Spatial analysis of soil quality through landscape patterns in the Shoor River Basin, Southwestern Iran

The soil quality is the inherent capacity of soils to function in an ecosystem, which depend on soil properties and change under the influence of landscape patterns. This study aimed to evaluate the soil quality in the Shoor River basin, southwestern Iran, by using the soil quality indicators based on two approaches, i.e., minimum data set and total data set. The spatial relationships of the soil quality to landscape pattern properties (e.g., density, dominance, shape, aggregation, and diversity of patches) were also analyzed through the exploratory regression in the Arc GIS 10.5 software in addition to the effects of land use, elevation, slope, and normalized difference vegetation index (NDVI) on the soil quality. The results indicated that the soils of northern and eastern regions of the study area had higher levels of quality than those of southern and western regions. Very low and very high of soil quality covered<15% (43413 ha) and 20% (56759 ha) of the basin, respectively. The hot spots of soil quality were observed in the eastern and northern regions of the study area whereas the cold spots of soil quality were seen in the southern and western regions. According to the findings, the soil quality level was higher in the forest land use compared to farmland and rangeland. The results confirmed that the soil quality had significant spatial relationships with elevation, slope, and NDVI (0.12 < r < 0.35, p-value < 0.1). Moreover, the soil quality had significant positive spatial relationships with aggregation and dominance of patches (0.40 < r < 0.62, p-value < 0.05), whereas it had significant negative spatial relationships with the density and diversity of patches (0.35 < r < 0.63, p-value < 0.1). However, there were no significant relationships between the soil quality and the shapes of patches. This study confirmed that the soil quality would vary in different landscape patterns and that it might change as a result of development and anthropogenic activities.

Automated summary

This study evaluates the soil quality in the Shoor River basin in southwestern Iran using two approaches, and analyzes its relationships with landscape pattern properties and various factors. The results show variations in soil quality across different regions, with significant correlations with elevation, slope, and vegetation index.