Flood Plain Form, Function, and Connectivity in River Restoration
Kirsty Bramlett
University of New Mexico
River Restoration
Spring, 2012
Abstract.
Keywords:
Introduction
Floodplains are the areas of land lateral to a river that are inundated with water during a time when
flow has been increased such as a flooding event, during snowpack runoff, or fed through groundwater
and is separated from the main channel of flow of the river. These areas provide many vital functions to
the river by providing nutrients (foodweb), improving water quality(water quality), and also serve as a
habitat(physical habitat) that is high in biodiversity. In their natural state, flood plains are amongst the
most dynamic and heterogeneous ecosystems, showing complex patterns of variation over a wide range
of temporal and spatial scales (Tockner, Lorang and Stanford 77). Floodplains have many definitions and
delineations, which creates a challenge in studying these biomes that are neither entirely aquatic nor
terrestrial. Even the river continuum concept, which described trends in processes from headwaters to a
large river, did not incorporate the floodplain influence (Vannote et al. 1980; but see Cummins et al.
1983 and Sedell et al. 1989; Benke 225). Floodplains had in the past been limited in definition to the
area that is covered by water up to a 100-year storm event. This included the area known as the
floodway and the flood fringe which is farther from the main channel. This definition was aimed at
defining land for development purposes and in engineering assessment. (See diagram)
Figure 1: Floodplain defined (http://dnr.wi.gov/org/water/wm/dsfm/flood/standards.htm)
The floodplain is broader in its activities and functions than just the area of land that may be covered in
water during a possible 100-year flood event, and has been outlined more clearly in the paper by Junk et
al as, areas that are periodically inundated by the lateral overflow of rivers or lakes, and/or by direct
precipitation or groundwater (Junk, 111). Floodplains have also been called the aquatic/terrestrial
transition zone (ATTZ), which is the area that alternates between aquatic and terrestrial environments
(Junk, 111). They are also sometimes described interchangeably with the riparian zone (insert hyperlink).
However for this paper the term floodplain will be used while continuing to examine the more complete
picture contained in the aquatic/terrestrial transition zone. The spatial mosaic of floodplain habitats
changes over time due primarily to processes of flooding, channel avulsion, and cut-and-fill alluviation
resulting in dynamic patterns and rates of surface-hyporheic and groundwater exchange including
associated biogeochemical processes (Tockner, Lorang and Stanford 78)
The actual area of a floodplain in a given river may be possible to define, however it is a dynamic
changing system that can be aquatic, terrestrial, or a combination. The environmental change from the
aquatic to the terrestrial phase at a specific point in a floodplain may be as severe as the change from a
lake to a desert (Junk, 113). This change occurs temporally and spatially like most of the other attributes
of a river. The inshore edge of the aquatic environment that traverses the (floodplain) is the ‘moving
littoral’ (Junk, 111). The littoral zone (link to littoral zone) is the area submerged in water that lies
between the main river channel’s limnetic zone and the adjacent floodplain. In the following figure the
floodplain is adjacent to the littoral zone where the terrestrial plants lie.
Figure 2: Littoral Zone between the Floodplain and Limnetic Zone. (http://tinyurl.com/7m6vgg8)
Objectives
The objectives of this Stream and Watershed Restoration Wiki are to impart knowledge of this
developing and complex area of study, and to form a venue where information can be gathered and
exchanged between those that are interested in River Restoration. Rivers are complex freshwater
ecosystems with many distinct features as well as interrelated components. These components change
spatially and temporally, which is also true of the information available through this Wiki. Each area will
be linked throughout this document and can be found within the Stream and Watershed Restoration
Wiki for further development of the many distinguishing aspects of the Earth’s rivers.
The objectives of this section are to clearly define the form, function and ecological purpose of a river’s
floodplain, to examine the changes that have occurred historically that have created a disconnection of
the floodplain from the main channel and the effects that have occurred, and to outline restoration
methods that can be implemented to restore the function and connectivity of the floodplain to the river.
Floodplains have many known beneficial uses and studies continue to quantify those benefits.
Anthropogenic changes to rivers have severely altered and in many cases completely disconnected
rivers from the adjacent historical floodplain. The impact of these changes and the loss of the floodplain
function and benefit must be assessed and quantified. The movement of water through ground and
surface systems, floodplains, wetlands and watersheds is perhaps the greatest indicator of the
interaction of natural processes in the environment. (Floodplain Natural Resources and Functions).
Restoration efforts to improve the quality of the floodplain and its connection to the river should be a
priority in many river restoration efforts. Analysis and discussion of these efforts will be defined.
Floodplain Functions
There are many functions that a floodplain provides. The first and most obvious is flood wave
attenuation. A flood wave is the rise and fall of the water level in a river due to a storm or sudden snow
melt. A functioning floodplain will receive the water as it rises and attenuates this wave by taking the
energy from the wave laterally. Rivers without the function of flood wave attenuation will carry the
energy from the wave further downstream, which impacts the aquatic life in the channel. The floodplain
provides storage of water during a flood as well as conveyance. It reduces flow velocities and peaks and
also distributes sedimentation more evenly. Floodplains store this water for use during dry periods. One
acre of floodplain land flooded one foot deep holds 330,000 gallons of water (Floodplain Natural
Resources and Functions).
Because an incised channel can contain larger peak flows and often cannot dissipate flow energy across
the former floodplain, these channels are particularly dynamic.
Flood plains of the world deserve increased attention for their inherent biodiversity, natural water
cleansing and storage capacities, rejuvenation of productive soils, and role in maintaining fisheries,
among other goods and services provided to human societies, and for their aesthetic and cultural appeal
(Tockner, Lorang and Stanford 78).
Habitat Diversity
Floodplains also provide a rich ecosystem and are part of a total functioning system with the local
environment, and provide habitat that is not available elsewhere. Flluvial processes of cut-and-fill
alluviation create new channels, bars, and benches within a flood plain that in turn provides new surface
for subsequent vegetative recruitment and growth resulting in a shifting mosaic of interconnected
aquatic and terrestrial habitat patches (Tockner, Lorang and Stanford 76). Fish yields and production are
strongly related to the extent of accessible floodplain, whereas the main river is used as a migration
route by most of the fishes (Junk, 110). A functioning floodplain maintains biodiversity, provides
breeding and feeding grounds for a variety of species, and enhances the integrity of the ecosystem.
Many of the organisms colonizing floodplains have developed adaptations that enable them to survive
during an adverse period of drought or flood and even benefit from it (Junk, 113).
Fluvial dependent species inhabit a variety of aquatic habitats, but require lotic conditions at some point
during their life history stages (Kingsolving and Bain 1993, Galat et al. 2005; (Barko, Herzog and
O'Connell 247).
Floodplains have been reported to be used by fishes for feeding (O’Connell 2003), spawning (Killgore
and Baker 1996), rearing habitat (Turner et al. 1994), migration corridors (Sommer et al. 2004), and
refugia (Guillory 1979, Adams et al. 1999).
Semi-aquatic biota is specifically adapted to follow the transition zone between aquatic and terrestrial
habitats as flow varies and many require both habitats to complete their life cycle (Tockner, Lorang and
Stanford 78).
The shifting habitat mosaic concept (SHM) recognizes that the interaction of physical and biotic
processes in a flood plain produces a continually changing spatial pattern of habitats fostering high
biodiversity (Arscott et al., 2002; Van der Nat et al., 2003; Hauer and Lorange, 2004; Hohensinner et al.,
2004; Lorang et al., 2005; Stanford et al., 2005;Tockner, Lorang and Stanford 77).
Water Quality
Floodplains are also an important factor in improving the quality of water that enters a river after a
storm. The floodplain filters impurities from runoff, processes and distributes organic wastes, and also
moderates the temperature of the water.
Nutrient Transfer
The transfer of materials from the floodplain to the river as well as the river to the floodplain have been
studied and quantified as to its importance. Materials are transported from the river to the floodplain
(e.g. suspended sediments and nutrients) as well as from the floodplain to the river (e.g. organic detritus
and algal biomass) (Tockner et al., 522). Functioning and connected floodplains have an important
transfer to and from the river. This transfer is necessary for the development of sustainability of many
biological processes. Floodplains are distinct because they do not depend on upstream processing
inefficiencies of organic matter, although their nutrient pool is influenced by periodic lateral exchange of
water and sediments with the main channel (Junk, 110).
Flooding causes a perceptible impact on biota and that biota displays a defined reaction to flooding
(Junk, 110).
Wet-dry cycles affect all aspects of carbon and nutrient turnover, including mineralization, microbial
growth, greenhouse gas losses and denitrification (Tockner, Lorang and Stanford 80).
The flood plain is a complex mosaic of habitat patches, each slightly differing in productivity, standing
biomass, soil organic content and capacity to transform organic matter (Brunke and Gonser, 1997;
Robertson et al., 1999; Vallett et al., 2005; Tockner, Lorang and Stanford 79).
For at least a portion of the year, however, the floodplain becomes an important part of the aquatic
system food web as fishes migrate into these habitats and use the vast invertebrate food resource (Junk
et al. 1989).
Floodplain vegetation helps define and stabilize habitats over an area greater than the river channel
width, and its primary production in the form of litterfall ultimately fuels food webs in both the
floodplain and river channel (e.g., Wallace et al. 1987, Cuffney 1988, Wainright et al. 1992, Carlough
1994; Benke 235).
Floodplain Connection
The services provided by floodplains are inexorably linked to the frequency, seasonality and duration of
surface flooding and of groundwater and channel water levels, and the management of these
hydrological processes (Rouquette et al. 1580). Functioning floodplains go through a process of three
phases. These phases are outlined in the paper “Hydrological connectivity, and the exchange of organic
matter and nutrients in a dynamic river-floodplain system (Danube, Austria)”. Each of these phases has
its own function and benefit to the environment and the river. Shifts in the strength and type of
hydrological connectivity have major implications for structural and functional attributes of riverine
floodplains (Tockner et al., 530).
The first phase which occurs during the majority of the time is floodplain disconnection from the river.
Some lakes and swamps are isolated from the main channel for many months or even years. (Junk, 113)
Nutrient levels and primary productivity are low in the floodplain (Tockner et al., 530).
Autogenic processes dominating (e.g. sedimentation of autochthonous material, nutrient uptake and
grazing) as the ‘biotic interaction phase’ (Tockner et al., 530).
Phase II of floodplain connection is the seepage inflow phase. With only a subsurface connection
upstream, the floodplain contributes already considerable amounts of algal biomass and DOC to the
main river during phase II. (Tockner et al., 531)
With increasing water levels, the floodplain shifts from a closed to a more open system fed by nutrientrich ground water (Tockner et al., 530).
Define phase II as the ‘primary production phase’ (Tockner et al., 532).
The third floodplain connection phase is the upstream surface connection this is also thought of as the
‘transport phase’. The floodplain shifts from an autotrophic system during phase II to a heterotrophic
system during/after flooding (Tockner et al., 532).
The timing of flooding and the period since the last flood are essential in explaining transport patterns
(Tockner, 532).
Causes for Floodplain Disconnection
Today, flood plains are among the most endangered ecosystems worldwide because most have been
permanently inundated by reservoirs, which also limit or eliminate geomorphic forming flows, or are
disconnected by dikes and armoured by bank stabilization structures (Tockner, Lorang and Stanford 78).
Many changes have been made to rivers, especially in urban areas, that have affected the connection of
floodplains and disrupted the natural phases that would normally occur in a functioning floodplain. The
vast majority of human alteration to a free flowing river result in the control or dampening of flood
flows, extraction of water, disruption of the sediment supply and stabilization of river banks. Each
greatly reduces the dynamic physical drivers of floodplain dynamics, and thereby, directly impact
biophysical processes that are essential for sustaining river ecosystem integrity (Tockner, Lorang and
Stanford 83). Anthropogenic changes to the land uses along rivers, as well as the many methods
employed to alter and manage the flows associated with these rivers, have created a disconnect
between the river and its floodplain. Most large rivers in the temperate zone have been greatly
impacted by the construction of hydropower plants, regulation work for navigation purposes, land
reclamation projects and large-scale flood control measures (e.g. Dynesius & Nilsson, 1994). One of the
greatest influences that humans have had on the environment is the simplification of habitats,
landscapes, and catchments (Tockner, Lorang and Stanford 79).
Human impacts such as dams and levees have caused the truncation of flood pulses to floodplains.
Most riverine ecosystems are impacted by multiple human stressors including urbanization, flow
regulation, species invasion, mining and sediment truncation (Tockner, Lorang and Stanford 80).
Dams (connect to dam wiki) for flood control, water storage, and occasionally hydropower have had a
significant impact on floodplain biology. Dams and the reservoirs that are created as a result of dams
artificially control the flow of the river, reduce flooding, and drastically alter sedimentation pathways.
Levees have been put into place along many reaches of rivers as a way of controlling flooding. This
disconnects the river from the floodplain, and eradicates an entire system that had previously been in
place. Along the Middle Rio Grande (New Mexico, USA), impoundment and levee construction have
created riparian forests that differ in their inter-flood intervals (IFIs) because some floodplains are still
regularly inundated by the flood pulse (i.e., connected), while other floodplains remain isolated from
flooding (i.e., disconnected) (Valett et al. 220).
Water diversions from rivers for agricultural and human uses changes the amount of water available in a
river and that change is carried downstream. The water that is withdrawn from the river from these
diversions and withdrawals can significantly decrease the amount of flow in the river as compared to
historical flow. The San Juan-Chama project in New Mexico is an example of a water diversion that adds
flow to a reach of a river that would not normally be there while detracting from another system. Water
diversions from a river by diverting flow from one area to another or withdrawing the water for
consumption has an impact on the river system and decreases the connectivity to the floodplain by
making floodplain inundation less likely.
Rivers have been increasingly channelized as a way of controlling flooding. Channelization keeps the
flow within the main river channel and reduces the amount of flow that can cross into the floodplain.
In the past century, flow regulation has reduced or eliminated hydrological and ecological interactions
between many rivers and their floodplains (Valett et al. 220).
Water withdrawals
Groundwater pumping
It has been estimated that up to 90% of floodplains in Europe and North America have been “cultivated”
and hydrologically modified for agriculture (Tockner and Stanford 2002).
Effects from Loss of Connectivity
As suggested by Gutreuter et al. (1999) and Sommer et al. (2004), increasing river floodplain
connectivity may be an effective approach for reducing the impacts of non-native fishes and maintaining
biodiversity (Barko, Herzog and O'Connell 255).
Measuring and predicting consequences of changing landscapes, or in our case, riverscapes, is the
fundamental problem in contemporary ecology (Tockner, Lorang and Stanford 76).
Maintaining the connection between the river channel and floodplain is vital for diverse and productive
invertebrate assemblages and the higher trophic levels that depend on them (Benke 237).
Disturbances such as floods and droughts may affect genetic and species diversity (Tockner, Lorang and
Stanford 83).
Flood-plains have been drained, deforested, and often converted to agriculture (Benke 236).
Flood Pulse Concept
In recent years, ecologists have recognized that the phenomenon of a flooding river often represents a
beneficial ecological connection between the river and its semiaquatic floodplain, rather than an
unpredictable catastrophic disturbance (eg., Junk et al., 1989; Benke 225).
The principal driving force responsible for the existence, productivity, and interactions of the major
biota in river-floodplain systems is the flood pulse (Junk, 110).
The flood pulse concept (FPC) emphasizes the pulsing of river discharge as the major driving force that
determines the degree of connectivity, the exchange of matter and the processing of organic matter and
nutrients across river-floodplain gradients (Junk et al., 1989; Tockner et al., 2000; Junk and Wantzen,
2004; Thorp et al., 2006; Tockner, Lorang and Stanford 77).
The flood pulse concept of Junk et al. (1989) and Bayley (1995) emphasizes that inundation of the
floodplain creates and maintains riparian forests as some of the most productive and diverse
ecosystems in the biosphere (Valett et al. 220).
In semiarid floodplains, water is scarce except during the flood pulse.
Floodplain meadows are characteristic ecosystems which are heavily influenced by spring and winter
flooding (Carbiener 1969; Vecrin et al. 263).
Further investigation into the influence of floodpulse timing on both native and non-native assemblages
in temperate rivers and understanding the life history of non-native fishes invading these rivers should
be high research and management priorities (Barko, Herzog and O'Connell 255).
i. Benefit of controlled flood pulse
ii. Differences from natural flood pulse
Restoration
Restoration of floodplains and reconnection to the river system is an important aspect to river
restoration. The function of floodplains cannot be ignored. A focus of river restoration is to restore a
more natural hydrograph with gradual changes in floodplain inundation and exchange processes
(Tockner et al., 533).
We need system models that quickly respond in well-documented ways to natural and cultural forcings
so that consequences of landscape change can be more effectively translated to management and policy
(Tockner, Lorang and Stanford 77).
The findings from our study provide much needed insight into fish-floodplain function in a temperate,
channelized river system and suggest that lateral connectivity of the main river channel to less degraded
reaches of its floodplain should become a management priority not only to maintain faunal biodiversity
but also potentially reduce the impacts of non-native species in large river systems (Barko, Herzog and
O'Connell 244). Data collection was performed during the 1993 flood in the unimpounded reach of the
upper Mississippi River. This 500 year flood event provided a unique opportunity to investigate fish-
floodplain function because the main river channel is otherwise typically disjunct from approximately
82% of its floodplain by an extensive levee system (Barko, Herzog and O'Connell 244).
Case Studies
Ecosystem Services
A conversion of arable fields might result in even stronger constraints for restoration due to a possible
destruction of the meadow soil seed bank and modification of the soil chemical composition
(Manchester et al. 1998, Vecrin et al. 263).
Vecrin et al. (264) explain a preferred technique for reversion of arable land to semi-natural grasslands
in France. A commonly used technique is the sowing of meadow species, which is moderately expensive
and considered most feasible by many practitioners. This technique leads, at the same time, to (1) a fast
development of vegetation cover (Hutching & Booth 1996), (2) a reduction in soil erosion and (3) a
depletion of fertilizer residuals in the soil (Mitchley et al. 1996). The study examined the restoration
efforts to return a portion of an abandoned floodplain of the Meuse to produce high quality hay that is
native to the area, under a low-intensity management regime. Vecrin et al. (269) stated that the
vegetation development in the restored meadow over three years showed that the mean species
richness was significantly lower in the sown meadow than in the target communities and the floristic
compositions were different. However, the similarity between restored and target meadows increased
significantly with time, which suggests that the restoration of the sown meadow will proceed in the
direction of the target meadow.
Many studies showed that a combination of a high productivity and an absence of viable propagules of
characteristic species are serious bottlenecks in the restoration process (Bakker et al. 1996; Verhagen et
al. 2001; Vecrin et al. 263).
Priorities for the management of lowland rural floodplains in many parts of Europe have changed from a
focus on agricultural production towards multi-functional landscapes that provide a range of
environmental, social and economic benefits to society (Rouquette et al. 1566).
A key challenge for the management of floodplains, and for sustainable natural resource management in
general, is to examine the ecosystem services provided by alternative land-use types and to explore
ways in which different management priorities can be integrated more effectively (Rouquette et al.
1567).
Environmental Flows (link to Ryan M's Wiki)
An innovative approach to assess floodplain habitats is to calculate their ‘water age’, or the length of
time that a parcel of water is contained in a particular habitat (Baranyi et al., 2002; Hein et al., 2004;
Tockner, Lorang and Stanford 82).
Hydrology plays a key role in determining the land use and habitat types that occur on lowland
floodplains. Vegetation responds to the depth of the water table, the quality of the drainage and to the
depth, duration and seasonality of flooding (Runhaar et al. 1997, Silvertown et al. 1999, Wheeler et
al.2004; Rouquette 1578).
Hydrological regimes are defined in terms of mean water-table depth, days with surface water and
fluvial flood probability, and are based on expert knowledge and published sources (Wheeler et al. 2004,
Barsoum et al. 2005; Rouquette 1569).
Several recent reviews have emphasized the importance of reestablishing natural flow regimes, rather
than just minimum flows, in regulated systems (e.g., Poff et al. 1997, Sparks et al. 1998, Galat et al.
1998, Molles et al. 1998, Toth et al. 1998).
Researchers have for some time recognized that a basic understanding of how hydrologic regimes
influence the ecophysiological processes of plant species endemic to bottomland hardwood ecosystems
is fundamental to developing future restoration and management strategies for these systems
(Lockhart, Gardiner and Leininger 152).
Future Restoration for the Middle Rio Grande Flood Plain
Conclusion
Not only are natural flood plains among the most biologically complex and diverse landscapes on Earth,
but they also contribute more than 25% of all terrestrial ecosystem services although they cover only
1.4% of the land surface area (Tockner and Stanford, 2002; Tockner, Lorang and Stanford 83).
They are now among the most threatened landscapes worldwide with 47% of all animals federally
endangered in the U.S. being freshwater species that occupy flood plains (Tockner and Stanford, 2002;
Tockner, Lorang and Stanford 83).
Floodplains have a specific design and use as it pertains to the environment. It is part of an integrated
system. Surface water, ground water, floodplains, wetlands and other features do not function as
separate and isolated components of the watershed, but rather as a single, integrated natural system
(Floodplain Natural Resources and Functions). Removal or alteration of a single process has
ramifications throughout the system as a whole. Floodplain connection and interaction must continue to
be prioritized in river restoration.
Clearly, the relative contributions of habitats and natural inundation regime must be assessed in any
river-floodplain ecosystem to understand its natural functioning (Benke 234)
Years ago Poff and Ward (1989) and later Barinaga (1996) and Stanford et al. (1996) argued that
restoration of riverine heterogeneity could only occur by naturalizing flows and sediment loading,
removing lateral levees and other constraints, allowing the river to do the work of restoration (Tockner,
Lorang and Stanford 80).
Timing, intensity, duration and frequency of flood pulses strongly influence what processes will be
activated and at what rates they will proceed within the flood plain habitat complex (Tockner, Lorang
and Stanford 80).
Instead of a forested swamp, vegetation in many tropical floodplains consists of small aquatic and
semiaquatic plants (e.g., Hamilton et al. 1996, Junk and Piedade 1997; Benke 235).
Regardless of regional characteristics, however, flood regimes play a vital role in defining aquatic
habitats for fauna (Benke 235).
Benke (235) stated in his study that at the system level, invertebrate biomass was highest in the
floodplain because of its large surface area, a similar finding to Smock et al. (1992) in their Virginia
streams.
References
Barko, Valerie A, David P Herzog and Martin T O'Connell. "Responses of Fishes to Floodplain
Connectivity During and Following a 500-year Flood Event in the Unimpounded Upper
Mississippi River." WETLANDS 26.1 (2006): 244-257. Web. 30 January 2012.
Benke, Arthur C. "Importance of Flood Regime to Invertebrate Habitat in an Unregulated RiverFloodplain Ecosystem." Journal of the North American Benthological Society 20.2 (2001): 225240. Web. 28 2 2012. <www.jstor.org/stable/1468318>.
Birken, Adam S and David J Cooper. "Processes of Tamarix Invasion and Floodplain Development along
the Lower Green River, Utah." Ecological Applications 16.3 (2006): 1103-1120. Web. 30 January
2012.
"Floodplain Natural Resources and Functions." Training. n.d. Web. 28 February 2012.
<http://training.fema.gov/EMIWeb/edu/docs/fmc/Chapter%208%20%20Floodplain%20Natural%20Resources%20and%20Functions.pdf>.
Gorski, Konrad, et al. "Fish recruitment in a large, temperate floodplain: the importance of annual
flooding, temperature and habitat complexity." Freshwater Biology 56 (2011): 2210-2225. Web.
30 January 2012.
Ickes, Brian S, et al. River floodplain connectivity and lateral fish passage: A literature review. Contract
Completion. La Crosse: U.S. Geological Survey, Upper Midwest Environmental Sciences Center,
2005. Web. 30 January 2012.
Junk, Wolfgang J, P B Bayley and R E Sparks. "The Flood Pulse Concept in River-Floodplain Systems."
Proceedings of the Internation Large River Symposium 106 (1989): 110-127. Document.
Lockhart, Brian R, et al. "Flooding Facility Helps Scientists Examine the Ecophysiology of Floodplain
Species Use in Bottomland Hardwood Restorations." Ecological Restoration 24.3 (2006): 151157. Web. 28 2 2012.
Noe, Gregory B and Cliff R Hupp. "Carbon, Nitrogen, and Phosphorus Accumulation in Floodplains of
Atlantic Coastal Plain Rivers, USA." Ecological Applications 15.4 (2005): 1178-1190. Web. 30
January 2012.
Rouquette, J R, et al. "Synergies and trade-offs in the management of lowland rural floodplains: an
ecosystem services approach." Hydrological Sciences Journal 56.8 (2011): 1566-1581. Web. 30
January 2012.
State of the Environment Report: Emerging issue - Loss of floodplain connectivity. Governmental.
Western Australia: Environmental Protection Authority, 2007. Web. 28 February 2012.
<http://www.soe.wa.gov.au/report/inland-waters/emerging-issue-loss-of-floodplainconnectivity.html>.
Stromber, J C. "Seasonal reversals of upland-riparian diversity gradients in the Sonoran Desert." Diversity
and Distributions 13 (2007): 70-83. Web. 30 January 2012.
Tockner, Klement, et al. "Hydrological connectivity, and the exchange of organic matter and nutrients in
a dynamic river-floodplain system (Danube, Austria)." Freshwater Biology 41 (1999): 521-535.
Document.
Tockner, Klement, Mark S Lorang and Jack A Stanford. "River Flood Plains are Model Ecosystems to Test
General Hyrogeomorphic and Ecological Concepts." River Research and Applications 26.1 (2010):
76-86. Web. 29 2 2012.
Valett, H M, et al. "Biogeochemical and Metabolic Responses to the Flood Pulse in a Semiarid
Floodplain." Ecology 86.1 (2005): 220-234. Web. 30 January 2012.
Vecrin, M P, et al. "Restoration of Species-Rich Flood-Plain Meadows from Abandoned Arable Fields in
NE France." Applied Vegetation Science 5.2 (2002): 263-270. Web. 28 2 2012.
<www.jstor.org/stable/1479074>.