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

RESEARCH ARTICLE Exploring on the climate regionalization of Qinling-Daba mountains based on Geodetector-SVM model Yufan HuID1,2, Yonghui Yao1*, Zhixiang Kou1,2 1 State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing, China, 2 University of Chinese Academy of Sciences, Beijing, China * yaoyh@lreis.ac.cn Abstract Qinling-Daba Mountains (QDM), which are located in central China, are considered as a sig- nificant climatic boundary delimiting north and south. However, the influence of complex topographic and climatic features makes it challenging to identify the exact location of the boundary, and different scholars delimit the boundary with significant differences. In addi- tion, there is a gradual transition between climate zones, and no real dividing line exists. To explore the climate regionalization of the QDM, we focused on the identification of the transi- tion zone rather than the exact location of the boundary between subtropical and temperate zones. Thus, we proposed a new workflow for climate regionalization based on the Geode- tector-SVM model (a combination of Geodetector and support vector machines). First, we selected the spatial distribution data of six vegetation types (including typical subtropical and temperate vegetation) to represent the spatial distribution of climatic zones. Environ- mental factors (such as topography, temperature, precipitation, and soil) were used as explanatory variables for the spatial distribution of vegetation. Second, using the Geodetec-

tor-SVM model, the distribution characteristics and suitable environment of typical vegeta- tion in different climatic zones are comprehensively explored. By analyzing the multiple boundaries between subtropical and temperate vegetation, the location of the transition zone of the QDM was identified. The results revealed the following: (1) The new workflow for climate regionalization based on the Geodetector-SVM model is powerful for the identifica- tion of the transition zone. The q-statistics are generally greater than 0.35, indicating that the transition zone between subtropical and temperate zones can highly reflect the character of the QDM; (2) From west to east, the transition zone mainly passes through the cities of Heishui County, Kang County, Liuba County, and Yichuan County and is approximately 30 km wide. PLOS ONE PLOS ONE | https://doi.org/10.1371/journal.pone.0241047 November 2, 2020 1 / 16 a1111111111 a1111111111 a1111111111 a1111111111 a1111111111 OPEN ACCESS Citation: Hu Y, Yao Y, Kou Z (2020) Exploring on the climate regionalization of Qinling-Daba mountains based on Geodetector-SVM model. PLoS ONE 15(11): e0241047. https://doi.org/ 10.1371/journal.pone.0241047 Editor: Shamsuddin Shahid, Universiti Teknologi Malaysia, MALAYSIA Received: March 26, 2020 Accepted: October 7, 2020 Published: November 2, 2020 Copyright: © 2020 Hu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and

source are credited. Data Availability Statement: All relevant data are within the paper and its Supporting Information files. Funding: The authors received no specific funding for this work. Competing interests: The authors have declared that no competing interests exist.