Infiltration capacity and hydraulic conductivity of 50 grassland soils with varying land-use intensity and biodiversity in southern Germany (Schwäbische Alb) in 2017

Up to now only little attention has been given to the role of biodiversity for soil erosion and flood generation. Both, soil erosion and flood generation are driven by the capability of soils to take up (infiltration) and conduct water to deeper soil layers (hydraulic conductivity). A high infiltration capacity (i.e., maximum infiltration rate under a given matrix potential) reduces the risk of surface runoff and thus soil erosion. A high hydraulic conductivity facilitates the storage of water in the deeper soil, which mediates the time until rainwater reaches groundwater or a stream and thus affects flood generation. The main objective of our study was to determine if biodiversity affects the infiltration capacity (vB) and the saturated (K*) and unsaturated (Ku) hydraulic conductivity near saturation of soils in established and agriculturally managed grassland systems.
For this, we measured vB with a hood infiltrometer at several matrix potentials on 50 grassland plots along a land-use intensity gradient in the Biodiversity Exploratory Schwäbische Alb, Germany, and calculated the saturated and unsaturated K. The studied plots were agriculturally managed grasslands with varying biodiversity and their size was 50 m x 50 m (i.e. the 50 grassland EPs of the Exploratory Schwäbische Alb). The measurements were done between 26 September and 20 October 2017.
The work has been funded by the DFG Priority Program 1374 ”Infrastructure-Biodiversity-Exploratories”and the Stiftung Landesbank Baden-Württemberg.