## 3 Results
### Analysis of the Spatial Distribution of Abandoned Farmland
#### 3.5.2 Feature Analysis of Abandoned Farmland  
The slopes in the study area were divided into six slope ranges: 0-5\({}^{\circ}\), 5-10\({}^{\circ}\), 10-15\({}^{\circ}\), 15-20\({}^{\circ}\), 20-25\({}^{\circ}\), and 25\({}^{\circ}\) or more, at fixed intervals of 5\({}^{\circ}\). The area of land abandonment  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Analysis Method** & **Dataset** & **Overall Accuracy** & **Kappa Coefficient** \\ \hline NDVI difference & GF-6 dataset & 78.93\% & 0.58 \\ NDVI difference & Fusion dataset 1 & 93.43\% & 0.87 \\ NDVI difference & Landsat dataset & 64.91\% & 0.30 \\ SVM & Fusion dataset & 83.94\% & 0.68 \\ \hline \hline \end{tabular} \({}^{\dagger}\) NDVI time series dataset fused based on GF-6 and Landsat 8 data.  
\end{table}
Table 5: Overall accuracy and Kappa coefficient of results using different extraction methods with different data.  
Figure 13: Nuclear density profile and high-density sample areas. (**a**) Sample area (a) in high-density, (**b**) Sample area (b) in high-density, (**c**) Sample area (c) in high-density.  
patches within each slope range and the proportion in the total study area were counted. The proportion of abandoned farmland to all farmland and the abandonment rates at different intervals are shown in Figure 14a.  
The DEM in the study area was divided into four categories, with 400 m, 600 m, and 800 m as the breakpoints. The area of abandoned land patches within the elevation range of each category and the proportion in the total study area were counted. The proportion of abandoned farmland to all farmland and the abandonment rates at different intervals are shown in Figure 14b.  
From the abandonment data extraction results and the kernel density analysis, it can be generally observed that the abandoned farmland in the study area is concentrated around residential areas. Thus, the distribution of abandoned farmland may be related to the distance from residential areas as well as the density of the road network.  
A line density analysis of the road network in the study area was carried out. The road network density was divided into five categories--extremely low, low, medium, high, and extremely high--according to the natural breaks. The area of abandoned farmland patches in each category and the proportion of abandoned farmland in the total farmland area was calculated, as shown in Figure 14c.  
Multi-ring buffers were established at an interval of 200 m from the vector boundary of the residential areas, and the cultivated areas were divided into areas 200 m, 200-400 m, 400-600 m, 600-800 m, and 800 m away from the residential areas. The area of abandoned land patches in different buffer zones and its proportion to the total area of abandoned  
Figure 14: Proportion of farmland to all farmland and abandonment rates at different ranges of different features. (**a**) Slope, (**b**) elevation, (**c**) road density, and (**d**) distance to residential area.  
land was calculated separately. The proportion of abandoned farmland to all farmland and the abandonment rates at different intervals are shown in Figure 14d.  
The area of total farmland, the area of farmland under cultivation, the area of abandoned farmland, and the abandonment rate of farmland in different ranges with different influencing factors, including elevation, slope, density of the road network, and distance from residential areas, are shown in Table 6.