TY  - JOUR
A1  - Klaus, Julian
A1  - Zehe, Erwin
A1  - Elsner, Martin
A1  - Palm, Juliane
A1  - Schneider, Dorothee
A1  - Schroeder, Boris
A1  - Steinbeiss, Sibylle
A1  - van Schaik, Loes
A1  - West, Stephanie
T1  - Controls of event-based pesticide leaching in natural soils: A systematic study based on replicated field scale irrigation experiments
T2  - Journal of hydrology
N2  - Tile drains strongly influence the water cycle in agricultural catchment in terms of water quantity and quality. The connectivity of preferential flow to tile drains can create shortcuts for rapid transport of solutes into surface waters. The leaching of pesticides can be linked to a set of main factors including, rainfall characteristics, soil moisture, chemical properties of the pesticides, soil properties, and preferential flow paths. The connectivity of the macropore system to the tile drain is crucial for pesticide leaching. Concurring influences of the main factors, threshold responses and the role of flow paths are still poorly understood. The objective of this study is to investigate these influences by a replica series of three irrigation experiments on a tile drain field site using natural and artificial tracers together with applied pesticides. We found a clear threshold behavior in the initialization of pesticide transport that was different between the replica experiments. Pre-event soil water contributed significantly to the tile drain flow, and creates a flow path for stored pesticides from the soil matrix to the tile drain. This threshold is controlled by antecedent soil moisture and precipitation characteristics, and the interaction between the soil matrix and preferential flow system. Fast transport of pesticides without retardation and the remobilization could be attributed to this threshold and the interaction between the soil matrix and the preferential flow system. Thus, understanding of the detailed preferential flow processes clearly enhances the understanding of pesticide leaching on event and long term scale, and can further improve risk assessment and modeling approaches. (C) 2014 Elsevier B.V. All rights reserved.
KW  - Irrigation experiment
KW  - Preferential flow
KW  - Threshold
KW  - Pesticide transport
Y1  - 2014
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/37852
SN  - 0022-1694
SN  - 1879-2707
VL  - 512
SP  - 528
EP  - 539
PB  - Elsevier
CY  - Amsterdam
ER  -