Taking 109 gymnosperm species in China as a case, the uncertainty and risk of losing habitat areas of gymnosperm species under future climate conditions were investigated via representative concentration pathways climate change scenarios, fuzzy set classifications and Monte Carlo techniques. Under nonrandom climate change scenarios, the richness of 109 species increased in the partial locations of northwestern and northeastern China and declined in the partial locations of eastern and central and southeastern China; the numbers of species that losing <20%, 20-40%, 40-60%, 60-80%, and over 80% of their current habitat areas were ~33-49, 36-40, 11-24, 7-9, and 2-8, respectively; ~99-105 species occupied over 80% of their total suitable areas and ~4-9 species occupied 60-80% their total suitable areas. Under random climate change scenarios, the number of species that losing various level of the habitat areas declined with enhancing probability; with a probabilities of over 0.6, the numbers of species that losing <20%, 20-40%, 40-60%, 60-80% and over 80% of their current habitat areas were ~19-28, 3-19, 0-3, 1-2, and 9-14, respectively, and the numbers of species that occupying ~20%, 20-40%, 40-60%, 60-80%, and over 80% of their total suitable areas were ~9-14, 4-11, 2-6, 1-3, and 34-45, respectively. Approximately 41% of 109 species will face extinction risks from climate change; the losing habitat areas in future climate condition will cause the varying of coniferous forest composition and the losing of ecosystem service related to the species; the uncertainty of losing distribution areas for species should not be ignored.
Keywords: Climate change; Gymnosperms; Monte Carlo methods; Risk; Tree species; Uncertainty.