When analyzing the texture of the sinkhole soil, we encountered a discrepancy between the sedimentation-pipette method and the laser particle size analyzer. Different results depending on the method used, cause problems in further interpretation of the results, such as the role of aeolian transport, deposition of material at the bottom of sinkholes, and pedogenesis. In addition, the boundaries between the sandy and silty fraction are set at 0.063 mm in sedimentology and at 0.05 mm in pedology. The two disciplines use different texture triangles and denominations. In two sinkholes in the Divača Karst, DLN 1 and DLN 3, we determined the soil texture with the sedimentation-pipette method and with a laser particle size analyzer on 17 samples. For both sinkholes, the t-test showed statistically typical differences in the amount of all fractions. The sedimentation-pipetting method showed 2.4 times more clay and 4 times more sand than the laser analyzer that yielded 1.7 times more silt. Analysis of variance showed that there is a statistically significant difference depending on the method used regarding the results of the fraction of clay, total silt and coarse silt. However, there are no statistically significant differences between the sinkholes. There are also statistically significant differences in the fraction of coarse and fine silt between the sinkholes. The differences might be the result of the flaking of clay particles due to the laser analyzer, the non-spherical shape of the particles and the content of organic matter, which absorbs some light when measured with a laser analyzer and consequently gives inaccurate results.
Analysis of variance confirmed that the sinkholes differ from each other in the content of coarse and fine silt. The variability of texture depending on the depth is showing different trends depending on the method used.
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