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Titel |
Groundwater-surface water interactions, vegetation dependencies and implications for water resources management in the semi-arid Hailiutu River catchment, China – a synthesis |
VerfasserIn |
Y. Zhou, J. Wenninger, Z. Yang, L. Yin, J. Huang, L. Hou, X. Wang, D. Zhang, S. Uhlenbrook |
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. 7 ; Nr. 17, no. 7 (2013-07-04), S.2435-2447 |
Datensatznummer |
250018914
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Publikation (Nr.) |
copernicus.org/hess-17-2435-2013.pdf |
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Zusammenfassung |
During the last decades, large-scale land use changes took place in the
Hailiutu River catchment, a semi-arid area in northwest China. These changes
had significant impacts on the water resources in the area. Insights into
groundwater and surface water interactions and vegetation-water dependencies
help to understand these impacts and formulate sustainable water resources
management policies. In this study, groundwater and surface water
interactions were identified using the baseflow index at the catchment scale,
and hydraulic and water temperature methods as well as event hydrograph
separation techniques at the sub-catchment scale. The results show that
almost 90% of the river discharge consists of groundwater. Vegetation
dependencies on groundwater were analysed from the relationship between the
Normalized Difference Vegetation Index (NDVI) and groundwater depth at the
catchment scale and along an ecohydrogeological cross-section, and by
measuring the sap flow of different plants, soil water contents and
groundwater levels at different research sites. The results show that all
vegetation types, i.e. trees (willow (Salix matsudana) and poplar
(Populus simonii), bushes (salix – Salix psammophila), and
agricultural crops (maize – Zea mays)), depend largely on
groundwater as the source for transpiration. The comparative analysis
indicates that maize crops use the largest amount of water, followed by
poplar trees, salix bushes, and willow trees. For sustainable water use with
the objective of satisfying the water demand for socio-economical development
and to prevent desertification and ecological impacts on streams, more
water-use-efficient crops such as sorghum, barley or millet should be
promoted to reduce the consumptive water use. Willow trees should be used as
wind-breaks in croplands and along roads, and drought-resistant and less
water-use intensive plants (for instance native bushes) should be used to
vegetate sand dunes. |
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