The impact of impoundment on the rotifer communities in two tropical floodplain environments: interannual pulse variations

Brazilian Journal of Biology

Cc. Bonecker¹  Asm. Aoyagui¹  Rm. Santos¹ 

[1] ,Universidade Estadual de Maringá Núcleo de Pesquisas em Limnologia Ictiologia e Aqüicultura Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos ContinentaisMaringá PR ,Brazil

关键词: rotifer;    floodplain;    reservoirs;    Paraná River;    Brazil;    rotíferos;    planície de inundação;    reservatórios;    Rio Paraná;    Brasil;   

DOI  :  10.1590/S1519-69842009000300008

来源: SciELO

【 摘 要 】

Hydrological pulses are the main factor regulating the structure of biological communities in floodplains. Reservoirs above this ecosystem change the environment's dynamics and the community's biodiversity. This study evaluated the structure and stability of the rotifer community in response to changes in hydrological pulses after the Porto Primavera impoundment in the Upper Paraná River floodplain. The community was studied in a river and in a floodplain lake downstream of the dam over a four-year period before and after the impoundment. A decrease in species richness and abundance was observed soon after the impoundment, followed by an increase in these attributes and in specific diversity when the hydrometric level of the Paraná River rose and, consequently, increased the connectivity between the floodplain environments. Conochilus coenobasis, Filinia longiseta, Keratella cochlearis, Lecane proiecta and Polyarthra dolichoptera persisted throughout the study and contributed to community stability (the maintenance of rank in species abundance over time), which was high in the floodplain lake, mainly after the impoundment. Reductions in the frequency, intensity and amplitude of potamophase pulses after the impoundment led to the decrease in species richness and the increases in abundance, community stability, and species diversity, which determine community resilience.

【 授权许可】

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