Structural changes of the phytoplankton and epiphyton in an urban hypereutrophic reservoir

Abstract

Aim This study evaluated the temporal changes of phytoplankton and epiphyton structure and their relationships with limnological factors in an urban hypereutrophic reservoir (Rasgão Reservoir, Brazil). Methods We collected water sample and phytoplankton in different depths at two sites (dam and near tributary input) in summer and winter 2010. Epiphyton on Salvinia spp. was sampled only at site near the tributary input. We determined limnological variables and structural attributes (species composition, density, biovolume, descriptors species, diversity) for both communities. Results Phytoplankton density and epiphyton density and biovolume were higher in the winter (dry season), which occurred the higher nutrient concentrations and lower water flow. Chlorophyceae was dominant in the phytoplankton in both period and Cyanobacteria was the second most abundant class in the winter. In the epiphyton, Bacillariophyceae was dominant in the summer and Cyanobacteria in the winter. The increase in light availability and water flow can have provided high species richness and diversity in the summer. Conclusion Temporal changes in the structure of phytoplankton and epiphyton on Salvinia were more related to increased nutrients availability (nitrogen and phosphorus) and flow variations in a hypereutrophic reservoir.

Response of Epiphytic Algae to Heavy Pollution of Water Bodies

“…Conversely, an increase in the contribution of Bacillariophyta and a decrease in the contribution of Chlorophyta were observed in studies of littoral periphyton of the heavily polluted Lake Orta (Italy) after its recovery (Cattaneo, 2011). The increase in epiphyton numbers and biomass in response to contamination by organic matter and nutrients was registered in small rivers in the urban territories of Karelia and the Kolsk peninsula (Komulaynen, 2008), in heavily polluted rivers of the Leningrad region (Stanislavskaya, 2006), and also in a hypereutrophic reservoir of Brazil (Santana and Ferragut, 2016). Changes in the composition of the dominant complex of epiphyton in response to contamination were observed in small rivers in urban territories (Komulaynen, 2008) and also in a lake subjected to the influence of oil contamination (Stenina, 2003).…”

“…The obtained results correlate well with literature data. A decrease in periphyton species richness was observed in response to an increase in the degree of anthropogenic load on water bodies, including the increase in the degree of anthropogenic eutrophication (Stanislavskaya, 2006;Santana and Ferragut, 2016). A decrease in the number of species with a low frequency of occurrence and sensitive to contamination was registered in studies of the response of macrophytes to the influence of anthropogenic factors in the Vorskla River (Ukraine) (Karpova and Klepets, 2014).…”

“…In this case, nitrogen and phosphorus are the primary nutrients influencing the growth of epiphyton. For example, periphyton species richness decreased in response to an increase in the degree of anthropogenic eutrophication (Santana and Ferragut, 2016;Stanislavskaya, 2006). In addition, it has been found that the contribution of Chlorophyta and Cyanoprokaryota increased, whereas the contribution of Bacillariophyta decreased when increasing the nutrient concentration (Cattaneo et al, 2011;Komulaynen, 2008).…”

Water quality assessment of a temperate urban lagoon using physico-chemical and biological indicators

“…It is possible to find numerous scientific studies on urban lagoons in the world [33,59,63,80], showing the importance they have in the cities. Conversely, the Latin American cities have given little importance to these ecosystems in urban ecology, despite the accelerated losses of biodiversity [83].…”