Phosphorus removal and the inhibition of micro-algal species growth in the presence of Spirogyra were investigated,aiming at phosphorus removal and the inhibition of micro-algal species growth in eutrophicated water b...Phosphorus removal and the inhibition of micro-algal species growth in the presence of Spirogyra were investigated,aiming at phosphorus removal and the inhibition of micro-algal species growth in eutrophicated water bodies.Inhibition of micro-algal species by Spirogyra was studied with Microcystis aeruginosa,a representative of blue algae,and Scenedesmus as a representative of green algal species.Co-cultivation experiments showed that Spirogyra inhibited the growth of the two algal species and Chlorella species strongly.The poor growth of Microcystis aeruginosa and Scenedesmus may result from the metabolic secretions of Spirogyra or microorganisms accreted with Spirogyra by a series tests,such as Spirogyra co-cultivating with Microcystis aeruginosa and Scenedesmus,culture liquid and filtered culture liquid of Spirogyra affacting growth of Microcystis aeruginosa and Scenedesmus.The experiments were conducted on simulated lake water with a phosphorus concentration of less than 1.6 mg·L-1,and phosphorus was removed efficiently during the growth of Spirogyra.The composition of nitrogen nutrients affected the phosphorus removal efficiency,reaching a maximum when the ratio of NH+4-N to NO-3-N was 3∶7.The changing ratio of inorganic nitrogen to phosphorus during Spirogyra growth showed that phosphorus precipitation,which was induced by an increase of pH,was also an important mechanism for phosphorus removal in addition to assimilation by Spirogyra.The cultivation of Spirogyra,which inhibits micro-algal species growth and removes phosphorus,provides a new method to bioremediate eutrophicated water bodies and to protect raw water resources.展开更多
The freshwater alga Spirogyra grevilleana was used in an experimental biofiltration system to reduce levels of Escherichia coli, nitrates, and phosphates. Water collected from a 2.32 ha lake in Atlanta, Georgia, USA w...The freshwater alga Spirogyra grevilleana was used in an experimental biofiltration system to reduce levels of Escherichia coli, nitrates, and phosphates. Water collected from a 2.32 ha lake in Atlanta, Georgia, USA was pumped at a constant rate (6.17 × 10-1 m3·hr-1) through the algal filtration devices with low and high concentrations of S. grevilleana. Effluent water was tested over time for E. coli, nitrate, phosphate, dissolved oxygen, and pH levels. Both concentrations of S. grevilleana reduced E. coli by 100% and significantly reduced nitrate concentrations (30% ± 13%) and phosphate concentrations (23% ± 5%) while maintaining dissolved oxygen and pH at normal levels. Utilizing S. grevilleana in an algal filtration device could potentially provide a sustainable, flexible, and low-cost method of E. coli reduction in freshwater lakes worldwide. Initial results indicate that the use of S. grevilleana in conjunction with an algal filtration device is potentially capable of creating potable water.展开更多
文摘Phosphorus removal and the inhibition of micro-algal species growth in the presence of Spirogyra were investigated,aiming at phosphorus removal and the inhibition of micro-algal species growth in eutrophicated water bodies.Inhibition of micro-algal species by Spirogyra was studied with Microcystis aeruginosa,a representative of blue algae,and Scenedesmus as a representative of green algal species.Co-cultivation experiments showed that Spirogyra inhibited the growth of the two algal species and Chlorella species strongly.The poor growth of Microcystis aeruginosa and Scenedesmus may result from the metabolic secretions of Spirogyra or microorganisms accreted with Spirogyra by a series tests,such as Spirogyra co-cultivating with Microcystis aeruginosa and Scenedesmus,culture liquid and filtered culture liquid of Spirogyra affacting growth of Microcystis aeruginosa and Scenedesmus.The experiments were conducted on simulated lake water with a phosphorus concentration of less than 1.6 mg·L-1,and phosphorus was removed efficiently during the growth of Spirogyra.The composition of nitrogen nutrients affected the phosphorus removal efficiency,reaching a maximum when the ratio of NH+4-N to NO-3-N was 3∶7.The changing ratio of inorganic nitrogen to phosphorus during Spirogyra growth showed that phosphorus precipitation,which was induced by an increase of pH,was also an important mechanism for phosphorus removal in addition to assimilation by Spirogyra.The cultivation of Spirogyra,which inhibits micro-algal species growth and removes phosphorus,provides a new method to bioremediate eutrophicated water bodies and to protect raw water resources.
文摘The freshwater alga Spirogyra grevilleana was used in an experimental biofiltration system to reduce levels of Escherichia coli, nitrates, and phosphates. Water collected from a 2.32 ha lake in Atlanta, Georgia, USA was pumped at a constant rate (6.17 × 10-1 m3·hr-1) through the algal filtration devices with low and high concentrations of S. grevilleana. Effluent water was tested over time for E. coli, nitrate, phosphate, dissolved oxygen, and pH levels. Both concentrations of S. grevilleana reduced E. coli by 100% and significantly reduced nitrate concentrations (30% ± 13%) and phosphate concentrations (23% ± 5%) while maintaining dissolved oxygen and pH at normal levels. Utilizing S. grevilleana in an algal filtration device could potentially provide a sustainable, flexible, and low-cost method of E. coli reduction in freshwater lakes worldwide. Initial results indicate that the use of S. grevilleana in conjunction with an algal filtration device is potentially capable of creating potable water.
