Patterns of fish species richness in rivers of the central region of Argentina.
نویسندگان
چکیده
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.
منابع مشابه
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ورودعنوان ژورنال:
- Brazilian journal of biology = Revista brasleira de biologia
دوره 62 4B شماره
صفحات -
تاریخ انتشار 2002