Spatial variability of soil aggregate stability at the scale of an agricultural region in Tunisia

摘要: Abstract Soil aggregate stability is a key factor in soil resistance to water erosion, which threat soils large part of northern Tunisia. The analysis the spatial variability provides both agronomic and environmentally useful information. However, extensive measurements remain tedious expensive. This study explores two different approaches as alternative stability. One approach estimated via laboratory elementary properties using multiple linear regressions known pedotransfer functions. second approach, methodologically innovating, was based on geological pattern proxy for regression-kriging analysis. A set 113 samples from an 800 km 2 agricultural region that included Lebna watershed (Cap Bon, Tunisia) were collected surface layer (0–10 cm depth). Samples analyzed (i.e., texture, total carbon nitrogen, iron, CaCO 3 , salinity, CEC pH) according normalized method (ISO/DIS 10930, 2012), considers three indexes (MWD) calculated contrasted wetting conditions disruptive energies. Most area non-salted with alkaline pH relatively low organic content. Of soils, 35% clay 55% had balanced texture. average (MWD mean ) ranged 0.38 2.80 mm, this property showed instable very stable ones. Analysis functions determined best predictor variables silt, matter iron. Geostatistical analyses at regional scale spatially structured (variograms sills reaching 5 km distance). Using information ancillary data, prediction similar regression-kriged map associated uncertainties developed. resulting maps methods can be development management options minimize erosion risks studied area.