Flow variability and the ecology of large rivers

1998 ◽  
Vol 49 (1) ◽  
pp. 55 ◽  
Author(s):  
J. T. Puckridge ◽  
F. Sheldon ◽  
K. F. Walker ◽  
A. J. Boulton
Keyword(s):  
Flood Pulse ◽  
Large Rivers ◽  
Ecological Processes ◽  
Flood Pulse Concept ◽  
Significant Information ◽  
Flow Variability ◽  
Climatic Regions ◽  
Hydrological Variability ◽  
River Types ◽  
River Conservation

Ecological processes in large rivers are controlled by their flow variability. However, it is difficult to find measures of hydrological variability that characterize groups of rivers and can also be used to generate hypotheses about their ecology. Multivariate analyses of the hydrographs of 52 rivers worldwide revealed distinctive patterns of flow variability that were often correlated with climate. For example, there were groups of rivers that corresponded broadly with ‘tropical’ and ‘dryland’ climates. However, some rivers from continental climates occupy both extremes of this range, illustrating the limitations of simple classification. Individual rivers and groups of rivers may also have different hydrographic ‘signatures’, and attempts to combine measures of hydrological variability into indices mask biologically significant information. This paper identifies 11 relatively independent measures of hydrological variability that help categorize river types and are each associated with aspects of fish biology. Ways are suggested by which the Flood Pulse Concept can be expanded to encompass hydrological variability and accommodate differences among groups of rivers from different climatic regions. Such recognition of the complex role of hydrological variability enhances the value of the concept for river conservation, management and restoration.

scholarly journals Effectiveness of Flexible Dam Operation and Sediment Replenishment at Managawa Dam, Japan

2018 ◽  
Vol 13 (4) ◽  
pp. 691-701 ◽  
Author(s):  
Katsumi Matsushima ◽  
Makoto Hyodo ◽  
Noriyuki Shibata ◽  
Yoshihiro Shimizu ◽  
◽  
...  
Keyword(s):  
Flood Pulse ◽  
Demonstration Project ◽  
Scale Analysis ◽  
Management Options ◽  
Ecological Processes ◽  
Fluvial Systems ◽  
Macro Scale ◽  
Dam Operation ◽  
The Impact ◽  
The Relationship

A field demonstration project on flexible dam operation at the Managawa dam in the Kuzuryu River Basin has been implemented since 2000. The goal is to restore flow and sediment regimes in the Managawa River, which flows along the Ono-city and is located below the dam. Flexible dam operation stores inflow discharge into a reservoir, which generally uses part of the flood control capacity and appropriately discharges the stored water to the river, also known as the “flood pulse,” for restoring dynamic fluvial systems and the resulting ecological processes. In addition, other options have been carried out in combination with flexible dam operation, for example, sediment replenishment since 2003 and channel rehabilitation since 2007. This article reveals the positive impacts and effectiveness of flexible dam operation, sediment replenishment, and channel rehabilitation, and discusses challenges and future prospects toward translating the field demonstration project into dam management on the ground level. First, we classified reach types to identify the impact of various management options, e.g., flexible dam operation, sediment replenishment, and channel rehabilitation. These management options can influence respected reaches. We conducted a macro-scale analysis to understand the relationship between the aforementioned management options and dynamic fluvial systems, addressing changes in gravel riverbed, vegetation, and habitat types (riffles and pools). Second, a micro-scale analysis was conducted to understand the relationship between the management option and changes in attached algae to sediment and macro-invertebrates, etc. The results show the effectiveness of the middle-scale flood pulse to restore dynamic fluvial systems, increase habitat diversity, and sustain ecological processes. Furthermore, we discussed the impacts of such options on the flow and sediment regimes in Managawa River and revealed that flexible dam operation reduces the occurrence of low flow and midscale floods. It was also revealed methods such as sediment replenishment and channel rehabilitation play an important role in increasing the effectiveness of the middle-scale flood pulse and restoring dynamic fluvial systems, even though sediment replenishment is not sufficient to restore sediment regimes (i.e., bring then back to pre-dam conditions).

A new look at the Flood Pulse Concept: The (ir)relevance of the moving littoral in temperate zone rivers

2014 ◽  
Vol 64 ◽  
pp. 85-99 ◽  
Author(s):  
F.M. Keizer ◽  
P.P. Schot ◽  
T. Okruszko ◽  
J. Chormański ◽  
I. Kardel ◽  
...  
Keyword(s):  
Flood Pulse ◽  
Temperate Zone ◽  
Flood Pulse Concept ◽  
New Look

Short-term growth (RNA/DNA ratio) of yellow perch (Perca flavescens) in relation to environmental influences and spatio-temporal variation in a shallow fluvial lake

2007 ◽  
Vol 64 (12) ◽  
pp. 1646-1655 ◽  
Author(s):  
Hélène Glémet ◽  
Marco A Rodríguez
Keyword(s):  
Temporal Variation ◽  
Water Level ◽  
Yellow Perch ◽  
Perca Flavescens ◽  
Negative Influence ◽  
Water Levels ◽  
Short Term ◽  
Ecological Processes ◽  
Flood Pulse Concept ◽  
Spatio Temporal

Shallow fluvial lakes are heterogeneous ecosystems in which marked spatio-temporal variation renders difficult the analysis of key ecological processes, such as growth. In this study, we used generalized additive modelling of the RNA/DNA ratio, an index of short-term growth, to investigate the influence of environmental variables and spatio-temporal variation on growth of yellow perch (Perca flavescens) in Lake St. Pierre, Quebec, Canada. Temperature and water level had seemingly stronger effects on short-term growth than seasonal change or spatial variation between and along the lakeshores. Consistent with previous studies, the maximum RNA/DNA ratio was found at 20.5 °C, suggesting that our approach provides a useful tool for estimating thermal optima for growth in the field. The RNA/DNA ratio showed a positive relationship with water level, as predicted by the flood pulse concept, a finding with implications for ecosystem productivity in fluvial lakes. The RNA/DNA ratio was more variable along the north than the south shore, possibly reflecting exposure to more differentiated water masses. The negative influence of both high temperatures and low water levels on growth points to potential impacts of climatic change on fish production in shallow fluvial lakes.

scholarly journals Dispersal phenology of hydrochorous plants in relation to discharge, seed release time and buoyancy of seeds: the flood pulse concept supported

2004 ◽  
Vol 92 (5) ◽  
pp. 786-796 ◽  
Author(s):  
GER BOEDELTJE ◽  
JAN P. BAKKER ◽  
ALBERT TEN BRINKE ◽  
JAN M. VAN GROENENDAEL ◽  
MARTIN SOESBERGEN
Keyword(s):  
Flood Pulse ◽  
Release Time ◽  
Flood Pulse Concept

An extension of the flood pulse concept

2000 ◽  
Vol 14 (16-17) ◽  
pp. 2861-2883 ◽  
Author(s):  
K. Tockner ◽  
F. Malard ◽  
J. V. Ward
Keyword(s):  
Flood Pulse ◽  
Flood Pulse Concept

Evaluation of the flood-pulse concept based on statistical models of growth of selected fishes of the Upper Mississippi River system

1999 ◽  
Vol 56 (12) ◽  
pp. 2282-2291 ◽  
Author(s):  
Steve Gutreuter ◽  
Andrew D Bartels ◽  
Kevin Irons ◽  
Mark B Sandheinrich
Keyword(s):  
Mississippi River ◽  
Littoral Zone ◽  
Micropterus Salmoides ◽  
Lepomis Macrochirus ◽  
River System ◽  
Flood Pulse ◽  
Upper Mississippi River ◽  
Flood Pulse Concept ◽  
Extreme Flood ◽  
Upper Mississippi River System

The flood-pulse concept (FPC) states that annual inundation is the principal force responsible for productivity and biotic interactions in river-floodplain systems. Somatic growth is one component of production, and we hypothesized that, if the FPC applies, growth of fishes that use the moving littoral zone should differ among years with differing flood pattern, whereas nonlittoral fishes would show no such response. Growth of largemouth bass (Micropterus salmoides) and bluegill (Lepomis macrochirus), species that exploit littoral resources, increased during a year having an unusual warm-season flood in the Upper Mississippi River system and was reduced during low-water years. Growth of white bass (Morone chrysops), which do not rely heavily on the littoral zone, did not differ significantly between the extreme-flood and low-water years. Patterns of growth of black crappie (Pomoxis nigromaculatus), which have intermediate dependence on the moving littoral zone, were somewhat ambiguous. These results are consistent with the hypothesis that the FPC applies, at least under certain conditions, to this temperate river system. Our results can also provide an important basis from which to assess some costs and benefits of water level management strategies in large regulated temperate rivers.

Three Dimensions of the Ecological Connectivity of Fluvial Greenway

2014 ◽  
Vol 1065-1069 ◽  
pp. 2785-2788
Author(s):  
Shuai Sun
Keyword(s):  
Cross Section ◽  
Flood Pulse ◽  
Three Dimensions ◽  
Flood Pulse Concept ◽  
Lateral Connectivity ◽  
Multiple Dimensions ◽  
Longitudinal Connectivity ◽  
Natural Flow ◽  
Section Design ◽  
River Cross Section

Fluvial greenway connectivity has multiple dimensions, so it is the complex ecosystems of nature. The longitudinal connectivity of fluvial greenway is directly related to the natural flow of water, and is sensible and cognizable. The lateral Connectivity of fluvial greenway is closely linked to the Flood Pulse Concept and river cross-section design. The vertical connectivity of fluvial greenway refers to the vertical materials and energy circulation performance and the biocoenosis relevancy in the cross section of the river. They constitute the complicated continuum system of fluvial greenway.

scholarly journals Flood Pulsing in the Sudd Wetland: Analysis of Seasonal Variations in Inundation and Evaporation in South Sudan

2012 ◽  
Vol 16 (1) ◽  
pp. 1-19 ◽  
Author(s):  
L-M. Rebelo ◽  
G. B. Senay ◽  
M. P. McCartney
Keyword(s):  
South Sudan ◽  
Open Water ◽  
Flood Pulse ◽  
Economic Benefits ◽  
Floodplain Wetlands ◽  
African Countries ◽  
Ecological Processes ◽  
Development Interventions ◽  
Distribution Of Values ◽  
Baseline Information

Abstract Located on the Bahr el Jebel in South Sudan, the Sudd is one of the largest floodplain wetlands in the world. Seasonal inundation drives the hydrologic, geomorphological, and ecological processes, and the annual flood pulse is essential to the functioning of the Sudd. Despite the importance of the flood pulse, various hydrological interventions are planned upstream of the Sudd to increase economic benefits and food security. These will not be without consequences, in particular for wetlands where the biological productivity, biodiversity, and human livelihoods are dependent on the flood pulse and both the costs and benefits need to be carefully evaluated. Many African countries still lack regional baseline information on the temporal extent, distribution, and characteristics of wetlands, making it hard to assess the consequences of development interventions. Because of political instability in Sudan and the inaccessible nature of the Sudd, recent measurements of flooding and seasonal dynamics are inadequate. Analyses of multitemporal and multisensor remote sensing datasets are presented in this paper, in order to investigate and characterize flood pulsing within the Sudd wetland over a 12-month period. Wetland area has been mapped along with dominant components of open water and flooded vegetation at five time periods over a single year. The total area of flooding (both rain and river fed) over the 12 months was 41 334 km2, with 9176 km2 of this constituting the permanent wetland. Mean annual total evaporation is shown to be higher and with narrower distribution of values from areas of open water (1718 mm) than from flooded vegetation (1641 mm). Although the exact figures require validation against ground-based measurements, the results highlight the relative differences in inundation patterns and evaporation across the Sudd.

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