Predicting the influence of future climate change on the suitable distribution areas of Elaeagnus angustifolia.

Abstract

Climate change significantly affects geographic distribution of plants worldwide. Understanding the influence of climate change on the suitable areas of afforestation tree species in China and taking timely countermeasures are crucial for improving the effectiveness of afforestation. Elaeagnus angustifolia is a good species for ecological restoration of degraded lands and control of desertification. Using MaxEnt and GIS, we predicted the changes of climatically suitable areas of this species under future climate scenarios, based on 182 records from herbaria and published literatures, and 13 climatic factors from BIOCLIM, Holdridge life zone and Kira index. The results showed that the four climate scenarios in 2070s had different effects on the climatically suitable areas of this species. The suitable areas would shrink in the lowest greenhouse gas emission (RCP 2.6) scenario. The shrinking areas were mainly located in the edge of the currently suitable areas in the northwest. The suitable areas would expand in the lower (RCP 4.5), the higher (RCP 6.0) and the highest (RCP 8.5) greenhouse gas emission scenarios. The expanding areas were mainly located in the northwestern arid regions of warm temperate zone, and northeastern sub-humid regions of middle temperate zone. There were obvious expansions in the northern arid and semi-arid regions of middle temperate zone, and southern humid regions of north-subtropical zone under RCP 8.5 scenario. The geographical centroids of future suitable ranges would move with a speed of 6-19 km·(10 a)-1. The altitudinal centroids were predicted to move to lower regions with a speed of 3-20 m·(10 a)-1. The stably suitable areas accounted for 83%-98% of the current distribution ranges of this species, which were generally stable under future climate change scenarios.