Community structure of periphytic Zygnematophyceae (Streptophyta) in urban eutrophic ponds from central Brazil (Goiânia, GO)

Abstract

Aim This study aimed to investigate the community structure of Zygnematophyceae algae in the periphyton of nine shallow urban eutrophic ponds from central Brazil. Additionally, we compared two different substrates, hypothesizing that community structure attributes (chlorophyll a; Zygnematophyceae density, composition and richness) would differ between them. Methods Samples were carried out in August 2014. Periphyton was collected from two different substrates, macrophyte (epiphyton) and rocks (epilithon). Results The ponds presented pH ranging from neutral to slightly acidic and electrical conductivity in general higher than 60 µS.cm-1. Zygnematophyceae contributed with 0.82% of total periphyton community density in the epiphyton and 0.02% in the epilithon. Altogether 49 Zygnematophyceae taxa were recorded, distributed in 13 genera. Based on frequency of occurrence, most taxa were classified as rare, being present in less than 25% of the ponds. The taxa with higher densities were Cosmarium regnesii var. regnesii, Cosmarium abbreviatum var. minus, and Mougeotia sp. 3. When each pond was considered individually, other taxa were highlighted as the most abundant among Zygnematophyceae. It was the case of Staurastrum smithii, Cosmarium exiguum, Mougeotia sp. 1 and Mougeotia sp. 2. The two ponds with highest Zygnematophyceae density showed high similarity in the species composition (>70%); however, among the others, it was relatively low (<50%). Conclusions The eutrophic ponds considered in this study presented high periphytic biomass, but with low Zygnematophyceae representativeness. The periphyton attributes were not significantly different between macrophytes and rocks. The substrate type was not a determinant factor for Zygnematophyceae periphytic algae in the studied ponds.

Spatiotemporal Variation on Water Quality and Trophic State of a Tropical Urban Reservoir: A Case Study of the Lake Paranoá-DF, Brazil

“…where: [TP] is the total P concentration of the lake water in mg L −1 , LP is the P loading rate, TR is the calculated retention, and Z is the average reservoir depth [31,33]. The model proposed by Lamparelli [33,35] for tropical reservoirs was developed from the classic model of Carlson (1977) and established new relationships to determine the TSI, generating the model that uses concentrations (µg L −1 ) of: total phosphorus (TP) (Equation ( 2)) and chlorophyll a (Chl-a) (Equation ( 3)), and calculating the value of the TSI (Equation ( 4)) from the average of the indexes obtained through Equations ( 2) and (3).…”

“…Water quality and productivity of lakes and reservoirs are largely controlled by the quantity and quality of external nutrient loads [1]. An excess of nutrients, in turn, can greatly intensify the natural eutrophication process, currently considered as one of the main problems affecting water quality [2,3]. Furthermore, climate warming will tilt the CH 4 balance towards higher lake emission with this impact exacerbated by the eutrophication of the lakes [4].…”

Cultivation and Photophysiological Characteristics of Desmids in Moderately Saline Aquaculture Wastewater

“…In addition, more recent floristic investigations demonstrate that many desmids known as indicators of oligotrophic conditions have been commonly found in meso‐eutrophic to eutrophic waters, while eutrophic taxa have been frequently recorded in effluents from agricultural complexes (Fehér 2003, Stamenković and Cvijan 2008, Ferragut and Bicudo 2009, 2012, de Silva et al. 2018). In general, this indicated that desmids shifted their optima to high concentrations of nutrients and various pollutants, thus, some of them could possibly be used as absorbents of excess nutrients in wastewaters.…”