## 3 Results and Discussion  
### Construction of Complex Ecospatial Network  
First, we extracted the ecological source. A total of 143,524 ecological source patches were obtained after screening, including 33,517 forest land ecological source patches, 17,084 shrub forest ecological source patches, 58,772 grassland ecological source patches, 25,103 river and canal ecological source patches, 7645 lake ecological source patches, and 1403 reservoir ecological source patches. The distribution of ecological source patches in the study area is shown in Figure 2.  
The screening results of ecological source patches show that the ecological source patches in the study area are mainly distributed in the northeast and less distributed in the southwest, which indicates that the ecological background in the northeast of the study area is better, while the southwest needs to be optimized. In terms of the distribution area, the ecological source patches are mainly woodland and grassland, which are mainly distributed in the northern and central parts. Second, we constructed the cumulative resistance surface. According to the research purpose and the basic situation of the study area, this paper selected elevation, slope, NDVI, NDWI and land use type as the factors to construct the ecological resistance evaluation system. The results are shown in Figure 3. Analysis of the evaluation results of each ecological resistance factors shows that the western and central parts of the study area have higher elevations, while the northern and eastern parts are lower; the slope range is between 0 and 76.7\({}^{\circ}\), with a higher slope in the north and larger overall undulation. Analysis of the evaluation results of each ecological resistance factor shows that the NDVI value is lower and NDWI value is higher in the west and south, such as the area near Alashan League, and the NDVI value is higher and NDWI value is lower in the north and east, such as the area near Hulunbeier City. The northern part is dominated by cultivated land and woodland, the central part is dominated by grassland and water, and the western part is dominated by unused land. This paper used ArcGIS to assign the ecological resistance value of each ecological resistance factor according to the grading standard in Table 1. We then used the grid calculator to superimpose the evaluation results of each factor to obtain the comprehensive evaluation result and used the Cost-Distance module to obtain the cumulative resistance surface. The results are shown in Figure 4.  
According to the resistance surface data, the ecological resistance value in the study area is between 3 and 27. The low resistance values in the areas near Tongliao City and Hulunbuir City in the north indicated relatively low ecological resistance, while the high resistance values in most areas in the west indicated higher ecological resistance. Finally, based on the obtained ecological source patches and cumulative resistance surfaces, the ecological nodes and ecological corridors in the study area were extracted by using the Cost-Path model, and a complex ecos spatial network was constructed, as shown in Figure 5. A total of 861 ecological nodes and 1519 ecological corridors were extracted. Figure 2: Distribution of ecological source patches in the study area. Figure 3: Ecological resistance factor in the study area.