Moving north in China: The habitat of Pedicularis kansuensis in the context of climate change.

Pedicularis kansuensis is a poisonous grass and a semi-parasitic plant that has spread rapidly in alpine grasslands in recent years and caused great harm to animal husbandry and the ecological environment. However, little is known about the habitat of P. kansuensis and the key environmental factors that influence its expansion. We assessed the potential impact of climate change on the distribution of P. kansuensis in China under representative concentration pathway (RCP) 2.6 and RCP 8.5 using maximum entropy (MaxEnt) and MigClim for the years 2050 and 2070 and examined key environmental factors affecting P. kansuensis distribution. In total, 118 occurrence points and fourteen selected variables were used for the modeling. The models developed for P. kansuensis showed excellent performance (AUC > 0.9 and TSS > 0.90). The results were as follows. 1) The occupied habitats for P. kansuensis in the four climate scenarios were generally offset in the northward direction. 2) The most important environmental variables influencing the spread of P. kansuensis were altitude, annual precipitation, annual temperature range, precipitation in the warmest quarter and ultraviolet-B radiation seasonality (UVB-2). 3) Under RCP 2.6, the occupied habitat would be increased 0.04% by 2050 and would be increased to 0.51% by 2070. Under RCP 8.5, the average occupied habitat was predicted to increase 0.07% by 2050 and increase to 0.53% by 2070. The increase was relatively higher in the occupied habitats located in the southwestern regions (Sichuan, Xizang and Yunnan) than those in the northwestern regions (Gansu and Xinjiang).