Habitat characteristics, hydrology and anthropogenic pollution as important factors for distribution of biota in the middle Paraná River, Argentina

AbstractSixty-one specimens of the piranha Serrasalmus marginatus Valenciennes, 1837 were analyzed, aiming at assessing the community structure of their gill parasites. The samples were collected in lagoons of the Paraná, Ivinheima and Baia Subsystems within the Upper Paraná River Floodplain (Brazil). Host size and sex had little or no influence on the abundance and prevalence of parasites. The organization of the gill parasite infracommunities of S. marginatus was significantly non-random according to null models and ordination analyses. In general, parasite infrapopulations were not affected by interspecific associations or host characteristics (e.g. size, sex), what highlights the importance of local habitat characteristics to community organization of gill parasites of S. marginatus in the Upper Paraná River Floodplain.

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Nutrient Dynamics in Wetlands of the Middle Paraná River Subjected to Rotational Cattle Management

Wetlands ◽

10.1007/s13157-015-0699-2 ◽

2015 ◽

Vol 35 (6) ◽

pp. 1117-1125 ◽

Cited By ~ 10

Author(s):

Leticia Mesa ◽

Gisela Mayora ◽

Miguel Saigo ◽

Federico Giri

Keyword(s):

Nutrient Dynamics ◽

Paraná River ◽

Parana River ◽

Cattle Management ◽

Middle Paraná

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Range extension for three species of South American freshwater crabs (Crustacea: Decapoda: Trichodactylidae)

Zootaxa ◽

10.11646/zootaxa.1977.1.4 ◽

2009 ◽

Vol 1977 (1) ◽

pp. 49-54 ◽

Cited By ~ 8

Author(s):

PABLO A. COLLINS ◽

FEDERICO GIRI ◽

VERÓNICA WILLINER

Keyword(s):

Amazon Basin ◽

New Records ◽

Paraná River ◽

South American ◽

Crab Species ◽

Southern South America ◽

Parana River ◽

The North ◽

Freshwater Crabs ◽

Middle Paraná

New sampling programs have extended the distribution of three species of freshwater crabs (family Trichodactylidae): Dilocarcinus septemdentatus and Sylviocarcinus pictus from the Amazon basin to southern South America, and S. australis, from the north of Argentina southwards. The three species are now found in the floodplain of the middle Paraná River (31°39'S, 60°45'W). The extension of their distribution is approximately 500 km and 2000 km further south. The number of freshwater crab species in the alluvial valley of the Paraná River has increased by 30% with these new records.

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Food chain length in a large floodplain river: planktonic or benthic reliance as a limiting factor

Marine and Freshwater Research ◽

10.1071/mf16269 ◽

2017 ◽

Vol 68 (7) ◽

pp. 1336 ◽

Cited By ~ 1

Author(s):

M. Saigo ◽

L. Ruffener ◽

P Scarabotti ◽

M. Marchese

Keyword(s):

Chain Length ◽

Food Chain ◽

Trophic Position ◽

Paraná River ◽

The Body ◽

Parana River ◽

Ecosystem Size ◽

Food Chain Length ◽

Top Predators ◽

Middle Paraná

Food chain length (FCL) is a key integrative variable describing ecosystem functioning. The aim of the present study was to test the hypothesis that the relative importance of planktonic and benthic energy pathways is a major factor affecting FCL in the Middle Paraná River. Samples were obtained from in eight waterbodies, measuring chlorophyll-a concentrations and the abundance of benthic invertebrates and the trophic position of top predators by stable isotope analysis. There was no evidence that resource availability, disturbances or ecosystem size limited FCL. Similarly, the body size and trophic position of predators were not correlated. However, the relative abundance of planktonic and benthic resources was correlated with FCL. In addition, stable isotopes analysis showed that the benthic reliance of top predators is correlated with their trophic position. The results of the present study indicate that because the major benthic primary consumer is a large fish (Prochilodus lineatus), the size structure of individual food chains is an important factor determining FCL. Whereas in floodplain rivers large detritivorous fishes are targets of commercial fishing, overfishing in the Middle Paraná River could be expected to increase FCL, the opposite effect to that seen in marine environments.

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