Spatial Patterns of Biodiversity and Endemism Across Türkiye: A National-Scale Spatial Autocorrelation Analysis

Abstract

T & uuml;rkiye is one of the biologically richest regions of the temperate zone, yet the national-scale spatial structure of its biodiversity remains insufficiently quantified using formal spatial statistical approaches. In this study, province-level biodiversity indicators derived from the Noah's Ark National Biodiversity Database were analysed to assess whether species richness and endemism exhibit non-random spatial patterns across the country. Global Moran's I, Anselin Local Moran's I, and Getis-Ord Gi* statistics were applied within a GIS framework to identify spatial clustering and biodiversity hotspots. The results indicate statistically significant positive spatial autocorrelation for seven of the nine biodiversity indicators, with the strongest values observed for the rate of endemism and the number of endemic taxa. Vascular plant richness shows marginal evidence of clustering at the 90% confidence level, whereas bird richness does not differ significantly from spatial randomness. High-value clusters are concentrated along the Mediterranean belt, the Eastern Black Sea region, and the Taurus mountain system, whereas comparatively lower biodiversity values occur in several inland provinces. These spatial patterns are interpreted in relation to T & uuml;rkiye's pronounced climatic, topographic, and land-use heterogeneity.