Conjoining Trees for the Provision of Living Architecture in Future Cities: A Long-Term Inosculation Study

Abstract

Faced with the environmental challenges posed by climate change, architects are creating nature-based solutions for urban areas, such as transforming living trees into artificial architectural structures. In this study, we have analyzed stem pairs of five tree species conjoined for more than eight years by measuring the stem diameters below and above the resulting inosculation and by calculating the respective diameter ratio. Our statistical analyses reveal that Platanus x hispanica and Salix alba stems do not differ significantly in diameter below inosculation. However, in contrast to P. x hispanica, the diameters of the conjoined stems above inosculation differ significantly in S. alba. We provide a binary decision tree based on diameter comparisons above and below inosculation as a straightforward tool for identifying the likelihood of full inosculation with water exchange. Moreover, we have compared branch junctions and inosculations by means of anatomical analyses, micro-computed tomography, and 3D reconstructions showing similarities in the formation of common annual rings that increase the capacity for water exchange. Due to the highly irregular cell arrangement in the center of the inosculations, cells cannot be assigned clearly to either of the stems. In contrast, cells in the center of branch junctions can always be attributed to one of the branches.

Modeling the Geometry of Tree Trunks Using LiDAR Data

“…Digital Twins (DT) are virtual representations of real-world objects [1]. Digital twins can enhance the performance of thematic systems such as City Information Modeling (CIM) [2], Building Information Modeling (BIM) [3], Land Information Modeling (LIM) [4], and Tree Information Modeling (TIM) [5]. These systems support the real-time monitoring and management of spatial objects to achieve sustainable development in a rapidly changing world [6,7].…”

“…Digital twin models recognize the importance of vegetation and trees not only in urban spaces. Real-world trees and forests are represented with the use of TIM [5,13,31] and Forest Digital Twin (FDT) models [8,13]. Based on the CityGML standard, trees can be modeled at LOD0 through LOD4 level of detail [32][33][34][35].…”

Accurate Calculation of Upper Biomass Volume of Single Trees Using Matrixial Representation of LiDAR Data

“…A Light Detection and Ranging (LiDAR) system is considered to be the main data source of a Digital Surface Model (DSM) and Digital Twin (DT), which characterize virtual representations of real-world features [1]. Indeed, DSM and DT can improve the realization of thematic systems such as City Information Modeling (CIM) [2], Building Information Modeling (BIM) [3], Land Information Modeling (LIM) [4], and Tree Information Modeling (TIM) [5]. Furthermore, although the volume of LiDAR data is large, it has been popularly utilized in Geographic Information Systems (GIS), forest monitoring, and decision-making.…”

A circuit analogy based girth growth model for living architecture design

“…In this light, the creation of living architecture by shaping and merging trees has been adopted by architects and designers worldwide in recent decades [5][6][7][8][9] (figure 1d). This approach has been termed 'Baubotanik' in the context of scientific research, which started in 2007 at the University of Stuttgart, Germany [10][11][12][13][14][15]. The shaping of trees and their joining by inosculation have been used for centuries in horticulture and historical forms of architecture [16].…”

“…For example, living root bridges are functional load-bearing structures grown from Ficus elastica roots by rural Khasi and Jaintia communities in Meghalaya (India) (figure 1 a ). Formed without the tools of modern engineering design, they are a unique example of vernacular living architecture [15,17,18]. Inosculation is the process of intergrowth between two or more plant roots, branches or stems.…”