*2.1. Study Area*

The GCM include a part of the northeast provinces of Heilongjiang, Jilin, and Liaoning in China and have the largest protected temperate forest in Northeast Asia with many rare animal and plant resources. This area has been a focal point of ecosystem and biodiversity research based on remote sensing applications [27]. The Greater Changbai Mountains (GCM) has a northeast–southwest orientation and extends in the region 38◦46–47◦30 N latitude and 121◦08–134◦ E longitude (Figure 1). It mainly includes parallel fault block mountain areas, such as Changbai, Laoyeling, Zhangguangcailing, and Hadaling. It extends 1300 km from the north to the south and stretches 400 km from the east to the west. The Changbai Mountain is somewhat spindle shaped, and it has a large elevation difference. Its highest peak is located in Jilin Province and is 2670 m high. The total area of the mountains is approximately 2.8 × 10<sup>5</sup> km2. The Changbai Mountain is a treasure trove of world resources as it contains all types of vegetation from temperate to polar types. It covers climatic zones ranging from warm temperate to mid-temperate and from humid to semi humid zones. The mountain also has diverse soil types and complex landform types. The Changbai Mountain has diverse variety and is rich in species. The area mainly has coniferous and broad-leaved mixed forests dominated by Korean pine; coniferous forests dominated by fir, spruce, and larch; and broad-leaved forests in the temperate zone. The Changbai Mountain has a temperate humid monsoon climate and is located on the northeastern edge of the global monsoon climate regions. The region is also affected by the continental climate. Its climate is mainly characterized by long and cold winters and cool and short summers. The climate difference between the north and south is large as the region is spread across nearly 10◦ latitude, and the climate types vary greatly with the terrain because of the influence of altitude.
