Integrating the third dimension into the concept of urban ecosystem services: A review

The spatial configuration of urban environments and its impact on local and global ecological functions were the subject of recent urban ecosystem service (UES) research projects. The outcomes of these projects with respect to the data they used, however, mainly consisted of two dimensions (2D). Studies that assess aspects of the third dimension (3D) of UES - such as height, volume and shadowing effects - were absent. The objective of this paper is to contribute to a better understanding of the local ecological functions based on knowledge of three-dimensional UES. 298 articles were selected for in-depth critical analyses. The technical and computational approaches for extracting urban 3D structures and 3D structures of vegetation were the focus of the reviewed literature. Authors' affiliations would be a better indicator for assessing the spatial distribution of articles. Uneven distribution of knowledge among countries is related to the technical and scientific advancement of countries. There was a shift in the sub-theme of reviewed publications discussing the concept of ecosystem services in the first few years, while later researchers' interests moved towards UES and adaptation of cities to the changing climate. Further studies should progress in the development of both 3D data and results. Implementing 3D data and results helps to better understand the coupling of humans and their environs. It will be then a critically important step toward developing ecologically friendly cities.