We were present at the EGU General Assembly 2016 in session SSS7.9/HS8.3.8 Challenges in soil physics research.
The title of our contribution is: Alterations of hydraulic soil properties influenced by land-use changes and agricultural management systems
Estimation and modeling of soil water movement and the hydrologic balance of soils requires sound knowledge about hydraulic soil properties (HSP). The Soil Water Characteristics, the Hydraulic Conductivity Function and the pore size distribution (PSD) are commonly used instruments for the mathematical representation of HSP. Recent research highlighted the temporal variability of these functions caused by meteorological or land-use influences. State of the art modeling software for the continuous simulation of soil water movement use a stationary approach for the HSP which means that their time dependent alterations and the subsequent effects on soil water balance cannot be simulated. Mathematical approaches to describe the evolution of PSD are nevertheless known, but there is a lack of sound data basis for parameter estimation. Based on extensive field and laboratory measurements at 5 locations in Eastern Austria and Germany, this study will quantify short-term changes in HSP, detect driving forces and introduce a method to predict the effects of soil and land management actions on the soil water balance.
Amongst several soil properties, field-saturated and unsaturated Hydraulic Conductivities will be determined using a hood infiltrometer in the field as well as by evaporation and dewpoint potentiometer method in the lab. All measurements will be carried out multiple times over a span of 3 years which will allow for detailed monitoring of changes in HSP. In land-use forms, where we expect significant inter-seasonal changes, the sites will be equipped with sensors and data loggers for soil moisture, soil temperature and matric potential. The choice of experimental field sites follows the intention to involve especially the effects of tillage operations, different cultivation strategies, microclimatically effective structures and land-use changes. The international project cooperation enables the coverage of a broad range of soil types as well as climate conditions and hence will have broad applicability of the implemented model modifications.