Spatial Distribution Modelling of Kobresia pygmaea (Cyperaceae) on the Qinghai-Tibetan Plateau

Kobresia pygmaea Willd. dominates the alpine meadow ecosystem on the Qinghai-Tibet Plateau. Knowledge of this species’ distribution and ecological environment could provide valuable insights into the alpine ecosystem and key species living there, support species and ecosystem conservation in alpine regions, and build on species origin and evolutionary research. To avoid modelling uncertainty encountered in a single approach, four species distribution model algorithms (Surface Range Envelope (SRE), Generalized Linear Model (GLM), Generalized Boosted Regression (GBM) and Maximum Entropy (MAXENT)), were used to simulate the distribution of K. pygmaea based on occurrence samples that were verified using DNA sequencing techniques. Species distribution modelling revealed a vast distribution region of K. pygmaea in the northern Tibetan Highlands and alpine meadows in the southern and eastern declivity of the plateau. A high evaluation performance was found for the GLM, GBM and MAXENT models. Different potential range size patterns for the four models were found between 374340-482605 km² (average = 421591 km²). Precipitation during growing seasons was found to be the dominant factor accounting for the distribution, consistent with patterns of heat and water patterns conditions of alpine ecosystems on the plateau. Species distribution models provide a simple and reliable approach to simulating the spatial patterns of species inhabiting the Qinghai-Tibet Plateau.