DHIs clusters

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Header files (.hdr) are stored uncompressed in the same folder as the compressed (.zip) files. They must be in the same folder as the uncompressed (.dat) files for use.
All datasets use the WGS84 global coordinate system and are produced at a spatial resolution of 0.00833 degrees (approximately 1 km). We provide a brief description of the individual datasets in this file. More information can be found in the manuscript.

SOURCE

DESCRIPTION

# Global DHI Clusters
(files = DHI_global_clusters_14c_sv20.dat; DHI_global_clusters_40c_sv20.dat):
  • These datasets are the final outputs of two-stage clustering using inputs of global Dynamic Habitat Index (DHI) variables of annually integrated cumulative, minimum and variation of fPAR (fraction of photosynthetically active radiation) and latitude (degrees from equator):
  • DHI_global_clusters_14c_sv20.dat is a 14-cluster output, developed for direct comparison with the 14 global biomes produced in 2001 by Olson et al. (https://www.worldwildlife.org/publications/terrestrial-ecoregions-of-the-world). Colors were assigned relative to average DHI variables for each cluster, such that green clusters indicate relatively higher productivity and lower seasonality (e.g., rainforests), blue areas indicate higher seasonality and lower productivity (e.g., boreal forests), and red areas indicate low productivity and low seasonality (e.g., deserts).
  • DHI_global_clusters_40c_sv20.dat is a 40-cluster output. Cluster validity metrics stabalized at around 40 clusters, suggesting that this may be the maximum number of meaningful DHI-derived clusters. No color assignments have been made for this output.
  • Both outputs have been sieved to an effective minimum mapping unit of approximately 20 sq.km.
# Global DHI Pre-clusters
(file = DHI_global_precluster_867c.dat):
  • This dataset is the output of the initial k-means++ pre-clustering of global Dynamic Habitat Index variables of annually integrated cumulative, minimum and variation of fPAR (fraction of photosynthetically active radiation) and latitude (degrees from equator). The centroids of the four variables associated with this layer were used as an input to agglomorative hierarchical clustering (stage two), and each of the 867 pre-clusters were assigned to a final cluster based on their hierarchical groupings. This product has not been sieved (minimum mapping unit is approximately 1 sq.km.) and this is the most appropriate layer for users if they wish to regroup or assign clusters themselves.
# Species Richness datasets
(files = richness_amph_all_spp_1km.dat; richness_bird_all_spp_1km.dat; richness_maml_all_spp_1km.dat; richness_overall_1km.dat):
  • Species richness datasets covering amphibians, birds, and mammals were derived from species range maps available through the International Union for the Conservation of Nature (http://www.iucnredlist.org/), and BirdLife International (see Schipper, J. et al. 2008. The Status of the World’s Land and Marine Mammals: Diversity, Threat, and Knowledge. Science).
  • All range maps were converted to rasters with 1-km spatial resolution, matching the native resolution of the MODIS Dynamic Habitat Index datasets, and species richness maps were produced by counting a species as present if any part of the grid cell was within the species’ range polygon.
  • Overall species richness (richness_overall_1km.dat) was calculated as the sum total of species richness of amphibians, birds and mammals