A classification of the major habitats of Amazonian black-water river floodplains and a comparison with their white-water counterparts

The boundary zone between two different hydrological regimes is often a biologically enriched environment with distinct planktonic communities. In the center of the Amazon River basin, muddy white water of the Amazon River meets with black water of the Negro River, creating a conspicuous visible boundary spanning over 10 km along the Amazon River. Here, we tested the hypothesis that the confluence boundary between the white and black water rivers concentrates prey and is used as a feeding habitat for juvenile fish by investigating the abundance, biomass and distribution of mesozooplankton and ichthyoplankton communities across the two rivers. Our results show that mesozooplankton abundance and biomass were higher in the black-water river compared to the white-water river; however an exceptionally high mesozooplankton abundance was not observed in the confluence boundary. Nonetheless we found the highest abundance of ichthyoplankton in the confluence boundary, being up to 9-fold higher than in adjacent rivers. The confluence boundary between black and white water rivers may function as a boundary layer that offers benefits of both high zooplankton prey concentrations (black-water) and low predation risk (white-water). This forms a plausible explanation for the high abundance of ichthyoplankton in the confluence zone of black and white water rivers.

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The abundance and biomass of mesozooplankton and ichthyoplankton in the confluence boundary of the Negro and the Amazon Rivers

10.7287/peerj.preprints.2769v1 ◽

2017 ◽

Author(s):

Ryota Nakajima ◽

Elvis V Rimachi ◽

Edinaldo N Santos-Silva ◽

Adi Khen ◽

Tetsuo Yamane ◽

...

Keyword(s):

Juvenile Fish ◽

Boundary Spanning ◽

Amazon River ◽

Black And White ◽

Black Water ◽

Negro River ◽

Feeding Habitat ◽

White Water ◽

Black Water River ◽

Planktonic Communities

The boundary zone between two different hydrological regimes is often a biologically enriched environment with distinct planktonic communities. In the center of the Amazon River basin, muddy white water of the Amazon River meets with black water of the Negro River, creating a conspicuous visible boundary spanning over 10 km along the Amazon River. Here, we tested the hypothesis that the confluence boundary between the white and black water rivers concentrates prey and is used as a feeding habitat for juvenile fish by investigating the abundance, biomass and distribution of mesozooplankton and ichthyoplankton communities across the two rivers. Our results show that mesozooplankton abundance and biomass were higher in the black-water river compared to the white-water river; however an exceptionally high mesozooplankton abundance was not observed in the confluence boundary. Nonetheless we found the highest abundance of ichthyoplankton in the confluence boundary, being up to 9-fold higher than in adjacent rivers. The confluence boundary between black and white water rivers may function as a boundary layer that offers benefits of both high zooplankton prey concentrations (black-water) and low predation risk (white-water). This forms a plausible explanation for the high abundance of ichthyoplankton in the confluence zone of black and white water rivers.

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Calcium fluxes in Hoplosternum littorale (tamoatá) exposed to different types of Amazonian waters

Neotropical Ichthyology ◽

10.1590/s1679-62252009005000002 ◽

2009 ◽

Vol 7 (3) ◽

pp. 465-470 ◽

Cited By ~ 3

Author(s):

Bernardo Baldisserotto ◽

Carlos Eduardo Copatti ◽

Levy Carvalho Gomes ◽

Edsandra Campos Chagas ◽

Richard Philip Brinn ◽

...

Keyword(s):

Organic Carbon ◽

Water Transfer ◽

Well Water ◽

Acidic Ph ◽

Clear Water ◽

Black Water ◽

Neutral Ph ◽

Different Types ◽

White Water ◽

Hoplosternum Littorale

Fishes that live in the Amazonian environment may be exposed to several kinds of waters: "black waters", containing high dissolved organic carbon and acidic pH, "white waters", with ten fold higher Ca2+ concentrations than black waters and neutral pH, and "clear waters", with two fold higher Ca2+ concentrations than black waters and also neutral pH. Therefore, the aim of the present study was to analyze Ca2+ fluxes in the facultative air-breather Hoplosternum littorale (tamoatá) exposed to different Amazonian waters. Fishes were acclimated in well water (similar to clear water) and later placed in individual chambers for Ca2+ fluxes measurements. After 4 h, water from the chambers was replaced by a different type of water. Transfer of tamoatás to ion-poor black or acidic black water resulted in net Ca2+ loss only in the first 2 h of experiment. However, transfer from black or acidic black water to white water led to only net Ca2+ influxes. The results obtained allowed us to conclude that transfer of tamoatás to ion-poor waters (black and acidic black water) led to transient net Ca2+ loss, while the amount of Ca2+ in the ion-rich white water seems adequate to prevent Ca2+ loss after transfer. Therefore, transfer of tamoatás between these Amazonian waters does not seem to result in serious Ca2+ disturbance.

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Composition and community structure of mangroves distributed on the east coast of Marajó Island, Brazil

10.21203/rs.3.rs-1196739/v1 ◽

2022 ◽

Author(s):

Barbara Luzia Santos de Oliveira Faro ◽

Priscila Sanjuan de Medeiros-Sarmento ◽

Norma Ely Santos Beltrão ◽

Paulo Weslem Portal Gomes ◽

Ana Cláudia Caldeira Tavares-Martins

Keyword(s):

Floristic Composition ◽

Distribution Patterns ◽

Major Influence ◽

Structural Development ◽

Black Water ◽

Composition And Structure ◽

Marine System ◽

Marajó Island ◽

White Water ◽

Degree Of Similarity

Abstract Mangroves in the Amazon are influenced by several environmental conditions that determine the composition and structural development of the arboreal flora, which results in different distribution patterns. In this study, we sought to answer two questions: (1) what is the composition and structure of the mangroves near the mouth of the Amazon River in Marajó Island? (2) Are the fringe and inland mangroves more similar or dissimilar in terms of floristic composition? For this, we delimited a fringe zone and an inland zone about 1 km apart from each other. In each zone, we distributed five 400-m2 plots. The individuals were grouped into diameter and height classes and structural and phytosociological parameters were calculated. Ten species were recorded in the mangroves, of which seven are typical of white-water (várzea) and black-water (igapó) flooded forest ecosystems. We believed the adjacent ecosystems and the hydrological network are inducing the establishment of such species. The composition and structure of mangroves did not differ statistically between zones, and the degree of similarity may be a result of similar environmental factors in these zones such as low relief and high frequency of macrotides. We conclude that the vegetation of the studied mangroves has a major influence of the fluvial-marine system of the great rivers of the Amazon associated with a diversity of ecosystems that, together, generate greater floristic richness when compared to mangroves in other regions.

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Wood growth patterns of Macrolobium acaciifolium (Benth.) Benth. (Fabaceae) in Amazonian black-water and white-water floodplain forests

Oecologia ◽

10.1007/s00442-005-0147-8 ◽

2005 ◽

Vol 145 (3) ◽

pp. 454-461 ◽

Cited By ~ 86

Author(s):

Jochen Schöngart ◽

Maria Teresa F. Piedade ◽

Florian Wittmann ◽

Wolfgang J. Junk ◽

Martin Worbes

Keyword(s):

Growth Patterns ◽

Floodplain Forests ◽

Black Water ◽

White Water

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Dissolved oxygen and its response to eutrophication in a tropical black water river

Journal of Environmental Management ◽

10.1016/j.jenvman.2010.03.009 ◽

2010 ◽

Vol 91 (8) ◽

pp. 1730-1737 ◽

Cited By ~ 22

Author(s):

Tim Rixen ◽

Antje Baum ◽

Harni Sepryani ◽

Thomas Pohlmann ◽

Christine Jose ◽

...

Keyword(s):

Dissolved Oxygen ◽

Black Water ◽

Black Water River

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The density and biomass of mesozooplankton and ichthyoplankton in the Negro and the Amazon Rivers during the rainy season: the ecological importance of the confluence boundary

PeerJ ◽

10.7717/peerj.3308 ◽

2017 ◽

Vol 5 ◽

pp. e3308 ◽

Cited By ~ 3

Author(s):

Ryota Nakajima ◽

Elvis V. Rimachi ◽

Edinaldo N. Santos-Silva ◽

Laura S.F. Calixto ◽

Rosseval G. Leite ◽

...

Keyword(s):

Rainy Season ◽

Fish Larvae ◽

Amazon River ◽

Black And White ◽

Black Water ◽

Negro River ◽

Feeding Habitat ◽

White Water ◽

Ecological Importance ◽

Density And Biomass

The boundary zone between two different hydrological regimes is often a biologically enriched environment with distinct planktonic communities. In the center of the Amazon River basin, muddy white water of the Amazon River meets with black water of the Negro River, creating a conspicuous visible boundary spanning over 10 km along the Amazon River. Here, we tested the hypothesis that the confluence boundary between the white and black water rivers concentrates prey and is used as a feeding habitat for consumers by investigating the density, biomass and distribution of mesozooplankton and ichthyoplankton communities across the two rivers during the rainy season. Our results show that mean mesozooplankton density (2,730 inds. m−3) and biomass (4.8 mg m−3) were higher in the black-water river compared to the white-water river (959 inds. m−3; 2.4 mg m−3); however an exceptionally high mesozooplankton density was not observed in the confluence boundary. Nonetheless we found the highest density of ichthyoplankton in the confluence boundary (9.7 inds. m−3), being up to 9-fold higher than in adjacent rivers. The confluence between white and black waters is sandwiched by both environments with low (white water) and high (black water) zooplankton concentrations and by both environments with low (white water) and high (black water) predation pressures for fish larvae, and may function as a boundary layer that offers benefits of both high prey concentrations and low predation risk. This forms a plausible explanation for the high density of ichthyoplankton in the confluence zone of black and white water rivers.

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Dynamic and Structure Profiling of Kampar River, Slim River and Sungkai River: White Water Recreation Rivers in the State of Perak, Malaysia

Turkish Journal of Computer and Mathematics Education (TURCOMAT) ◽

10.17762/turcomat.v12i3.747 ◽

2021 ◽

Vol 12 (3) ◽

pp. 428-431

Author(s):

Jaffry Zakaria Et.al

Keyword(s):

Geographical Location ◽

Peninsular Malaysia ◽

The State ◽

Difficulty Level ◽

Standard Scale ◽

Water Recreation ◽

Tourism Activity ◽

White Water ◽

Main Attraction

In Malaysia, there are many rivers that are being the attraction for white water river activities. Perak, is a state on the west of Peninsular Malaysia has several rivers that are suitable for white water river activities and being among the favourite location for white water river activities enthusiasts. Among the well-known white water rivers in Perak state are Kampar River, Slim River, Sungkai River, Singgor River and Sungai Bernam River. The attraction of a white water river depends on several factors. One of the important factor is the classification of rapid difficulty level. To date, the classification of rapid difficulty level in Malaysia is based on the international standard scale and certified by The International Canoe Federation (ICF). Apart from that, other attraction factors such as river water quality, geographical location, logistics facilities, transportation access, facilities, operator reputations and promotions are among other attraction factors. This present study aims to identify the main attraction factors in the white water rivers in Perak State. Dynamic and structure profiling of the rivers was produced. The white water rivers selected in this study were Kampar River, Slim River and Sungkai River. From the study, Kampar River was identified to be the most preferred river for white water activities compared to Slim River and Sungkai River. Findings from the study was resourceful in the effort of constructing a complete profile of white water rivers structure located in the state of Perak besides promoting white water river activities as a structured recreational tourism activity in Perak.

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Biogeochemistry of the Dumai River estuary, Sumatra, Indonesia, a tropical black-water river

Limnology and Oceanography ◽

10.4319/lo.2007.52.6.2410 ◽

2007 ◽

Vol 52 (6) ◽

pp. 2410-2417 ◽

Cited By ~ 36

Author(s):

M. Alkhatib ◽

T. C. Jennerjahn ◽

Joko Samiaji

Keyword(s):

River Estuary ◽

Black Water ◽

Black Water River

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