Method for the compilation of a stratified and harmonized soil physical database using legacy and up-to-date data sources

Abstract

An attempt is outlined for the compilation of an integrated and harmonized stratified soil physical database serving hydrologic modeling, as the basis of estimating soil hydraulic parameters in the unsaturated zone. Due to the appropriate spatial and thematic resolution and data processing status, the Digital Kreybig Soil Information System (DKSIS) and Hungarian Agrogeological Database (HAD) were chosen as pedological and agrogeological data sources for describing the soil physical properties in the unsaturated zone. The DKSIS contains legacy soil data (as hy, pH, salt, OM, CaCO3content, etc.) in finely stratified resolution (3–5 soil layers within 1.5–2.0 m), but lacks particle size data. HAD has a coarser stratification (8–15 layers within 8–10 m) with detailed particle size data. The five-cleft FAO texture classification can serve as an interface in their joint application. The particle size and hy data pairs from the existing Hungarian Soil Monitoring (TIM) network made it possible to define the relation between FAO texture class vs.hyvalue, and based on the HYPRES database each FAO texture class can be characterized by typical Mualem-van Genuchten parameter sets (Wöstenet al., 1999). The compiled, harmonized database characterizes the distinguished soil and sediment layers – with a thickness of at least 10 cm – for a 690 km2large model area, describing their thickness and texture classes to the depth of the permanent groundwater level, in every single square kilometer cell of the model area. The compiled database is indispensable in the model simulation based analysis of regional water management problems like drought, flood and inland inundation.