*3.1. Landscape Character Types and Areas at the Regional Scale*

At the regional scale, five variables for 45 landscape indicators were divided into 30,591 grid cells. Eleven landscape character types were classified by the scatter plots and spatial distribution of clusters (Figure 3). Type 3 covered a maximum area of 4363 km2, type 11 covered a minimum area of 549 km2, and the other clusters covered more than 1000 km<sup>2</sup> (Figure 4a). The ratios of the landscape indicators to the landscape character types were expressed by coding as detailed in the materials and methods section. Figures 3 and 4b show that "L3L4, V1V5V8V10, S5, H7 G4" accounted for more than 60% and were prominent characteristics of the types; "{L3L4}, {V4V5V7V8}, {S5S14}, {G1G3G8G12G15G16}" accounted for 30–60% and were typical characteristics; and "(L2L3L4), (V1V3V6V8V7V10V11), (S4S5S6S7S8S11), (G1G4G5G7G9G11G13G14G15G16 G17)" accounted for 10–30% and were

general characteristics. The ratios of the landscape indicators to the landscape character types indicated the common feature of the railway that landform was prominent in or features typical of a plateau lake basin subregion or karst middle mountain platform subregion. The vegetation included various types of needleleaf forests in the subtropical zone, as well as grasslands and steppes in both the subtropical and tropical zones. The hydrology was characterized by plateau lakes and natural rivers where the soil was dominated by red earths, while the geology included various typologies of the Triassic system, Cambrian system, Devonian system, Nanhua system, Mesoproterozoic system, Quaternary system, and Jurassic system.

**Figure 3.** Landscape character types at the regional scale.

**Figure 4.** (**a**) Areas of landscape character types at the regional scale; (**b**) the ratios of landscape indicators to landscape character types at the regional scale.

The MRS tool was used to divide the landscape character areas. To ensure the segmentation effect, the scale, shape, and compactness parameters were set to 200, 0.4, and 0.1, respectively. A total of 98 landscape character areas were divided in eCognition (Figure 5A). Then, 80 landscape character areas were divided after manual adjustment (Figure 5B). The distribution of the landscape character areas in Kunming City and Yuxi City was relatively compact, while the distribution of the areas in Honghe Hani and Yi Autonomous Prefecture and Wenshan Zhuang and Miao Autonomous Prefecture was relatively sparse. The landscape character areas gradually decreased in number from north to south. The landscape character areas were more distributed when closer to an urban area and vice versa. In order to further identify the landscape character of the Yunnan–Vietnam Railway (Yunnan Section), 26 landscape character areas along the railway were selected to be named and described according to the prominent or typical features of the landscape character types and field survey (Appendix A) (Table 3). All of the 26 landscape character areas contained red earths, which was a highly representative landscape character along the railway. According to the landform statistics, seventeen landscape character areas contained plateau lake basin, three landscape character areas contained karst middle mountain platform, and six landscape character areas contained both plateau lake basin and karst middle mountain platform. According to the geology statistics, nine landscape character areas included the Triassic system, six landscape character areas included the Devonian system, three landscape character areas included the Cambrian system, and the others included mixed landscape indicators. In addition, there were several special areas. For instance, the landscape character areas for B5, B51, B54, and B71 were characterized as having urban and lake features, and B27, B73, B74, and B76 were characterized as having karst middle mountain platform and tropical rain forest, grassland, and shrub features.

**Figure 5.** Landscape character areas at the regional scale: (**A**) delineation in eCognition; (**B**) delineation by manual adjustment.


**Table 3.** Descriptions of landscape character areas at the regional scale.


*3.2. Landscape Character Types and Areas at the Corridor Scale*

At the corridor scale, five variables of the 24 landscape indicators were divided into 35,554 grid cells. Combined with the scatter plots and the spatial distribution of clusters, 12 landscape character types were identified (Figure 6A). Type 6 covered a maximum area of 1224.4 km2 and type 7 covered a minimum area of 17.75 km<sup>2</sup> (Figure 7a). Figures 6A and 7b showed that "α4, β1β2β3, γ4γ5, θ2θ4, ε1ε2" were the prominent landscape characteristics of the types, "{α3α4}, {β1β2β3β4}, {γ2γ3γ4γ5}, {θ1θ2}" were typical characteristics, and "(α2α3), (β1β2β3β4), (γ1γ2γ3γ4γ5), (θ1θ2θ3θ5), (ε3)" were the general characteristics (Figure 3). The ratios of the landscape indicators to the landscape character types showed a common feature of the railway, namely, that altitude was prominent in or typical of a middle-high altitude and a high altitude. The slope and aspect were diverse, encompassing flat slope, gentle slope, sunny slope, shady slope, etc. The land use included various types of arable land, built area, and forest land, while the heritage density was characterized by low and medium densities, with zero to four heritage points per square kilometer.

An effective segmentation was received when the parameters for scale, shape, and compactness were set to 100, 0.1, and 0.5, respectively. A total of 63 landscape character areas were divided in eCognition (Figure 6B). Then, 58 landscape character areas were divided after manual adjustment (Figure 6C). The landscape character areas were more distributed when they were closer to an urban area and vice versa. The landscape character areas were named and described by the landscape character types and the field survey (see Appendix B), as shown in Table 4. All of the 58 landscape character areas contained middle–high altitude and high altitude characteristics, which were highly representative landscape characters. Land use was the key variable for dividing the landscape character areas. The five areas containing water landscape characters were located in Dianchi, Fuxian, Yangzonghai, Yilong, and Datunhai Lake; 23 were characterized by forest land, 13 were characterized by arable land and built area types, and the others included mixed types of arable land, forest land, and built area. The landscape character areas for C6, C27, and C45 were characterized by medium- and low-heritage densities, which primarily covered the urban areas of Kunming City and the Kaiyuan and Mengzi County Cities.

**Figure 6.** Landscape character types and areas at the corridor scale: (**A**) landscape character types; (**B**) delineation areas in eCognition; (**C**) delineation by manual adjustments.

**Figure 7.** (**a**) Areas of landscape character types at the corridor scale; (**b**) the ratios of landscape indicators to landscape character types at the corridor scale.

**Table 4.** Descriptions of landscape character areas at the corridor scale.


