Monitoring, quanitfying, and simulating the internal biological processes of a constructed municipal wastewater treatment wetland in the Georgia piedmont

Abstract

The internal physical, chemical, and biological processes and interactions are often neglected in constructed wetland design, operations, and maintenance procedures, although a tremendous amount of research has been conducted and numerous publications exist concerning natural and constructed freshwater marsh wetland structure and function. The research presented in this dissertation was conducted in order to better understand the biological and ecological processes by which a constructed wetland treats wastewater in the Georgia Piedmont. The primary objective of this study was to better understand and estimate the processes that govern the fate and transport of nutrients through such a system. The major biogeochemical and ecological processes involved in treatment of wastewater with constructed wetlands include: 1) the uptake and assimilation of nutrients by vegetation; 2) the contribution of dead vegetative biomass to the organic content of sediment; 3) the microbial decomposition of vegetative organic material; 4) the microbial activity resulting in nitrification of ammonia-nitrogen and denitrification of nitrate-nitrogen; and 5) the physicohemical and microbial processes leading to the sorption and decomposition of phosphorus compounds. A monitoring and modeling approach was used in this study to attempt to better understand the processes responsible for wastewater treatment. The focal study site was the Tignall Water Reclamation Facility, located in Tignall, GA.