Sampling frequency trade-offs in the assessment of mean transit times of tropical montane catchment waters under semi-steady-state conditions

Precipitation event samples and weekly based water samples from streams and soils were collected in a tropical montane cloud forest catchment for 2 years and analyzed for stable water isotopes in order to understand the effect of sampling frequency in the performance of three lumped-parameter distri...

Full description

Bibliographic Details
Main Authors: E. Timbe, D. Windhorst, R. Celleri, L. Timbe, P. Crespo, H.-G. Frede, J. Feyen, L. Breuer
Format: Article
Language:English
Published: Copernicus Publications 2015-03-01
Series:Hydrology and Earth System Sciences
Online Access:http://www.hydrol-earth-syst-sci.net/19/1153/2015/hess-19-1153-2015.pdf
_version_ 1811198403090055168
author E. Timbe
D. Windhorst
R. Celleri
L. Timbe
P. Crespo
H.-G. Frede
J. Feyen
L. Breuer
author_facet E. Timbe
D. Windhorst
R. Celleri
L. Timbe
P. Crespo
H.-G. Frede
J. Feyen
L. Breuer
author_sort E. Timbe
collection DOAJ
description Precipitation event samples and weekly based water samples from streams and soils were collected in a tropical montane cloud forest catchment for 2 years and analyzed for stable water isotopes in order to understand the effect of sampling frequency in the performance of three lumped-parameter distribution functions (exponential-piston flow, linear-piston flow and gamma) which were used to estimate mean transit times of waters. Precipitation data, used as input function for the models, were aggregated to daily, weekly, bi-weekly, monthly and bi-monthly sampling resolutions, while analyzed frequencies for outflows went from weekly to bi-monthly. By using different scenarios involving diverse sampling frequencies, this study reveals that the effect of lowering the sampling frequency depends on the water type. For soil waters, with transit times on the order of few weeks, there was a clear trend of over predictions. In contrast, the trend for stream waters, which have a more damped isotopic signal and mean transit times on the order of 2 to 4 years, was less clear and showed a dependence on the type of model used. The trade-off to coarse data resolutions could potentially lead to misleading conclusions on how water actually moves through the catchment, notwithstanding that these predictions could reach better fitting efficiencies, fewer uncertainties, errors and biases. For both water types an optimal sampling frequency seems to be 1 or at most 2 weeks. The results of our analyses provide information for the planning of future fieldwork in similar Andean or other catchments.
first_indexed 2024-04-12T01:29:23Z
format Article
id doaj.art-454711776a5a462da9f9b032e3a8cf64
institution Directory Open Access Journal
issn 1027-5606
1607-7938
language English
last_indexed 2024-04-12T01:29:23Z
publishDate 2015-03-01
publisher Copernicus Publications
record_format Article
series Hydrology and Earth System Sciences
spelling doaj.art-454711776a5a462da9f9b032e3a8cf642022-12-22T03:53:31ZengCopernicus PublicationsHydrology and Earth System Sciences1027-56061607-79382015-03-011931153116810.5194/hess-19-1153-2015Sampling frequency trade-offs in the assessment of mean transit times of tropical montane catchment waters under semi-steady-state conditionsE. Timbe0D. Windhorst1R. Celleri2L. Timbe3P. Crespo4H.-G. Frede5J. Feyen6L. Breuer7Departamento de Recursos Hídricos y Ciencias Ambientales, Universidad de Cuenca, Cuenca, EcuadorInstitute for Landscape Ecology and Resources Management (ILR), Research Centre for Bio Systems, Land Use and Nutrition (IFZ), Justus-Liebig-Universität Gießen, Gießen, GermanyDepartamento de Recursos Hídricos y Ciencias Ambientales, Universidad de Cuenca, Cuenca, EcuadorDepartamento de Recursos Hídricos y Ciencias Ambientales, Universidad de Cuenca, Cuenca, EcuadorDepartamento de Recursos Hídricos y Ciencias Ambientales, Universidad de Cuenca, Cuenca, EcuadorInstitute for Landscape Ecology and Resources Management (ILR), Research Centre for Bio Systems, Land Use and Nutrition (IFZ), Justus-Liebig-Universität Gießen, Gießen, GermanyDepartamento de Recursos Hídricos y Ciencias Ambientales, Universidad de Cuenca, Cuenca, EcuadorInstitute for Landscape Ecology and Resources Management (ILR), Research Centre for Bio Systems, Land Use and Nutrition (IFZ), Justus-Liebig-Universität Gießen, Gießen, GermanyPrecipitation event samples and weekly based water samples from streams and soils were collected in a tropical montane cloud forest catchment for 2 years and analyzed for stable water isotopes in order to understand the effect of sampling frequency in the performance of three lumped-parameter distribution functions (exponential-piston flow, linear-piston flow and gamma) which were used to estimate mean transit times of waters. Precipitation data, used as input function for the models, were aggregated to daily, weekly, bi-weekly, monthly and bi-monthly sampling resolutions, while analyzed frequencies for outflows went from weekly to bi-monthly. By using different scenarios involving diverse sampling frequencies, this study reveals that the effect of lowering the sampling frequency depends on the water type. For soil waters, with transit times on the order of few weeks, there was a clear trend of over predictions. In contrast, the trend for stream waters, which have a more damped isotopic signal and mean transit times on the order of 2 to 4 years, was less clear and showed a dependence on the type of model used. The trade-off to coarse data resolutions could potentially lead to misleading conclusions on how water actually moves through the catchment, notwithstanding that these predictions could reach better fitting efficiencies, fewer uncertainties, errors and biases. For both water types an optimal sampling frequency seems to be 1 or at most 2 weeks. The results of our analyses provide information for the planning of future fieldwork in similar Andean or other catchments.http://www.hydrol-earth-syst-sci.net/19/1153/2015/hess-19-1153-2015.pdf
spellingShingle E. Timbe
D. Windhorst
R. Celleri
L. Timbe
P. Crespo
H.-G. Frede
J. Feyen
L. Breuer
Sampling frequency trade-offs in the assessment of mean transit times of tropical montane catchment waters under semi-steady-state conditions
Hydrology and Earth System Sciences
title Sampling frequency trade-offs in the assessment of mean transit times of tropical montane catchment waters under semi-steady-state conditions
title_full Sampling frequency trade-offs in the assessment of mean transit times of tropical montane catchment waters under semi-steady-state conditions
title_fullStr Sampling frequency trade-offs in the assessment of mean transit times of tropical montane catchment waters under semi-steady-state conditions
title_full_unstemmed Sampling frequency trade-offs in the assessment of mean transit times of tropical montane catchment waters under semi-steady-state conditions
title_short Sampling frequency trade-offs in the assessment of mean transit times of tropical montane catchment waters under semi-steady-state conditions
title_sort sampling frequency trade offs in the assessment of mean transit times of tropical montane catchment waters under semi steady state conditions
url http://www.hydrol-earth-syst-sci.net/19/1153/2015/hess-19-1153-2015.pdf
work_keys_str_mv AT etimbe samplingfrequencytradeoffsintheassessmentofmeantransittimesoftropicalmontanecatchmentwatersundersemisteadystateconditions
AT dwindhorst samplingfrequencytradeoffsintheassessmentofmeantransittimesoftropicalmontanecatchmentwatersundersemisteadystateconditions
AT rcelleri samplingfrequencytradeoffsintheassessmentofmeantransittimesoftropicalmontanecatchmentwatersundersemisteadystateconditions
AT ltimbe samplingfrequencytradeoffsintheassessmentofmeantransittimesoftropicalmontanecatchmentwatersundersemisteadystateconditions
AT pcrespo samplingfrequencytradeoffsintheassessmentofmeantransittimesoftropicalmontanecatchmentwatersundersemisteadystateconditions
AT hgfrede samplingfrequencytradeoffsintheassessmentofmeantransittimesoftropicalmontanecatchmentwatersundersemisteadystateconditions
AT jfeyen samplingfrequencytradeoffsintheassessmentofmeantransittimesoftropicalmontanecatchmentwatersundersemisteadystateconditions
AT lbreuer samplingfrequencytradeoffsintheassessmentofmeantransittimesoftropicalmontanecatchmentwatersundersemisteadystateconditions