and scale. While the results in this paper are not intended to establish a standard—achieving such would require much greater effort in the future—they hopefully provide a foundation for establishing a standard in 3D vegetation mapping and representation that can be practically applied within the forestry domain.