The Response And Feedback Of Periphyton During Chronic Nanotoxicity Based On New Cultivated Technology

Periphyton is a micro-ecosystem, usually consists of an aggregate of bacteria and algae. Researchers have found that it has been widely used in aquaculture and environmental remediation, because of its complex community and food web. The stability and the diversity of periphyton is dominated by the transfer of oxygen, energy and nutrient. And, the nanotoxicity is frequently studied by researchers because nanoparticles(NPs) are increasing used in consumer goods and are entering waters, thereby exposing and potentially affecting biota.Herein, we selected and modified agriculture byproducts(peanut shell and rice husk), then peanut shell(PS), rice husk(RH), decomposed peanut shell(DPS), acidified rice husks(ARH) and commonly carriers- ceramsite(C, as the control) were used to support the growth of periphyton. Those materials selected as carriers had been systematically investigation to explore the relation between periphyton and carriers. Moreover, periphyton with stable system were selected to asses the nanotoxicity. The aim of this study is to improve the technology of wastewater treatment by periphyton based on recycling agrowaste.Results of showed that DPS and ARH supported significantly higher periphyton biomass and metabolic versatility than PS and RH, respectively due to the increased presence of e groups. The total nitrogen(TN) and total phosphorus(TP) captured by periphyton were enhanced by 600-657% and 833-3255% for DPS, 461-1808% and 21-308% for ARH respectively. The removal of nutrients from simulated eutrophic surface waters using periphyton attached to DPS was improved by 24-47% for TP, 12-48% for TN and 15-78% for nitrate compared to the control. The results indicate that the periphyton attached to modified agrowaste was capable of efficiently entrapping and storing N and P from eutrophic water. At last, a series of 10 days exposure experiments of 10 mg/L NPs(CeO2, Fe2O3 and TiO2) on periphyton were conducted. Results showed that an assemblage attached on the periphyton and embedded into the cell would increase the oxidative stress and impair organism on/in periphyton, but the influence on bacterial community metabolic diversity(richness, evenness) was not obvious.Based on previous reports and the results of our study, the physicochemical properties of carriers have an main influence on the growth and stable of periphyton. The periphyton attached to modified agrowaste entrapping and storing N and P from eutrophic water lay a foundation for developing biofertilizer. Ultimately, to interpret the effect and eventual fate of engineered materials in the environment, an understanding of the relationship between nanoparticle properties and responses at the molecular, cellular and community levels will be essential for practical research.