Article ID Journal Published Year Pages File Type
4577164 Journal of Hydrology 2012 8 Pages PDF
Abstract

SummaryKnowledge of soil moisture is critical to understanding many of the hydrological processes that are of interest in soil hydrology, meteorology, and ecology research. In the present study, we used rainfall and soil moisture data from 2003 to 2008 measured at grassland and meadow sites in the Qilian Mountains of northwestern China to analyze the response of soil moisture to rainfall event size during the growing season. The responses of soil moisture at the grassland and meadow sites to rainfall event size were similar, although total rainfall, the frequency of large rainfall events, and the vegetation types were different. Soil moisture at depths of 20 and 40 cm increased significantly after rainfall events larger than 15 and 20 mm, respectively, but the magnitude of these changes varied in response to differences in the duration of the dry interval preceding the rain. Soil moisture at depths from 60 to 80 cm in the grassland increased obviously with rainfall events larger than 40 mm or after two consecutive large rainfall events, but was not significantly correlated with rainfall event size in the meadow. Soil moisture at depths from 120 to 160 cm did not change significantly during the growing season at either site. The soil water storage at depths from 20 to 80 cm at both sites increased obviously after rainfall events larger than 20 mm. The present results suggest that large rainfall events (>20 mm) play a key role in increasing soil water storage in the grassland and meadow ecosystems of these semi-arid mountains.

► We analyzed the response of soil moistures to different rainfall event sizes. ► Responses of soil moisture in grassland and meadow to rain event size were similar. ► Large rainfall event (>20 mm) play a key role to supply soil water storage.

Related Topics
Physical Sciences and Engineering Earth and Planetary Sciences Earth-Surface Processes
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