|
Titel |
The hydrological regime of a forested tropical Andean catchment |
VerfasserIn |
K. E. Clark, M. A. Torres, A. J. West, R. G. Hilton, M. New, A. B. Horwath, J. B. Fisher, J. M. Rapp, A. Robles Caceres, Y. Malhi |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1027-5606
|
Digitales Dokument |
URL |
Erschienen |
In: Hydrology and Earth System Sciences ; 18, no. 12 ; Nr. 18, no. 12 (2014-12-21), S.5377-5397 |
Datensatznummer |
250120576
|
Publikation (Nr.) |
copernicus.org/hess-18-5377-2014.pdf |
|
|
|
Zusammenfassung |
The hydrology of tropical mountain catchments plays a central role in
ecological function, geochemical and biogeochemical cycles, erosion and
sediment production, and water supply in globally important environments.
There have been few studies quantifying the seasonal and annual water
budgets in the montane tropics, particularly in cloud forests. We
investigated the water balance and hydrologic regime of the Kosñipata
catchment (basin area: 164.4 km2) over the period 2010–2011. The
catchment spans over 2500 m in elevation in the eastern Peruvian Andes and
is dominated by tropical montane cloud forest with some high-elevation
puna grasslands. Catchment-wide rainfall was 3112 ± 414 mm yr−1,
calculated by calibrating Tropical Rainfall Measuring Mission (TRMM) 3B43
rainfall with rainfall data from nine meteorological stations in the catchment.
Cloud water input to streamflow was 316 ± 116 mm yr−1 (9.2% of
total inputs), calculated from an isotopic mixing model using deuterium
excess (Dxs) and δD of waters. Field streamflow was measured in
2010 by recording height and calibrating to discharge. River run-off was
estimated to be 2796 ± 126 mm yr−1. Actual evapotranspiration
(AET) was 688 ± 138 mm yr−1, determined using the Priestley and
Taylor–Jet Propulsion Laboratory (PT-JPL) model. The overall water budget
was balanced within 1.6 ± 13.7%. Relationships between monthly
rainfall and river run-off follow an anticlockwise hysteresis through the
year, with a persistence of high run-off after the end of the wet season. The
size of the soil and shallow groundwater reservoir is most likely
insufficient to explain sustained dry-season flow. Thus, the observed
hysteresis in rainfall–run-off relationships is best explained by sustained
groundwater flow in the dry season, which is consistent with the water
isotope results that suggest persistent wet-season sources to streamflow
throughout the year. These results demonstrate the importance of transient
groundwater storage in stabilising the annual hydrograph in this region of
the Andes. |
|
|
Teil von |
|
|
|
|
|
|