The influence of flood pulse on fish communities of floodplain canals in the Middle Solimões River, Brazil

The functioning of large river systems with adjacent floodplains is strongly influenced by the flood pulse. This phenomenon is the main structuring force for the biota, including fish communities that use floodplain environments for spawning, feeding, nursery and refuge. In floodplains and in the entire basin, the volume of water controls internal flows. During rising water, the high discharge of the river acts as a natural barrier to the canals that connect floodplain lakes and the Solimões River, because the water flows from river to lake. During the dry period, there is a reduction of discharge and the water flow is reversed or stationary. These canals are environments with distinct ecological characteristics such as differentiated limnology and water level variation intensely affected by the hydrological cycle. Therefore, we surveyed the influence of the flood pulse on fish communities that inhabit two canals that connect floodplain lakes to the Middle Solimões River. Particularly, we evaluated the hypothesis that the Solimões River flow direction is not perfectly parallel to its banks, which creates peripheral flows that direct water from the rivers to the floodplain lake canals. Our analysis indicated that the seasonal pattern is stronger than the spatial. Beside this, we observed that the positions of the canals in relation to the main river flow somehow affect the fish assemblages. Finally, we conclude that the flood pulse is the main structuring force acting on these fish communities.

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Fish diversity of floodplain lakes on the lower stretch of the Solimões River

Brazilian Journal of Biology ◽

10.1590/s1519-69842004000300013 ◽

2004 ◽

Vol 64 (3a) ◽

pp. 501-510 ◽

Cited By ~ 17

Author(s):

F. K. Siqueira-Souza ◽

C. E. C. Freitas

Keyword(s):

Species Richness ◽

Fish Community ◽

River Flow ◽

Abundant Species ◽

Floodplain Lakes ◽

Fish Diversity ◽

The Town ◽

Solimões River

The fish community of the Solimões floodplain lakes was studied by bimonthly samples taken from May 2001 to April 2002. These were carried out at lakes Maracá (03º51'33"S, 62º35'08,6"W), Samaúma (03º50'42,1"S, 61º39'49,3"W), and Sumaúma and Sacambú (03º17'11,6"S and 60º04'31,4"W), located between the town of Coari and the confluence of the Solimões and Negro rivers. Collections were done with 15 gillnets of standardized dimensions with several mesh sizes. We collected 1,313 animals distributed in 77 species, belonging to 55 genera of 20 families and 5 orders. Characiformes was the most abundant Order, with a larger number of representatives in the Serrasalmidae and Curimatidae. The most abundant species in the samplings were Psectrogaster rutiloides (132 individuals), Pigocentrus nattereri (115 individuals), and Serrasalmus elongatus (109 individuals). Lakes Samaúma, Sacambú, and Sumaúma were adjusted to logarithmic and lognormal series. The diversity exhibited an inverse gradient to the river flow, showing the highest diversity at Lake Sumaúma, followed by Samaúma, Sacambú, and Maracá. Species richness estimated through the jackknife technique ranged from 78 to 107 species.

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Intra- and inter-annual changes in the condition factors of three Curimatidae detritivores from Amazonian floodplain lakes

Biota Neotropica ◽

10.1590/1676-0611-bn-2014-0001 ◽

2015 ◽

Vol 15 (4) ◽

Cited By ~ 1

Author(s):

Gisele Batista Correia ◽

Flávia Kelly Siqueira-Souza ◽

Carlos Edwar de Carvalho Freitas

Keyword(s):

Amazon Basin ◽

Hydrological Cycle ◽

Global Climate ◽

High Water ◽

Flood Pulse ◽

Floodplain Lakes ◽

Key Factor ◽

Length Data ◽

Dry Seasons ◽

Annual Changes

The flood pulse is a key factor that drives the biota of large rivers with adjacent floodplains, but the direction and intensity of its effects are not uniform for all trophic guilds of fish. In this study, we tested the existence of intra- and inter-annual changes in the relative condition factors (kn) of three Curimatidae: Potamorhina altamazonica, Potamorhina latior, and Psectrogaster rutiloides. We used weight and length data from fish that were caught in eight floodplain lakes of the Rio Solimões. These data were from experimental fisheries during each season of the hydrological cycle: flooding, flood, drying, and dry from 2004, 2005, and 2006. In general, there are similar patterns of intra-annual changes for these three species, with the highest estimates of kn during high water conditions. The lowest values were observed during the drying and dry seasons of 2005, when an extreme drought occurred in the Amazon basin. Higher values were observed during the same seasons in the year post-drought. We hypothesized that these patterns would be explained by the biological characteristics of these species and the effects of intra-annual hydrological changes, mainly the flood pulse effect, and by inter-annual climatic events, which are determined by global climate phenomena.

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The Effect of Hydrological Connectivity on the Zooplankton Structure in Floodplain Lakes of a Regulated Large River (the Lower Vistula, Poland)

Water ◽

10.3390/w11091924 ◽

2019 ◽

Vol 11 (9) ◽

pp. 1924 ◽

Cited By ~ 2

Author(s):

Napiórkowski ◽

Bąkowska ◽

Mrozińska ◽

Szymańska ◽

Kolarova ◽

...

Keyword(s):

Diversity Index ◽

Zooplankton Community ◽

Flood Pulse ◽

Large River ◽

Intermediate Disturbance Hypothesis ◽

Floodplain Lakes ◽

Zooplankton Community Structure ◽

Growing Seasons ◽

Vistula River ◽

Α Diversity

The zooplankton community structure and diversity were analysed against the gradient of floodplain lakes connectivity and water level under different flood-pulse dynamics in the Vistula River. The lakes differed in terms of hydrology, among others in the degree/type of their connection with the river (permanent, temporary and no connection). The study was conducted during the growing seasons in the years 2006–2013 and involved the lower Vistula River and three floodplain lakes: isolated, transitional and connected. Water samples were collected biweekly from April to September. Zooplankton was the most diverse and abundant in the transitional lake (the highest Shannon α-diversity index H’ and Pielou’s evenness index J’). The gentle washing of the lakes might have stimulated the development of zooplankton in accordance with the Intermediate Disturbance Hypothesis. The diversity and density of zooplankton were higher in the connected lake compared to the isolated one. We confirmed the hypothesis that zooplankton should be more abundant and diverse in floodplain lakes connected with the river (or transitional) than in isolated ones. Zooplankton analyses indicated that hydrological conditions (flood-pulse regime) contributed most substantially to zooplankton diversity and density in the floodplain lakes of the lower Vistula valley.

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Historical Changes in Large River Fish Assemblages of the Americas

Historical Changes in Large River Fish Assemblages of the Americas ◽

10.47886/9781888569728.ch3 ◽

2005 ◽

Keyword(s):

Fish Assemblages ◽

Age Groups ◽

Fish Fauna ◽

Flood Pulse ◽

Large River ◽

Commercial Fishing ◽

Pulp Mills ◽

Hydroelectric Project ◽

Great Slave Lake ◽

River Fish

Abstract.—The Slave River is the largest tributary to Great Slave Lake and the second largest river flowing northward in North America. There are no dams or major industrial developments on the lower Slave River, but further upstream in its Peace and Athabasca tributaries there are numerous pulp mills and a large hydroelectric project (Bennett Dam). These developments appear to have had limited effects on the Slave River fish fauna. The most significant concern is the reduced flood-pulse due to flow regulation, which is hypothesized to have affected spawning success in some species. The other major human impact is from commercial fishing on Great Slave Lake. Migratory species, such as inconnu, have been extirpated from some tributaries due to overfishing. In the Slave River, however, the impact of fishing on inconnu and other species appears to have been less severe. Although the number of age-groups has decreased within some species, the species composition appears to have remained stable. There is little evidence of species introductions into the system, but some rare species, such as chum salmon Oncorhynchus keta, may be extirpated.

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Influence of niche and neutral processes on fish communities associated with changes in macrophyte rafts along the hydrological cycle

Biologia ◽

10.1007/s11756-021-00747-4 ◽

2021 ◽

Author(s):

Lucena R. Virgilio ◽

Werther Pereira Ramalho ◽

João C. B. Silva ◽

Monik Oliveira da Suçuarana ◽

Rodrigo Souza Gomes ◽

...

Keyword(s):

Hydrological Cycle ◽

Fish Communities ◽

Neutral Processes

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Transformation of the Flow Regime of a Large Allochthonous River in Central Europe—An Example of the Vistula River in Poland

Water ◽

10.3390/w12020507 ◽

2020 ◽

Vol 12 (2) ◽

pp. 507 ◽

Cited By ~ 1

Author(s):

Dariusz Wrzesiński ◽

Leszek Sobkowiak

Keyword(s):

Flow Regime ◽

Annual Cycle ◽

River Flow ◽

Hydrological Cycle ◽

Temporal Structure ◽

Flow Characteristics ◽

Point Of View ◽

Theoretical Point ◽

Vistula River ◽

Basin Water

Identification of river flow regime and its possible changes caused by natural factors or human activity is one of major issues in modern hydrology. In such studies different approaches and different indicators can be used. The aim of this study is to determine changes in flow regime of the largest river in Poland—the Vistula, using new, more objectified coefficients and indices, based on data recorded in 22 gauges on the Vistula mainstream and 38 gauges on its tributaries in the multi-year period 1971–2010. The paper consists of three main parts: in the first part, in order to recognize changes in the flow regime characteristics along the Vistula, data from gauges located on the river mainstream were analyzed with the help of the theory of entropy. In the second part gauging stations on the Vistula mainstream and its tributaries were grouped; values of the newly introduced pentadic Pardé’s coefficient of flow (discharge) (PPC) were taken as the grouping criterion. In the third part of the study a novel method of determining river regime characteristics was applied: through the recognition of the temporal structure of hydrological phenomena and their changes in the annual cycle sequences of hydrological periods (characteristic phases of the hydrological cycle) on the Vistula River mainstream and its tributaries were identified and their occurrence in the yearly cycle was discussed. Based on the detected changes of the 73-pentad Pardé’s coefficients of flow four main types of rivers were distinguished. Transformation of the flow regime was reflected in the identified different sequences of hydrological periods in the average annual cycle. It was found that while transformation of the Vistula River regime occurred along its whole course, the most frequent changes were detected in its upper, mountainous reaches, under the influence of the flow characteristics of its tributaries. This allowed the Vistula to be considered the allochthonous river. These findings are interesting not only from a theoretical point of view, but they also can be valuable to stakeholders in the field of the Vistula River basin water management and hydrological forecasting, including flood protection, which has recently become a matter of growing concern due to the observed effects of climate change and human impact.

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