Zygnematophyceae (Streptophyta) no perifíton de lagos urbanos do município de Goiânia, Go

• Autor(a) principal: Silva, Francielle Karla Lopes da
• Data de Publicação: 2016
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/00130000015fk
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/6005
• topic: Algas; Desmídias; Estrutura de comunidade; Lagos rasos; Diversidade; Algae; Diversity; Desmids; Structure community; Shallow ponds; BOTANICA::FISIOLOGIA VEGETAL

Urban ponds comprise habitats with a great diversity biotic and abiotic. This study aimed at analyzing the community structure of Zygnematophyceae algae in the periphyton of nine urban eutrophic ponds from Goiânia, GO. Samples were collected in August 2014, in the littoral zone. Periphyton was collected from two different substrates, macrophyte petiole (epiphyton) and pebbles (epilithon). Altogether 49 Zygnematophyceae taxa were recorded, distributed in two orders, five families and 13 genus. The highest chlorophyll a value was reported at Beija-flor Pond (2.9 μg cm-2), while the smallest one at Jardim Botânico Pond (0.8 μg cm-2). The epilithon presented a relatively higher mean value (2.4 μg cm-2) when compared to epiphyton (1.5 μg cm-2), although no statistical difference were reported between the substrates (W = 51.0; p = 0.148). Among taxonomic classes, Cyanobacteria contributed most to periphyton density (6.0 × 106 ind cm-2) especially in the epilithon, representing from 70 to almost 100% in some ponds. The class Bacillariophyceae had the second highest contribution, followed by Chlorophyceae. Based on frequency of occurrence, most taxa were classified as rare, being present in less than 20% of the samples. Only Cosmarium tenue and Mougeotia sp. 3 were classified as common. The average Zynematophyceae density was 6.2 × 103 ind cm-2, representing 0.82% of the periphytic community in the epiphyton and 0.02% in the epilithon. Most taxa reported here have been cited by literature in eutrophic habitats, and may be used as biological indicators (e.g., Staurastrum volans, Pleurotaenium trabecula var. trabecula, Closterium acutum var. variabile. Some ponds with relatively high nutrient values (e.g., Flamboyant pond) also presented higher diversity, which can be explained by these taxa tolerance to their local environments.