Details zur Publikation

Kategorie Textpublikation
Referenztyp Zeitschriften
DOI 10.5194/bg-14-4391-2017
Titel (primär) Carbon and nutrient export regimes from headwater catchments to downstream reaches
Autor Dupas, R.; Musolff, A.; Jawitz, J.W.; Rao, P.S.C.; Jäger, C.G.; Fleckenstein, J.H.; Rode, M.; Borchardt, D.
Quelle Biogeosciences
Erscheinungsjahr 2017
Department ASAM; HDG
Band/Volume 14
Heft 18
Seite von 4391
Seite bis 4407
Sprache englisch
UFZ Querschnittsthemen RU2;
Abstract Excessive amounts of nutrients and dissolved organic matter in freshwater bodies affect aquatic ecosystems. In this study, the spatial and temporal variability in nitrate (NO3), dissolved organic carbon (DOC) and soluble reactive phosphorus (SRP) was analyzed in the Selke (Germany) river continuum from three headwaters draining 1–3 km2 catchments to two downstream reaches representing spatially integrated signals from 184–456 km2 catchments. Three headwater catchments were selected as archetypes of the main landscape units (land use  ×  lithology) present in the Selke catchment. Export regimes in headwater catchments were interpreted in terms of NO3, DOC and SRP land-to-stream transfer processes. Headwater signals were subtracted from downstream signals, with the differences interpreted in terms of in-stream processes and contributions from point sources. The seasonal dynamics for NO3 were opposite those of DOC and SRP in all three headwater catchments, and spatial differences also showed NO3 contrasting with DOC and SRP. These dynamics were interpreted as the result of the interplay of hydrological and biogeochemical processes, for which riparian zones were hypothesized to play a determining role. In the two downstream reaches, NO3 was transported almost conservatively, whereas DOC was consumed and produced in the upper and lower river sections, respectively. The natural export regime of SRP in the three headwater catchments mimicked a point-source signal (high SRP during summer low flow), which may lead to overestimation of domestic contributions in the downstream reaches. Monitoring the river continuum from headwaters to downstream reaches proved effective to jointly investigate land-to-stream and in-stream transport, and transformation processes.
dauerhafte UFZ-Verlinkung
Dupas, R., Musolff, A., Jawitz, J.W., Rao, P.S.C., Jäger, C.G., Fleckenstein, J.H., Rode, M., Borchardt, D. (2017):
Carbon and nutrient export regimes from headwater catchments to downstream reaches
Biogeosciences 14 (18), 4391 - 4407 10.5194/bg-14-4391-2017