This title appears in the Scientific Report :
2014
Spatially distributed soil water content in a small forested catchment and its relation to the catchment water bidget on various timescales
Spatially distributed soil water content in a small forested catchment and its relation to the catchment water bidget on various timescales
In the framework of the TERENO project, terrestrial observatories have been implemented in order to observehydrological phenomena at several scales, from small highly instrumented headwater catchments to mesoscalewatersheds. At the headwater catchment scale, field experiments are conducted in which...
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Personal Name(s): | Graf, Alexander (Corresponding Author) |
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Bogena, Heye / Hardelauf, Horst / Pütz, Thomas / Drüe, Clemens / Heinemann, Günther / Vereecken, Harry | |
Contributing Institute: |
Agrosphäre; IBG-3 |
Imprint: |
2014
|
Physical Description: |
13914 |
Conference: | EGU 2014, Vienna (Austria), 2014-04-27 - 2014-05-02 |
Document Type: |
Contribution to a conference proceedings |
Research Program: |
TRR 32: Muster und Strukturen in Boden-Pflanzen-Atmosphären-Systemen: Erfassung, Modellierung und Datenassimilation Terrestrial Systems: From Observation to Prediction Terrestrial Environmental Observatories Modelling and Monitoring Terrestrial Systems: Methods and Technologies |
Publikationsportal JuSER |
In the framework of the TERENO project, terrestrial observatories have been implemented in order to observehydrological phenomena at several scales, from small highly instrumented headwater catchments to mesoscalewatersheds. At the headwater catchment scale, field experiments are conducted in which the effects of land usechange are monitored to provide empirical data describing hydrological processes and responses. The TERENOtest site Wüstebach is a 38.5 ha small forested headwater catchment located in a low mountain range in Germany.For a period of 3 years prior to a partial deforestation in 2013, the catchment hydrology has been characterizedby continuous measurements of runoff (R), actual evapotranspiration based on the eddy-covariance method (ET),and soil water content at 3 depths in 109 locations (). With nearby measurements of precipitation (P), as wellas potential evapotranspiration (PET) for regression-based gap filling of ET, it was possible to analyse the waterbudget without relying on process-based models.The long-term water budget P–ET–R was closed with a residual of less than 3% of annual precipitation. Onthe daily timescale, the increasing residual of the water budget was explained to a moderate extent by soilwater content (R2 = 0.40). Wavelet coherence analysis revealed timescales of about 4 days and less, which werepresumably dominated by unaccounted fast-turnover storage terms such as interception, as a major source ofuncertainty. At weekly resolution, soil water storage explained more than half (R2 = 0.62) of the water budgetresidual. By means of a combined empirical orthogonal function and cluster analysis, differences in the spatialpattern of soil water content between wet and dry state (above and below 0.35 cm3/cm3 spatially averaged soilwater content) of the catchment could be identified. Various analyses confirmed that ET was predominantlyenergy-limited, but gradually lost coherence with PET and thus energy supply during the dry state, especiallyduring and after the dry spring 2011. |