Effect of landscape fragmentation on soil quality and ecosystem services in land use and landform types

This study was carried out to model the ecosystem services, i.e., habitat quality, carbon storage, nutrient export, and soil export using the InVEST software and soil quality through the integrated quality index across Shoor River basin, southwestern Iran, as well as their relationships to landscape metrics using the Pearson's correlation and ordered least square regression. The interactions between ecosystem services efficiency, soil quality and landscape fragmentation were also evaluated using the ternary analysis. The results showed that the northern and eastern parts of the study area had more suitability to provide soil quality, habitat quality, carbon storage, and ecosystem service efficiency than the southern and western parts while this trend was the opposite for soil and nutrient exports. The highest soil quality, habitat quality, carbon storage, and ecosystem services efficiency were calculated for the forest's land use and the ridge/tops landform. The highest nutrient and soil exports were also seen in agriculture and rangeland land uses, respectively, as well as for plain and ridge/top landforms, respectively. Statistical analysis confirmed that there were positive and moderate relationships between soil quality to habitat quality and carbon storage and no certain relationships to soil and nutrient export. Moreover, patch density had a negative impact on habitat quality, carbon storage, soil quality, and ecosystem services efficiency and a positive effect on soil and nutrient exports. This trend was the opposite for the largest patch index, patch cohesion index, and effective mesh size. The findings demonstrated that increasing the landscape fragmentation decreased soil quality, habitat quality, carbon storage, and ecosystem services efficiency but increased nutrient and soil exports. Furthermore, the interactions between ecosystem services efficiency, soil quality, and landscape fragmentation were changed under the influence of the dominant land use and landform types across the sub-basins of the study area.