Soil textures

Abstract

The spatial distribution of soil types in the Upper Danube basin represents an important basic data set for the simulation of distributed soil water contents and soil temperatures. The hydraulic and thermal processes in soil models are infl uenced by the physical parameters of the model layers, which in turn are determined by the physical properties of the respective soil horizon. The Upper Danube basin is characterized by a wide variety of soil types comprising different textures. As a result of the signifi cant regional differences in bedrock, relief, climate, vegetation and the duration of soil genesis, the soil types found vary from the shallow raw soils of the high alpine regions to the fertile soils on loess deposits. The main soil textures found in the basin range from loamy clay to coarse sand and thus include almost every grain size. The distribution of soil types in the Upper Danube basin is presented in the 1:1,000,000 soil overview map (BÜK1000) of Germany. To reclassify the soils of the Upper Danube for DANUBIA, pedotransfer functions were used to calculate the hydraulic characteristics of the soil layers of each soil type. These in turn were used for a better representation and classifi cation of the individual soils into textural classes based on their hydraulic properties. As a result, the 32 soilscapes of the BÜK1000 found in the drainage basin were summarized into 15 textural classes aggregating hydrologically similar soils.