Hydromorphological conditions in eighteen restored floodplain
channels of a large river: linking patterns to processes

J 2015

Hydromorphological conditions in eighteen restored floodplain channels of a large river: linking patterns to processes

RIQUIER, Jéremie; Hervé PIÉGAY and Monika ŠULC MICHALKOVÁ

Basic information

Original name

Hydromorphological conditions in eighteen restored floodplain channels of a large river: linking patterns to processes

Authors

RIQUIER, Jéremie (250 France, guarantor); Hervé PIÉGAY (250 France) and Monika ŠULC MICHALKOVÁ (703 Slovakia, belonging to the institution)

Edition

Freshwater Biology, Danvers, Blackwell Science, 2015, 0046-5070

Other information

Language

English

Type of outcome

Article in a journal

Field of Study

10501 Hydrology

Country of publisher

United States of America

Confidentiality degree

is not subject to a state or trade secret

References:

URL

Impact factor

Impact factor: 2.933

RIV identification code

RIV/00216224:14310/15:00082641

Organization unit

Faculty of Science

DOI

http://dx.doi.org/10.1111/fwb.12411

UT WoS

000354254800002

EID Scopus

2-s2.0-84929659912

Keywords (in Czech)

povodňový režim, funkční typologie, velikost zrna, hydrologická konektivita, Rhôna

Keywords in English

flooding regime;functional typology;grain size;hydrological connectivity;Rhône

Abstract

ORIG CZ

In the original language

1.Over the past few decades, numerous floodplain restoration projects have attempted to re-establish complex and diverse river floodplains. They often aim to restore lateral connectivity (i.e. interactions between the main river channel and floodplain channels) and rejuvenate floodplain habitats which are no longer maintained or created by fluvial processes. Nonetheless, results of these experiences in terms of hydromorphological conditions and adjustments are rarely shared. The Rhône River is a large, highly regulated system where lateral connectivity has been greatly reduced. We investigated habitat dynamics (using sedimentological indicators as proxies) in 18 floodplain channels that were restored between 1999 and 2006. Environmental data (bathymetry and grain size of surficial fine sediments) were acquired on 3–5 surveys for each channel covering 6–12 years after restoration. In addition, a pre-restoration survey was made in 12 of the 18 channels. Using pressure sensors in the floodplain channels and rating curves in the main channel, we quantified the upstream overflow frequency and magnitude (i.e. maximum shear stress) in the channels and tested how these variables explain observed sedimentological patterns. Between-channel diversity accounted for 81% of the sedimentological variability observed after restoration. Time-averaged sedimentological conditions were robust and well predicted from overflow frequency and magnitude. Similarly, an indirect index of lateral connectivity used by hydrobiologists was also predictable from overflow frequency and magnitude. The remaining 19% of the sedimentological variability was attributed to temporal variation within channels and was mainly related to changes in longitudinal grain size gradient. This emphasises that grain size patterns are periodically reworked as a result of the flooding regime (backflow versus overflow) without significantly affecting average grain sizes. However, trajectories of grain size changes were stochastic and not always related to the hydrological regime. Accordingly, the partial pre-restoration data suggest that post-restoration sedimentological conditions were often similar to those observed before restoration, except in a few channels where major restoration works were performed. Our results quantify how changes in upstream overflow frequency and magnitude can modify physical conditions in the floodplain channels. They can be used to design habitats that are infrequent or missing at the floodplain scale. These results also suggest that changes in upstream plug morphology are a primary habitat driver. Such changes could be more frequently implemented in the Rhône and elsewhere to maximise the diversity of physical conditions in floodplains.

In Czech

Článek sleduje vývoj a hydromorfologické podmínky 18 odřezaných koryt řeky Rhôny a jejich hydrologickou konktivitu.

Cite

RIQUIER, Jéremie; Hervé PIÉGAY and Monika ŠULC MICHALKOVÁ. Hydromorphological conditions in eighteen restored floodplain channels of a large river: linking patterns to processes. Freshwater Biology. Danvers: Blackwell Science, 2015, vol. 60, No 6, p. 1085-1103. ISSN 0046-5070. Available from: https://dx.doi.org/10.1111/fwb.12411.

@article{1232848,
   author = {Riquier, Jéremie and Piégay, Hervé and Šulc Michalková, Monika},
   article_location = {Danvers},
   article_number = {6},
   doi = {http://dx.doi.org/10.1111/fwb.12411},
   keywords = {flooding regime;functional typology;grain size;hydrological connectivity;Rhône},
   language = {eng},
   issn = {0046-5070},
   journal = {Freshwater Biology},
   title = {Hydromorphological conditions in eighteen restored floodplain channels of a large river: linking patterns to processes},
   url = {http://onlinelibrary.wiley.com/doi/10.1111/fwb.12411/abstract},
   volume = {60},
   year = {2015}
}

TY  - JOUR
ID  - 1232848
AU  - Riquier, Jéremie - Piégay, Hervé - Šulc Michalková, Monika
PY  - 2015
TI  - Hydromorphological conditions in eighteen restored floodplain channels of a large river: linking patterns to processes
JF  - Freshwater Biology
VL  - 60
IS  - 6
SP  - 1085-1103
EP  - 1085-1103
PB  - Blackwell Science
SN  - 00465070
KW  - flooding regime;functional typology;grain size;hydrological connectivity;Rhône
UR  - http://onlinelibrary.wiley.com/doi/10.1111/fwb.12411/abstract
L2  - http://onlinelibrary.wiley.com/doi/10.1111/fwb.12411/abstract
N2  - 1.Over the past few decades, numerous floodplain restoration projects have attempted to re-establish complex and diverse river floodplains. They often aim to restore lateral connectivity (i.e. interactions between the main river channel and floodplain channels) and rejuvenate floodplain habitats which are no longer maintained or created by fluvial processes. Nonetheless, results of these experiences in terms of hydromorphological conditions and adjustments are rarely shared. The Rhône River is a large, highly regulated system where lateral connectivity has been greatly reduced. We investigated habitat dynamics (using sedimentological indicators as proxies) in 18 floodplain channels that were restored between 1999 and 2006. Environmental data (bathymetry and grain size of surficial fine sediments) were acquired on 3–5 surveys for each channel covering 6–12 years after restoration. In addition, a pre-restoration survey was made in 12 of the 18 channels. Using pressure sensors in the floodplain channels and rating curves in the main channel, we quantified the upstream overflow frequency and magnitude (i.e. maximum shear stress) in the channels and tested how these variables explain observed sedimentological patterns. Between-channel diversity accounted for 81% of the sedimentological variability observed after restoration. Time-averaged sedimentological conditions were robust and well predicted from overflow frequency and magnitude. Similarly, an indirect index of lateral connectivity used by hydrobiologists was also predictable from overflow frequency and magnitude. The remaining 19% of the sedimentological variability was attributed to temporal variation within channels and was mainly related to changes in longitudinal grain size gradient. This emphasises that grain size patterns are periodically reworked as a result of the flooding regime (backflow versus overflow) without significantly affecting average grain sizes. However, trajectories of grain size changes were stochastic and not always related to the hydrological regime. Accordingly, the partial pre-restoration data suggest that post-restoration sedimentological conditions were often similar to those observed before restoration, except in a few channels where major restoration works were performed. Our results quantify how changes in upstream overflow frequency and magnitude can modify physical conditions in the floodplain channels. They can be used to design habitats that are infrequent or missing at the floodplain scale. These results also suggest that changes in upstream plug morphology are a primary habitat driver. Such changes could be more frequently implemented in the Rhône and elsewhere to maximise the diversity of physical conditions in floodplains.
ER  -

RIQUIER, Jéremie; Hervé PIÉGAY and Monika ŠULC MICHALKOVÁ. Hydromorphological conditions in eighteen restored floodplain channels of a large river: linking patterns to processes. \textit{Freshwater Biology}. Danvers: Blackwell Science, 2015, vol.~60, No~6, p.~1085-1103. ISSN~0046-5070. Available from: https://dx.doi.org/10.1111/fwb.12411.

Přehled o publikaci