Contrasting Behaviour of Two Riparian Wetlands in Relation to their Location in the Hydrographic Network

TitleContrasting Behaviour of Two Riparian Wetlands in Relation to their Location in the Hydrographic Network
Publication TypeJournal Article
Year of Publication2011
AuthorsMontreuil O., Cudennec C., Merot P.
JournalJournal of Hydrology
Volume406
Pagination39-53
Date PublishedAug 18
ISBN Number0022-1694
Accession NumberWOS:000294518500004
Keywordsagricultural watersheds, buffer zone, buffer zones, floodplain hydrology, flow path, garonne river, landscape controls, nitrate, nitrate removal, nitrogen dynamics, riparian zone, stream, stream order, water-table fluctuations, wetland
Abstract

Although many studies have focused on the hydrological behaviour and classification of wetlands, the wide diversity of wetlands makes a clear and operational view difficult. The objective of this work is to compare the organisation and behaviour of two riparian wetlands (RWs) located, respectively, along Strahler order-2 and order-5 streams of the Scorff River catchment (Brittany, France). Groundwater table dynamics were monitored at the RWs during one hydrological year. Hydrochemistry was characterised during hydrological periods of high and low hydraulic head. The results show clearly the contrast in geomorphological and pedological organisation between the two RWs. In addition, the RW along an order-2 stream exhibited a strong hydrological connectivity with the adjacent hillslope whereas the RW along an order-5 stream showed a strong hydrological connectivity with the adjacent stream. We also observed the contrast between conditions favourable for high and permanent denitrification but on low nitrogen fluxes for order 2, and conditions less favourable to denitrification but on strong nitrogen fluxes for order 5. The relation between the contrasting hydrological and hydrochemical behaviour of these two RWs and their stream orders is discussed from the literature and local observations of the catchment. The results support the hypothesis of a relation between stream order and the hydrological and hydrochemical behaviour of the RWs and thus a catchment-scale organisation which may be taken into consideration in management strategies. (C) 2011 Elsevier B.V. All rights reserved.

Short TitleJ Hydrol
Alternate JournalJ Hydrol