PuSH - Publikationsserver des Helmholtz Zentrums München

Stoewer, M.* ; Knöller, K.* ; Stumpp, C.

Tracing freshwater nitrate sources in pre-alpine groundwater catchments using environmental tracers.

J. Hydrol. 524, 753-767 (2015)
DOI
Open Access Green möglich sobald Postprint bei der ZB eingereicht worden ist.
Groundwater is one of the main resources for drinking water. Its quality is still threatened by the widespread contaminant nitrate (NO3−). In order to manage groundwater resources in a sustainable manner, we need to find options of lowering nitrate input. Particularly, a comprehensive knowledge of nitrate sources is required in areas which are important current and future drinking water reservoirs such as pre-alpine aquifers covered with permanent grassland. The objective of the present study was to identify major sources of nitrate in groundwater with low mean nitrate concentrations (8 ± 2 mg/L). To achieve the objective, we used environmental tracer approaches in four pre-alpine groundwater catchments. The stable isotope composition and tritium content of water were used to study the hydrogeology and transit times. Furthermore, nitrate stable isotope methods were applied to trace nitrogen from its sources to groundwater. The results of the nitrate isotope analysis showed that groundwater nitrate was derived from nitrification of a variety of ammonium sources such as atmospheric deposition, mineral and organic fertilizers and soil organic matter. A direct influence of mineral fertilizer, atmospheric deposition and sewage was excluded. Since temporal variation in stable isotopes of nitrate were detected only in surface water and locally at one groundwater monitoring well, aquifers appeared to be well mixed and influenced by a continuous nitrate input mainly from soil derived nitrogen. Hydrogeological analysis supported that the investigated aquifers were less vulnerable to rapid impacts due to long average transit times, ranging from 5 to 21 years. Our study revealed the importance of combining environmental tracer approaches and a comprehensive sampling campaign (local sources of nitrate, soil water, river water, and groundwater) to identify the nitrate sources in groundwater and its vulnerability. In future, the achieved results will help develop targeted strategies for a sustainable groundwater management focusing more on soil nitrogen storage.
Altmetric
Weitere Metriken?
[➜Einloggen]
Zusatzinfos bearbeiten [➜Einloggen]
Publikationstyp Artikel: Journalartikel
Dokumenttyp Wissenschaftlicher Artikel
Korrespondenzautor
Schlagwörter Nitrogen; 15N; 18O; Source identification; Water transit times; Tritium; Isotopic Composition; Stable-isotopes; Source Identification; Shallow Groundwater; Agricultural Soils; Nitrogen; Oxygen; Aquifer; Fate; Contamination
ISSN (print) / ISBN 0022-1694
e-ISSN 1879-2707
Zeitschrift Journal of Hydrology
Quellenangaben Band: 524, Heft: , Seiten: 753-767 Artikelnummer: , Supplement: ,
Verlag Elsevier
Verlagsort Amsterdam
Nichtpatentliteratur Publikationen
Begutachtungsstatus Peer reviewed
Institut(e) Institute of Groundwater Ecology (IGOE)