A revisit of the sandblasting technique to measure soil crust strength

Authors: DEVIREN SAYGIN, SELEN - University Of Ankara; Huang, Chi Hua

Submitted to: Catena
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/22/2022
Publication Date: 2/1/2022
Citation: Deviren Saygin, S., Huang, C. 2022. A revisit of the sandblasting technique to measure soil crust strength. Catena. 212:106073. https://doi.org/10.1016/j.catena.2022.106073.
DOI: https://doi.org/10.1016/j.catena.2022.106073

Interpretive Summary: Wind erosion is causing land degradation and air quality problems in many parts of the world. However, methods to assess a soils vulnerability under erosive wind conditions rely on the use of wind tunnels which are expensive and require laborious procedures to make the measurements. In this research, a commonly available sandblasting device was adopted to simulate abrading on a crusted soil surface. The sand abrading time can be adjusted between 2 to 60 seconds and the amount of soil detachment can be obtained immediately. Results from the two silt loam soils tested showed that one soil has a lower crust strength, but with a greater organic carbon content, as compared to the other soil despite these two soils have very similar physical properties. This simple procedure is very sensitive to soil management practices that may lead to different surface crust strengths that may not be detected by other measurements.

Technical Abstract: Wind erosion is one of the dominant degradation processes in arid, semi-arid, and semi-humid regions of the world that are vulnerable to erosion and land degradation. However, crust development significantly affects the amount of sediment carried by the wind. In this context, the availability of a simple procedure to measure the strength of soil crust provides the benefits of assessing the soil's vulnerability for wind erosion and effective implementation of control practices to minimize the risk of wind erosion for these fragile ecosystems. This study aims to test a practical tool and approach designed in the National Soil Erosion Research Laboratory (USA) that directly measures the susceptibility of the soil crust to wind erosion processes. The technique uses a conventional sandblasting tool that impacts sand particles on a soil crust for different times, ranging from 2 to 60 seconds, resulting in blasting sand mass (q, g) ranging from 0.44 to 3.55 g during the test. The soils used for experiments were two silt loams, Palouse and Nansene, sampled from US Pacific Northwest. To obtain soil crust, the sieved soils were exposed to rainfall simulations for 30 min at 10 mm/h and then air-dried. Results showed that an increase in q generally caused a significant increase in soil loss through abrasion (AR, g) for both soils (P<0.05*). For the same amount of blasting sand, higher AR values were recorded for that Palouse soil which has higher soil organic carbon content as compared to the Nansene soil. In addition, differences observed in terms of crust strength were also examined by considering the aggregate size distributions, the organic carbon content of aggregates, and macro-micro-aggregate distributions. These findings showed that the technique is very sensitive to cropping and management history despite the bulk soil properties of these two soils are very similar. This simple procedure is useful to assess soil crust strength against impacting particles without the need to use a wind tunnel and the associated laborious testing procedures.