New Methods in Soil Science Studies in Paired Watersheds with an Approach to Updating Service Description in Paired Watersheds of Dehgin, Hormozgan Province

Abstract

One of the most critical environmental problems globally is soil erosion, which leads to several problems in the field of economy and sustainable development. This study aims to use new methods in soil science studies of the paired sub-catchments to update service descriptions in Dehgin, Hormozgan Province. For this purpose, to select sampling sites of pedons and soil samples, the conditional Latin Hypercube sampling (cLHS) method was used using environmental covariates (digital elevation model), which derivate from unmanned aerial vehicles (UAV), phantom4 pro, and multirotor. The results showed two main land types in the study area, including hills, plateaus, and high terraces. Soil development in the region is mainly influenced by elevation, and the soils of the hill lands are directly related to the type of parent material and slope percentage. In the areas containing wooded pasture and areas with silt loam texture class, the aggregate stability values are higher, which are auxiliary covariates essential and influential parameters in the aggregate stability map. The RMSE and R2 values are 0.32 and 0.26, respectively, for the evaluation map criteria. The values of cation exchange capacity (CEC) and nitrogen in both control and sample sub-catchments are small and the maximum amounts of soil organic carbon in the sample sub-catchment are higher than in the control sub-catchment. The use of new methods including UAV, accurate sampling methods using high-resolution environmental covariates, and digital soil mapping can reduce the number of soil samples, increase the accuracy of output maps, and provide more accurate erosion estimation results, which has reduced time and cost compared to the old methods.

Keywords

• latin hypercube sampling
• pedons
• photogrametry
• soil erosion
• unmanned aerial vehicles