Mapping the potential distribution suitability of 16 tree species under climate change in northeastern China using Maxent modelling

Knowledge on the potential suitability of tree species to the site is very important for forest management planning. Natural forest distribution provides a good reference for afforestation and forest restoration. In this study, we developed species distribution model (SDM) for 16 major tree species with 2,825 permanent sample plots with natural origin from Chinese National Forest Inventory data collected in Jilin Province using the Maxent model. Three types of environmental factors including bioclimate, soil and topography with a total of 33 variables were tested as the input. The values of area under the curve (AUC, one of the receiver operating characteristics of the Maxent model) in the training and test datasets were between 0.784 and 0.968, indicating that the prediction results were quite reliable. The environmental factors affecting the distribution of species were ranked in terms of their importance to the species distribution. Generally, the climatic factors had the greatest contribution, which included mean diurnal range, annual mean temperature, temperature annual range, and iosthermality. But the main environmental factors varied with tree species. Distribution suitability maps under current (1950 - 2000) and future climate scenarios (CCSM4-RCP 2.6 and RCP 6.0 during 2050) were produced for 16 major tree species in Jilin Province using the model developed. The predicted current and future ranges of habitat suitability of the 16 tree species are likely to be positively and negatively affected by future climate. Seven tree species were found to benefit from future climate including Betula costata, Fraxinus mandshurica, Juglans mandshurica, Phellodendron amurense, Populus ussuriensis, Quercus mongolica and Ulmus pumila; five tree species will experience decline in their suitable habitat including B. platyphylla, Tilia mongolica, Picea asperata, Pinus sylvestris, Pinus koraiensis; and four (Salix koreensis, Abies fabri, Pinus densiflora and Larix olgensis) showed the inconsistency under RCP 2.6 and RCP 6.0 scenarios. The maps of the habitat suitability can be used as a basis for afforestation and forest restoration in northeastern China. The SDMs could be a potential tool for forest management planning.