Vulnerability of soil aggregates in relation to soil properties

Abstract

Stability of soil structure represents an indicator of soil quality. The aim of this paper was to assess the effect of soil properties on structure vulnerability in an Orthic Luvisol. The aggregates were most vulnerable to fast wetting (mean Kv1 = 9.99, i.e. this effect can decrease the aggregate size 9.99 times). Lower destruction was caused by slow wetting and drying (Kv2 = 3.70) and mechanical forces (Kv3 = 1.67). Fine silt (particles of 0.002-0.01 mm) was the most important soil characteristic decreasing aggregate vulnerability (r = -0.334, -0.248, and -0.393 for Kv1, Kv2, and Kv3, respectively). Silt (0.01-0.05 mm) increased vulnerability to fast wetting (r = 0.318). Very fine sand (0.05-0.1 mm) increased vulnerability to mechanical impacts (r = 0.307). Organic carbon decreased vulnerability only slightly. Humus quality was rather related to porosity. Higher moisture of samples in time of collection increased aggregate vulnerability. Multiple regression, used for description of the effect of basic soil properties, provided the best model for Kv1 (R2 = 27.45%), the poorest for Kv2 (R2 = 7.23%).

Keywords

• soil structure
• aggregate vulnerability
• porosity
• soil moisture
• soil texture
• organic matter