FLOOD PULSE DYNAMICS OF AN UNREGULATED RIVER FLOODPLAIN IN THE SOUTHEASTERN U.S. COASTAL PLAIN

Ecology ◽  
2000 ◽  
Vol 81 (10) ◽  
pp. 2730-2741 ◽  
Author(s):  
Arthur C. Benke ◽  
Indrajeet Chaubey ◽  
G. Milton Ward ◽  
E. Lloyd Dunn
2020 ◽  
Vol 25 (1) ◽  
pp. 69-75 ◽  
Author(s):  
Christopher P. Bonvillain ◽  
Quenton C. Fontenot

Abstract Anthropogenic modifications to river-floodplain systems can decouple floodplains from mainstem inputs, alter flood pulse dynamics, and disrupt population dynamics and trophic web stability of aquatic biota. The Atchafalaya River Basin (ARB) receives an annual flood pulse from the Mississippi River that contributes to high crayfish abundance. Conversely, reduced crayfish abundance in the Barataria Basin (BB) is attributed to the system no longer receiving an annual flood pulse from the Mississippi River. Therefore, the purpose of this research was to determine if the absence of an annual flood pulse and reduced crayfish abundance influenced the diets of carnivorous fishes by examining stomach contents of fishes from both basins. Stomach contents were grouped as crayfish, fish, non-crayfish invertebrate, and herpetological. Although the percent occurrence of crayfish in fish stomachs differed between floodplain inundation and low-water periods in the ARB, crayfish were still the major diet constituent of ARB fishes during both periods. Non-crayfish invertebrate was the major diet constituent in BB fishes, with crayfish ranking as the second fewest diet constituent present. Our results demonstrate how flood pulse dynamics influence crayfish, and ultimately trophic webs, in large river-floodplain systems.


2016 ◽  
Vol 201 ◽  
pp. 129-136 ◽  
Author(s):  
Whaldener Endo ◽  
Carlos A. Peres ◽  
Torbjørn Haugaasen
Keyword(s):  

Water ◽  
2021 ◽  
Vol 13 (21) ◽  
pp. 3034
Author(s):  
Dirk Thielen ◽  
Paolo Ramoni-Perazzi ◽  
Mary L. Puche ◽  
Marco Márquez ◽  
José Isrrael Quintero ◽  
...  

The Pantanal is the largest wetland of the world and one of the most important biodiversity hotspots in South America. An unprecedented ongoing megadrought is severely affecting its ecological functioning, flood pulse dynamics, and fire regime. Regarding this problematic, the present study generates reliable information about the following key issues: 1—Evolution and dynamics, 2—Origin and determinants, and 3—Forecast based on identified determinants and current trends. Results show that the evolution of the megadrought has been differentiable in both, space and time. As for its origin and determinants, Climate Change was ratified as one of the most important threats to the Pantanal, and to vast areas of South America, since a strong correlation was identified between megadrought’s dynamics and the occurrence of intense marine heatwaves at Northern Hemisphere oceanic waters, and more specifically, at the Northeast Pacific. Results also show that the megadrought is expected to continue at both the Pantanal and the surrounding Highlands, at least until December 2023. Thus, an intensification of fires risk, extending now to areas historically flooded or perhumid should be expected, concomitantly to a very negative impact on non-fire-resistant vegetation cover, as well as ecosystem functioning and biodiversity, perhaps even worse than those from 2020, widely covered by the international media.


2016 ◽  
Vol 44 (2) ◽  
pp. 293-304 ◽  
Author(s):  
Rafael Hernandez Guzman ◽  
Arturo Ruiz Luna ◽  
Cesar A. Berlanga Robles ◽  
Jesus T. Ponce Palafox

2009 ◽  
Vol 69 (2 suppl) ◽  
pp. 517-527 ◽  
Author(s):  
GM. Pauleto ◽  
LFM. Velho ◽  
PRB. Buosi ◽  
AFS. Brão ◽  
FA. Lansac-Tôha ◽  
...  

Spatial and temporal patterns of plankton ciliates species composition in the Paraná River floodplain were investigated. Samplings were carried out in twelve environments in two distinct hydrological periods (limnophase and potamophase). A total of 61 species of ciliates were recorded, and among them 21 are classified as pelagic while 40 are considered preferentially as littoral species. The registered species belong to eleven orders, and among them, Prostomatida was the most specious followed by Hymenostomatida and Peritrichida. The ciliate species composition was significantly distinct between periods, but not among environments. In this way, typically pelagic species characterized the ciliate community during the limnophase period, while the littoral species were predominant during the potamophase period. Our results strongly support the idea of the flood pulse as the main factor driving the composition pattern of the planktonic ciliates community in the Paraná River floodplain.


2019 ◽  
Author(s):  
Jaques Everton Zanon

AbstractThe flood pulse concept refers to seasonal variations in river water level and is the driving force in river-floodplain systems that ‘responsible for the existence, productivity and interactions’ of these system’s biota. This seasonal variation is inherent to river-floodplain systems and establishes a natural pattern of these ecosystems that has frequently been observed in nature. One particular river-floodplain system of interest is the Upper Parana River and its floodplain, whose upstream contains a reservoir cascade that caused profound alterations on its flooding regime by having diminished flood magnitude, but increased its frequency. In this study, I sought to explore the flood pulse condition in the Upper Paraná River Floodplain by using a set of state-of-the-art spectral and non-linear analyses and a time series of water level fluctuations (1968-2017) from this system. I divided the data into four periods: i) natural regime period, ii) transitional period, iii) dam cascade period, and iv) Primavera’s dam period. Spectral analysis demonstrated a decrease in the annual cycle amplitude, reflected in its power spectrum, which means a weakening in the difference between flood and drought events. Additionally, nonlinear dynamical analysis revealed a less deterministic and predicable behavior leading to more erratic fluctuations jeopardizing the temporal heterogeneity of that system.


2015 ◽  
Vol 2 (11) ◽  
pp. 150299 ◽  
Author(s):  
Leandro Castello ◽  
Victoria J. Isaac ◽  
Ram Thapa

Seasonally fluctuating water levels, known as ‘flood pulses’, control the productivity of large river fisheries, but the extent and mechanisms through which flood pulses affect fishery yields are poorly understood. To quantify and better understand flood pulse effects on fishery yields, this study applied regression techniques to a hydrological and fishery record (years 1993–2004) for 42 species of the Amazon River floodplains. Models based on indices of fishing effort, high waters and low waters explained most of the interannual variability in yields ( R 2 =0.8). The results indicated that high and low waters in any given year affected fishery yields two and three years later through changes in fish biomass available for harvesting, contributing 18% of the explained variability in yields. Fishing effort appeared to amplify high and low water effects by changing in direct proportion to changes in fish biomass available for harvesting, contributing 62% of the explained variability in yields. Although high waters are generally expected to have greater relative influence on fishery yields than low waters, high and low waters exerted equal forcing on these Amazonian river-floodplain fishery yields. These findings highlight the complex dynamics of river-floodplain fisheries in relation to interannual variability in flood pulses.


2012 ◽  
Vol 97 (1) ◽  
pp. 41-54 ◽  
Author(s):  
Károly Schöll ◽  
Anita Kiss ◽  
Mária Dinka ◽  
Árpád Berczik
Keyword(s):  

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