Schisandra sphenanthera is the third-class conservation of wild medicinal species. It is widely distributed in Qinling Mountains. We collected S. sphenanthera samples at 307 sampling points in 19 sampling sites and extracted deoxyschizandrin and γ-schizandrin by high-performance liquid chromatography. We used "fuzzy theory" to determine the association of deoxyschizandrin and γ-schizandrin content and 15 assessment factors, including climate, soil and topographic factors. Then we used the

more »

... m entropy model to determine the weight of each factor. Finally, we estimated the spatial distribution of S. sphenanthera in Qinling Mountains by the weighted average method and GIS spatial analysis. The proportion of unsuitable, suitable and high-suitable habitat for S. sphenanthera in Qinling Mountains was 11.40%, 50.63%, and 37.97%, respectively. The high-suitable habitat are mainly located in southern Shaanxi, eastern Gansu, western Henan, Shennongjia in Hubei, and the surrounding area, with elevation 800 to 2 000 m.This habitat-suitability assessment model based on GIS and fuzzy logic could be used to accurately determine the habitat suitability of S. sphenanthera, quantify the area of suitable habitat and analyze the spatial distribution. This information would supply scientific evidence for the choice of GAP and construction and advice for protection and sustainable utilization of resources.