Exploring on the climate regionalization of Qinling-Daba mountains based on Geodetector-SVM model

three couples of representative vegetation types met the experimental requirements in this study. The delimitation of transition zone should include more types of vegetation, such as shrubs, meadows, and deciduous forests to produce more convincing results; (3) Other explan- atory variables affect the spatial distribution of vegetation, such as human activities and extreme weather. Therefore, for more credible regionalization, the selection indicators should consider more comprehensive factors. Conclusion The transitional zone between subtropical and temperate zones was identified by the Geode- tector-SVM model based on multiple vegetation-climate indexes, and validation reveals that the transition zone is not only consistent with the distribution of representative vegetation but also similar to the previous climatic boundaries. The Geodetector-SVM model provides good statistical support for the establishment of an index system. The results revealed the following: (1) This paper proposed a workflow for comprehensive physical regionalization and revealed the identification of transition zone rather the division of the boundary can better reflect the transitional character of the QDM and completely reflect the changes in geographical and eco- logical patterns. (2) From west to east, the transition zone mainly passes through the cities of Heishui County, Kang County, Liuba County, Shanyang County, and Yichuan County, and it is approximately 30 km wide. The average annual precipitation is approximately 803 mm, and

the average annual temperature is approximately 9.1˚C in the transition zone. The transition zone acts as a buffer zone, and the characteristics of the climatic environment and vegetation types are gradually transformed from a subtropical zone to a temperate zone in this area. Supporting information S1 File. Veg data supplemental. The file including the data of Plant community survey and the data of Spatial distribution of vegetation. (ZIP) Author Contributions Conceptualization: Yufan Hu, Yonghui Yao, Zhixiang Kou. Data curation: Yufan Hu. Formal analysis: Yufan Hu. Methodology: Yufan Hu. Project administration: Yonghui Yao. Software: Yufan Hu. Visualization: Yufan Hu. Writing – original draft: Yufan Hu. Writing – review & editing: Yonghui Yao, Zhixiang Kou. References 1. Ko¨ ppen W, Geiger G. Das geographisca System der Klimate. Handbuch der Klimatologie;1936. 2. Kottek M, Grieser J, Beck C, Rudolf B, Rubel F. World map of the Ko¨ppen-Geiger climate classification updated. Meteorologische Zeitschrift. 2006; 15(3):259–263 https://doi.org/10.1127/0941-2948/2006/ 0130 PLOS ONE Climate regionalization based on Geodetector-SVM model PLOS ONE | https://doi.org/10.1371/journal.pone.0241047 November 2, 2020 14 / 16