|
Titel |
Variability of DOC and nitrate responses to storms in a small Mediterranean forested catchment |
VerfasserIn |
Susana Bernal, Andrea Butturini, Francesc Sabater |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1027-5606
|
Digitales Dokument |
URL |
Erschienen |
In: Hydrology and Earth System Sciences ; 6, no. 6 ; Nr. 6, no. 6, S.1031-1041 |
Datensatznummer |
250003860
|
Publikation (Nr.) |
copernicus.org/hess-6-1031-2002.pdf |
|
|
|
Zusammenfassung |
Severe drought periods
followed by intense rainfall often leads to major floods in Mediterranean
catchments. The resulting hydrology is complex and the
response of solutes in the streams is often unpredictable. This study aimed to
identify the most relevant factors controlling the
hydrological responses to storms of an intermittent Mediterranean stream and to
link those factors with dissolved organic carbon (DOC) and
nitrate during storm events. Measurements of climate, hydrology, DOC and nitrate
concentrations during 26 storm events over three hydrological
years were analysed. The contribution of the storm events to the total DOC and
nitrate annual export was also calculated. Nitrate was
mainly mobilised during high flow, while most of the DOC export occurred during
baseflow. Solute concentrations peaked after drought
periods and the solute export was maximal during the largest rainfalls (i.e.
> 100 L m-2). One single large storm contributed some 22% of
the total annual export of DOC, and about 80% of that of nitrate. Discharge was
a good predictor of neither DOC nor nitrate responses, so variables
other than discharge were considered. Factor Analysis was used to identify the
main factors controlling the biogeochemical responses. Antecedent
moisture conditions and the magnitude of the storm event were the most relevant
factors and accounted for 63% of the total variance.
Solute responses during high flow were highly variable. However, solute
concentration changes showed a significant and moderate relationship
with the factors controlling the hydrological responses (i.e. Δ DOC v.
the antecedent moisture conditions and Δ NO3-N v.
the magnitude of the storm event).
Keywords: dissolved organic carbon, nitrate, Mediterranean, drought,
Fuirosos catchment, storms |
|
|
Teil von |
|
|
|
|
|
|