# Soil Erosion Assessment and Prediction in Urban Landscapes: A New G2 Model Approach
## 3 Results
### G2 Model Results
The spatial distribution of factor R is shown in a raster form with a spatial resolution of 30 m. The average value of factor R is 731.19 MJ\(\cdot\)mm\(\cdot\)h\({}^{-1}\cdot\)ha\({}^{-1}\cdot\)y\({}^{-1}\), and a value range from 693.99 to 764,907 MJ\(\cdot\)mm\(\cdot\)h\({}^{-1}\cdot\)ha\({}^{-1}\cdot\)y\({}^{-1}\) recorded in the central part of the MPB for the first period (Figure 4a). By simulating the parameters according to climate scenario RCP 8.5 for the middle of the century and the available mean annual precipitation, rainfall erosivity was calculated for the second period (climate-based scenario). The values of rainfall erosivity in the study area also increased from 5% to 10%. The spatial distribution of rainfall erosivity has a range of values from 760.084 up to 841,398 MJ\(\cdot\)mm\(\cdot\)h\({}^{-1}\cdot\)ha\({}^{-1}\cdot\)y\({}^{-1}\), with an average value of 801.43 MJ\(\cdot\)mm\(\cdot\)h\({}^{-1}\cdot\)ha\({}^{-1}\cdot\)y\({}^{-1}\) (Figure 4b). Vegetation retention (Factor V) represents the result of remote detection in satellite images of different spatial and temporal resolutions, using a combination of spectral channels. In order to obtain data that is as relevant as possible, a set of 12 satellite images was used, one image for each month, in order to obtain average annual values. Satellite images from the vegetation and non-vegetation periods were used. For each month, one satellite image was selected which had the lowest percentage of cloudiness. Satellite images of Landsat Mission 5 and 7 were used for 2001, while satellite images of Landsat Mission 8 were used for 2019. Factor V values are dimensionless and can range from 1 to + \(\infty\). Based on the analysis of 2001, the value of coefficient V ranged from 1 to 3079.34 with an average  
Figure 4: Spatial distribution of factor R for 2001 (**a**) and for climate-based scenario (**b**). value of 32.83 (Figure 5a). The range of obtained values for 2019 is from 1 to 3547.43 with an average value of 39.76 (Figure 5b). The average value of factor S is 0.041 t-ha-h-ha-1 MJ-1 mm-1 which classifies these soils in the group of highly erodible soils [29]. The values of factor S range from 0.033 up to 0.07 t-ha-h-ha-1 MJ-1 mm-1 for the investigated area in which water bodies, lakes and urbanized areas were not taken into account (Figure 6a). The obtained values of coefficient S were used for both time periods. Terrain influence factor T was used for both time periods and is shown in Figure 6b. The range of terrain influence values ranges from 0.01 to 45.5 with an average value of 1.34. The landscape effect (L) has a range of values from 1 to 2 for both periods. The average value of factor L for 2001 for the entire study area is 1.22 (Figure 7a), while for 2019 the average value is 1.29 (Figure 7b). Figure 5: Spatial distribution of coefficient V for 2001 (**a**) and 2019 (**b**). Figure 6: Spatial distribution of soil erodibility coefficient S (**a**) and terrain influence factor T (**b**). The defined parameters (R, V, S, T, L) are the starting point for the calculation of soil loss according to the G2 model. Potential soil losses for both time periods are shown in the form of a raster databases with a spatial resolution of 30 m. The raster database represents the loss of soil for each pixel per unit t\(\cdot\)ha\({}^{-1}\cdot\)y\({}^{-1}\). Figure 8a shows the spatial distribution of soil loss for 2001. The average value in the investigated area is 4.11 t\(\cdot\)ha\({}^{-1}\cdot\)y\({}^{-1}\), and the value range is from 0 to 200.86 t\(\cdot\)ha\({}^{-1}\cdot\)y\({}^{-1}\). Soil loss assessment was done only in areas that are subject to intense erosion processes. Soil losses were estimated using the G2 model based on the current land cover from 2019, according to the adopted scenario RCP 8.5 for the period of the near future and the simulation of climate parameters.