Potential erodibility of semi‐arid steppe soils derived from aggregate stability tests

Erosion is a severe threat to the sustainable use of agricultural soils. However, structural resistance soil against disruptive forces steppe soils experience under field conditions has not been investigated. Therefore, 132 topsoils grass- and cropland covering large range physico-chemical properties (sand: 2–76%, silt: 18–80%, clay: 6–30%, organic carbon: 7.3–64.2 g kg−1, inorganic 0.0–8.5 pH: 4.8–9.5, electrical conductivity: 32–946 μS cm−1) from northern Kazakhstan were assessed for their potential erodibility using several tests. An adjusted drop-shatter method (low energy input 60 Joule on 250-cm3 block) was used estimate stability dry weak mechanical forces, such as saltating particles striking surface causing wind erosion. Three wetting treatments with various energies (fast wetting, slow wet shaking) applied simulate different effects water. Results indicate that aggregate higher grassland than declined decreasing carbon content. The results test suggested 29% at risk erosion, but only 6% high (i.e. erodible fraction >60%). In contrast, fast treatment revealed 54% samples prone become “very unstable” 44% “unstable” during heavy rain or snowmelt events. Even comparable light events raindrop impact, 53–59% “unstable.” Overall, semi-arid seem much more susceptible water Considering future projections increasing precipitation in Kazakhstan, we conclude erosion potentially underestimated needs be taken into account when developing land strategies. Highlights Organic matter important binding agent enhancing aggregation topsoils. Tillage always declines even without changes. All croplands are independent properties. Despite conditions, by seems wind.