Benthic distribution in small tropical lakes: The presence of macrophytes matters

Shimabukuro, Erika Mayumi; Henry, Raoul [UNESP]

Benthic distribution in small tropical lakes: The presence of macrophytes matters

Data

2018-04-01

Autores

Shimabukuro, Erika Mayumi

Henry, Raoul

Tipo

Artigo

Direito de acesso

Acesso restrito

Resumo

The objective of this study was to compare the structure of macroinvertebrate communities in two lakes, one with and another without macrophytes (M+ and M-, respectively). Due to the high concentration of macrophytes into the eastern portion of the M+, we expected: (i) spatial heterogeneity of environmental variables and spatial variation of benthic composition in this lake, comparing to M-, and (ii) higher richness into the macrophytal portion (eastern portion of M+), comparing to the free macrophyte portion (western portion of M+), and also a higher richness in M+ in relation to the M-. The study was conducted in two lakes marginal to a river in Southeastern Brazil. Sampling was performed in two periods in ten sites within each lake. Three replicate samples of sediment were collected with a Van Veen grab in each site and period. Abiotic variables of water and sediment were measured at each sampling site. Macrophytes clearly determined two compartments in M+. The taxa richness was higher in the eastern portion of the M+, where the macrophytes where concentrated, and even the western portion of M+ presented higher richness than M-. Chironomus paragigas Reiss 1974 (Chironomidae) predominated in M-, a homogeneous environment. In contrast, several other taxa, such as Cryptochironomus, Cladopelma, Asheum, Dicrotendipes, Procladius occurred exclusively in the lake with macrophytes, a fragmented and heterogeneous environment. Therefore, in this study macrophytes presence induced spatial heterogeneity, reflecting in benthic macroinvertebrates’ richness and distribution.