Patterns of fish species richness in rivers of the central region of Argentina

Brazilian Journal of Biology

M. A. Bistoni¹  A. C. Hued¹ 

[1] ,Universidad Nacional de Córdoba Facultad de Ciencias Exactas, Físicas y Naturales Córdoba,Argentina

关键词: fish species richness;    rivers;    altitude;    distance from source;    order;    riqueza de espécies ícticas;    rios;    altitude;    distância da origem;    ordem;   

DOI  :  10.1590/S1519-69842002000500004

来源: SciELO

【 摘 要 】

We analyzed the variation of fish species richness and trophic structure along an upstream-downstream gradient and identified the factors associated with the pattern observed. The fish community composition varied along a headwater-downstream gradient. Species richness and trophic structure decreased significantly with increasing altitude and increased with stream order and distance from source. Headwater communities showed a simple structure. Oncorhynchus mykiss was the only fish captured or noticeably dominant at high altitudes. Thus, headwater can be classified as "trout zones". From these zones to downstream areas fish communities changed because of the addition of other fish species. This phenomenon probably occurs because of an increase in habitat diversity.

【 授权许可】

CC BY   
 All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License