Multiple Choice
Species composition was analyzed for fish communities in two Brazilian rivers.The higher (headwaters) , middle, and lower (floodplain) sections of both the Iguatemi River and the Jogui River were sampled.The Iguatemi had 34 species and the Jogui had 31.In both rivers, some species occurred only in the headwaters, others only in the floodplains.Water velocity decreased and turbidity increased from the headwaters to the floodplains.Neither river had rooted vegetation, and the communities did not differ significantly from season to season.The factor most important in determining species composition in the two rivers was most likely
A) temperature.
B) prevalence of non-rooted vegetation.
C) changing characteristics from headwaters to floodplains.
D) richness of fish species.
E) presence of endangered species.
Correct Answer:

Verified
Correct Answer:
Verified
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