One of the key-research topics in landscape ecology is the analysis and characterization of landscape pattern and structure. A description of these two features is commonly achieved through derivation of various metrics (e.g. Contagion, Dominance or Fractal Dimension) for the assessment of landscape connectivity, fragmentation and patch shape complexity. Up to now, only very few analyses in landscape ecology have been carried out on the basis of airborne laser scanning (ALS) data, while the majority is based on either aerial or satellite based imagery supported by conventional field survey. However, airborne and space borne images exhibit a critical drawback in comparison to laser measurements. Images can not display information from below the canopy surface, as the measurement method is not able to penetrate it. Consequently, the derivation of landscape metrics from such data is merely 2D. It can not account for the vertical structure of vegetation, a key element in forestry and the assessment of structural diversity and, as such, landscape ecology. The laser pulses, on the other hand, are able to penetrate through little gaps in the canopy surface and can provide information on the vertical and horizontal distribution of vegetation. The aim of this study is to make use of the 3D information and penetration capability of ALS for the derivation of novel landscape metrics. The presented approach exploits the collected information about the vegetation layer structure in order to describe not only if two landscape patches are connected, but how this connection is composed in terms of vertical structure of the plants building the patches. It therefore integrates knowledge of under storey or herbaceous vegetation into the shape metrics. Additionally, 3D shape metrics that relate the surface of a patch or corridor canopy surface to its enfolded volume are introduced. In this way, information about the three-dimensional interconnection of adjacent landscape patches is obtained.
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