Abstract:

The genus Rubus included medicinal and edible plants with great economic development potential. Study on climate, topography and soil variables effects for the suitable distribution of these species could provide a valuable reference for resource protection, introduction and utilisation. Using effective distribution data of Rubus and 28 climate, topography and soil environmental variables, the potential suitable distribution of Rubus in China was predicted using the optimized MaxEnt model based on the ENMeval package in R under the current (1970−2000) and future (2021−2040 and 2061−2080) climate conditions. The results showed that after optimization by the ENMeval package, the model’s Akaike information criterion (ΔAICc) was 0, indicating good predictive performance. Elevation, isothermality, the cation exchange capacity of the clay fraction in topsoil (0−30cm), the mean temperature of the wettest quarter and the minimum temperature of the coldest month were the important environmental variables that significantly affected the suitable distribution of Rubus. The highly suitable area for Rubus under the current (1970−2000) climate conditions was 192.72×10⁴km², mainly concentrated in Shaanxi, Guizhou and Fujian. Under the future (2021−2040 and 2061−2080) climate conditions and four greenhouse gas concentration pathways (SSP126, SSP245, SSP370 and SSP585), both the total and highly suitable areas for Rubus were significantly reduced to 52.11%−66.36%, 49.99%−71.61% compared with the current climate conditions, respectively. The reduction mainly occurring in the northwest, north, northeast, the Xizang autonomous region and Yunnan in southwest China. The prediction shows that the suitable area of Rubus will significantly decrease with future climate change. Ex situ conservation measures could be adopted in the predicted reduction areas of Rubus to protect these species.

Key words: Rubus, ENMeval, MaxEnt model, Suitable area, Climate change