Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1016/j.advwatres.2016.07.003
Title (Primary) Groundwater head controls nitrate export from an agricultural lowland catchment
Author Musolff, A.; Schmidt, C.; Rode, M.; Lischeid, G.; Weise, S.M.; Fleckenstein, J.H.
Source Titel Advances in Water Resources
Year 2016
Department ASAM; HDG; CATHYD
Volume 96
Page From 95
Page To 107
Language englisch
Keywords Water quality; Nitrate; Lowland catchment; Export regime; Concentration-discharge relationship
UFZ wide themes RU2;
Abstract Solute concentration variability is of fundamental importance for the chemical and ecological state of streams. It is often closely related to discharge variability and can be characterized in terms of a solute export regime. Previous studies, especially in lowland catchments, report that nitrate is often exported with an accretion pattern of increasing concentrations with increasing discharge. Several modeling approaches exist to predict the export regime of solutes from the spatial relationship of discharge generating zones with solute availability in the catchment. For a small agriculturally managed lowland catchment in central Germany, we show that this relationship is controlled by the depth to groundwater table and its temporal dynamics. Principal component analysis of groundwater level time series from wells distributed throughout the catchment allowed derivation of a representative groundwater level time series that explained most of the discharge variability. Groundwater sampling revealed consistently decreasing nitrate concentrations with an increasing thickness of the unsaturated zone. The relationships of depth to groundwater table to discharge and to nitrate concentration were parameterized and integrated to successfully model catchment discharge and nitrate export on the basis of groundwater level variations alone. This study shows that intensive and uniform agricultural land use likely results in a clear and consistent concentration-depth relationship of nitrate, which can be utilized in simple approaches to predict stream nitrate export dynamics at the catchment scale.
Persistent UFZ Identifier
Musolff, A., Schmidt, C., Rode, M., Lischeid, G., Weise, S.M., Fleckenstein, J.H. (2016):
Groundwater head controls nitrate export from an agricultural lowland catchment
Adv. Water Resour. 96 , 95 - 107 10.1016/j.advwatres.2016.07.003