• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • No language data
  • Tagged with
  • 6
  • 6
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Temporal effects on orhophosphate removal from municipal wastewater in a subsurface-flow constructed wetland

Womack, Michael January 1996 (has links)
Orthophosphate removal from wastewater in a subsurface-flow constructed wetland (SFCW) was studied during the fall of 1995. The SFCW consisted of a cell with an impervious liner, filled with 1.27 to 3.81 cm river rock and planted with common reeds (Phragmites australis) and soft-stem bulrushes (Scirpus validus). Municipal wastewater was pumped through the wetland and comparisons were made between inlet and outlet orthophosphate concentrations. Comparisons were also made at locations within the cell. A mean orthophosphate reduction of 62% with a range of 91% to 32% was observed for the duration of the study. An ANOVA test showed a significant reduction of orthophosphate in the wetland cell during the study. A regression analysis indicated that inlet wastewater temperatures played a significant role in orthophosphate removal, while outlet wastewater and ambient air temperature were not a significant factor.Keywords: Subsurface-Flow Constructed Wetlands, Orthophosphate, Municipal Wastewater, Water Chemistry, Nutrients. / Department of Natural Resources and Environmental Management
2

Determining the potential for wetland construction within a linear park setting

Flaugh, Dianne L. January 1991 (has links)
The purpose of this creative project was to outline the concept of Wetland Incentive Zones and to develop a site masterplan based on this concept. Meant as an alternative to large single-site wetland banks, Wetland Incentive Zones would be linear areas of land where wetland construction and preservation efforts would be concentrated. The linear structure would distribute the benefits associated with wetlands through a greater area than would a typical wetland bank. If linked together, the zones would form a network of recreational greenways and function as a travel corridor for wildlife. Participating zone landowners would benefit from tax abatements on wetland acreage and other incentive programs. The public would benefit from the preservation and construction of wetlands and the zone's recreational and educational elements.The masterplan was developed to direct wetland site development opportunities and public recreation and educational functions within a 3200 acre study site located in Allen County, Indiana. This site masterplan identified areas suitable for wetland construction, investigated their potential as wildlife habitat, and the wetland condition likely to be supported. The development plan for the site was focused on the use of an abandoned railroad line as a trail system for public recreation and educational use. / Department of Landscape Architecture
3

Nitrogen removal and biomass production from a harvested and unharvested scirpus wetland

Schultz, Paul Eaton January 1997 (has links)
A subsurface flow constructed wetland was built at the Wastewater Treatment Plant in Muncie, Indiana, in May, 1995. In May, 1996, this wetland was divided into two equal cells and planted with Scirpus validus vahl (softstem bulrush). Samples were collected from July 30, 1996, through October 22, 1996. This study had two objectives. The first was to determine if harvesting the aboveground biomass of the Scirpus would affect the wetland's ability to remove nitrogen from the wastewater. The second objective of this study was to determine if harvesting the bulrush twice during a growing season would substantially increase the annual biomass production. Water was collected from four locations in each cell and analyzed for organic nitrogen, ammonical nitrogen, nitrate, and total nitrogen. The concentration of each nitrogen parameter was significantly reduced between the inlet and well 1 in each cell of the wetland. There were no significant reductions in nitrogen concentration in subsequent sampling locations. There were also no significant differences between the two wetland cells. / Department of Natural Resources and Environmental Management
4

Evaluating the effectiveness of commercial nitrifying bacteria in a constructed wetland

Smith, Timothy R. January 1996 (has links)
This research was conducted to determine the effects of commercially available nitrifying bacteria in a constructed wetland. The study was conducted at Paws, Inc., near Desoto, Indiana during the summer of 1995. The wetland, called Solar Aquatics Treatment System (SAS), was developed by Ecological Engineering Associates and constructed in a, greenhouse. The commercial nitrifying bacteria (Bacta-Pur), contained Nitrosomonas and Nitrobacter Spp. and have been added to the wetland for the past five years to aid in the removal of nitrogen.Water samples were taken from the wetland and analyzed for ammonia, nitrite, nitrate, dissolved oxygen, hydrogen ion concentrations and water temperature from Monday through Friday for three weeks. A baseline was established from these samples. After three weeks of testing the addition of Bacta-Pur to the wetland was discontinued.To determine whether these additional bacteria were needed, testing without the Bacta-Pur was conducted for three weeks. These samples were collected and analyzed for the same parameters as those used to establish baseline information.Ammonia concentrations were significantly lower without the addition of Bacta-Pur bacteria. There were no significant differences for concentrations of nitrite and nitrate. The water temperature was higher in the three weeks when no Bacta-Pur was added. This was due to the increase in ambient temperature which caused the water temperature in the SAS to increase. Since the nitrogen compounds either remained the same or decreased in concentration at the effluent without the addition of bacteria, the addition of Bacta-Pur is not needed in order to remain in compliance with EPA regulations for effluent standards.A container experiment was conducted to provide an' environment that had no introduced bacteria before the addition of Bacta-Pur. There were no significant differences for the nitrogen compounds between wastewater samples with addition and without addition of Bacta-Pur bacteria. / Department of Natural Resources and Environmental Management
5

Evaluation of restored wetlands using the Ohio Rapid Assessment Method

Ronald, Constance E. January 2009 (has links)
The history of wetland regulation, identification, and delineation was researched to examine the current status of wetland assessment. One area of interest was the Natural Resources Conservation Service (NRCS) programs to construct and restore wetlands on previously farmed land. Indices of biotic integrity and other intensive assessment methods such as Floristic Quality Assessments are frequently used to document condition and quality for both natural and constructed wetlands. This research used the Ohio Rapid Assessment Method (ORAM) to evaluate five NRCS wetlands of different ages and an undisturbed natural wetland for comparison. In addition, an intensive vegetative survey was conducted at each wetland to determine the characteristics of the plant community and to create a Vegetation Index of Biotic Integrity (VIBI) based on the Ohio wetland assessment program. The goals of the research were to document the condition of the wetlands, to evaluate the use of the rapid assessment method compared to the more extensive vegetative assessments, and to examine the vegetative composition of the wetlands as a function of age since establishment under the NRCS programs. Scores determined by the ORAM and the VIBI demonstrated a close correlation. ORAM scores also correlated to Floristic Quality Assessment Index scores calculated as part of the VIBI. Scores calculated by the ORAM and VIBI were regressed against the age of the wetland. These assessment scores were not significantly related to age, however lack of significance might have been constrained by the small number of samples. This research demonstrated that the rapid assessment technique used provided results comparable to more intensive methods and could provide a relatively quick and accessible method to monitor wetland condition and development. / Department of Natural Resources and Environmental Management
6

Haberek wetland creation

Sullivan, Rodney Thomas January 1992 (has links)
Wetlands in the United States have been decreasing in number from the time European settlers began draining them for agricultural purposes to the present. Wetlands serve many important ecological functions such as waterfowl habitat.The purpose of this project was to investigate wetland creation literature in order to develop a process which could be applied to a particular site to attract waterfowl. The topics reviewed for this project were goal setting, for wetland creations, wetland creation methodologies and waterfowl habitat criteria. The major portion of the project was devoted to the construction process of the wetland. The criteria used to direct the wetland construction were hydrology, topographic contour design, revegetation, and protective buffers. Trail development to provide public access for educational purposes was also an important component of the wetland design. Waterfowl habitat criteria was also researched and applied to the project in order it insure that waterfowl would be attracted to the wetland.The process developed from the research was applied to Jim Haberek's property located in Anderson, Indiana. The product was a masterplan which included a site analysis, a water level management plan, a contour design, a revegetation plan, protective buffers and a trail design for the public. / Department of Landscape Architecture

Page generated in 0.0557 seconds