Artificial wetlands

In addition to the use of techniques to reduce nutrient run-off at source, entry of nutrients to lakes can be reduced by using pre-lake techniques. These include the use of artificial wetlands on inflow streams, the use of iron salt treatment in pre-lake lagoons or by installing treatment plants to remove phosphorus. 

Filtering strips Artificial wetlands Reduce water pollution Wu and Sardo (2009)... 

A combined anaerobic /aerobic biotreatment can be more effective than aerobic or anaerobic treatment alone. The simplest approach for this type of treatment is the use of aerated stabilization ponds, aerated and nonaerated lagoons, and natural and artificial wetland systems. 

Tremaine et al. (1994) conducted pilot-scale studies to compare the effect of a suspended-growth reactor and a fixed-film bioreactor with a constructed wetland environment in removing creosote-PAHs from contaminated water recovered from a wood-preserving facility. Mass balanced chemical analysis of 5 PAHs used as model constituents of creosote showed that the wetland yielded between 20 and 84% removal, whereas the fixed-film reactor yielded 90 to 99% PAH removal. Biodegradation accounted for >99% of the losses observed in the fixed-film reactor, but only 1-55% of the compounds removed in the artificial wetland was attributable to biodegradation. Again, physical sorption of PAHs, especially HMW PAHs, was found to be significant. 

Mine Drainage. In recent years it has become clear that the environmental impact of acid mine drainage can be minimized by the construction of artificial wetlands that combine geochemistry and biological treatments. These systems are being designed for a range of wastewaters, most of which fall outside the scope of this article. 

San Joaquin Valley, California, USA Preflooded sediments in artificial wetlands Agricultural irrigation drainage 13.2 Fox and Doner (2003), 2429... 

Green way M. and Simpson J. S. (1996) Artificial wetlands for wastewater treatment, water reuse and wildlife in Queensland Australia. Water Sci. Technol. 33(10—11), 221-229. 

Mercury accumulation by two species of freshwater teleosts eastern mosquitofish (Gambusia holbrookv, lake chubsucker, Erimyzon sucetta) in an artificial wetland ecosystem was sigifificantly enhanced by sulfate addition. Authors conclude that sulfate additions result in elevated production of methylmercury in sediment and porewater -possibly due to increased mercury methylation by sulfate-reducing bacteria - which is readily evident in fish and water with subsequent increases through the food web. 

In addition to habitat concerns, some artificial wetlands have been created at some locations to function as tertiary treatment or final effluent polishing steps for small municipal sewage treatment facilities. The few known cases where this has been used are located inland from the Great Lakes. While several municipal pollution control plans have seriously examined this idea, it has yet to be implemented at any sizeable facility on the Great Lakes shoreline. 

Guangzhi Sun (wastewater treatment tidal-flow artificial wetlands), Chemical Engineering, School of Engineering, Edith Cowan University (ECU), Perth, WA... 

Ma. Teresa Alarcon Herrera (water resources water treatment using artificial wetlands), Director, Durango Unit of the Advanced Materials Research Center (CIMAV), Durango, Dgo. 

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