Short Communication Lysimeter Soil Retriever (LSR)—a new technique for retrieving soil from lysimeters for analysis Sascha Reth 1 *, Manfred Seyfarth 2 , Oliver Gefke 1 , and Hartmut Friedrich 2 1 Institute of Soil Ecology, GSF – National Research Center for Environment and Health, Department of Environmental Engineering, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany 2 UGT Environmental Measurement Devices Ltd., Eberswalder Str. 58, 15374 Müncheberg, Germany Accepted December 12, 2006 Key words: in situ / undisturbed sampling / soil structure / lysimeter vessel / soil processes / soil monolith  2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 1436-8730/07/0306-345 J. Plant Nutr. Soil Sci. 2007, 170, 345–346 DOI: 10.1002/jpln.200625069 345 1 Introduction In Europe, about 2,500 lysimeters are installed. They were originally built for investigations of the hydrological cycle, pesticide degradation, and nutrient fluxes (e.g., Winton and Weber , 1996). Present research areas of lysimeter studies include biological processes, such as root development of plants and enzyme activities (e.g., Dizer et al., 2002; Schloter et al., 2005), which are often closely related to soil structure. At present, data on soil structure can be estimated by trans- ferring the information of the surrounding soil to the lysimeter at the beginning of an experiment. After long-term experimenta- tion, there was a lack of knowledge on the transformations and evolution of the lysimeter soil. Former methods (e.g., Keese and Knappe, 1996; Godlinski et al., 2004), which removed the soil manually from the lysimeter vessel or which forced the soil out of the casing by applying large pressure, were dissatisfying because the soil structure was largely disturbed. A new technique, the Lysimeter Soil Retriever tool (LSR) (Reth et al., 2006), was developed to retrieve the soil out of lysimeter vessels with minimal disturbance of soil structure. This techni- que also makes the sampling of lysimeter soil more time-effi- cient and reproducible. The method can be applied to a range of lysimeter sizes from 0.5 to 2 m 2 and up to 2 m deep. 2 Materials and methods The soil-filled lysimeter vessel is placed vertically in the LSR on a platform with a roll-riding system and fixed with a collar (Fig. 1). The monolith is cut free at the rim in order to avoid compres- sing of the soil, when axial pressure is applied to overcome the fraction force between monolith and the vessel wall (see Fig. 2 A). For this purpose, a wire-saw is threaded through a borehole drilled along the edge of the monolith from top to the * Correspondence: Dr. S. Reth; e-mail: sascha.reth@gsf.de 2 m Figure 1: Schematic view of the Lysimter Soil Retriever (LSR) with a lysimeter (1, cut off plate; 2, lysimeter vessel; 3, collar; 4, wire saw; 5, roll-riding system; 6, supporting frame; 7, telescopic hydraulic ram). A B Figure 2: A) View on the LSR: lysimeter vessel, inserted in the supporting frame and fixed by the collar; B) view on the cut-off plate, wire saw, and support ring surrounding the soil slice.