TY  - JOUR
A1  - Zimmermann, Alexander
A1  - Schinn, Dustin S.
A1  - Francke, Till
A1  - Elsenbeer, Helmut
A1  - Zimmermann, Beate
T1  - Uncovering patterns of near-surface saturated hydraulic conductivity in an overland flow-controlled landscape
T2  - Geoderma : an international journal of soil science
N2  - Saturated hydraulic conductivity (K-s) is an important soil characteristic affecting soil water storage, runoff generation and erosion processes. In some areas where high-intensity rainfall coincides with low K-s values at shallow soil depths, frequent overland flow entails dense drainage networks. Consequently, linear structures such as flowlines alternate with inter-flowline areas. So far, investigations of the spatial variability of K-s mainly relied on isotropic covariance models which are unsuitable to reveal patterns resulting from linear structures. In the present study, we applied two sampling approaches so as to adequately characterize K-s spatial variability in a tropical forest catchment that features a high density of flowlines: A classical nested sampling survey and a purposive sampling strategy adapted to the presence of flowlines. The nested sampling approach revealed the dominance of small-scale variability, which is in line with previous findings. Our purposive sampling, however, detected a strong spatial gradient: surface K-s increased substantially as a function of distance to flowline; 10 m off flowlines, values were similar to the spatial mean of K-s. This deterministic trend can be included as a fixed effect in a linear mixed modeling framework to obtain realistic spatial fields of K-s. In a next step we used probability maps based on those fields and prevailing rainfall intensities to assess the hydrological relevance of the detected pattern. This approach suggests a particularly good agreement between the probability statements of K-s exceedance and observed overland flow occurrence during wet stages of the rainy season.
KW  - Soil hydrology
KW  - Saturated hydraulic conductivity
KW  - Overland flow generation
KW  - Spatial patterns
KW  - Drainage network
Y1  - 2013
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/35180
SN  - 0016-7061
VL  - 195
IS  - 169
SP  - 1
EP  - 11
PB  - Elsevier
CY  - Amsterdam
ER  -