 |
| Titel |
Effects of antecedent soil moisture on runoff modeling in small semiarid watersheds of southeastern Arizona |
| VerfasserIn |
Y. Zhang, H. Wei, M. A. Nearing |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1027-5606
|
| Digitales Dokument |
URL |
| Erschienen |
In: Hydrology and Earth System Sciences ; 15, no. 10 ; Nr. 15, no. 10 (2011-10-18), S.3171-3179 |
| Datensatznummer |
250012994
|
| Publikation (Nr.) |
 copernicus.org/hess-15-3171-2011.pdf |
|
|
|
|
|
| Zusammenfassung |
| This study presents unique data on the effects of antecedent soil moisture
on runoff generation in a semi-arid environment, with implications for
process-based modeling of runoff. The data were collected from four small
watersheds measured continuously from 2002 through 2010 in an environment
where evapo-transpiration approaches 100% of the infiltrated water on the
hillslopes. Storm events were generally intense and of short duration, and
antecedent volumetric moisture conditions were dry, with an average in the
upper 5 cm soil layer over the nine year period of 8% and a standard
deviation of 3%. Sensitivity analysis of the model showed an average of
0.05 mm change in runoff for each 1% change in soil moisture, indicating
an approximate 0.15 mm average variation in runoff accounted for by the
3% standard deviation of measured antecedent soil moisture. This compared
to a standard deviation of 4.7 mm in the runoff depths for the measured
events. Thus the low variability of soil moisture in this environment
accounts for a relative lack of importance of storm antecedent soil moisture
for modeling the runoff. Runoff characteristics simulated with a nine year
average of antecedent soil moisture were statistically identical to those
simulated with measured antecedent soil moisture, indicating that long term
average antecedent soil moisture could be used as a substitute for measured
antecedent soil moisture for runoff modeling of these watersheds. We also
found no significant correlations between measured runoff ratio and
antecedent soil moisture in any of the four watersheds. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|