Effects of bottom sediment restoration on interstitial habitat characteristics and benthic macroinvertebrate assemblages in a headwater stream
Article first published online: 21 JUN 2007
Copyright © 2007 John Wiley & Sons, Ltd.
River Research and Applications
Volume 23, Issue 8, pages 815–828, October 2007
How to Cite
Sarriquet, P. E., Bordenave, P. and Marmonier, P. (2007), Effects of bottom sediment restoration on interstitial habitat characteristics and benthic macroinvertebrate assemblages in a headwater stream. River Res. Applic., 23: 815–828. doi: 10.1002/rra.1013
- Issue published online: 6 OCT 2007
- Article first published online: 21 JUN 2007
- Manuscript Accepted: 1 FEB 2007
- Manuscript Revised: 23 JAN 2007
- Manuscript Received: 18 JUL 2006
- French Ministry of the ‘Ecology and Sustainable Development’. Grant Number: 5000346
- sediment clogging;
- hyporheic zone;
The restoration of in-stream habitats by structural improvement of stream beds is more and more frequent, but the ecological consequences of such works are still little known. We have examined the influence of the deposit of a 15 cm gravel layer over the stream bottom on the chemical characteristics of the interstitial water, the sediment grain size and the composition of the benthic assemblages. We have compared a restored reach to an upstream control over three years and at three seasons each year. Dissolved oxygen, ammonium, nitrite and nitrate contents were measured in both surface and interstitial (−15 cm deep) waters, together with the depth of anoxia estimated using wooden stakes and fine sediment content at the surface. During the same period and seasons, benthic invertebrates were sampled at five points in each reach. The restoration induced an increase in vertical exchanges of water between surface and interstitial habitats, with an increase in the depth of hypoxia. Changes were observed in the composition of invertebrate communities, but not in the density or in the taxonomic richness of assemblages. These changes in assemblages were fragile: a local disturbance (such as a drying period) diminished the beneficial effect of the restoration with the disappearance of several organisms. The viability of such restoration works may be associated with catchment management designed to reduce fine sediment inputs to the river. Copyright © 2007 John Wiley & Sons, Ltd.