Environmental changes on freshwater fish communities in South America in the last five decades: a case study in northeast Argentina.
Environmental changes together with other stressors, such as habitat destruction, may cause widespread extinctions, decrease in biodiversity and disrupt natural communities, resulting in novel species assemblages. South America has a large diversity of freshwater fish with complex evolutionary hi...
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Format: | Article |
Language: | English |
Published: |
Universidad Católica de Temuco
2016-09-01
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Series: | Sustainability, Agri, Food and Environmental Research |
Subjects: | |
Online Access: | http://safer.uct.cl/index.php/safer/article/view/1047/992 |
Summary: | Environmental changes together with other stressors, such as habitat destruction, may cause
widespread extinctions, decrease in biodiversity and disrupt natural communities, resulting in novel
species assemblages. South America has a large diversity of freshwater fish with complex evolutionary
histories, mainly due to the presence of a wide variety of aquatic environments. Argentina has
experienced an increase in rainfall in the last five decades leading to important climatic and
hydrological changes. These changes caused the displacement of the isohyets towards the west. This
study reports changes in the composition of freshwater fish in northeast Argentina during the last five
decades, and investigated a causal relationship between the variation in fish assemblages and climate
change.
The changes in the distribution and composition of fish communities between 1962 and 2010
were analyzed in 22 stations. These stations were grouped in relation to the ichthyogeographic
provinces: Great Rivers province (GRp) and Pampean province (Pp). The correlation between rainfall
in relation to the number of total species from each of the studied provinces showed a significant
positive correlation in Pp and not correlation in GRp. The annual mean river discharge and the number
of total species from each ecoregion showed a significant positive correlation in GRp, and not
correlation in Pp. The results of this study strongly suggest that the rainfall variations and river
discharges observed in northeast Argentina induced changes in the composition of fish assemblages
that lead to the redistribution of fish species among ichthyogeographic provinces. |
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ISSN: | 0719-3726 0719-3726 |