Abstract

This investigation quantifies how temperatures in the streambed sediments of a karst stream fluctuate in relation to discharge, seasonal, and diurnal temperature variations as the stream passes through a karst window. Furthermore, the linkages between meteorological processes and temperature variation in the hyporheic zone are delineated. Examination of a high-resolution, three dimensional record of temperature variation in a karst stream substrate provides insight into thermal disturbances in the hyporheic zone. Temperatures in the upper portion of the hyporheic zone are strongly linked to air temperatures via the surface water. The variation is considerably less as depth increases. The annual temperature variation in the lower portion of the shallow hyporheic zone is reduced by one-third, relative to the variation observed in the surface water and upper substrate. During storm events, the upper portion (0-5 cm) of the shallow hyporheic zone is subject to a thermal regime very similar to surface stream water. However, below these depths the sharpest temperature fluctuations are effectively muted within the stream substrate. More frequent diurnal variations, particularly those associated with baseflow conditions, are also dampened within the substrate.

Document Type

Article

Additional Information

Re-published from Speleogenesis and Evolution of Karst Aquifers (ISSN 1814-294X) 3, no. 1 (2005)

DOI

https://dx.doi.org/10.5038/1827-806X.35.2.1

Rights Information

© 2006 the authors. International Journal of Speleology is published under a Creative Commons Attribution-NonCommercial 4.0 International.

Keywords

hyporheic, thermal variation, stream

Publication Date

6-1-2006

Journal Title

International Journal of Speleology

Share

COinS