Dissertations / Theses: 'Urban wetlands'

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Steinman, Alexis. "Assessment of Wetland Water Quality and Plant Species Composition across the Rural, Peri-Urban, and Urban Gradient." Thesis, North Dakota State University, 2017. https://hdl.handle.net/10365/28381.

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The Prairie Pothole Region, specifically eastern North Dakota, has experienced intense disturbance from agricultural demands and urban sprawl. This study assessed wetlands across the rural, peri-urban, and urban gradient to determine the impacts of urbanization on water quality and vegetation composition. Thirty wetlands were randomly selected and compared based on land use type and the impervious to pervious surface ratio within one mile of each wetland. Water quality samples were taken in 2015 and 2016, and a vegetation assessment was completed at all wetlands. Results indicate disturbance from urbanization impacts wetland water quality and vegetation composition. Rural wetland water quality and vegetation significantly differ from both peri-urban and urban wetlands, whereas peri-urban and urban wetland water quality and vegetation do not differ. Information from this study is useful to wetland professionals across the globe as urban development and sprawl continue to impact wetlands.

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Yung, Sonja Burns. "Measurement of sediment oxygen demand in a created urban wetland." Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-08222009-040211/.

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Conran, Leigh Garde. "Establishment vegetation patterns in an artificial urban wetland as a basis for management." Title page, contents and abstract only, 1991. http://web4.library.adelaide.edu.au/theses/09ENV/09envc754.pdf.

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Cutbill, Linda Beverley. "Urban stormwater treatment by artificial wetlands." Thesis, University College London (University of London), 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266138.

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Balderas-Guzmán, Celina. "Strategies for systemic urban constructed wetlands." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/80907.

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Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2013.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (p. 121-128).
As a result of ubiquitous impermeable surfaces, conventional water management and stormwater infrastructure, and the resultant degradation of natural hydrologic networks, most American urban areas have suffered severely compromised hydrological function and health, particularly related to stormwater and its storage, treatment, and flow. Negative externalities exist at multiple scales: increased disaster vulnerability, climate change, poor water quality, habitat loss, etc. Because upgrading conventional single-purpose infrastructure has become an increasingly cost-prohibitive option, urban areas are finding that reincorporating natural systems can be more effective. In the last 20 years, constructed wetlands have arisen as a promising multi-purpose solution to stormwater problems. Constructed wetlands are artificial systems designed to mimic natural wetlands by using the same physical, biological, and chemical processes to treat water. They are relatively large, but their size gives them high ecological potential and numerous other benefits, such as flooding protection and recreational spaces, while having low life-cycle costs. Since the effectiveness of constructed wetlands comes from mimicking natural wetlands, then the analogy to nature should be extended as far as possible. In nature, wetlands are a system connected to a regional hydrologic network. Therefore, constructed wetlands distributed systemically throughout a watershed have potential to deliver more networked benefits than the current practice of dispersed and disconnected wetlands for individual sites. Yet little research exists examining the implications of urban constructed wetlands in design and planning terms, at multiple scales. In fact, few urban constructed wetland projects for stormwater exist in the first place. This thesis proposes a framework for understanding the potential of systemic constructed wetlands as landscape infrastructure in urban areas. Based on an understanding of science, engineering, and urbanism, this thesis identifies the urban zones of greatest potential for stormwater constructed wetlands and suggests the benefits that could arise out of an urban constructed wetland system, beyond simply water treatment.
by Celina Balderas-Guzmán.
S.M.
M.C.P.

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Wang, Chih-Yu. "Floating wetlands for urban stormwater treatment." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/52036.

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A floating treatment wetland (FTW) is an ecological approach which seeks to reduce point and nonpoint source pollution by installing substrate rooted plants grown on floating mats in open waters. While relatively novel, FTW use is increasing. A review of literature identified several research gaps, including: (1) assessments of the treatment performance of FTWs; (2) evaluations of FTWs in the U.S., particularly within wet ponds that receive urban runoff; and (3) plant temporal nutrient distribution, plant growth rate, and the long-term persistence of the FTWs in temperate regions with periodic ice encasement. An assessment model, i-FTW model, was developed, and its parameter s fitted based on data from 14 published FTW studies in the first research topic. The estimated median FTW apparent uptake velocity with 95% confidence interval were 0.048 (0.018 - 0.059) and 0.027 (0.016 - 0.040) m/day for total phosphorus (TP) and total nitrogen (TN), respectively. The i-FTW model provided a more accurate prediction in nutrient removal than two common performance metrics: removal rate (mg/m2/day) and removal efficiency (%). In the second research topic, the results of a mesocosm experiment indicated that FTWs with 61% coverage, planted with pickerelweed (Pontederia cordata L.) or softstem bulrush (Schoenoplectus tabernaemontani), significantly improved TP and TN removal efficiency of the control treatment by 8.2% and 18.2%, respectively. The pickerelweed exhibited significantly higher phosphorus and nitrogen removal than the softstem bulrush when water temperatures were greater than 25 deg C. Field observations in the third research topic found that pickerelweed demonstrated higher phosphorus removal performance (7.58 mg/plant) than softstem bulrush (1.62 mg/plant). Based on the observed seasonal changes in phosphorus distribution, harvest of above-ground vegetation is recommended to be conducted twice a year in June and September. Planted perennial macrophytes successfully adapted to stresses of the low dissolved oxygen (DO) concentrations (minimum: 1.2 mg/L), ice encasement, and relatively low nutrient concentrations in the water (median: 0.15 mg/L TP and 1.15 mg/L TN). Systematic observation of wildlife activities indicated eight classes of organisms inhabiting, foraging, breeding, nursing, or resting in the FTWs. Recommendations for FTW design and suggestions for further research are made based upon these findings.
Ph. D.

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Al-Isawi, R. H. "Urban wastewater treatment with mature constructed wetlands." Thesis, University of Salford, 2016. http://usir.salford.ac.uk/41423/.

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Despite the global acceptance for the application of vertical-flow constructed wetlands (VF CWs) as sustainable and cost-efficient technology in treating various types of wastewater, including urban wastewater, continuous loading of wetlands over time can lead to performance inefficiency and generate operational problems especially when high shock loads, such as petroleum hydrocarbon spills, are subjected to the system. Contamination with petroleum hydrocarbon compounds results in changing the structure, function and ecosystem service values of wetlands, which can eventually lead to clogging of the wetland substrate and affect the life time of the system. Sound knowledge of long-term performance in mature vertical-flow constructed wetlands linked with hydrocarbon treatment processes is needed to make guided judgments about the probable effects of a given suite of impacts and revise the management plans accordingly. A study was conducted to compare the impact of different design (aggregate size) and operational (contact time, rest time and chemical oxygen demand (COD) loading) variables on the long-term and seasonal performance of vertical-flow constructed wetland filters operated in tidal flow between June 2011 and March 2016. Ten different vertical-flow wetland systems were planted with Phragmites australis (Cav.) Trin. ex Steud. (Common Reed). Approximately 130 and 975 grams of diesel fuel (equivalent to 20 and 150 grams/litre, respectively) were each poured into four wetland filters on 26/09/2013 and 26/09/2014 respectively. Overall findings showed that the mature wetland system improved the water quality except for ortho-phosphate-phosphorus (PO₄-P), which reduced less over time. Findings also indicated that the wetland filter with the highest chemical oxygen demand (COD) loading but no diesel contamination performed the best in terms of COD and biochemical oxygen demand (BOD) removal. Filters contaminated by diesel performed worse in terms of COD and BOD but considerably better regarding nitrate-nitrogen removal. The removal efficiencies dropped for those filters impacted by the diesel spills. Seasonal analysis for water quality from different wetlands showed clear seasonal outflow concentration trends (low in summer) for COD, and nitrate-nitrogen (NO₃-N) while effluent BOD showed high treatment performance in winter. No clear seasonal trend for ammonia-nitrogen (NH₄-N), PO₄-P or suspended solids (SS) was noted. Serious clogging phenomena, impacting negatively on the treatment performance and the hydraulic conductivity, were not observed. The simulation model confirms the experimental findings that notable wetland clogging restricting the operation did not occur. Moreover, results showed that small aggregate diameter, low inflow COD load, and high contact and rest time were most efficient in reducing SS accumulation within the wetland filter bed. With regard to the treatment performance of the hydrocarbon contaminants, results indicated that all wetland systems had a relatively good performance in treating petroleum hydrocarbon compounds and the evaluation showed that all the hydrocarbon components were highly degraded and their concentrations were reduced in all treated effluents of wetland filters with time. This indicates that VF CW zones provide appropriate conditions for high treatment capacity of diesel compounds spilled with urban wastewater by a combination of processes taking place in the wetland filters, thus minimizing hydrocarbon compounds within the filter. A new experimental artificial ponds system, including: ponds with wastewater; ponds with wastewater and reeds; and ponds with wastewater, reeds and aeration, was operated in parallel with the mature experimental vertical-flow constructed wetland system, for the period between July 2015 and October 2015, to compare performance, design and operation variables between the two treatment technologies in the treatment of urban wastewater. Findings showed that highest COD and SS removals were observed for wetlands in comparison to ponds. Moreover, mature wetlands were better in removing NH₄-N and PO₄-P than ponds unless the ponds were aerated. Both systems were linked with medium to high levels of BOD removal. The aerated pond system demonstrated better treatment performance in terms of NH₄-N and PO₄-P. The NO₃-N concentration increased in the aerated ponds reflecting the high oxygen availability. Due to increasing water scarcity and droughts, which are key concerns worldwide, there is considerable interest in recycling various wastewater streams, such as treated urban wastewater, for irrigation in the agricultural sector. Recycling of effluents from various wetland filters (with/without diesel contamination) was assessed for the irrigation of chilli plants (De Cayenne; Capsicum annuum (Linnaeus) Longum Group ‘De Cayenne’) grown in a greenhouse environment. Concerning chilli fruit numbers, findings showed that the highest fruit yields for all wetland filters were associated with those that received inflow wastewater with a high loading rate, reflecting the high nutrient availability in treated wastewater, which is of obvious importance for yield production. Findings also indicated that wetlands without hydrocarbon contamination, with small aggregate size, low contact time, and low inflow loading rate provided high marketable yields (expressed in economic return). In comparison, chillies irrigated by filters with hydrocarbon contamination, small aggregate size, high contact time and high loading rate also resulted in high marketable yields of chillies, which pointed out the role of high contact time and high inflow load for better diesel degradation rates. The overall outcome of this research could considerably contribute to optimization of the design and development of long-term operation variables for constructed wetland technology particularly in petroleum industry applications. Statistically validated long-term data interpretation can particularly help the wetland modelling community and wetland managers to define, with insight into long-term and seasonal factors, removal processes for individual water quality parameters to maximize wetlands treatment performance.

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Maulan, Suhardi. "A Perceptual Study of Wetlands: Implications for Wetland Restoration in the Urban Area in Malaysia." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/26966.

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The restoration of natural wetlands is a wonderful, noble and pragmatic idea, but such efforts often meet resistance from certain segments of society. One reason for this is that the public perceives the environment in different ways than do the experts, such as landscape architects and land managers. This dissertation analyzes peopleâ s preferences for wetlands in comparison to those of landscape architects. It specifically studies the conflict about the wetland restoration program in the Malaysiaâ s Kelana Jaya Municipal Park. This dissertation is based on data obtained from a preference survey using photo questionnaires that polled both the publicâ s and landscape architectsâ group preferences for wetlands. The data was analyzed using the Content Identifying Method (CIM) to determine group preferences for wetlands and factors that influence these preferences. Park managers from several local authorities also were interviewed to determine their expectations of public preferences and attitudes toward wetland restoration and public participation. The public and landscape architects have significantly differed in stated preferences for wetlands. The public strongly prefers park-like landscapes that demonstrate human influences and provide the potential for human involvement; in contrast, landscape architects prefer natural wetlands that are visually pleasing, with well-defined spaces, visual coherence, and visual complexity. In addition, park managers did not accurately predict the publicâ s view of wetlands. Their prediction was similar to landscape architectsâ preferences. Attitudes toward wetland activities and safety, knowledge about wetland benefits, the motivation to use urban natural open spaces, and familiarity with nature significantly affected the publicâ s preferences. Further, the motivation to use urban natural open spaces was the best predictor of publicâ s preferences. The primary implications of this dissertation are that environmental education should be a core activity in changing peopleâ s perceptions of natural wetlands and that opinions of local people should be incorporated in many aspect of wetlands restoration, planning, design, and policymaking, especially in Malaysia.
Ph. D.

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Porter, Abigail M. "Wetlands in the Urban Landscape: The Process of Wetlands Restoration in Baltimore, Maryland and Paris, France." Ohio University / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1058301973.

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Hoa, Vu Minh, and n/a. "Mosquito habitats and predation efficiency on mosquito populations in Ginninderra Wetland, Canberra, Australia." University of Canberra. Resource & Environmental Science, 1993. http://erl.canberra.edu.au./public/adt-AUC20060725.115344.

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The ecology of mosquito populations in relation to weather conditions, emergent plants and predation in an urban wetland of Canberra was studied. Anopheles annulipes, Aedes notoscriptus, Aedes australicus, Aedes alboannulata, Culex annulirostris and Culex quinquefasciatus were found. Temperature was a major climatic factor in determining the abundance of mosquito populations in the wetland. First collections and subsequent development of mosquitoes in Ginninderra wetland are likely to depend on local weather conditions each year. The wetland proper was not a suitable habitat for mosquito breeding. Tall emergent vegetation may have obstructed oviposition and predation was also important in limiting colonization by mosquitoes. Instead, isolated temporary waterbodies which were free of predators, such as ground depressions, tyre tracks, domestic waste containers, were the most important habitats for mosquitoes adjacent to the Ginninderra wetland. Field experiments found that predation of mosquito larvae by mosquitofish Gambusia qffinis and notonectids Anisops was more efficient in sunlight than shade and this was affected by the height of emergent plants.

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Young, Charissa L. "Pathogen reduction by created urban riparian wetlands in central Ohio during variable hydrologic conditions." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1229811145.

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Polifka, Jonas. "Evaluating the relative importance of stormwater for nutrient and metal contamination to the urban, groundwater dependent Yellagonga Wetlands, through wetland budgeting." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2021. https://ro.ecu.edu.au/theses/2478.

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Wetlands provide numerous ecosystem services and can be utilised as pollutant sinks, however excessive contamination of wetlands can induce adverse effects to wetland ecology and lead to degradation of its values. Runoff from precipitation mobilizes contaminants from impervious surfaces which are, in some case, transported directly to wetlands through stormwater drainage. Urban stormwater can be a significant source of contaminants to wetlands, although its overall importance needs to be assessed for each wetland individually. Wetland budgeting is a management tool used to evaluate the relative importance of contaminant sources to wetlands, by comparing contaminant loads. Environmental management of the Yellagonga Wetlands, a chain of groundwater-dependent wetlands located in southwest Western Australia, has previously focused on limiting stormwater flow to the wetland park, to minimise contaminant inputs. While this management approach was based on the notion that relatively high contaminant concentrations measured in stormwater represented high loading, this assumption was not formally verified. The broad aim of this research was to evaluate the relative importance of stormwater supplied by all major sources (atmosphere as well as surface-, ground-, and stormwater) of the Yellagonga Wetlands (Lake Joondalup, Wallubuenup Swamp and Beenyup Swamp). This broad aim was achieved by comparing annual input loads of total and dissolved nutrients (N, P) and metals (Al, Cr, Co, Cu, Cd, Hg, U, and Zn)., The study also analysed stormwater for pharmaceuticals to assess whether stormwater transports other harmful substances to the wetlands. A mixture of existing data from a variety of sources was combined with original data to calculate input loads. Specifically, surface water (quantity), atmospheric fallout (quality), and stormwater drainage (quality and quantity) were determined by this study, while the remaining components were derived externally. Budgeting indicated that atmospheric fallout contributed the overall highest masses of contaminants to the wetlands, followed by groundwater and surface water while stormwater was overall least important. These results suggest that continued management focus on the reduction of contaminant loads from stormwater may not significantly impact water quality of the wetlands, however targeting of air quality and groundwater could be beneficial for their ecological health and functionality. Contrary to common belief, the results also indicate that the excess of filterable reactive phosphorus (FRP) entering the southern section of Lake Joondalup was derived from Wallubuenup Swamp, rather than Beenyup Swamp. This finding may advance the FRP source investigation and could help lowering the chances of eutrophication and algal blooms at Lake Joondalup.

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Scholes, Lian N. L. "The use of constructed wetlands for the treatment of urban runoff." Thesis, Middlesex University, 1999. http://eprints.mdx.ac.uk/13373/.

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In 1995, the Environment Agency for England and Wales developed urban runoff treatment wetlands at two selected locations in Outer London. The systems have been monitored for a wide range of parameters including heavy metals, suspended solids and BOD over a period of two years. Seven storm events were also monitored. The ability of micro-organisms, isolated from the rhizosphere of wetland plants collected at both systems, to tolerate and accumulate heavy metals has also been investigated. This study has demonstrated that constructed wetland treatment systems are capable of reducing the pollutant loadings associated with urban runoff, and that such systems can be successfully established within urban areas. During dry weather, pollutant concentrations and loadings were typically low and associated removal efficiencies highly variable. However, during storm events, pollutant loadings increased and removal efficiencies improved, with mean removal efficiencies of 71% for Pb and 81% for Cr at the Dagenham wetland. An exception to this was for suspended solids which showed an overall increase of 99% during storm events. Several design and operational issues have been identified and addressed during the course of the monitoring programme, and recommendations for the improved design and operation of urban runoff treatment wetland systems have been made. A range of micro-organisms, isolated from both wetland systems, were able to tolerate elevated Zn and Pb concentrations. Two strains (Beauveria bassiana and Rhodotorula mucilaginosa) were selected for further work. Both strains could accumulate Zn and Pb, with B. bassiana showing a high capacity to bind Pb (maximum concentration of 136mgPb/g cells dry weight). Comparison of the growth of B. bassiana at 4°C and 30°C suggested that processes of microbial metal accumulation may occur throughout the year in treatment wetlands. The presence of Pb inside hyphae of B. bassiana, associated with hyphae walls and in the surrounding medium was confirmed. This study has found that micro-organisms isolated from urban runoff treatment wetlands can tolerate and accumulate Zn and Pb, and the application of these results to wetland treatment processes is discussed.

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Hoffer, Devin M. "OCCUPANCY OF SEMI-AQUATIC MAMMALS IN AN URBAN LANDSCAPE." OpenSIUC, 2021. https://opensiuc.lib.siu.edu/theses/2832.

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Throughout midwestern North American ecosystems, semi-aquatic mammals including beaver (Castor canadensis), mink (Neovision vision), muskrat (Ondatra zibethicus), and river otter (Lontra canadensis) co-exist in wetlands. These species are ecologically important through their manipulation of habitats and interactions with other species present. The Lake County Forest Preserve District (Lake County, Illinois) is actively restoring forest preserves using several restoration practices and are interested in how these efforts may affect semi-aquatic mammal occupancy. We studied impacts of restoration practices and other environmental covariates on detection and occupancy of the 4 aforementioned focal species. Sign surveys were conducted during December-April in 2018-19 and 2019-20. Single species, multi-season models were run in RStudio using the package unmarked. Muskrat detection (p̂ = 0.60 ± 0.03) was positively affected by survey replicate, and negatively impacted by last precipitation amount and bank angle. Beaver detection (p̂ = 0.76 ± 0.03) was positively affected by survey replicate and previous 2-week precipitation amount, and negatively influenced by bank angle. Mink detection (p̂ = 0.26 ± 0.04) was positively impacted by survey replicate, and negatively affected by last precipitation amount and previous 2-week precipitation amount. River otter detection (p̂ = 0.10 ± 0.07) was not influenced by any covariates sampled. Muskrat had the highest occupancy (ψ ̂= 0.90 ± 0.05), followed by beaver (ψ ̂ = 0.57 ± 0.07), mink (ψ ̂ = 0.57 ± 0.10), and river otter (ψ ̂ = 0.28 ± 0.18). Both muskrat and river otter occupancy were not affected by any covariates sampled. Beaver occupancy was positively impacted by stream density and number of saplings. Mink occupancy was positively affected by stream density. No focal species’ occupancies were influenced by restoration practices. From these findings, I provide recommendations for future surveys and management for semi-aquatic furbearers in urban landscapes. Thank you to the Lake County Forest Preserve District for funding my research.

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Underhill, Laura. "An analysis of the ability of small urban wetlands to treat stormwater: the case of Princess Vlei wetland, Cape Town." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/28119.

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The consequences of poor water quality on urban aquatic ecosystems have been well established by researchers worldwide. Stormwater management in the urban areas of South Africa predominately focuses on the collection and diversion of runoff into the nearest receiving water body, with little acknowledgement of the impacts on the environment. The City of Cape Town Metropolitan municipality is an authoritative entity on Cape Town pollution and has acknowledged that polluted stormwater is a significant contributor to the deterioration of its' urban aquatic ecosystems due to the persistence of conventional drainage systems. Small urban wetlands are often overwhelmed by the quality of stormwater and urban runoff. Thus water bodies receiving urban stormwater runoff often have elevated loadings of pollutants. In theory wetlands are capable of treating these pollutants and improving water quality through various ecosystem services, but understanding the performance of wetlands under varying conditions is difficult to determine. In South Africa, there is a paucity of studies focussing on the impacts of urban development on small, urban wetlands and thus their ability to provide ecosystem services. This study aimed to identify the surface water quality of Princess Vlei, a small urban wetland, over the past 8 years, and establish the ingress and outflow of the wetland. The pollutant concentrations within the wetland were best explained by the predictor variables of total rainfall and progression of time. Impacts of total rainfall differed with various parameters resulting in larger volumes of water entering the wetland either diluting pollutant concentrations or elevating pollutant concentrations. These inverse trends were proved through the significant correlations found between total rainfall and COD and total rainfall and EC, while the variable of time influenced the wetland's ability to provide ecosystem services, either through the accumulation, retention or flushing of pollutants. The accumulation of pollutants over time was identified through the increasing concentrations off COD and PO₄³⁻, with the exception of NH₃-N that decreased over time. This implies that the wetland was able to assimilate the NH₃-N but not the COD and PO₄³⁻. The results did not suggest that the wetland was able to treat the water, as the literature emphasises, rather, confirmed the pervasive impacts of the urban catchment on the ability of ecosystem services to treat water quality in the wetland.

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Carleton, James Nagle. "An Investigation of the Performance of a Constructed Wetland in Treating Urban Stormwater." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36708.

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This study investigated the pollutant removal performance of a constructed wetland treating stormwater runoff from a residential townhome complex in Manassas, Virginia. The facility was constructed by retrofitting a dry detention basin to retain a permanent shallow pool and included additional temporary storage to detain roughly the first half inch of rainfall for approximately 24 hours. Vegetation was allowed to establish itself through volunteer colonization, rather than active planting of selected wetland species.

Flow measurements showed substantially greater volume passing through the outlet than entering through the single gaged inlet. The extra volume (about 41% of the total) was attributed to ungaged overland flow which drained a wooded/grassy area adjacent to the site. Mass balance calculations employing the rational method with a runoff coefficient of 0.2 to estimate the flow from this area showed good agreement between long-term total estimated inflow and measured outflow. However, this method was not effective in accounting for the discrepancies between inlet and outlet volumes of individual storms.

Thirty-three runoff events were monitored between April, 1996 and May, 1997. Because of greater flow volumes passing through the outlet, constituent mass calculations which ignored the overland contribution generally exhibited higher loads exiting than entering the facility. With the results from a limited number of grab samples representing concentrations in overland input, estimated efficiencies improved substantially, showing overall net removal for most constituents. Less than one year after being retrofitted, the basin showed signs of beginning to develop a diverse wetland flora
Master of Science

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Chen, Yuxiao. "Zhuji wetland city stormwater recycle /." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B38297590.

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Thesis (M. L. A.)--University of Hong Kong, 2007.
Includes special report study entitled: Water level control technology in constructed wetland. Title proper from title frame. Also available in printed format.

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Lenzewski, Nikola [Verfasser], and Kai [Akademischer Betreuer] Jensen. "Plants in urban wetlands : from patterns to processes / Nikola Lenzewski ; Betreuer: Kai Jensen." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2020. http://d-nb.info/1216244677/34.

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Emery-Butcher, Holly. "The distribution and habitat association of native and introduced crayfish in urban wetlands." Thesis, Emery-Butcher, Holly (2016) The distribution and habitat association of native and introduced crayfish in urban wetlands. Honours thesis, Murdoch University, 2016. https://researchrepository.murdoch.edu.au/id/eprint/35230/.

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As urbanisation puts increasing pressure on biodiversity, there is growing need to conserve biodiversity outside of protected areas. Anthropogenic wetlands (i.e. human created) may offer a way to do this by providing habitat for species such as crayfish. As the distribution and habitat association of freshwater crayfish in Swan Coastal Plain wetlands is largely unknown, the aims of this study were: to identify the habitat characteristics associated with the presence and absence of introduced (Cherax destructor) and native (Cherax quinquecarinatus) freshwater crayfish in the Beeliar and Jandakot wetlands on the Swan Coastal Plain; to compare the distribution and habitat use of introduced C. destructor and native C. quinquecarinatus between natural and anthropogenic urban wetlands. Fifty-three wetlands were sampled for crayfish using baited box traps and sweep nets between May and September 2016. Habitat characteristics were documented using rapid assessment and water quality variables recorded. Log-linear modelling and ANOSIM were then used to examine the association between crayfish and habitat characteristics. Crayfish distribution was much more limited than expected, and they were absent from 29 (55%) wetlands. Unfortunately, C. quinquecarinatus were not found in large enough numbers to model alone, so the data from this species was pooled with that of other native crayfish. Crayfish presence was most strongly associated with water regime and wetland type. Native species were associated mainly with ease of wetland accessibility to humans and wetland type whereas invasive C. destructor was associated primarily with anthropogenic wetlands and ease of accessibility. This study increases our understanding of the distribution and habitat association of crayfishes on the SCP and has important implications in terms of community education and habitat restoration in both natural and anthropogenic wetlands.

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Rosenquist, Shawn E. "Development of the Urban Wetland Filter for Managing Phosphorus in Stormwater." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/77328.

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Degradation of surface water quality by excess nutrients in stormwater is a substantial environmental and economic problem in the U.S. Phosphorus (P) is often the limiting nutrient for harmful algal blooms and the best target to prevent degradation. Natural treatment strategies such as constructed wetlands (CW) demonstrate effective and economical P management but obstacles exist to implementation. Biological P removal has large land requirements that limit the use of best management practices (BMP) in high land-value areas. Various BMP also utilize sorption processes (SP) for P removal but variations in performance and finite sorption capacity limit SP as a viable long-term removal strategy. However, by understanding variability and making sorption capacity renewable, SP could provide, with shorter retention times, a space-efficient, long-term removal strategy. This multi-study research program developed the urban wetland filter (UWF), a concept intended to overcome the unique limitations of high land-value areas to natural treatment strategies and provide a low-cost, easily implemented BMP to meet P management goals while harvesting sequestered P for use as a fertilizer. Experimental factors included substrate and influent properties pertinent to understanding performance variation and optimizing microbial iron (Fe) reduction for rejuvenation of sorption capacity. Regarding performance, modeling identified major sources of variability including, by order of importance, magnitude of a solution/substrate concentration gradient, length of the "antecedent dry period" between loadings, and pH. Field-scale results confirmed this multifactor dependence of P-removal while also supporting the inclusion of cast-iron filings in substrate to improve P removal. Regarding rejuvenation, results indicated that microbial Fe reduction is capable of releasing previously sequestered P from substrates. A sufficient carbon source was necessary, but microbial inoculation was not necessary to facilitate Fe reduction, which released most of the previously sequestered P, albeit more slowly than P sequestration. Field-scale results indicated that Fe reduction might occur faster under field conditions, possibly due to humic acids, and that inclusion of cast-iron filings enabled additional P removal after rejuvenation by providing a conservative source of Fe for the creation of new sorption sites; however, cast-iron filings may also limit the release of P during rejuvenation.
Ph. D.

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TRISAL, SHILPA. "POLICY AND PRACTICE OF WETLANDS MITIGATION FOR AIRPORTS." University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1022860785.

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Thomas, Cory Alan. "A Study of How Changes to the Clean Water Act May Affect “Isolated” Wetlands in Hamilton County, Ohio." University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1133121431.

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Proctor, Jayce Alan. "What Would a Waterbird Do? A Study of 13 Urban Wetlands in Frisco, Texas." Thesis, University of North Texas, 2020. https://digital.library.unt.edu/ark:/67531/metadc1703373/.

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Intention for this study is driven by finding patterns that may be shown to reveal primary factors of influence for the abundance and diversity of wetland birds. These correlations may be used to promote wetland management strategies for the benefit of waterbird species, and help illuminate current local wetland conditions for waterbirds, respectively. The idea is to help enliven individuals to become a more conscious steward and manipulator of our environment through incorporating structural and biological components into wetland development and management strategies, and broadly speaking, urban development practices.

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24

Goddard, Nathaniel L. "Bird Communities of Isolated Cypress Wetlands Along an Urban Gradient in Hillsborough County, Florida." Scholar Commons, 2010. https://scholarcommons.usf.edu/etd/1643.

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Migratory bird communities are sensitive to landscape alteration. Urban development significantly impacts bird communities on breeding grounds, as well as en-route during migration. One current theory is that Neotropical migratory birds are not limited by breeding or wintering habitat constraints but by food and habitat availability along major migration routes. The eastern flyway is the route taken by neotropical land-birds through eastern North America that follows coastal areas denoted by intense urban development. Coastal areas funnel birds to major departure points along the northern coast of the Gulf of Mexico and the western coast of Florida. Birds were monitored for 12 consecutive months along a decadal time gradient of urban development. Cypress domes are present through a broad scale of urban development in Hillsborough County creating ideal natural sampling units for long term monitoring of wetland bird communities in urban areas. Residential non-migratory bird communities were least influenced by development and did not change significantly with urban development. Neotropical and short-distance migratory birds, however, declined significantly for both richness and bird abundance with increased urban land cover. Migratory birds positively correlated with forested area at a spatial scale of 500 meters surrounding sites. Wintering migrants hit a critical point in development between 10 and 20 years of age, after which they disappeared. Neotropical migrants were most sensitive to declines significantly at sites classified as heavily degraded by the UMAM (Uniform Mitigation Assessment Method) a 'wetland integrity index'.

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25

Loemker, Rabea. "Nutrient removal in a constructed wetland treating urban stormwater runoff." Thesis, Queensland University of Technology, 2002. https://eprints.qut.edu.au/36156/1/36156_Loemker_2002.pdf.

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Urban stormwater runoff is a major concern in Australia and in other parts of the world, because of its potential severe, quantity and quality related impacts on the health of environmental water systems. Many stormwater quality improvement devices (SQ IDs) have been developed over time. Constructed wetlands are a relatively new SQID, and are the specific topic of this thesis. The construction of wetlands for stormwater quality improvement has been prompted by the effectiveness of natural wetlands in storing stormwater runoff during rainfall events and improving water quality during flow through the system during dry periods. However, like other ecosystems, wetlands are profoundly complex. Wetlands for stormwater quality improvement vary greatly in performance due to differences in design, climate, catchment characteristics and other factors. In particular, nutrient removal efficiencies vary widely among wetland systems. This is a result of the lack of understanding of fundamental aspects of these extremely complex, heterogeneous systems, and of phenomena responsible for nutrient removal. In particular how these are affected by environmental conditions and system design. This thesis investigated the performance of a constructed wetland treating stormwater runoff from an urban catchment. It aims to improve understanding of the performance of wetlands in removing nutrients from stormwater runoff, in a subtropical climate. A three-year-old wetland system (Keith Boden wetland) located in an urban catchment in Brisbane, Australia, was investigated over two distinct seasonal periods, autumn and summer. Water samples were collected at eight locations in different parts of the wetland. Additionally, sediment samples were taken on the last sampling date of the autumn sampling period. Results from this study showed that this wetland system was most effective and consistent in removing nitrate and orthophosphate during both seasons (autumn and summer). However, concentrations of both nitrate and orthophosphate were considerably lower within the wetland during summer. The removal of nitrate was mainly due to denitrification. The removal process for orthophosphate varied within the two sampling periods: Biological uptake of orthophosphate appeared to be high during the summer period. The processes of orthophosphate retention during the autumn sampling period were more difficult to understand and it was more likely that uptake of orthophosphate was overshadowed by the release of orthophosphate from the sediments. Other forms of nitrogen and phosphorus that were measured displayed variable behaviour within the wetland system. During summer vertical temperature and dissolved oxygen profiling showed stratification on some occasions. A detailed discussion of the methodology and results of this study highlighted the complexity of wetland systems and showed that any study of these systems is necessarily limited. Nonetheless, the experimental studies conducted as a part of this research have provided insights into the systems functioning and greater awareness of possible behaviours. This is important knowledge to aid the monitoring, design and application of wetlands as SQIDs.

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Lambert, David J., and n/a. "Ecology of invertebrates and predator - prey interactions on mosquito larvae in urban wetlands, ACT Australia." University of Canberra. Applied Science, 1989. http://erl.canberra.edu.au./public/adt-AUC20060815.125401.

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Giralang Pond was a water body, with little emergent or submerged vegetation, designed to trap fine sediment and buffer input of rising water to Ginninderra Wetland downstream. Ginninderra Wetland was designed to retain and use sediment nutrients and other potential hazardous materials in urban run-off. Water in the Wetland was more turbid and had lower magnesium concentration, redox potentials and dissolved oxygen concentration than did Giralang Pond. Water temperature was a minimum of 4 °C in the winter and reached a summer maximum of 30 °C Giralang Pond had more organisms but fewer taxa than Ginninderra Wetland. The greatest abundance in the pond resulted principally from high numbers of two numerically dominant species Calamoecia sp. and Micronecta sp.. More organisms were found in vegetated habitats of Ginninderra Wetland than open water habitats. The number of invertebrates and the number of taxa found in Typha domingensis did not differ significantly from similar estimates for Schoenplectus validus, Gambusia qffinis was the dominant predator in both water bodies. On one occasion, G. qffinis reached population densities of 35 individuals per m-2 . G. qffinis was five times more abundant in Gininnderra Wetland than in Giralang Pond and also showed a preference for vegetated areas. G. qffinis over-grazed it's prey on several occasions. G. qffinis, invertebrate predators and prey followed a pattern of a community in a stable predator-prey cycle. Prey in early spring increased population numbers and then decreased when G. qffinis and other predators increased their numbers. The pattern was further strengthened by occurring in both areas of open water and vegetated habitat types.

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27

Kemp, Annabeth S. "Freshwater cyanoprokaryota blooms in the Swan Coastal Plain wetlands: ecology, taxonomy and toxicology." Thesis, Curtin University, 2009. http://hdl.handle.net/20.500.11937/1477.

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Relatively little published information on cyanoprokaryote (blue-green algal) blooms in the freshwater wetlands in Western Australia is available. There has been little research on the urban lakes and rivers, examining the relationship between environmental conditions and toxin-producing blooms. In this project the ecology, morphology and toxicity of cyanoprokaryota blooms in 27 metropolitan lakes and sumplands, as well as three major rivers, from 2000 to 2003, on the Swan Coastal Plain (SCP) in the southwest of Western Australia were investigated.A total of 24 species were identified and described, of which nine species had not been previously documented in the area. This included the potentially toxic species Cylindrospermopsis raciborskii, Aphanizomenon ovalisporum and Anabaena bergii var. limnetica. An illustrated guide to the common bloom-forming species was generated using conventional taxonomic criteria.Microcystis flos-aquae and Microcystis aeruginosa were the dominant bloom-forming cyanoprokaryotes, widespread in their distribution. Anabaena circinalis, A. bergii var. limnetica and Anabaenopsis elenkinii were the common filamentous species. Anabaena circinalis was common to certain freshwater sites, while A. bergii var. limnetica and A. elenkinii occurred in salinity ranging from fresh (< 1ppt) to hyposaline (3-10 ppt). Sites with similar species assemblages were identified using two-way indicator species analysis and clustering analysis. From this, a distinct distribution pattern emerged, which was defined by the main genera observed in the lakes – Microcystis, Anabaena, Aphanizomenon and Anabaenopsis.The spatial and temporal distribution of the common bloom-forming cyanoprokaryote species was examined in conjunction with spring-summer physico-chemical data using principal component analysis. It was found that pH, water temperature and electrical conductivity/salinity accounted for variations among the lakes, with electrical conductivity the variable explaining the greatest variation. Lakes located on the coast, or further inland at the base of the Darling Scarp, were more hyposaline to saline, and the remaining lakes were fresh. Although the SCP lakes form consanguineous groups based on geochemistry and hydrology, no similarities among them were found in terms of water quality.The relationship between nitrogen (N) and phosphorus (P) concentrations (total and dissolved inorganic) and cyanoprokaryote community structure (N-fixing versus non-N-fixing species) was investigated in five selected lakes; Yangebup Lake, Bibra Lake, Blue Gum Lake, Tomato Lake and Emu Lake. The lakes ranged from mesotrophic to eutrophic and supported spring-summer blooms containing multiple species. Overall an inverse relationship between cyanoprokaryote abundance and total ambient nutrient concentrations at the time of the blooms was evident. No transition in dominance in the community was observed in Yangebup Lake, Emu Lake and Bibra Lake, as they were dominated by non-heterocytic species (M. aeruginosa and M. flos-aquae) throughout spring and summer. For Yangebup Lake and Bibra Lake, the abundance of non-heterocytic species decreased concomitantly with decreasing dissolved inorganic N. In contrast, heterocytic species (A. circinalis) dominated the spring community in Tomato Lake, and summer community in Blue Gum Lake, when N and P concentrations were at their highest.The presence of microcystins in Microcystis dominated blooms was examined using high performance chromatography. A total of 32 natural bloom samples, representing 13 lakes, were analysed for microcystin variants; -LR, -RR and -YR. Twenty-eight samples proved to be toxic with the highest total microcystin concentration from 1645 to 8428.6 µg L[superscript]-1, the lowest concentrations were less than 10 µg L[superscript]-1 with some below the detection limit. Microcystis aeruginosa and M. flos-aquae were associated with these microcystin-containing blooms, although M. flos-aquae appear to be less toxic. The presence of Nodularia spumigena in the Lake Yangebup was associated with high concentrations of nodularin (1664 µg L[superscript]-1).Employing enzyme-linked immunosorbent assay for microcystins and the brine shrimp (Artemia) bioassays allowed a greater number of lake samples to be analysed and provided a rapid assessment of toxicity. The three methods for cyanotoxin detection verified Yangebup Lake, Herdsman Lake, Hyde Park, Jackadder Lake and Emu Lake as highly toxic sites. Low toxicity was demonstrated in samples from Lake Goollelal, Lake Joondalup, Lake Claremont, Blue Gum Lake and North Lake. These results provided the first evidence of cyanotoxin producing blooms in urban lakes of the SCP.A comparative study on cyanoprokaryota blooms in Swan River estuary, upper Canning River and upper Serpentine River found that these sites, although hyposaline to saline, contained species that were common in the freshwater lakes. Sampling the river systems showed M. aeruginosa, M. flos-aquae, A. circinalis, A. elenkinii and Planktothrix planctonica to be cosmopolitan in distribution, present in SCP wetlands of varied salinity. Similarities between the upper Canning River and lakes in environmental conditions and species assemblage were demonstrated using multivariate analyses.Toxin analysis of bloom samples from the Swan River and upper Canning River revealed microcystin concentrations were less than that of the surrounding lakes (1.05-124.16 µg L[superscript]-1). Similarly, nodularin concentrations were higher in Yangebup Lake than the upper Serpentine River. However, the dominance of Anabaena in Canning River samples, and the highly toxic result from the Artemia bioassay suggests microcystin is not the predominant cyanotoxin in this wetland.This study has produced an overview of the distribution and morphology of cyanotoxin-producing cyanoprokaryotes in the SCP wetlands. The data presented provide the basis for further cyanoprokaryote research in Western Australia, in particular the molecular characterisation of bloom-forming toxic species.

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28

Kemp, Annabeth S. "Freshwater cyanoprokaryota blooms in the Swan Coastal Plain wetlands: ecology, taxonomy and toxicology." Curtin University of Technology, Division of Science and Engineering, Department of Environmental Biology, 2009. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=129384.

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Relatively little published information on cyanoprokaryote (blue-green algal) blooms in the freshwater wetlands in Western Australia is available. There has been little research on the urban lakes and rivers, examining the relationship between environmental conditions and toxin-producing blooms. In this project the ecology, morphology and toxicity of cyanoprokaryota blooms in 27 metropolitan lakes and sumplands, as well as three major rivers, from 2000 to 2003, on the Swan Coastal Plain (SCP) in the southwest of Western Australia were investigated.
A total of 24 species were identified and described, of which nine species had not been previously documented in the area. This included the potentially toxic species Cylindrospermopsis raciborskii, Aphanizomenon ovalisporum and Anabaena bergii var. limnetica. An illustrated guide to the common bloom-forming species was generated using conventional taxonomic criteria.
Microcystis flos-aquae and Microcystis aeruginosa were the dominant bloom-forming cyanoprokaryotes, widespread in their distribution. Anabaena circinalis, A. bergii var. limnetica and Anabaenopsis elenkinii were the common filamentous species. Anabaena circinalis was common to certain freshwater sites, while A. bergii var. limnetica and A. elenkinii occurred in salinity ranging from fresh (< 1ppt) to hyposaline (3-10 ppt). Sites with similar species assemblages were identified using two-way indicator species analysis and clustering analysis. From this, a distinct distribution pattern emerged, which was defined by the main genera observed in the lakes – Microcystis, Anabaena, Aphanizomenon and Anabaenopsis.
The spatial and temporal distribution of the common bloom-forming cyanoprokaryote species was examined in conjunction with spring-summer physico-chemical data using principal component analysis. It was found that pH, water temperature and electrical conductivity/salinity accounted for variations among the lakes, with electrical conductivity the variable explaining the greatest variation. Lakes located on the coast, or further inland at the base of the Darling Scarp, were more hyposaline to saline, and the remaining lakes were fresh. Although the SCP lakes form consanguineous groups based on geochemistry and hydrology, no similarities among them were found in terms of water quality.
The relationship between nitrogen (N) and phosphorus (P) concentrations (total and dissolved inorganic) and cyanoprokaryote community structure (N-fixing versus non-N-fixing species) was investigated in five selected lakes; Yangebup Lake, Bibra Lake, Blue Gum Lake, Tomato Lake and Emu Lake. The lakes ranged from mesotrophic to eutrophic and supported spring-summer blooms containing multiple species. Overall an inverse relationship between cyanoprokaryote abundance and total ambient nutrient concentrations at the time of the blooms was evident. No transition in dominance in the community was observed in Yangebup Lake, Emu Lake and Bibra Lake, as they were dominated by non-heterocytic species (M. aeruginosa and M. flos-aquae) throughout spring and summer. For Yangebup Lake and Bibra Lake, the abundance of non-heterocytic species decreased concomitantly with decreasing dissolved inorganic N. In contrast, heterocytic species (A. circinalis) dominated the spring community in Tomato Lake, and summer community in Blue Gum Lake, when N and P concentrations were at their highest.
The presence of microcystins in Microcystis dominated blooms was examined using high performance chromatography. A total of 32 natural bloom samples, representing 13 lakes, were analysed for microcystin variants; -LR, -RR and -YR. Twenty-eight samples proved to be toxic with the highest total microcystin concentration from 1645 to 8428.6 µg L[superscript]-1, the lowest concentrations were less than 10 µg L[superscript]-1 with some below the detection limit. Microcystis aeruginosa and M. flos-aquae were associated with these microcystin-containing blooms, although M. flos-aquae appear to be less toxic. The presence of Nodularia spumigena in the Lake Yangebup was associated with high concentrations of nodularin (1664 µg L[superscript]-1).
Employing enzyme-linked immunosorbent assay for microcystins and the brine shrimp (Artemia) bioassays allowed a greater number of lake samples to be analysed and provided a rapid assessment of toxicity. The three methods for cyanotoxin detection verified Yangebup Lake, Herdsman Lake, Hyde Park, Jackadder Lake and Emu Lake as highly toxic sites. Low toxicity was demonstrated in samples from Lake Goollelal, Lake Joondalup, Lake Claremont, Blue Gum Lake and North Lake. These results provided the first evidence of cyanotoxin producing blooms in urban lakes of the SCP.
A comparative study on cyanoprokaryota blooms in Swan River estuary, upper Canning River and upper Serpentine River found that these sites, although hyposaline to saline, contained species that were common in the freshwater lakes. Sampling the river systems showed M. aeruginosa, M. flos-aquae, A. circinalis, A. elenkinii and Planktothrix planctonica to be cosmopolitan in distribution, present in SCP wetlands of varied salinity. Similarities between the upper Canning River and lakes in environmental conditions and species assemblage were demonstrated using multivariate analyses.
Toxin analysis of bloom samples from the Swan River and upper Canning River revealed microcystin concentrations were less than that of the surrounding lakes (1.05-124.16 µg L[superscript]-1). Similarly, nodularin concentrations were higher in Yangebup Lake than the upper Serpentine River. However, the dominance of Anabaena in Canning River samples, and the highly toxic result from the Artemia bioassay suggests microcystin is not the predominant cyanotoxin in this wetland.
This study has produced an overview of the distribution and morphology of cyanotoxin-producing cyanoprokaryotes in the SCP wetlands. The data presented provide the basis for further cyanoprokaryote research in Western Australia, in particular the molecular characterisation of bloom-forming toxic species.

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29

Naigaga, Irene. "Use of bioindicators and biomarkers to assess aquatic environmental contamination in selected urban wetlands in Uganda." Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1002603.

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Pollution of aquatic resources in Uganda is on the increase and the trends are expected to increase with increase in population size and urbanisation. Assessment and mitigation of the environmental impacts on water quality and biodiversity have now become necessary. The aim of the study was to integrate invertebrate and fish as bioindicators and fish histopathology as a biomarker in the assessment of water quality deterioration in urban wetlands in Uganda. The integration harnesses the advantages and counteracts the shortcomings of each method and thus builds a more robust diagnostic tool that gives a better view of the impacts to the entire ecosystem. Four endpoints which included, physicochemical variables, benthic macroinvertebrate bioindicators, fish bioindicators and fish histopathology biomarkers were compared between varied effluent-impacted wetlands (Murchison Bay in Kampala, and Kirinya, Masese and Winday Bay in Jinja) and a non-impacted reference wetland (Lwanika in Mayuge). Results from the effluent-impacted sites differed from the less impacted reference site. The two sampling locations at Murchison Bay (inshore and offshore) and one sampling location at Kirinya (inshore), that were highly impacted with urban effluent, showed elevated nutrient levels, low pH, dissolved oxygen and secchi depth readings. This corresponded with low invertebrate taxa and fish species diversity and richness; and severe histopathological responses in liver, gonads and gills of O. niloticus. Sensitive taxa such as ephemeroptera and trichoptera were completely absent while pollution tolerant taxa Chironomus sp, Corbicula and Oligochaeta were present. Also notable was the absence of many native haplochromines and presence of mainly Brycinus sadleri, Oreochromis niloticus and leucostictus. The organs manifested high prevalence of severe inflammatory and regressive changes and higher organ indices that fell within the pathological category. These sites were consistently classified as highly polluted under the four endpoints. The reference site was classified as least polluted while Masese and Winday Bay were moderately polluted. Results suggested that the approach of using invertebrate and fish as bioindicators and the fish histopathology as a biomarker, in relation to water quality physicochemical variables was a useful tool in highlighting the spatial differences in environmental quality.

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30

Eastough, Annaliese. "Visitor perspectives from two urban wetlands in Boorloo (Perth): The importance of birdlife and management considerations." Thesis, Eastough, Annaliese (2021) Visitor perspectives from two urban wetlands in Boorloo (Perth): The importance of birdlife and management considerations. Honours thesis, Murdoch University, 2021. https://researchrepository.murdoch.edu.au/id/eprint/64608/.

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Urban wetlands are important ecosystems that provide vital habitat for birds, as well as being popular recreation destinations for urban residents and visitors. In the modern day, many wetland areas have seen significant decline due to increased urbanisation. Visitor perspectives of wetlands are important to consider, because how wetlands are perceived influences the visitor behaviour, provision of facilities and visitor support for management and conservation. This study collected information from visitors recreating at Walliabup (Bibra Lake) and Ngurgenboro (Herdsman Lake) in Perth, Western Australia. The aims were to evaluate visitor perceptions of urban wetlands as vital bird habitat, determine the importance of birds as part of the visitor experience and visitor perceptions of the wetland’s management. An on-site visitor intercept survey was conducted over 10 weeks from November 2020 to January 2021 (n=511). Visitors readily understood the importance of wetlands for birds and rated wetland habitat importance highly. Visitors also valued aspects of these wetlands that contribute to healthy bird habitat, such as natural vegetation and water quality. While recreational activities were considered more important to visitors, acknowledging the presence of birds was nonetheless rated highly. Existing management of the wetlands was generally well received by visitors, yet it was clear that there was a perception that there is room for improvement. Conservation, recreation and community management goals were believed to be carried out well and were considered important for these wetlands. Culture and research management goals were of less importance. Visitors identified a need for further education and signage, where the cultural interpretation of the wetlands was the most commonly mentioned type of information that respondents wanted to see. A notable number of visitors observed negative impacts at the lakes (~50%) where litter and pollution, disturbance by dogs and human disturbance were the most commonly mentioned. Visitors also indicated a need to improve visitor amenities and facilities, with more bins, benches, toilets and upgraded pathways being mentioned. Overall, the results of this study highlight the importance of understanding visitor perspectives, not only to improve the visitor experience, but to also gain further insight into negatively perceived aspects of the wetlands and the relationship between humans and birds. Furthermore, management recommendations call to further visitor research across wetlands on the Swan Coastal Plain, as well as adjusting current management direction for Bibra Lake and Herdsman Lake.

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Islam, Md Kamrul. "Nutrient removal from urban stormwater using floating treatment wetland system." Master's thesis, University of Central Florida, 2011. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4936.

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Despite the technology advancement, degradation of water quality due to stormwater continues to be a significant threat to the water and ecosystems due to the exponential growth of industries and agricultural enterprises that discharge stormwater. These anthropogenic activities are the sources of high nitrogen and phosphorus quantities in stormwater, which is responsible for eutrophication phenomena and deterioration of public health. Floating Treatment Wetlands (FTWs) are a potential solution to this problem. Both microcosm and mesocosm level studies were conducted for the effective removal of nutrients in stormwater wet detention ponds with different sorption media under varying nutrient concentrations and weather conditions. Water depth, percent area coverage of the FTWs and littoral zone emergent plants were varied in order to determine nutrient removal efficiency before implementing in an actual pond. Focus has also been placed on the observations of macrophyte-epiphyte-phytoplankton interactions in order to understand temporal characteristics of ecological phenomena. Water quality parameters included Total Nitrogen, Total Phosphorus, Orthophosphate, Nitrate-Nitrogen, and Ammonia-Nitrogen in addition to in-situ parameters such as pH, Dissolved Oxygen, Temperature and Chlorophyll-a. Results clearly indicate that an FTW filled with sorption media of 80% expanded clay and 20% tire crumb can significantly promote the biomass growth. Different levels of nutrient concentrations did affect the plants' growth and cold temperature in late winter was detrimental to growth. To make the system more viable irrespective of the seasonal weather conditions, the adoption of mixed vegetation is highly recommended in the FTWs implementation.; It is also recommended that, the positioning of the floating wetlands should not be in the vicinity of the outlet of the pond as assimilated nutrient under the mat might increase the nutrient concentration in the discharged water. Finally, One-way ANOVA test is performed to check whether or not these grouped microcosms and mesocosms with differing experimental setup can be deemed statistically significant.
ID: 030422696; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Thesis (M.S.Env.E.)--University of Central Florida, 2011.; Includes bibliographical references (p. 70-74).
M.S.
Masters
Civil, Environmental and Construction Engineering
Engineering and Computer Science

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Rodrigues, Maria Estefânia Fernandes. "Levantamento florístico e distribuição de macrófitas aquáticas na Represa Guarapiranga, São Paulo, Brasil." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/41/41132/tde-09122011-135402/.

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O objetivo desse trabalho foi verificar a composição e distribuição de macrófitas aquáticas no reservatório Guarapiranga, além de contribuir para o conhecimento taxonômico das espécies. Foram realizadas coletas mensais de Julho/2008 a Junho/2009, em 20 bancos de macrófitas distribuídos ao longo de todo reservatório. Em cada banco foram coletadas e registradas as espécies presentes e coletadas amostra superficial da água para análise em laboratório do fósforo total e clorofila \"a\". In situ, foram tomadas medidas de temperatura da água, pH, CE, OD e DS. Para verificar a distribuição e relação das macrófitas com variáveis ambientais foram realizadas análises de similaridade e correspondência canônica. A comunidade de macrófitas do reservatório é composta por 133 espécies, pertencentes a 89 gêneros, distribuídos em 45 famílias, sendo 127 de Angiospermas, 5 de Samambaias e 1 de Hepática, neste trabalho é apresentado uma chave de identificação e descrições para as espécies presentes na área de estudo. Através das análises estatísticas observamos dois principais agrupamentos: o primeiro constituído de 4 bancos de macrófitas localizados no Braço Embu-Guaçu, caracterizados pela presença de macrófitas enraizadas com folhas flutuantes e submersas e com melhor qualidade de água e o segundo constituído de outros bancos com predomínio de espécies emergentes e flutuantes e água com maior carga de poluentes. A área de cobertura da espécie Polygonum ferrugineum diminuiu com elevação do nível da represa, enquanto a área de cobertura de macrófitas flutuantes livres (Pistia stratiotes e Salvinia herzogii) aumentou. Foi possível concluir que a Represa Guarapiranga possui uma elevada riqueza de macrófitas aquáticas, cuja composição específica é diferente entre os braços e corpo central.
The aim of this study was to investigate the composition and distribution of aquatic macrophytes in the Guarapiranga reservoir and contribute to the taxonomic knowledge of the species. Field work were performed monthly from June/2008 to May/2009, in 20 stands of macrophytes distributed throughout the reservoir. In each stand, the present species were recorded and collected and water temperature, pH, electric conductivity, dissolved oxygen and Secchi disk transparency were measured. Additionally, superficial water sample were collected for total phosphorus and chlorophyll \"a\" analysis in the laboratory. To investigate the distribution of macrophytes and its relationship with environmental variables, similarity and canonical correspondence analysis were performed. The aquatic macrophytes community of the reservoir was composed of 133 species belonging to 89 genera distributed in 45 families being 127 angiosperms, 5 ferns and 1 liverwort. This work presents an identification key and descriptions for the species present in study area. The statistical analysis showed a cluster of four macrophytes stands located in the branch Embu-Guaçu, characterized by the presence of rooted macrophytes with floating leaves and submerged and with a better quality of water.Another cluster was formed by the other groups of macrophyte stands that were dominate by floating and emergent species, where we observed higher load of pollutants in the water. The coverage area of the species Polygonum ferrugineum decreased with the increase in the water level of the reservoir, while the coverage of the free-floating species (Pistia stratiotes and Salvinia herzogii) increased. In conclusion, Guarapiranga has a great aquatic macrophytes species richness, with different specific composition in the branches and in the central body.

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Hsu, Tsung-Ta David. "Public Health Ecosystem Services and Potential Concerns of Freshwater Wetlands." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1439487401.

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Schaap, Andrew. "Deep roots : applying permaculture principles in order to mitigate flooding within the urban fabric of New Orleans." Manhattan, Kan. : Kansas State University, 2010. http://hdl.handle.net/2097/4098.

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35

Swanson, P., and n/a. "The implementation and initial performance of a wetland system constructed for urban runoff treatment in the Blue Mountains." University of Canberra. Applied Science, 1996. http://erl.canberra.edu.au./public/adt-AUC20061109.114929.

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French, Rachel. "Modelling urban runoff : volume and pollutant concentration of the Barker Inlet Wetland Catchment." Title page, abstract and contents only, 1999. http://web4.library.adelaide.edu.au/theses/09ENS/09ensf875.pdf.

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Bibliography :leaves 158-171. A monitoring program, funded by the South Australian government (through the former MFP Development Corporation), was established to monitor the quality and quantity of storm water entering and leaving the wetland. This study formed part of the funded program. Simple regression models were developed; and will assist in the monitoring of performance of the wetland to alleviate the pollutant load into the Barker Inlet.

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Schad, Aaron Neale. "Macroinvertebrate Colonization and Assemblages Associated with Aquatic Macrophytes in a Newly Created Urban Floodway Ecosystem, Dallas, Tx." Thesis, University of North Texas, 2013. https://digital.library.unt.edu/ark:/67531/metadc500077/.

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A study of macroinvertebrate colonization and assemblages, including secondary productivity of the familiar bluet damselfly or Enallagma civile Hagen (Odonata: Coenagrionidae), associated with the aquatic macrophytes Heteranthera dubia (Jacq.) MacMill. (water stargrass) and Potamogeton nodosus Poir. (American pondweed) was conducted at the Dallas Floodway Extension Trinity River Project (DFE) Lower Chain of Wetlands (LCOW), Dallas, TX, from September 2010 through November 2011. Macroinvertebrate abundance, taxa richness, Simpson's index of diversity, and Simpson's evenness from the two macrophytes and from three different wetland cells of varying construction completion dates, water sources, and native aquatic vegetation establishment were analyzed along with basic water quality metrics (temperature °C, pH, dissolved oxygen mg/L, and conductivity µs/cm). E. civile nymphs were separated into five developmental classes for secondary productivity estimations between macrophytes and wetland cell types. Mean annual secondary productivity in the DFE LCOW among two macrophytes of E. civile was 1392.90 ash-free dry weight mg/m²/yr, standing stock biomass was 136.77 AFDW mg/m2/yr, cohort production / biomass (P/B) ratio was calculated to be 4.30 / yr and the annual production / biomass (P/B) ratio was 10.18 /yr.

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Chen, Yuxiao, and 陳瑜瀟. "Zhuji wetland city: stormwater recycle." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B38297590.

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Parker, Nathaniel Ryan. "Assessing the effectiveness of water sensitive urban design in Southeast Queensland." Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/34119/1/Nathaniel_Parker_Thesis.pdf.

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Water Sensitive Urban Design (WSUD) systems have the potential mitigate the hydrologic disturbance and water quality concerns associated with stormwater runoff from urban development. In the last few years WSUD has been strongly promoted in South East Queensland (SEQ) and new developments are now required to use WSUD systems to manage stormwater runoff. However, there has been limited field evaluation of WSUD systems in SEQ and consequently knowledge of their effectiveness in the field, under storm events, is limited. The objective of this research project was to assess the effectiveness of WSUD systems installed in a residential development, under real storm events. To achieve this objective, a constructed wetland, bioretention swale and a bioretention basin were evaluated for their ability to improve the hydrologic and water quality characteristics of stormwater runoff from urban development. The monitoring focused on storm events, with sophisticated event monitoring stations measuring the inflow and outflow from WSUD systems. Data analysis undertaken confirmed that the constructed wetland, bioretention basin and bioretention swale improved the hydrologic characteristics by reducing peak flow. The bioretention systems, particularly the bioretention basin also reduced the runoff volume and frequency of flow, meeting key objectives of current urban stormwater management. The pollutant loads were reduced by the WSUD systems to above or just below the regional guidelines, showing significant reductions to TSS (70-85%), TN (40-50%) and TP (50%). The load reduction of NOx and PO4 3- by the bioretention basin was poor (<20%), whilst the constructed wetland effectively reduced the load of these pollutants in the outflow by approximately 90%. The primary reason for the load reduction in the wetland was due to a reduction in concentration in the outflow, showing efficient treatment of stormwater by the system. In contrast, the concentration of key pollutants exiting the bioretention basin were higher than the inflow. However, as the volume of stormwater exiting the bioretention basin was significantly lower than the inflow, a load reduction was still achieved. Calibrated MUSIC modelling showed that the bioretention basin, and in particular, the constructed wetland were undersized, with 34% and 62% of stormwater bypassing the treatment zones in the devices. Over the long term, a large proportion of runoff would not receive treatment, considerably reducing the effectiveness of the WSUD systems.

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Müller, Anaximandro Steckling. "Aplicabilidade de medidas não-estruturais no controle de cheias urbanas: estudo de caso Bacia Hidrográfica do Rio Cachoeira - Joinville - SC." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/3/3147/tde-05082011-145343/.

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Joinville, como grande parte das cidades brasileiras, desenvolveu-se ao longo dos vales dos diversos cursos dágua que drenam o município, sem que as questões envolvidas com a drenagem tivessem ocupado papel destacado no bojo das decisões sobre o planejamento do uso e ocupação do solo e da preservação dos escoamentos hídricos naturais. A reestruturação do sistema e de formas organizacionais da gestão determina os novos marcos da gestão urbana, tais como a necessidade do planejamento estratégico, colocando restrições ao crescimento não planejado, e a incorporação da questão ambiental nas políticas setoriais urbanas (habitação, abastecimento, saneamento, ordenação do espaço), através da observância de critérios ambientais que preservem os recursos estratégicos e protejam à saúde humana. As taxas elevadas e crescentes de urbanização observadas nas duas últimas décadas levaram a um agravamento de problemas urbanos, expresso pelo crescimento desordenado e fisicamente concentrado, ausência ou carência do planejamento e padrões atrasados na sua gestão. Logo, devem ser definidas regras de uso e ocupação que preservem aspectos vitais naturais e que possibilitem um sistema de transporte, abastecimento de água, esgotamento sanitário, tratamento, drenagem urbana e coleta, processamento e reciclagem dos resíduos, de modo a conciliar o desenvolvimento urbano com a sustentabilidade do espaço após a ocupação da população. O entendimento e a caracterização dos fenômenos relacionados aos eventos de inundação são de suma importância para criar uma ferramenta que possa auxiliar a proposição de medidas e a tomada de decisão para minimizar os danos causados pelas inundações. O presente trabalho buscou através de modelos hidrológicos e hidráulicos caracterizar os fenômenos envolvidos e relacioná-los a uma probabilidade de ocorrência. Essa caracterização resultou na delimitação de áreas de inundação. O controle das áreas de risco é fundamental para a gestão das áreas ribeirinhas, a partir dos dados de manchas de inundação. Foram estabelecidas diferentes zonas de risco que relacionaram urbanização e o risco da inundação. Para cada uma dessas zonas foram estabelecidas diretrizes que permitem a urbanização de forma adequada dessas regiões. Tendo em vista que inúmeras residências estão localizadas em zonas inundáveis, foram apresentadas medidas técnicas com o intuito de reduzir a vulnerabilidade da população presente nas áreas inundáveis. Essas deverão ser objeto de políticas de conscientização da população e deverão ser apresentadas e implementadas juntamente com a sociedade com o objetivo de minimizar os prejuízos causados pelas inundações. Esses estudos fornecem ferramentas para que a gestão pública possa agir de maneira adequada e estabelecer diretrizes para o uso e ocupação dessas áreas de risco.
Joinville, like most Brazilian cities, developed along the valleys of several streams that drain the city, without the issues involved with the drainage had occupied a prominent role in the wake of decisions on planning the use and occupancy soil and conservation of natural water flows. The restructuring of the system and the organizational forms of management sets new milestones in urban management, such as the need for strategic planning, placing restrictions on the unplanned growth and the incorporation of environmental issues in urban sectoral policies (housing, water supply, sanitation, ordering space), through the observance of environmental standards that protect strategic resources and protect human health. The high and increasing rates of urbanization observed in the last two decades have led to worsening urban problems, expressed by the uncontrolled growth and physically concentrated, absence or lack of planning and standards behind in their management. Therefore, rules must be defined for use and occupation to preserve natural and vital aspects that make it possible a transport system, water supply, sewage treatment, urban drainage and collection, processing and recycling of waste in order to reconcile urban development with the sustainability of the area after population\'s occupation. The understanding and characterization of the phenomena related to flood events are the utmost importance to create a tool that can help to propose measures and decision making to minimize flood damage. The present study sought through hydrologic and hydraulic models to characterize the phenomena involved and related them to a probability of occurrence, this characterization resulted in the delineation of flood hazard areas. The risks control areas is central to the management of riparian areas, data from the flood of patches of different areas were established venture that linked urbanization and flood risk. For each of these areas have been laid down guidelines that allow the urbanization of these areas appropriately. Considering that many residences are located in flood zones were presented technical measures aiming to reduce the vulnerability of this population in the wetlands, they shall be subject to political awareness in the population and should be presented and implemented together with the company in order to minimize flood damage. These studies provide the tools for public management to act appropriately and establish guidelines for the use and occupancy of these risk areas.

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Mangangka, Isri Ronald. "Role of hydraulic factors in constructed wetland and bioretention basin treatment performance." Thesis, Queensland University of Technology, 2013. https://eprints.qut.edu.au/63054/1/Isri%20Ronald_Mangangka_Thesis.pdf.

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This research project contributed to the in-depth understanding of the influence of hydrologic and hydraulic factors on the stormwater treatment performance of constructed wetlands and bioretention basins in the "real world". The project was based on the comprehensive monitoring of a Water Sensitive Urban Design treatment train in the field and underpinned by complex multivariate statistical analysis. The project outcomes revealed that the reduction in pollutant concentrations were consistent in the constructed wetland, but was highly variable in the bioretention basin to a range of influential factors. However, due to the significant amount retention within the filter media, all pollutant loadings were reduced in the bioretention basin.

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Calder, Jordan-Laine. "Weaving through the matrix: investigating the influence of urban land use on weaver bird movements into and out of Cape Town wetlands." Master's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/12816.

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Includes bibliographical references.
Urbanization, a fast growing and destructive human land use, causes local extinctions, biotic homogenization and fragmentation of natural habitats. Understanding how the nature of the urban matrix affects the species residing within a city’s fragmented habitats is an important founding component of urban conservation. This study investigated the influence that the urban matrix, as well as patch isolation, size and quality, had on weaver bird movement into and out of wetland sites in Cape Town, a growing city within a global biodiversity hotspot. Weaver bird movement data from 42 wetland sites were obtained through a long term mark - release - recapture project. Distance - based linear models revealed that site proximity was important as a predictor of weaver movement into and out of sites, while the site variables ( wetland size, bird abundance and weaver colony size) had limited and inconclusive influence. Once the variation explained by the proximity and site variables had been accounted for, the composition of the urban matrix and the presence of rivers as potential movement corridors (measured at three spatial scales) had little influence on weaver movement. The finding that proximity (or site isolation) influences weaver movement has important implications for maintaining current landscape connectivity. Habitat isolation, resulting from further habitat removal or destruction, could be expected to reduce movements of weavers, and potentially other species, among patches of favourable habitat. Weavers are robust, vagile birds that do well in the presence of humans and may not be highly sensitive to the nature of the urban matrix. Research into how other, less resilient and vagile species respond to the degree of urbanization in the matrix between wetlands would contribute further to our knowledge of urban biodiversity in this global biodiversity hotspot.

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Cardoso, Omar de Almeida. "Várzeas do Alto Tietê, as águas urbanas e a paisagem: conflitos, possibilidades e ações desejáveis para a qualificação dos espaços livres." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/16/16135/tde-29102015-145337/.

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O presente trabalho tem como objetivo contribuir para um debate sobre a possibilidade de intervenções ou ações para a qualificação urbano-paisagístico-ambiental em áreas de fundo de vale urbanas, um tema relativamente emergente no Brasil, e de relevante interesse e importância em âmbito científico, técnico e legal. Realizada entre os anos de 2011 e 2015, a pesquisa de referência esteve alocada na área de concentração \"Paisagem e Ambiente\", dentro da linha de pesquisa \"Sistemas da Paisagem\", do Programa de Pós-Graduação em Arquitetura e Urbanismo da Faculdade de Arquitetura e Urbanismo da Universidade de São Paulo (FAUUSP). O objeto do estudo são as águas urbanas, definidas aqui como os corpos d\'água integrantes do meio ou da paisagem, que compõem um sistema urbano de espaços livres, e que devem ser considerados como espaços da vida cotidiana, tendo suas orlas aproveitadas para fins urbanos diversificados, e não apenas para suporte de infraestruturas como sistema viário ou drenagem. Fruto de uma relação perversa e conflitante entre a sociedade e o meio, as águas urbanas foram, e ainda vêm sendo vistas, no início deste século XXI, de forma excludente do cotidiano urbano, mesmo após a imposição de legislações específicas e de programas públicos. Os impasses para uma efetiva gestão pública dos corpos d\'água são muitos, e isso se dá principalmente devido à não existência de políticas e/ou ações integradas para sua conservação e manejo. Mesmo assim, existe uma realidade possível de ser alcançada em termos de qualificação ou requalificação das águas urbanas, principalmente em regiões densamente ocupadas, como as metrópoles brasileiras. Nesses grandes centros urbanos o desafio está na busca de um equilíbrio hídrico, cuja solução de conflitos passa obrigatoriamente pelo planejamento urbano-paisagístico-ambiental sobre o território, tanto na micro e como na macroescala, e conforme os preceitos do planejamento / arquitetura da paisagem. Para tanto, faz-se necessário, de preferência, o uso das tecnologias disponíveis, mediante o consenso entre os grupos e/ou sociedades envolvidas, enfim, através de uma agenda conjunta e continuada, que trata dos atuais conflitos, prevenindo e evitando novos conflitos e problemas. O trabalho traz como recorte a área drenada pela Bacia Hidrográfica do Alto Tietê (BHAT), uma das bacias mais complexas do País no que se refere à gestão ambiental, principalmente por decorrência das profundas alterações em suas várzeas, causadas por intervenções hidráulicas, mas também pelo modelo de urbanização adotado e pela ocupação extensiva do solo urbano. Entretanto, apesar de seus contrastes e paradoxos, a região apresenta ainda reais possibilidades de utilização de seus espaços livres na metrópole contemporânea, como meio de viabilização de uma requalificação funcional e ambiental, considerando-se, os sérios problemas decorrentes do estado atual de degradação da paisagem e do meio ambiente. Um exemplo são as várzeas da sub-região Cabeceiras, a jusante da Capital, localizada na porção leste da Região Metropolitana de São Paulo (RMSP): uma área bastante sensível, com grande parte de seus limites incluídos em Área de Proteção aos Mananciais (incluindo áreas destinadas à reserva de água para o abastecimento público), e com grande parte de sua várzea ainda preservada (incluindo alguns trechos com mata nativa), e que tem na ocupação urbana (vetor de crescimento), o seu principal e grande conflito.
The present thesis aims to debate the possibility of actions as well as interventions in the current Brazilian legislation policy for sustainable urban landscape planning in urban lands alongside Tietê River, located in the state of São Paulo, Brazil. This theme, relatively emergent in Brazil, is considered of great importance in the scientific, technical, and legal contexts. This study is part of the \"Landscape System\" academic research conducted by the University of São Paulo (USP), with focus on \"Landscape and Environment\", performed by the Architecture and Urbanism Post-Baccalaureate Program from years 2011 to 2015. The main scope of this research is to consider sustainable utilization and development of open spaces alongside urban waters, focusing on multiple benefits within the urban areas, and improving population\'s quality of life. The current role played by open spaces has been mostly to support drainage and transport systems infrastructure. However, such open spaces should be considered part of everyday life, together with becoming an accessible asset to the actual population and the future generations. In spite of the development of public programs during the 21st century, in conjunction with existing legislation, urban waters have not being considered part of everyday life. The public management of urban waters lacks efficiency, especially due to the non-existence of proper policies as well as effective integrated actions for its conservation and administration. Nevertheless, it is feasible to redefine the qualification/requalification of open spaces alongside urban waters, especially in overpopulated areas, like the Brazilian metropolis. The purpose of this research is to explore the drained area by Alto Tietê River basin, one of the most complex river basins in Brazil in terms of sustainable management, particularly due to the dramatic changes in its surrounding lands caused by hydraulic interventions, unplanned urban expansion, and deficient urban model. Despite all the adversities and paradoxes, this region still remains a possible zone for urban open spaces development. This could be a way not only to improve environmental sustainability, but also to benefit the population with long term environment protection, and with the implementation of sensible public facilities. In order to achieve this new reality, an integrated approach regarding the planning, monitoring, designing, and maintaining these projects are imperative, in addition to the optimization of the proper policies.

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Millot, Yoann. "Use of alternative matrix materials and configurations for optimizing nitrogen removal in constructed wetlands." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEI021/document.

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L’assainissement d’effluents résiduaires urbains par filtres plantés de roseaux (FPR) rencontre, depuis plus de trois décennies, un engouement croissant en raison de ses remarquables performances de traitement ainsi que de considérations technico-économiques et écologiques. Néanmoins, des objectifs de traitement de plus en plus contraignants, ainsi qu’un marché de plus en plus concurrentiel, amènent la nécessité d’une meilleure connaissance des processus afin d’en optimiser la conception en fonction du contexte. Une attention toute particulière a été portée au traitement de l’azote, au cours de cette étude, en raison de l’aspect particulièrement contraignant de son élimination. Ces travaux se sont articulés autour de trois axes principaux permettant l’évaluation des principaux mécanismes d’élimination de l’azote (nitrification, dénitrification et adsorption, respectivement). Un premier volet, conduit sur unités pilotes alimentées en effluents domestiques réels, s’est attaché à identifier l’impact respectif de divers critères de dimensionnement et opérationnels (profondeur de filtration, surface de filtration, charges hydrauliques et organiques) afin de proposer des consignes de conception adaptées aux objectifs de traitement sur l’azote ammoniacal ainsi que la matière organique et la pollution particulaire. Une seconde partie de l’étude, mené à échelle pilote à partir d’effluents semi-synthétiques, s’est quant à elle focalisée sur le processus de dénitrification afin de mettre en exergue les critères majeurs (composition des effluents, paramètres de conception et fonctionnement) pour l’atteinte de performances poussées sur le traitement des nitrates. Enfin, un dernier axe de recherche, effectué en laboratoire en colonne, a visé à évaluer l’effet de l’adsorption d’ammonium sur matériaux filtrants réactifs (zéolithe) en vue d’optimiser par la suite le temps de rétention de cette espèce au regard des cinétiques de dégradation biologique. Une synthèse des connaissances acquises au cours de cette étude a donné lieu à des conseils de conception ainsi qu’à des recommandations pour d’éventuelles études complémentaires
The treatment of domestic wastewater by constructed wetlands (CWs) meets, from more than three decades, an increasing interest because of its high treatment efficiency as well as technological, economic and ecological issues. However, with treatment objectives that are growing ever stricter and an increasingly competitive market, fine knowledge of removal processes is required in order to optimize design in regards with context. A particular attention was paid to nitrogen removal, through this study, because of its particularly coercive dimension in treatment process. This work is partitioned in three axes which enable the assessment of the main mechanisms ensuring nitrogen removal (nitrification, denitrification and sorption, respectively). A first part, conducted in pilot-scaled units fed in real domestic wastewater, aimed at identifying the respective effects of various design and operational parameters (filtration height, filtration area, hydraulic and organic loads) in order to provide design recommendations for an efficient removal of ammonium as well as organic matter and suspended solids. A second part of this work, carried out in pilot-scaled units fed with semi-synthetic wastewater, focused on denitrification process in order to highlight driving parameters (influent composition, design and operational parameters) of full nitrate removal. Last but not least, a third research axis, conducted in column-scaled units, assessed the ammonium adsorption onto reactive material (i.e. zeolite) in order to optimize the retention time of ammonium within the system in regards with nitrification kinetic. These results were then summarized in order to provide design guidelines as well as recommend further complementary experiments

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Banerjee, Srestha. "An evaluation of the political economy of urban ecological sustainability in Indian cities in a globalizing era a perspective from the East Kolkata Wetlands /." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 227 p, 2010. http://proquest.umi.com/pqdweb?did=1992441161&sid=5&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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Mahoney, J. Liam. "Responding to shock: a collaborative process for the St. Roch neighborhood." Kansas State University, 2011. http://hdl.handle.net/2097/9161.

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Master of Landscape Architecture
Department of Landscape Architecture/Regional and Community Planning
Lee R. Skabelund
Hurricane Katrina displaced many New Orleans residents, leaving in its wake tens of thousands of vacant lots and buildings. In 2010, estimates show that over 57,000 properties lay empty in the city, especially in the poorer neighborhoods. These properties are not contributing to the fabric of the city; in most places, they are a sign of defeat, an eyesore, or a haven for crime. The neighborhood of St. Roch is experiencing the negative effects of these properties day in and day out and from year to year. Almost a quarter of the lots are vacant in the St. Roch neighborhood, leading to crime and creating a nuisance and a blemish on the community. Coupled with the lack of ownership there is an ailing stormwater management infrastructure leading to areas of flooding after routine storms. In addition to these concerns, there is a lack of fresh, inexpensive and accessible food throughout the area. Although St. Roch’s vacant lots have a negative effect on the community, they present a tremendous opportunity. Their dispersal around the neighborhood presents the opportunity to connect them to churches, schools, retail outlets, as well as providing other uses and services to the neighborhood. The thoughtful design of these locations will demonstrate a site-sensitive approach to the local ecology, culture, and economy of the neighborhood. Such design includes the community throughout the entire lifecycle of each site from its planning phase to the end of its use. The primary goal throughout the planning and design process is to foster stewardship for both the landscape and the community as a whole by means of collaborative planning, direct interaction with each site during implementation, and the observation and monitoring of crucial processes throughout a site’s lifecycle. The intent of this project is to apply a participatory framework to the site design process in order to rejuvenate critical areas of the St. Roch neighborhood. This project seeks to demonstrate the need for a collaborative process while allowing for a balance between the experts who help design each site and the community members who take ownership of the renewed parcels.

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Gunsch, Marilyn S. "The Effect of Wetland Size and Surrounding Land Use on Wetland Quality along an Urbanization Gradient in the Rocky River Watershed." Cleveland State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=csu1221428755.

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Murphy, Sarah Elizabeth. "An investigation into the treatment efficiency of a primary pond in the Barker Inlet Stormwater Wetland System, South Australia /." Title page, table of contents and abstract only, 1999. http://web4.library.adelaide.edu.au/theses/09ENS/09ensm978.pdf.

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Thesis (M.Eng.Sc.)--University of Adelaide, Dept. of Civil and Environmental Engineering, 2000?
Corrigenda pasted onto front end-paper. The CD contains Excel spreadsheets containing data collected. Bibliography: leaves 209-222.

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Jönsson, Robert. "Mikroplast i dagvatten och spillvatten : Avskiljning i dagvattendammar och anlagda våtmarker." Thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-308455.

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Mikroplast, här definierat som plastobjekt mindre än 5 mm, befaras kunna göra stor skada på vattenlevande djur. Fram tills idag har studier av mikroplastreduktion främst utförts i kommunala avloppsreningsverk där mycket av plasten avskiljs. De stora spillvattenflödena gör ändå reningsverken till betydande utsläppspunkter av mikroplast till sjöar och hav. Information har hittills till stor del saknats om mikroplastförekomst i dagvatten, vilket ofta släpps ut orenat och i större volymer än spillvatten. Förekomst av mikroplast >20 µm (>0,02 mm) har undersökts för tre tätorters dagvatten samt för två avloppsreningsverks utloppsvatten. Avskiljning av mikroplast har undersökts för två spillvattenvåtmarker och två dagvattendammar. Båda anläggningstyper är relativt billiga och effektiva när det gäller reduktion av tungmetaller och övergödande näringsämnen. Örsundsbro våtmark och våtmark Alhagen tar båda emot behandlat spillvatten från kommunala avloppsreningsverk. I våtmark Alhagen finns även ett inlopp för dagvatten från Nynäshamn. Till dagvattenanläggningen Korsängens vattenpark leds en stor del av Enköpings dagvatten, medan Tibbledammen tar emot det dagvatten som kommer från Kungsängen i Upplands-Bro kommun. Vatten från anläggningarnas inlopp och utlopp, samt från två punkter inuti våtmark Alhagen har pumpats genom 20 µm-filter och 300 µm-filter. Provtagningen har kompletterats med insamling av mindre vattenvolymer som har filtrerats på laboratorium. Kvantifiering av mikroplast har gjorts med hjälp av stereomikroskop och vanligt förekommande objekts material har undersökts genom FTIR-spektroskopi. I våtmark Alhagens inkommande spillvatten var mikroplastkoncentrationen 4 objekt/liter, vilket liknar de koncentrationer andra svenska studier uppmätt i behandlat spillvatten. I inkommande vatten till Örsundsbro våtmark var koncentrationen över 950 objekt/liter, långt över vad andra svenska studier uppmätt i helt obehandlat spillvatten. I dagvatteninloppen var mikroplastinnehållet 5,4–10 objekt/liter, vilket indikerar på att mikroplatsutsläpp via dagvatten kan befaras vara minst lika stora som via spillvatten. I alla anläggningars inkommande vatten, förutom i våtmark Alhagens dagvatteninlopp, uppmättes höga koncentrationer av rödfärgade partiklar. Partiklarna kan vara av plast eller av annat okänt material och är till utseendet relativt lika de som andra studier påträffat i svenska kustvatten. Svarta partiklar påträffades i alla inflöden och ofta i mer än 100 gånger högre halter än de för mikroplast och röda partiklar, förutom i våtmark Alhagens spillvatteninlopp där de röda partiklarna var något fler. Partiklarna tros kunna vara däck- och vägrester eller förbränningspartiklar. Alla anläggningar visade på en tydlig avskiljning, ofta 90-100 %, för mikroplast, svarta och röda partiklar >20 µm. Till följd av resultatet samt anläggningarnas variation i ålder, storlek och utformning bör dagvattendammar och anlagda våtmarker generellt kunna förväntas fungera som effektiva barriärer mot spridning av mikroplast, svarta partiklar och röda partiklar.
Microplastics (MPs), here defined as plastic objects smaller than 5 mm, are suspected to cause great harm to fish when released into lakes and oceans. Studies of MP retention have until recently mainly been done for sewage treatment plants (STPs), where much of the plastics are shown to be retained in the sludge. However, due to large water flows in STPs, they can be seen as significant points for the spreading of MPs to recipient waters. Today there isn’t much information to be found about MP contents in stormwater. Stormwater is often released untreated and depending on climate it can be released in greater volumes than sewage water from urban areas. The occurrence of MPs >20 µm (>0.02 mm) has been studied in two STP effluents, and in stormwater from three urban catchments. The retention of MPs has been studied for two stormwater ponds, and for two free water surface wetlands constructed for tertiary treatment of sewage. Wetland Alhagen and Örsundsbro wetland both receive the effluents of secondary STPs. In wetland Alhagen there is also a stormwater inlet from the town of Nynäshamn. To the stormwater pond Korsängens vattenpark, stormwater is lead from the town of Enköping, while the stormwater pond Tibbledammen receives stormwater from Kungsängen in Upplands-Bro municipality. Influents and effluents from the facilities, as well as water from two points within wetland Alhagen was pumped through 20 µm and 300 µm filters. In addition, water from every sampling point was collected in minor volumes for later filtration carried out in a laboratory. Quantification was done with microscopy and a number of objects were analyzed with FTIR spectroscopy for material determination. In wetland Alhagen, the sewage inlet contained 4 MPs/liter, which is similar to results for STP effluents in other Swedish studies. In Örsundsbro wetland, the incoming water contained more than 950 MPs/liter, far greater than what other studies have shown for untreated sewage. The MP concentrations in the three stormwater inlets were between 5.4-10 MPs/liter. This indicates that untreated stormwater could be seen as a pathway for MPs at least as big as treated sewage. In almost all inlets, characteristic red particles were found in great numbers and in sizes of 20-300 µm. Analysis of some of the red particles indicated that they contained plastic while others were of unknown materials. The particles had a similar appearance to red particles commonly found in Swedish coastal waters. Black particles, a kind of microscopic particles that may originate in tyre wear (i.e. MPs) or combustion, was also found in large quantities. Except for in the main influents of wetland Alhagen, where the number of red particles was slightly higher, the black particles were always found in far greater numbers than both regular MPs and red particles (often >100x greater). The retention of MPs, black particles and red particles >20 µm was high in all the facilities, often around 90-100 percent. Based on these results and the variation of size, design and year of construction, stormwater ponds and constructed free water surface wetlands can be seen as effective barriers against the spreading of MPs.

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50

Silva, Roges Roveda Vinhola da. "Avifauna de áreas úmidas no município de Caxias do Sul, Rio Grande do Sul." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2007. http://hdl.handle.net/10183/13591.

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Abstract:

Estudos sobre as comunidades de aves em áreas úmidas evidenciam a importância destas áreas para a avifauna. Muitos estudos destacam a importância da teoria de biogeografia de ilhas e da heterogeneidade ambiental sobre a estrutura da comunidade de aves. O presente estudo teve por objetivo caracterizar a estrutura da comunidade de aves e verificar a influência de variáveis da paisagem e de aspectos antrópicos em seis áreas úmidas e seu entorno em Caxias do Sul, Rio Grande do Sul, de setembro de 2005 a março de 2006. As aves nas áreas úmidas foram quantificadas através de varreduras e as aves em seu entorno através da contagem por pontos de escuta na primavera e verão. Os aspectos antrópicos e dados biológicos foram observados em campo a cada expedição. Para análise da estrutura avifaunística foram avaliadas a riqueza observada, estimativa da riqueza, número cumulativo de espécies, freqüência de ocorrência, composição, hábito alimentar e diversidade. A significância da diversidade foi avaliada através da aplicação do teste t. O conjunto das áreas foi analisado através de análise de agrupamento. As variáveis da paisagem, heterogeneidade ambiental e os aspectos antrópicos foram avaliados através de análise de correspondência. Os resultados indicaram que a estrutura da comunidade de aves dos lagos difere da comunidade de aves do entorno. As áreas maiores não apresentaram maior riqueza e diversidade, demonstrando a influência de outros fatores sobre a comunidade. As análises de correspondência demonstraram que a maioria das espécies foram influenciadas por variáveis tanto da paisagem como da heterogeneidade ambiental e pelos aspectos antrópicos. As comunidades de aves em áreas úmidas foram mais influenciadas pela vegetação no entorno dos lagos e sobre a lâmina d’ água. Algumas das áreas úmidas ocupadas por Passeriformes, demonstrando a importância das áreas também para espécies não consideradas aquáticas. Os hábitats florestal, campestre e de capoeira comprovaram a influência sobre a ocorrência da avifauna. Este estudo reafirma que a teoria de biogeografia de ilhas por si só não explica a riqueza e presença das espécies. A heterogeneidade ambiental deve ser analisada cuidadosamente para não tender a homogeneização. Ocorre também, uma necessidade de revisão no conceito sobre as aves aquáticas, visto que outras espécies também ocuparam as áreas úmidas. Estes resultados servem de subsídios para o manejo e conservação das áreas úmidas em ambientes urbanos.
Studies on the bird communities of wetlands attest the importance of such áreas to avifauna. Several studies point out the importance of island biogeography theory and environmental heterogeneity upon the structure of bird communities. This study aimed to characterize the structure of the bird community and check the influence of landscape variables and antropic aspects within six areas of lakes and their surroundings in Caxias do Sul, Rio Grande do Sul, from september 2005 to march 2006 (spring and summer). The number of birds at the lakes was estimated through counting flocks and of those in the surroundings through point counts. Anthropic aspects and biological data were evaluated in the field during each expedition. The analysis of the avifauna structure included observed richness, estimated richness, cumulative number of species, frequency of occurrence, composition, feeding habits and diversity. The diversity significance was evaluated using t test. Cluster analysis was used to examine the areas altogether. Landscape variables , environnmental heterogeneity and anthropic aspects were evaluated by correspondence analysis. The results revealed that the bird community of the lakes has a different structure from that of surroundings. Larger areas did not have greater richness and diversity, which points out the influence of other factors upon the community. The correspondence analysis showed that most species were influenced by both landscape variables, such as environmental heterogeneity and anthropic aspects. Bird communities in the humid areas were most influenced by the vegetation that encircled the lakes and by the aquatic vegetation. Some of wetlands were used by passeriforms, which reveals the importance of such areas also to species not considered as aquatic. The influence of forest, field and bush habitats on the occurrence of birds was confirmed. This study reinforces that the island biogeography theory alone cannot explain the richness and presence of species. The environmental heterogeneity should be kept, avoid the landscape homogenization. Also, there is a need to review the concept of aquatic birds since other kind of species used the humid areas. These results are a souce to management and conservation of wetlands within urban environments.

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Dissertations / Theses on the topic 'Urban wetlands'

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