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Efficiencies of Substrates, Vegetation, Water Levels and Microbial Populations
Published in Donald A. Hammer, Constructed Wetlands for Wastewater Treatment, 2020
Many lakes and streams are showing signs of excessive fertilization due to the input of aquatic plant nutrients from anthropogenic sources. Drinking water treatment difficulties presented by algal development in reservoirs can be prevented, first of all, by lowering nutrient input into drinking water reservoirs. One possible intervention is to use naturally growing periphyton communities on artificial substrata to lower nutrient loads in reservoir tributaries. This chapter evaluates the efficiency of periphyton communities in nutrient elimination in a continuous-flow trough in the field. Periphyton growth could be used either in waterworks pretreatment, especially in small eutrophic tributaries to drinking water reservoirs, or in the tertiary treatment process. Before use, however, it would be necessary to check the response under different environmental conditions such as current velocity, influent concentrations of nutrients, size and composition of artificial substrata, or position of the substrata in the trough.
Northern River Basins Study and the Athabasca River: The Value of Experimental Approaches in a Weight-of-Evidence Assessment
Published in Susan B. Norton, Susan M. Cormier, Glenn W. Suter, Ecological Causal Assessment, 2014
Alexa C. Alexander, Patricia A. Chambers, Robert B. Brua, Joseph M. Culp
Phosphorus and nitrogen were found to increase downstream from each pulp mill and sewage outfall, as did periphyton biomass. During these intensive sampling periods, periphyton was collected by scraping known areas on rocks collected from several riffles at multiple sites along the river to evaluate biomass (expressed as chlorophyll a content). Algal biomass (see Figure 24.2) increased immediately downstream from every effluent source, never exceeding a threshold value of <500 mg/m2 chlorophyll a and reverting to background concentrations within 30 km of an outfall. During the late fall, the effects of the waste and pulp-mill effluents were exaggerated due to lower flows.
Relationships of Water Level Fluctuations and Fish
Published in Harold H. Prince, Frank M. D’Itri, Coastal Wetlands, 1985
Charles R. Liston, Saralee Chubb
We suggest that maintenance of relatively high, stable water levels during post-spawning periods is important for production of food for larval fishes, especially when they begin feeding exogenously after yolk sac reabsorption. Growth of attached algae, fungi and associated animals on stems and leaves of plants may amount to 100–500 g dry wt/m2 during some periods of the year (Westlake, 1966). Production of periphyton on stems and surfaces of littoral aquatic vegetation may supply significant food for micrograzing invertebrates which in turn may be eaten by larval fish. In fact, some investigations suggest that the “critical period” regarding survival of year classes may be in the larval stage when exogenous feeding begins (Braun, 1967; Cushing, 1974). Relatively small changes in wetland water levels during spring and summer may result in large changes in total surface area of plants available for production of periphyton. Recent insight into this phenomena has been gained through studies of periphyton productivity in wetlands of the St. Marys River (McNabb, 1984). McNabb studied the net productivity of periphyton on live and dead stems of hard-stem bulrush (Scirpus acutus) and bur reed (Sparganium eurycarpum), and extrapolated the results over a square meter of wetland under various water depths, giving estimates of the areal periphyton productivity (mg C/m2 wetland/day). The effects of water depths on periphyton productivity growing on high density stands of hard-stem bulrush may be seen in Figure 6. This influence is exerted through its effect on leaf and stem area per unit area of wetland available for periphyton development. McNabb concluded that either a change in water depth or emergent stem density may significantly change periphyton production. A potential loss of periphyton production with lowered water levels should be considered in future decisions regarding water diversion from the Great Lakes (Manny, 1984).
Occurrence and potential harms of organochlorine pesticides (OCPs) in environment and their removal by periphyton
Published in Critical Reviews in Environmental Science and Technology, 2023
Cilai Tang, Zhihao Chen, Yingping Huang, Inna P. Solyanikova, S. Venkata Mohan, Hongfeng Chen, Yonghong Wu
Periphyton is a complex community of algae, bacteria, fungi, protozoans and metazoans etc. that grow on submerged substrate surfaces (Wu et al., 2012, 2018). Moreover, some inorganic minerals (e.g., Fe, Mn and Al-containing compounds) and organic compounds secreting from periphyton coexist with periphyton to be a special aggregate (Wu et al., 2012). Periphyton plays important roles in primary production, as a basal food resource for higher trophic levels, and for carbon and nutrient cycling in freshwater ecosystems (Konschak et al., 2021; Wu et al., 2018). Due to its widespread distribution in environment and unique population structure, strong adaptability to the environment, periphyton is often used to treat various pollutants such as sulfonated azo dye methyl orange (C14H14N3SO3Na) (Shabbir et al., 2017), tetracycline (C22H24N2O8) (Quinlan et al., 2011), microcystin RR (Wu et al., 2010), phosphorus (P) (Lu et al., 2014), arsenic (As) (Guo et al., 2020; Usman et al., 2013), lead (Pb) (Stewart et al., 2015; Usman et al., 2013), cadmium (Cd) (Yang et al., 2016), copper (Cu) (Yang et al., 2016), etc. Additionally, there are many studies on the successful removal of fipronil (Pino-Otín et al., 2021), diuron (Chaumet et al., 2020), herbicides and persistent organic pollutants (Bighiu & Goedkoop, 2021; Chan et al., 2022; Sonawane et al., 2022) using periphyton. However, to the best of our knowledge, no review has explored the current advances in the use of periphyton for the treatment of OCPs.