Authors: Stella Todd*, Metropolitan State University Of Denver
Topics: Biogeography, Spatial Analysis & Modeling, Applied Geography
Keywords: biogeographical regions, ecosystems, biodiversity, species richness
Session Type: Paper
Presentation File: No File Uploaded
This paper evaluates biodiversity within geographic entities of similar environmental properties from micro to macro scales. Six large (Omernik) biogeographical regions in Colorado were compared to each other, as were the sub-regions within them. Very small (900m2) ecosystems were compared with large regions and smaller sub-regions. Measurements included species richness and Simpson-Gini diversity. Species redundancy increased from ecosystems to small regions to large regions. Ecosystem variety was moderately predictive of species richness within small regions and was more predictive than area alone. Small biogeographical regions were distinct from one another with respect to Simpson-Gini species diversity along elevation, terrain relief, and climatic gradients using pairwise one-way ANOVA. While small biogeographical regions are nested within large ones by definition, ecosystems are widely dispersed and responsive to local conditions. The same ecosystem may have a substantial contribution of species diversity and/or richness within multiple ecoregions. Because ecosystems and biogeographical regions have consistent environment properties they serve as ontological entities by which to compare species proportions and distributions.