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Disturbance of lacustrine and alluvial soils could increase aeolian dust emissions in the eastern Great Basin, but little is known about the susceptibility of these land surfaces to wind erosion. Threshold friction velocity ( u ∗ t ), a necessary parameter to estimate wind erosion potential, is difficult to accurately measure; methods to estimate u ∗ t from alternate measurements would be useful. We measured u ∗ t and sediment production rate with a portable wind tunnel, and quantified relationships between u ∗ t and eleven easier-to-measure soil surface properties for both undisturbed and disturbed lacustrine and alluvial soils in Snake Valley, Utah. Soil surface type and disturbance significantly influenced u ∗ t , sediment production rate, and the relationships between u ∗ t and easier-to-measure soil surface properties. Only soils with surficial rock fragments and weak physical crusts reached u ∗ t before disturbance, whereas all surface types reached u ∗ t following disturbance. Soils with weak physical crusts had the lowest average u ∗ t and highest average sediment production rate before and after disturbance. Surprisingly, however, disturbance reduced sediment production rate. Soils with weak physical crusts and surficial rock cover are likely the most susceptible to wind erosion and subsequent dust generation both before and after disturbance. Silt concentration and penetrometer resistance were significant predictors of u ∗ t in undisturbed soils with weak physical crusts and surficial rock cover. Following disturbance, clay concentration and aggregate stability were significant predictors for soils with hard salt crusts and surficial rock cover. Prediction of u ∗ t using alternate measurements is promising, but u ∗ t measurement uncertainty must be considered. [ABSTRACT FROM AUTHOR]

Highlights: [•] Biocrust functions impact soil surface properties, pedogenesis and hydrology. [•] Biocrust affected granulometry by increasing the clay and fine-silt fractions. [•] The infiltration controlled by the biocrust was inversed to the rainfall gradient. [Copyright &y& Elsevier]

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The article presents a study on the multi-decadal effects of soil grazing in biogeochemical and physical properties in Southeast Utah. It highlights the comparison of non-grazed grasslands in Canyonlands National Park along with their geomorphic, geochemical and geologic features. It also outlines the issue of soil erosion as well as impact of carbon and nitrogen on the land.

The Free State has been identified as the region with the most dust sources in South Africa. These dust sources can be linked with the large, heavily cultivated cropland areas in this province, which leaves fields vulnerable to wind erosion after the harvest in the winter. For this study, the focus was on the factors that influence the emission from bare, flat surfaces on agricultural lands in this region. The Portable In-Situ Wind Erosion Laboratory (PI-SWERL) was used to measure the emission flux from adjacent crusted and loose surfaces, which was combined with shear strength, moisture, and soil texture measurements. Boosted regression tree (BRT) analyses were used to identify the variable with the highest relevance on the emission flux. On the whole dataset, that the shear strength is the most important variable that controls the emission. This is reflected in the significantly lower emission from the crusted surfaces (0.49 mg m−2 s−1) compared to that of loose surfaces (2.34 mg m−2 s−1). However, for crusted surfaces, the presence of abraders appeared to be the most significant factor in emission, showing a power relationship between the abrader count and the emission flux (R2 = 0.76). In the case of the loose surfaces, the presence of clay and silt was a major influence in emissivity, with a linear relationship between the two variables (R2 = 0.68). This difference in factors depending on the agricultural disturbance, asks for a more holistic approach when predicting emission from such arid cropland areas. [ABSTRACT FROM AUTHOR]