Modeling habitat suitability of Pinus densiflora in response to climate change in the Korean peninsula and East Asia

Thesis (Master's)--University of Washington, 2012The current and future climate suitability of Pinus densiflora in the Korean peninsula, Japan Isles, and parts of northen China was modeled using Random Forest predictors. Pinus densiflora is among the tree species with highest conservation priorities for its historical and cultural importance but distribution of the species is rapidly declining in Korean peninsula. A bioclimate envelope model was built on current spatial presence/absence data of the species from digital forest map of South Korea from Korean Forest Service and high definition digital climate data from 2010. Overall the pattern of predicted current habitat in the region was well matched with existing atlases and literature on Pinus densiflora. Area under the Receiver-Operating Characteristic Curve (AUC) value of the prediction was 0.86 and Cohen's Kappa value was 0.51. The future suitable habitats of the species were predicted by the model at two different resolution, 270 m x 270 m and 1 km x 1 km. The finer resolution maps predicted futures in two IPCC climate change scenarios A1b and A2a. The coarser resolution maps predicted future habitat of the species in a broader extent which covers Northeast Asia with three IPCC climate change scenarios A1b, A2a, and B2a. Overall, thirteen projected climate datasets from six different general circulation models under the three different emission scenarios were used for predicting future habitat suitability in response to climate change in the region. At both resolutions, the model predicted that Pinus densiflora will expand its range northward, although the area of distribution will decrease 20 ~ 50 %. This tendency is reinforced with more dramatic predictions of climate change. The predicted climate niches of Pinus densiflora suggest that precipitation can affect to the species distribution as well as temperature. This result contrasts past predictions that the distribution of the species is governed only by temperature. A preliminary analysis indicates that biotic factors such as pine wilt disease can also influence the distribution of this species. This result suggests that adaptive pest management strategies are likely to be critical for preserving suitable habitats for Pinus densiflora in Korean peninsula in a changing climate