## 3 Results  
### Land-Use Change and Spatial Characteristics  
#### 3.1.1 Land-Use Change Analysis  
The land-use change in Shaanxi Province from 1990 to 2020 is shown in Table 2 and Figure 2. The main land-use types in Shaanxi Province during the study period were grassland, accounting for about 37% of the total study area; farmland, accounting for about 35%; and forestland, accounting for about 22%. Water areas, built-up land, and barren land accounted for the smallest percentages, and the total proportion of these 3 types was about 5%. Based on the land-use change and the proportion of various land-types, farmland was in a dynamic increase process prior to the implementation of the project, and it has been in a reduction process since implementation. The ratio of cultivated land to the total area decreased from 35% in 1990 to 32% in 2020. Forestland was in a dynamic increase process prior to the implementation of the project, with a slight growth rate. Since the implementation of the project, it has been in a state of growth; the change was large, with the proportion increasing from 22% in 1990 to 25% in 2020. The size of the grassland area was directly affected by the project implementation, and the overall change was small, but it is in a state of fluctuation. The project implementation had little influence on the water areas, and the overall change was small, with the total proportion being maintained at 1%. The most noticeable dynamic shift in built-up land was due to the acceleration of urbanization, which resulted in a massive increase in built-up land from 1% in 1990 to 3% in 2020. With the implementation of the project and urbanization, more and more land has \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multicolumn{2}{c}{**Ecosystem Services**} & **Farmland** & **Forestland** & **Grassland** & **Water Areas** & **Built-Up Land** & **Barren Land** \\ \hline \multirow{3}{*}{Provisioning services} & Food production & 179.86 & 41.10 & 37.98 & 130.21 & 45.57 & 0.81 \\  & Raw materials & 39.88 & 94.40 & 55.88 & 37.44 & 48.83 & 2.44 \\  & Water supply & \(-\)212.41 & 48.83 & 30.93 & 1349.34 & \(-\)603.87 & 1.63 \\ \hline \multirow{4}{*}{Regulating services} & Gas regulation & 144.86 & 310.48 & 196.41 & 125.33 & 0 & 10.58 \\  & Climate regulation & 75.69 & 928.99 & 519.23 & 372.74 & 0 & 8.14 \\  & Environment & 21.97 & 272.23 & 171.45 & 903.36 & \(-\)400.41 & 33.37 \\  & purification & \multirow{2}{*}{243.34} & \multirow{2}{*}{607.93} & \multirow{2}{*}{380.33} & \multirow{2}{*}{16,641.30} & \multirow{2}{*}{\(-\)870.80} & \multirow{2}{*}{19.53} \\  & Hydrological & & & & & & \\  & regulation & & & & & & \\ \hline \multirow{4}{*}{Support services} & Soil conservation & 86.64 & 378.03 & 239.27 & 151.37 & 3.26 & 12.21 \\  & Nutrient cycle & 25.23 & 28.89 & 18.45 & 11.39 & 0 & 0.81 \\  & maintenance & Biodiversity & 27.67 & 344.25 & 217.57 & 415.06 & 55.34 & 11.39 \\  & maintenance & & & & & & \\ \hline \multirow{4}{*}{Cultural services} & Aesthetic landscape & 12.21 & 150.97 & 96.03 & 307.63 & 195.32 & 4.88 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Value coefficients of land ecosystem services in Shaanxi Province (USD ha\({}^{-1}\)). undergone development and utilization, resulting in a gradual reduction in barren-land areas during the study period. From the perspective of spatial change, farmland is mainly concentrated in the central region (Figure 3). With the implementation of the project and urbanization, farmland showed a decreasing trend. Forestland showed an increasing trend, concentrated in southern Shaanxi and the central mountainous areas. Grassland is in a dynamic process, mainly distributed in northern Shaanxi. Water areas are relatively modest, with little change, and are primarily spread along rivers. Barren land is primarily dispersed in northern Shaanxi's sandy area and has been steadily shrinking since the project was implemented. The most visible trend is the increase in built-up land centered in central Shaanxi Province and the cities' core regions.