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Titel |
Influence of soil, land use and climatic factors on the hydraulic conductivity of soil |
VerfasserIn |
N. Jarvis, J. Koestel, I. Messing, J. Moeys, A. Lindahl |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1027-5606
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Digitales Dokument |
URL |
Erschienen |
In: Hydrology and Earth System Sciences ; 17, no. 12 ; Nr. 17, no. 12 (2013-12-20), S.5185-5195 |
Datensatznummer |
250086038
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Publikation (Nr.) |
copernicus.org/hess-17-5185-2013.pdf |
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Zusammenfassung |
Due to inadequate data support, existing algorithms used to estimate soil
hydraulic conductivity, K, in (eco)hydrological models ignore the effects of
key site factors such as land use and climate and underplay the significant
effects of soil structure on water flow at and near saturation. These
limitations may introduce serious bias and error into predictions of
terrestrial water balances and soil moisture status, and thus plant growth
and rates of biogeochemical processes. To resolve these issues, we collated
a new global database of hydraulic conductivity measured by tension
infiltrometer under field conditions. The results of our analyses on this
data set contrast markedly with those of existing algorithms used to estimate
K. For example, saturated hydraulic conductivity, Ks, in the topsoil
(< 0.3 m depth) was found to be only weakly related to texture.
Instead, the data suggests that Ks depends more strongly on bulk
density, organic carbon content and land use. In this respect, organic
carbon was negatively correlated with Ks, presumably due to water
repellency, while Ks at arable sites was, on average, ca. 2–3 times
smaller than under natural vegetation, forests and perennial agriculture.
The data also clearly demonstrates that clay soils have smaller K in the soil
matrix and thus a larger contribution of soil macropores to K at and near
saturation. |
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