Tracking shifts in forest structural complexity through space and time in human-modified tropical landscapes

Habitat structural complexity is an emergent property of ecosystems that directly shapes their biodiversity, functioning and resilience to disturbance. Yet despite its importance, we continue to lack consensus on how best to define structural complexity, nor do we have a generalised approach to measure habitat complexity across ecosystems. To bridge this gap, here we adapt a geometric framework developed to quantify the surface complexity of coral reefs and apply it to the canopies of tropical rainforests. Using high-resolution, repeat-acquisition airborne laser scanning data collected over 450 km2 of human-modified tropical landscapes in Borneo, we generated 3D canopy height models of forests at varying stages of recovery from logging. We then tested whether the geometric framework of habitat complexity – which characterises 3D surfaces according to their height range, rugosity and fractal dimension – was able to detect how both human and natural disturbances drive variation in canopy ..., For details of the methods used to generate the data see Rosen et al. (2024) Ecography, 10.1111/ecog.07377 , , # Tracking shifts in forest structural complexity through space and time in human-modified tropical landscapes

```
data_code_archive/
|-----data/
| |-----new_standardised_chms/ # <- ready to use canopy height models.
| |-----sensitivity_polygons_2023/ # <- shapefile containing the polygons needed for the sensitivity analysis.
| |-----SAFE forest classification/ # <- raster and .xlsx file classifying SAFE landscape by habitat type.
| |-----Danum_boundary_extent/ # <- shapefile of Danum CHM boundary extent.
| |-----SAFE_boundary_extent/ # <- shapefile of SAFE CHM boundary extent.
| |-----Maliau_boundary/ # <- shapefile of Maliau CHM boundary extent.
| |-----whole_landscape/ # <- shapefile containing gridded polygons used in the whole landscape analysis.
| |-----Land_use_gradient/ # <- shapefile containing polygons used in the space-for-time analysis.
| |-----other_metrics/ # <- ...