Analysis of Pedological Factors and Uscs in the Contact Area of Đakovo Loess Plateau and Dilj Gora, Croatia

Abstract

The pedological factors concerning the Unified Soil Classification System (USCS) in the contact area of Đakovo loess plateau and Dilj gora have been explored. The study was carried out to create a crosscountry mobility map for vehicles. The spatial GIS analysis included soil units of Basic Soil Map (BSM) at a scale of 1:50000, which, according to the World Reference Base (WRB), contain within themselves the distribution of soil units, particle size distribution according to the United States Department of Agriculture (USDA) soil classification and organic content, as well as data from the Basic Geological Map (BGM) at a scale of 1:100000, together with the information on the original parent material from which the soils originate. Field sampling (72 samples) and laboratory sample analysis were performed according to the USCS. The samples were collected at the same locations (50 samples) as the profiles which had been extracted during the development of BSM to enable a comparison of the two classification systems. The analysis did not confirm a clear statistical connection between the USDA and USCS. The compatibility of BSM pedological units and low plasticity clays (CL) is clearly visible in all units, except for the units located on the alluvium. The presence of low plasticity clay (CL) and high plasticity clay (CH) has been confirmed in the stagnosols on the alluvium. By incorporating the geological basis into the spatial analysis, low plasticity clays were found to belong to the Quaternary source material, whereas high plasticity clays were formed on the parent substrate of Neogene age. Data analysis and cartographic representation of the results according to the Waterways Experiment Station (WES) Method of the cone index were obtained using fuzzy logic. The principles of fuzzy logic were used at the boundaries of pedological units due to the inability to define clear boundaries or the cessation of a particular type of soil's presence.

The USCS Mapping of Continental Croatia using Multinominal Logistic Regression and Inverse Distance Weighting Spatial Interpolation

“…The methods used in the classi cation of available data on soil pro les for the classi cation according to the ISSS method were described by Heštera (2020), where the grain size boundaries were de ned as shown in Fig. 3.…”

“…USCS samples covered 99.9% of the area of the BSM dominant soil type map unit (14), or 94.4% of the area when map units were divided into dominant and associated types (62). The coverage of the samples on geologic map units (24) was 95.6% of the total area.…”

“…Soil samples were collected and classi ed according to USCS to perform a spatial analysis and to establish correlations with ISSS pro les at the same sites in preparation of the Basic Pedological Map (BPM). The method for processing the pro le data and their classi cation is described in (Heštera 2020). Additional pro les were analysed according to USCS (414), 254 pro les were analysed by eld work and laboratory analyses in the period between September 2017 and October 2020, while 160 additional pro les were added to the existing ones by subsequent review of the literature (Fig.…”

“…4). Figure 4 presents only dominant BSM units (14), because the presentation of dominant and associated soil units (62) of BSM would be unreadable. Data on soil drainage conditions were taken from the BPM data (Fig.…”

The Effect of Clay on the Shear Strength of Microbially Cured Sand Particles

“…The physical characteristic parameters are shown in Table 2 , and the particle grading is shown in Figure 3 . According to USCS, the classification of clay and sand are CH and SP, respectively [ 23 , 24 ].…”