Dissertations / Theses: 'Pond management'

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Hill, Matthew J. "Aquatic macroinvertebrate biodiversity of lowland rural and urban ponds in Leicestershire." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/17866.

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Ponds are common and abundant features in nearly all landscapes typical of European lowland landscapes yet research on freshwater biodiversity has traditionally focussed on larger waterbodies such as lakes and rivers. This has led to an increased need to understand and quantify the biodiversity associated with pond habitats to better inform the active conservation and management of these small waterbodies. This thesis examines the aquatic macroinvertebrate biodiversity (alpha, beta and gamma) and conservation value of 95 ponds in Leicestershire, UK, across a variety of urban and rural landscape types and at a range of spatial scales. In addition, the relative importance of local (physicochemical and biological) and spatial (connectivity) variables in structuring macroinvertebrate communities within ponds is investigated. At a regional scale, the greatest macroinvertebrate biodiversity and conservation value was recorded within meadow ponds compared to urban, agricultural and forest ponds. Spatially, ponds were highly physically and biologically heterogeneous. Temporally (seasonally), invertebrate communities were most dissimilar in meadow and agricultural ponds but assemblages were similar in urban and forest ponds. In urban landscapes, park ponds supported a greater diversity of invertebrates than other urban or garden ponds and typically had a greater conservation value. Garden ponds were the most taxon poor of those investigated. Perennial floodplain meadow ponds supported a greater biodiversity of invertebrates compared to ephemeral meadow ponds although conservation value was similar. Despite regular inundation from the River Soar, ephemeral ponds supported distinct communities compared to perennial meadow ponds. Aquatic macrophytes supported a higher diversity of taxa than other pond mesohabitats across all landscapes studied. Physicochemical factors were identified to be the dominant influence on macroinvertebrate assemblages although, a combination of local and spatial factors best explained the variation in community composition at a regional scale and for meadow ponds. Spatial factors were not identified to significantly influence urban pond communities. This study highlights the ecological importance and conservation value of ponds in rural and anthropogenically disturbed landscapes. Recognition of the significant contribution of ponds to freshwater biodiversity at regional and landscape scales is important for future conservation of pond habitats and will help focus and direct conservation strategies to where they are needed most.

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Chmilar, Jennifer Andrea. "Ancient Maya Water Management: Archaeological Investigations at Turtle Pond, Northwestern Belize." Cincinnati, Ohio : University of Cincinnati, 2005. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1121358311.

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Betts, Anthony Thomas. "Assessment of a Countywide Stormwater Pond Improvement Project: Impacts of the Hillsborough County Adopt-A-Pond Program." Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3009.

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Comparative research was conducted to assess the environmental impacts of the Adopt-a-Pond program, which operates throughout Hillsborough County, Florida. The Adopt-a-Pond program was established in 1992 and designed to address nonpoint pollution through outreach and stormwater pond enhancement. However, the program had never been thoroughly and scientifically evaluated. Therefore, assessments of water quality and vegetative characteristics were made at ninety Adopt-a-Pond participants and eleven control ponds to explore the potential impacts of the program on measurable environmental parameters. Statistical analysis of the results failed to demonstrate any statistically significant environmental improvements associated with the Adopt-a-Pond program, and measures of program activity did not illustrate a consistently positive relationship. These results indicate a need to readdress the policies and implementation of the program. Poor compliance by program volunteers, evident by the limited span of group participation (mean = 2.5 years) and relatively low percentage of actively involved residents, is the most likely culprit for the unremarkable improvements in pond quality, as pond enhancement techniques are firmly established in the literature. Overall, these conclusions underline the need for an integrated evaluation component in policymaking and an adaptive management approach to environmental management. A more detailed analysis is warranted to provide time series data, which examines ponds both before and after entry to the program and after implementing landmark improvement measures. In the end, the results of the study have provided a better understanding of the AAP and other similar restoration programs, and hopes to allow for enhancement of AAP program restoration practices.

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Ansah, Yaw Boamah. "Enhancing Profitability of Pond Aquaculture in Ghana through Resource Management and Environmental Best Management Practices." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/51122.

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The accelerating pace of growth of aquaculture in sub-Saharan Africa has received much positive appraisal because of the potential of the industry to contribute to economic development and food security by providing jobs and animal protein. Adoption of best management practices (BMPs) holds the potential to ameliorate the related environmental impacts of aquaculture, such as in the amounts of nutrients and sediment that will enter natural water bodies from earthen pond effluents. The goals of this study were to characterize adoption of aquaculture BMPs on small-scale, pond-based farms in Ghana, and to assess selected economic, social, and environmental outcomes of BMP adoption. Two BMPs: 1) water reuse, and 2) commercial floating feeds, were investigated for adoption by pond-based fish farmers in Ghana. I conducted my study in Ghana using on-farm experiments involving intensive monitoring of water quality and growth of Nile tilapia (Oreochromis niloticus) over two production cycles. Additionally, I administered a baseline survey to 393 (and a follow-up survey to 160) fish farmers. I determined the best model for modelling farmed Nile tilapia growth with multi-model inference based on Akaike information criterion (AIC), the profitability of adopting BMPs with stochastic enterprise budgets and, social welfare impact with the Economic-Surplus model. I used a Markov model to predict the equilibrium rate of adoption of the two BMPs and determined the impact of BMP adoption on the reduction of pollutant loading with the Minimum-Data method of the Tradeoffs Analysis (TOA-MD). My results showed that the logistic model is a better alternative to the von Bertalanffy model for modelling the growth of Oreochromis niloticus under pond aquaculture conditions. There were no significant differences in fish weight between the water re-use BMP and the use of new water. Adoption of the commercial floating feed BMP resulted in a 100% increase in fish final weight and yield, and in higher profitability, compared to the sinking feed type. Probability of making a profit was highest (72%) in the scenario with commercial feed and self-financing. Net present values (NPV) of about US$ 11 million and US$ 375 million could be obtained from the adoption of commercial floating feed and Genetically-Improved Farm Tilapia (GIFT) strain, respectively, in Ghana. Hence, any innovation that has a significant impact on fish yield also will have a significant impact on mean NPV and social welfare. However, I identified a number of potential negative ecological and genetic impacts exist from introducing the GIFT strain into Africa from Asia. Although considered low-intensity production systems, nutrients and solids in study ponds were found to be higher than levels expected in intensive culture ponds by wide margins. Pond water quality was significantly higher with commercial floating feed. The water-reuse BMP also prevented pollutants from leaving ponds altogether for the number of cycles for which pond water was reused, especially if associated BMPs such as rainfall capture and avoidance of water exchange are observed. Significant reductions in the loading of all water quality variables (nitrogen, phosphorus, solids, and BOD5) could be achieved with the adoption of the recommended feed type in Ghana. Adoption of the water reuse BMP has the potential to cause pollution reductions of 200% - 3,200% above that from the floating feed BMP. The strongest influence on the combined adoption of these BMPs were from : farmer's awareness of the feed BMP, perceived necessity and relative profitability of the water reuse BMP, and farmer's years of experience. A combination of central media (workshops), demonstrations, and lateral diffusion was found to be the most effective channel for disseminating these BMPs. Maximum adoption rate of the feed BMPs was estimated to be 38% - 58%. Also, US$ 6,000/year and US$12,000/year need to be paid per 0.6 ha pond surface area to push adoption of the feed BMP to 50% and 70%, respectively. Hence, to ensure the successful adoption of aquaculture BMPs, I recommend that regular well-planned workshops be organized to create awareness and a conducive atmosphere to target farmers at multiple stages of the innovation decision process. Incentives and effective dissemination will encourage the adoption of these and other environmental BMPs. Feed costs need to be lowered in order to encourage the adoption of commercial floating feed in Ghana. Future analyses could quantify the differences in production costs between using the two water types, to reveal the possible higher relative profitability of pond water reuse over draining ponds after each production cycle. Also, African governments are advised to commission rigorous baseline and ecological risk analyses before adoption of the GIFT strain. Improvements in management practices and infrastructure could increase the yield and profitability of the local strains even if genetically-improved strains are not introduced.
Ph. D.

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Schonrock, April Elizabeth. "An Internet survey of private pond owners and managers in Texas." Texas A&M University, 2005. http://hdl.handle.net/1969.1/2650.

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This study was designed to integrate a mailing list-based survey with an internetbased presentation/response in order to take into account the trend toward selfadministration that is evident in everyday interactions with automated services that have taken the place of personal interactions. A random sample of 2,999 was taken from applicants for Triploid Grass Carp Permits from the Texas Parks and Wildlife Department. A forty-nine question survey was constructed containing five sections: general pond characteristics, physical pond characteristics, aquatic vegetation, fish and other wildlife, and management goals. The primary emphasis of this study was to determine what specific problems Texas pond owners faced, how widely these problems occurred, and where pond owners got the information they used to deal with pond management problems. A secondary emphasis of the project was to examine the potential presented by the Internet for use in this type of information gathering and distribution for Texas Cooperative Extension. An overall response rate of 21.3% (excluding non-deliverables and unusable submitted surveys) was obtained. Summary statistics for each question were calculated and then compared in order to gain a clearer picture of the pond management practices employed by Texas pond owners. These results indicated some initial discrepancies between pond owners?? management practices and current management recommendations, most dramatically where aquatic vegetation was concerned. The internet-based survey methodology worked effectively to lower the cost of distribution and the workload of data entry when compared to the mail survey. These benefits outweighed the disadvantages caused by survey error with the new methodology.

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Kränzlin, Irène. "Pond management in rural Bangladesh : system changes, problems and prospects, and implications for sustainable development /." Basel : Wepf, 2000. http://www.gbv.de/dms/bs/toc/321459563.pdf.

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Hollinshead, James Michael. "Investigating the great crested newt landscape in a pond rich environment : developing a landscape scale management perspective." Thesis, Liverpool John Moores University, 2011. http://researchonline.ljmu.ac.uk/6167/.

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This thesis investigated graph theoretic analysis of connectivity and habitat availability for landscape scale management of Triturus cristatus, the Great Crested Newt. The ecological foundations of wider landscape management concepts and knowledge base on T. cristatus' habitat requirements, dispersal and migration were explored. Species presence, and aquatic and terrestrial habitat on the Cholmondeley Estate, Malpas, Cheshire, UK was mapped and land cover characterized for suitability and traversibility by T. cristatus. Habitat area available and accessible from ponds were identified. Analysis and modelling of pondscape connectivity using Probability of Connectivity (PC) and related indices, was carried out using Euclidean and Cost Weighted Distance and pond clustering at ecologically relevant scales was examined. Association or correlation of presence with proximity to breeding ponds, pond cluster size, proximity and available quantity of terrestrial habitat, proximity to roads and moving water, and connectivity of breeding ponds were examined at Cost Weighted and Euclidean distances. Connectivity, (PC index), pond count in clusters at 250 and 500m thresholds of connectivity, and proximity to core habitat (broad leaved woodland and rough grassland) using Cost Weighted distances were positively associated with breeding presence. Road proximity and density, proximity of core habitat at Euclidean distances and mean inter-pond distance were not significantly associated with breeding presence. Proximity to moving water was negatively associated with breeding presence. Resistance to movement of various land cover types has important implications for habitat availability and connectivity, , / and important questions are raised in terms of "rule of thumb" guidelines for estimation of connectivity between pond populations and habitat availability around breeding ponds. Graph analysis was used to identify priority areas for maintenance of landscape level connectivity, and enhancement of habitat connectivity and availability on the local population scale, with prioritization of pond creation/protection sites against their contribution to connectivity and habitat I availability, examining various scenarios.

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Nerhus, Barry S. Jr. "The movements, habitat use, and population assessment of western pond turtles (Actinemys marmorata) in a Southern California seasonal wetland." Thesis, California State University, Long Beach, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10105256.

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This study investigates the population dynamics, movements, and habitat use of a population of western pond turtles in Orange County, California from 2008-2012 using radio telemetry and mark-recapture data. Western pond turtles have been thought to be declining throughout their range. However, few studies have documented their status in southern California, where urbanization has changed the landscape drastically in recent decades. I individually marked 236 pond turtles using hoop-net funnel traps and estimated the population size at 308 individuals, which is the largest estimate reported in southern California. Mean capture per unit effort was 5.03±0.87. Mean female carapace length (CL) (142±14mm) was not significantly larger than males (139±14 mm). I also documented 20 nest and 9 estivation locations. Mean distances included 176 ±130.80 meters (m) and 91±58.6 m. These data identify the population demography, which can be a metric of population stability. Other known populations need to be estimated to determine their regional status.

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Marsalek, Peter Michael. "Special characteristics of an on-stream stormwater management pond, winter regime and accumulation of sediment and associated contaminants." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq22360.pdf.

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Ouedraogo, Faissal Romaric. "Impact of Sludge Layer Geometry on the Hydraulic Performance of a Waste Stabilization Pond." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6344.

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Improving the hydraulic performance of waste stabilization ponds (WSPs) is an important management strategy to not only ensure protection of public health and the environment, but also to maximize the potential reuse of valuable resources found in the treated effluent. To reuse effluent from WSPs, a better understanding of the factors that impact the hydraulic performance of the system is needed. One major factor determining the hydraulic performance of a WSP is sludge accumulation, which alters the volume of the pond. In this study, computational fluid dynamics (CFD) analysis was applied to investigate the impact of sludge layer geometry on hydraulic performance of a facultative pond, typically used in many small communities throughout the developing world. Four waste stabilization pond cases with different sludge volumes and distributions were investigated. Results indicate that sludge distribution and volume have a significant impact on wastewater treatment efficiency and capacity. Although treatment capacity is reduced with accumulation of sludge, the latter may induce a baffling effect which causes the flow to behave closer to that of plug flow reactor and thus increase treatment efficiency. In addition to sludge accumulation and distribution, the impact of water surface level is also investigated through two additional cases. Findings show that an increase in water level while keeping a constant flow rate can result in a significant decrease in the hydraulic performance by reducing the sludge baffling effect, suggesting a careful monitoring of sludge accumulation and water surface level in WSP systems.

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Deepa, K. G. "Occurrence of ectocommensal ciliates on Metapenaeus dobsoni (MIERS) in relation to water quality parameters in pond ecosystem at Vypeen." Thesis, Central Marine Fisheries Research Institute, 1997. http://eprints.cmfri.org.in/11050/2/Deepa%20K.G..pdf.

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Fishery sector has a place of pride in the national economy of India. Shrimps are the single item in the basket of marine products with universal taste-remain the backbone of Indian marine product export. Due to the declining trend of prawn catches from the sea, brackish water and fresh water prawn farming has immense scope to fulfill the growing demands of the population. The culture practices are mostly restricted to Penaeus sp. obviously because of certain special qualities attributed to it. However, in traditional prawn culture, practised in coastal waters, prawns other than Penaeus sp. also enter the culture system and grow. Thus about 60-80% o f the catch is contributed by Metapenaeus dobsoni and smaller sizes o i Penaeus indicus. M. dobsoni forms a major part o f the all India landing of prawn followed by P. indicus and P. monodon.

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Woodside, M. D. "Analysis of water quality problems in the VPI & SU Duck Ponds and suggested management alternatives." Thesis, Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/53725.

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Allochthonous nutrients were monitored during three storm events on one of the major tributaries entering the shallow VPI&SU Duck Ponds. Autochthonous nutrients were monitored for a period of ten months. During these storms, the stormwater runoff contributed large amounts of organic matter and fertilizer nutrients that settled in the ponds and during anoxic conditions, recycled to stimulate algal blooms. Alum was applied to one pond to reduce internal cycling of nutrients. A 25 mg/L dose of alum produced an aluminum hydroxide floc that settled to the bottom and afterwards, lowered othophosphate-phosphorus concentrations below 10 µg/L in the water column. The longevity of the one-time treatment in reducing the sediment-phosphate release rate is unknown because the monitoring program was not continued beyond July of 1988. A pond-treatment program involving copper sulfate was initiated to control algal blooms consisting mainly of the green alga, Chlamydomonas. Based on the complexing properties of the water, such as alkalinity and humics, a copper sulfate dose of 13.6 kg was determined to be a safe and effective dose that reduced algal densities but did not result in any visible adverse effects upon other aquatic life. Both of the pond management schemes were designed to aid managers of small urban ponds who have low operating budgets and a lack of technical equipment.
Master of Science

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Caporuscio, Elizabeth. "EVALUATION OF A SEQUENTIAL POND SYSTEM FOR DETENTION AND TREATMENT OF RUNOFF AT SKYPARK, SANTA'S VILLAGE." CSUSB ScholarWorks, 2018. https://scholarworks.lib.csusb.edu/etd/773.

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Understanding the extent to which human activities impact surface water resources has become increasingly important as both human population growth and related landscape changes impact water quality and quantity across varying geographical scales. Skypark, Santa’s Village is a 233.76-acre tourism-based outdoor recreation area located in Skyforest, California residing within the San Bernardino National Forest. The park is situated at Hooks Creek, the headwaters of the Mojave River Watershed, and is characterized by a diverse landscape that includes forest cover and human development, including impervious surfaces, a restored meadow, and recreational trails. In 2016, Hencks Meadow was considered degraded by human activity and restored by the Natural Resources Conservation Services (NRCS) using best management practices (BMPs) to manage stormwater runoff and mitigate pollutants entering recreational downstream surface water. Three BMP detention basins were constructed to store and improve water quality from stormwater runoff. The purpose of this study is to observe the extent to which the engineered BMP detention basins design were effective in mitigating stormwater pollution from entering Hooks Creek. Over a six to eight month period (January to August), ponds were tested in situ bi-weekly for temperature (ºC), dissolved oxygen (mg/L), pH, turbidity (NTU), conductivity (µS/cm), nitrate (mg/L), and ammonium (mg/L), with additional laboratory tests for total suspended solids (mg/L), total dissolved solids (mg/L), chemical oxygen demand (mg/L), total coliform (MPN/100mL), Escherichia coli (MPN/100mL), and trace metals (µg/L). The results of this study support that the BMP design is improving surface stormwater runoff from impervious surfaces before it enters Hooks Creek. Findings could also promote the design and implementation of stormwater BMP detention basins at other site locations where water degradation is evident. Furthermore, this research can be used to promote the necessary improvement of water quality and quantity on a widespread geographical scale.

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Lovern, Sharla Benjamin. "Assessing the Nonpoint Source Pollutant Removal Efficiencies of a Two-Basin Stormwater Management System in an Urbanizing Watershed." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/33330.

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Monitoring of a regional stormwater management facility, located on the Virginia Tech campus in Blacksburg VA, was conducted in order to assess its efficacy in reducing nonpoint source pollutant losses downstream. The facility design includes both an upper water quality (wet) pond and a lower 100-yr-event quantity (dry) pond. These on-stream ponds capture both baseflow and storm runoff from the southern portion of the Virginia Tech campus and surrounding lands, and release the water back to the unnamed stream shortly above its conjunction with Stroubles Creek, a tributary of the New River. Monitoring sites for flow measurement, water quality sampling, and biotic assessments (habitat evaluation and rapid bioassessment of benthic macroinvertebrates) were located above and below each of the ponds.

Both grab samples and automated samples were collected at these stations. Between 1997 and 1999, water quality grab samples included 35 baseflow samples and 22 stormflow samples. The grab samples were analyzed for concentrations of total suspended solids (TSS), metals, bacteria, and nutrients as well as temperature, pH, dissolved oxygen, conductivity, total organic carbon (TOC), and chemical oxygen demand (COD). Automated flow-weighted sampling was initiated in February of 1999 and results are reported through the end of October 1999. Thirty-three storms in 1999 were monitored for flow and various water quality parameters (TSS, TOC, COD, and nutrients). Pollutant loads and pollutant removal estimates were calculated with regard to the wet pond, dry pond, and the combined facility. Two types of pollutant removal efficiencies were calculated: (1) the EMC efficiency, based on pollutant concentrations from individual storms; and (2) the SOL efficiency, based on pollutant loads, to estimate long-term performance over the study period. Benthic macroinvertebrate sampling and habitat assessment were performed in both 1997 and 1999. In addition, a preliminary investigation of pond characteristics was conducted, including measurements of water quality and composition, sediment deposition and composition, and residence time.

As a system, the stormwater management facility appears to have minimum impact on improving the downstream water quality. Pollutant concentrations and loads both appear to increase downstream of the facility as compared to upstream, during both storm event and baseflow periods. Monitoring results of the benthic assemblages showed evidence of moderate to high impairment at all sampling locations, and habitat assessments showed evidence of high sedimentation levels within the stream, even after installation of the stormwater management facility. Total suspended solids (TSS) concentration removal efficiency was 10% for the combined wet pond and dry pond system, much lower than the 80 to 90% TSS removal expected for properly functioning stormwater management facilities (Hartigan, 1989). There is some evidence of sedimentation within the ponds because of a slight reduction in sediment-bound constituent export, but the dissolved nutrient constituents had either very low and most often negative (indicating pollutant export) removal efficiencies. Concentrations of metals measured in the stream often exceeded their respective acute and chronic water quality criteria at all sampling locations.

Pollutant removal efficiencies measured in the wet pond are atypical of those reported in the literature (Schueler, 1993). Insufficient residence time (two days compared to the optimal two weeks), and wet pond embankment failure are likely the principal causes of the wet pond's inadequate performance and thus, the inadequate performance of the overall facility. TSS removal efficiencies were low in the wet pond (19% for concentrations and 33% for loads) compared to the 80 to 90% expected for similar ponds. Nevertheless, the wet pond reduced the concentrations of several pollutants typically associated with TSS and not likely to be associated with the fill material for the wet pond embankment. Zinc concentrations in sediment cores were highest near the pond inlet, where the majority of sedimentation occurs. During storm events, the following results were noted. Copper and zinc concentrations in 1998 were lower at the pond outlet as compared to the pond inlet, and TOC concentrations and loads were also reduced by the wet pond (13% for concentrations and 12% for loads). However, sedimentation is also expected to remove phosphorusl, and wet pond phosphorus loads were only reduced by 10% and 3% for orthophosphorus and total phosphorus, respectively.

Because the wet pond is undersized with respect to the watershed it serves (surface area less than 1% of the watershed area (0.87 ha), as compared to the 3% ratio often recommended for optimal pollutant removal (Athanas, 1988)), higher removal efficiencies were found during baseflow periods. The greatest reductions in baseflow concentrations were for ammonia (67%), nitrate (57%), total nitrogen (54%), and COD (45%). However, the residence time of two days appears to be insufficient to reduce fecal coliform concentrations in the stream, and over 40% of the fecal coliform samples collected exceeded the water quality standard for contact recreation (DEQ-WQS, 1997). Furthermore, the wet pond did not appear to reduce TSS or TOC during baseflow periods. Export of TSS (-29% EMC efficiency) and TOC (-44% EMC efficiency) from the wet pond during baseflow periods is likely due to the wet pond embankment failure as well as pond eutrophication. Eutrophication processes are favored by the water temperature increase as flow passes through the shallow wet pond. The wet pond increased downstream temperatures by approximately 8Â°C above inflow temperatures during the summer, and to levels above 21Â°C which cannot be tolerated by sensitive coldwater species (Schueler, 1987).

The dry pond did not remove dissolved nutrient constituents or other pollutants during baseflow periods, but there is some evidence of sedimentation within the dry pond during storm events. During storm events, the dry pond was effective in removing TSS, with a concentration removal efficiency of 69% (EMC efficiency) and loading removal efficiency of 43% (SOL Efficiency). Removal of TKN and total phosphorus (36% and 37% respectively for concentrations) within the dry pond is further evidence of sedimentation within the dry pond.

The wet pond embankment was built in 1997, and monitoring occurred during a potential stabilization period when evidence of water quality benefits are slow to appear, especially with respect to downstream habitat and aquatic communities. Some benefits which could have been observed more immediately may have been negated or masked by the progressive erosion of the wet pond embankment as a result of a design flaw. Further complicating the results is the appearance; based on observations of extended drawdown time and results from a water budget analysis in the wet pond (where inflow substantially exceeds inflow); that groundwater interacts with the pond in a complicated fashion, possibly including both recharge and discharge.

To fully understand the impact of the stormwater management facility on the water quantity and quality within this tributary of Stroubles Creek, monitoring efforts should continue after the wet pond embankment is repaired and is fully operational. If biotic community improvement is desired, the stabilization period could be defined by the time necessary to flush out accumulated sediment within the channel. Monitoring efforts should also expand to include the investigation of the groundwater regime and water level fluctuations within the wet pond. Further measurements of pollutant removal processes and influences upon those processes within the wet pond should also be considered. Last, the influence of the stormwater management facility on downstream flow regimes should be investigated to assess the adequacy of its performance with regard to flow control and prevention of stream channel degradation.
Master of Science

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Nipper, Joel. "Measurement and modeling of stormwater from small suburban watersheds in Vermont." ScholarWorks @ UVM, 2016. http://scholarworks.uvm.edu/graddis/444.

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Despite decades of U.S. water quality management efforts, over half of assessed waterbody units were threatened or impaired for designated uses in the most recent assessments, with urban runoff being a leading contributor to those impairments. This cumulative research explores several aspects of urban runoff dynamics through a combination of field study and modeling. Stormwater ponds are ubiquitous in developed landscapes due to their ability to provide multiple forms of treatment for stormwater runoff. However, evolving design goals have reduced the applicability of much of the early work that was done on pond effectiveness. In this study, we instrumented a recently constructed detention pond in Burlington, VT, USA. Flow gaging demonstrated that the pond achieved a 93% reduction in event peak flow rates over the monitoring period. Storm sampling showed that the pond significantly reduced total (TN) (1.45 mg/L median influent, 0.93 mg/L median effluent, p < 0.001) and total phosphorus (TP) (0.498 mg/L median influent, 0.106 mg/L median effluent, p < 0.001) concentrations over the events sampled. A loading analysis estimated the TN and TP removal efficiencies for the pond to be 23% and 77% respectively. Lastly, temperature data collected from the pond showed that during the summer the pond accumulates considerable heat energy. This study adds to the body of literature on detention pond performance, and raises concerns about the extensive use of stormwater ponds in watersheds where thermal stress is a concern. EPA SWMM is a widely used urban hydrologic, hydraulic and water quality model, though its application can be limited due to its deterministic nature, high dimensional parameter space, and the resulting implications for modelling uncertainty. In this work, I applied a global sensitivity analysis (SA) and evolutionary strategies (ES) calibration to SWMM to produce model predictions that account for parameter uncertainty in a headwater tributary case study in South Burlington, VT, USA. Parameter sensitivity was found to differ based on model structure, and the ES approach was generally successful at calibrating selected parameters, although less so as the number of concurrently varying parameters increased. A watershed water quality analysis using the calibrated model suggested that for different events in the record, the stream channel was alternately a source and a sink for sediment and nutrients, based on the predicted washoff loads and the measured loads from the stream sampling stations. These results add to the previous work on SWMM SA, auto-calibration, and parameter uncertainty assessment. Lastly, given the extent of eutrophication impairment in the U.S., I compared TN and TP data collected in these original works with national and regional datasets. TN concentrations sampled in this work were generally commensurate with values reported elsewhere, however TP data were not. Drainage area attributes and an event based rainfall runoff analysis of the study catchments provided circumstantial support for the idea that runoff from lawns is driving the high TP loads in Englesby Brook. The role of pet wastes is considered as a potentially fruitful area for further research.

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Tu, Christine Laura. "Evaluating the lake management approach, applied biomanipulation techniques and progress in restoring ecological function of littoral macrophytes in Grenadier Pond, Canada." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0020/MQ54212.pdf.

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Lee, Shing-yip, and 李成業. "The ecology of a traditional tidal shrimp pond in Hong Kong, the production and fate of macrodetritus, and implications for management." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1988. http://hub.hku.hk/bib/B31231597.

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Martin, Darrin L. "Draining and dredging as a watershed management strategy and its impact on the zooplankton community succession of a small Midwestern pond /." Available to subscribers only, 2007. http://proquest.umi.com/pqdweb?did=1400961471&sid=2&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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Lee, Shing-yip. "The ecology of a traditional tidal shrimp pond in Hong Kong, the production and fate of macrodetritus, and implications for management /." [Hong Kong : University of Hong Kong], 1988. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12430481.

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Kitheka, Bernard M. Mr. "INVENTORY OF STORMWATER MANAGEMENT PRACTICES IN THE CITY OF OXFORD, OHIO." Miami University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=miami1274732505.

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Luksanaree, Maneechot. "Impacts of Future Climate Change in Water Resources Management at the Chao Phraya River Basin, Thailand." Kyoto University, 2020. http://hdl.handle.net/2433/259028.

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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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23

Brattgård, Nils. "Sustainable stormwater management in Stockholm's inner city." Thesis, KTH, Urbana och regionala studier, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-298539.

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Much like other cities Stockholm has traditionally used a technical system for managing stormwater. With time this system has become overburdened and has led to large environmental concerns. To reach water quality goals set by the EU Stockholm needs to decrease pollution released to recipients by 70-80%. Green infrastructure (GI) has increasingly been used as an alternative and addition to technical stormwater systems. Many studies have been conducted on different solutions and their stormwater management performance. The City of Stockholm have done research on numerous solutions to evaluate their performance in the context of Stockholm as well. However, implementation in the inner city is slow, thus this study explores why this is the case, and how Stockholm’s stormwater management goals can be reached. Stockholm predominately uses trees planted in plant beds using structural soil, and a combination of constructed wetlands and wet ponds for stormwater management. In new developments there is no real concern, as the GI can be included in planning at an early stage. Including these solutions in existing environments causes issues related to space, both above and below ground, and costs. Therefore, other solutions need to be found. This study explored green roofs, green walls and permeable pavements as possible options. Additionally, it found that finding new space that has previously not been used for GI could be an option. To mitigate financing issues new ways of promoting investment into GI from private property owners could be utilized, but that there also is a mismatch between supposed support for sustainable stormwater management on the political side and funds allocated. Finally, the study recommends that Stockholm takes the technical systems into account and explores what GI measures best work together with it to more effectively decrease pollution.

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24

Munro, Lynn I. "Development and application of dynamic models for environmental management of aquaculture in South East Asia." Thesis, University of Stirling, 2014. http://hdl.handle.net/1893/20388.

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With the world’s population set to reach 9 billion by the mid 21st century food security has never been more important. Increased competition regarding land for agricultural use and over fished seas means it falls to aquaculture to meet the global demands for protein requirements. The largest supply of aquaculture products are cultivated in South East Asia where the industry has seen rapid expansion, particularly of pond production in the past 50 years. This initial expansion has come at a cost with mangrove losses and eutrophication of natural water sources resulting. The impact of these not only affects other stakeholders, including domestic users, but effects will be felt by the aquaculture industry. Indiscriminate release of effluents to the surrounding water reduces the water quality for other users and may impact on the farm discharging the water originally. Poor water quality can then result in poor growth rates and increased mortalities reducing the profitability of the farm and endangering the livelihood of the farmer. If aquaculture is to meet the global food demand it is important that current and future enterprises are developed with sustainability at the fore front. This study investigates the nutrient dynamics in pond culture in South East Asia, focussing initially on four countries outlined by the SEAT (Sustainable Ethical Aquaculture Trade) project, including Thailand, Vietnam, China and Bangladesh. Within the four countries the main species cultured for export were identified resulting in tilapia, shrimp, pangasiid catfish and prawn. Following a farmer survey designed to collect a large volume of data over a range of topics including, water management, social, economic and ethical perceptions, dynamic models were developed, using Powersim Studio 8© (Powersim, Norway), for a generic fish and shrimp ponds separately. The models draw on data from the survey combined with other literature sources to provide outputs for Total Nitrogen and Total Phosphorus in water and sediment as well as dissolved oxygen in the pond water. One of the biggest challenges facing this study was the objective selection of relevant sites for case studies to apply the models to. With such a large preselected set of sites (200 per species per country) it was important that the method be capable of handling such large datasets. Thusly it was decided that a multivariate method be used due to the removal of any pre judgement of the data relevant to the study. In order to investigate the nutrient dynamics water management data was used in the multivariate analysis to identify any similarity between the practices occurring on farms. The case studies in this project focus on Thailand and Vietnam, covering tilapia, shrimp and pangasius. Prawn farms were disregarded as, through the survey, it was discovered most production was for domestic trade. The models were adapted to each farm case study expanding the boundary from pond level to farm level, providing an output for each pond in terms of nutrients in the water and production levels and the farm as a whole for dissolved oxygen and sediment accumulation. The results of the models suggest the culture species to be taking up much of the TN added followed by the accumulation in sediments in shrimp ponds, while TP is mostly taken up by sediments. The fish case studies suggest that most of the TN is discharged to the environment followed by uptake. While Total phosphorus shows similar results to shrimp, accumulating in the sediment. The models presented in this study can be used to estimate outputs from farms of similar water management strategies and can assist in the determination of where improvements can be made to reduce the potential for eutrophication of natural water sources.

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25

Kirvaitis, Saulius. "Raseinių žuvininkystės įmonės Keidžių siurblinės rekonstrukcijos studija." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2009. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2009~D_20090603_100432-84673.

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Magistrantūros baigiamojo darbo tema – Raseinių žuvininkystės įmonės Keidžių siurblinės rekonstrukcijos studija. Keidžių siurblinė yra Raseinių rajone. Raseinių žuvininkystės pilnasisteminis ūkis buvo įrengtas sovietiniu laikotarpiu. Keidžių siurblinė buvo pastatyta 1979 metais, kai energetinių išteklių kainos neatitiko jų realios vertės. Kadangi nuo Keidžių siurblinės pastatymo praėjo 30 metų, todėl joje esanti įranga: darbo siurbliai, jų varikliai, pagalbiniai įrenginiai yra gerokai susidėvėję, fiziškai ir technologiškai pasenę. Žuvininkystės įmonė turėtų ieškoti galimybių siurblių įrangai atnaujinti, pakeisti ją naujesne, ekonomiškesne, mažiau sunaudojančia elektros energijos. Šiuo metu Keidžių siurblinės eksploatacijos išlaidos yra palyginti didelės ir tai atsiliepia įmonės produkcijos savikainai. Siurbliams parinkti buvo kreiptasi į organizacijas, kurios yra siurblius gaminančių firmų Flygt, Grundfos, bulgarų - rusų bei čekų gamybos Intersigma atstovai Lietuvoje. LŽŪU hidrotechnikos katedra nuo 1991 m. bendrauja su Flygt firmos atstovais Lietuvoje, turi sukaupusi pakankamai daug žinių apie šios firmos produkciją. Daugiakriterinės analizės pagalba, naudojant tarptautinės atominės energijos agentūros laisvai platinamą programinę įrangą – DAM, buvo palyginti keli siurblių pakeitimo variantai ir iš jų sąlyginai išrinktas optimaliausias. Keidžių siurblinėje paprasčiausia ir racionaliausia būtų pastatyti naujus bulgarų - rusų gamybos 900D30 siurblius, tam reikėtų tik... [toliau žr. visą tekstą]
The theme of this postgraduate work is The Feasibility Study of Raseiniai Fishery Company Keidžių Pumping Station Reconstruction. The Keidžių pumping station is in Raseiniai region. Keidžių pumping station was built in 1979. 30 years passed after this station construction, so the pumps, their engines and auxiliary mechanisms of this pumping station are shabby, physically and technologically old. The pumping stations are very important element of fishery ponds, because the cost prise of fishery productions belongs on pumping station rational work. It was interviewed the firms, which sell pumps in Lithuania, and noticed that it is possible to use these pumps to replace existing old pumps: Swedish Flygt firm submersible centrifugal C series pumps, Danish Grundfos firm submersible centrifugal S series pumps, Bulgarian - Russian D type centrifugal pumps and Czech Intersigma pumps. When the technical parametres and prices were analysed, it was dermined that the most rational way is to use the cheapest Bulgarian - Russian D type pumps. The reconstruction of the pumping station is necessary in the case of the use of Grundfos or Flygt pumps, because these pumps have negative suction head, as existing pumps are with positive suction head in Keidžių pumping station. If Grunfos or Flygt pumps would be installed, vacuum pumps were not necessary in this case. The purpose of this work is to evaluate technical conditions of Keidžių pumping station hydro - technical and energetical equipment... [to full text]

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26

Žydelis, Renaldas. "Vandens kokybės parametrų kaita ir Akademijos tvenkinio įtaka jų pokyčiams Dotnuvėlės upėje." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2013. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130621_143233-75055.

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Lietuvoje kaip ir daugelyje pasaulio šalių dedama daug pastangų, kad vandenų tarša mažėtų. Pagal valstybinio monitoringo duomenis nustatyta, kad Lietuvos upėse vis dar išlieka didelės biogeninių medžiagų koncentracijos. Vandens tarša yra viena iš pagrindinių ES aplinkosaugos problemų. Norint išsiaiškinti pagrindines vandens taršos problemas, būtina atlikti nagrinėjamos upės vandens kokybės parametrų matavimus. Tam tikslui nuo 2010-11-06 iki 2013-05-07 buvo atliekami vandens kokybės tyrimai, kurių metu buvo fiksuojami šie parametrai: vandens lygis, ištirpusio deguonies koncentracijos, aktyvi vandens reakcija (pH), bendrosios mineralizacijos, elektrinio laidžio, nitratų ir vandens temperatūros kaita. Vandens kokybės parametrai matuoti aukščiau ir žemiau Akademijos tvenkinio, kuris susidarė 1968 m. ant Dotnuvėlės upės ties Akademijos gyvenviete. Pagal minėtus duomenis buvo nustatyta vandens kokybė atskiruose Dotnuvėlės ir jos intako Kačiupio upių taškuose. Atlikus tyrimą buvo nustatyta, kad Akademijos tvenkinys sąlygoja nitratų pasiskirstymą upėje, t. y. pastebėtas nedidelis nitratų padidėjimas upėje žemiau tvenkinio. Nustatyta, kad bendroji mineralizacija rudenį didėjo, žiemos metu svyravo, o pavasarį mažėjo. Pagal ištirpusio deguonies kiekį visose matavimo stotyse vanduo atitiko labai blogą, blogą, vidutinę, gerą arba labai gerą būklę. Vandens lygis Akademijos tvenkinyje tiriamuoju laikotarpiu svyravo 0−19 cm ribose stoties „O“ atskaitos atžvilgiu. Kitų išmatuotų vandens... [toliau žr. visą tekstą]
In Lithuania, as well as in other countries of the world, great efforts are made to reduce water pollution. According to the national monitoring data, there is still a high concentration of biogenic substance in Lithuanian rivers. Water pollution problem is one of the key EU environmental issues. In order to find out the main water pollution problems, it is necessary to conduct the measurements of water quality parameters of the investigated River. For this purpose, from 06/11/2010 to 07/05/2013 water quality measurements were carried out, during which values of the following parameters were recorded: water level fluctuations, dissolved oxygen concentration, pH, total dissolved solids, the variation of nitrates and water temperature. Water quality parameters were measured upstream and downstream the pond at Akademija settlement. In accordance with the given data, water quality was identified in several points of Dotnuvėlė and Kačiupio rivers. The research revealed that the pond of Akademija determines nitrate distribution in the river, i.e. a slight nitrate increase was observed in the river below the pond. It was disclosed that in autumn total dissolved solids increased, in winter the concentration varied and it decreased in spring. According to the amount of dissolved oxygen at all measurement stations, water corresponded to a poor, extremely poor, moderate, good or extremely good condition. During the research period, water level in the pond of Akademija ranged from 0-19... [to full text]

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27

Jonsson, Martin. "A performance investigation of stormwater accommodations in Stockholm : A multi-criteria decision analysis." Thesis, KTH, Industriell ekologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-210753.

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Stormwater management is a problematic area and has during the last 20 years been given an increased attention due to more pollution in the cities. The increased pollution and contaminants in stormwater implicates risks for animals, humans, the ecosystem and receiving recipients. Due to the increased attention, authorities, government and other stakeholders have developed measurements to deal with the problem. Stormwater accommodations and other type of stormwater detainment has been developed with increased modern technology and functionality to fit specific areas where different type of pollutants can vary. Stormwater treatment are necessary because it creates social, environmental and technical advantages combined with protection of ecosystem, increased multifunctionality when combining for example stormwater ponds in nature, parks or urban and rural environment. This report describes seven diverse types of stormwater accommodations systems; rain garden, stormwater ponds, wells, screen basins, infiltration trenches, pipe-/concrete magazine and swales in accordance from Structor Mark Stockholm. From these seven accommodations, three were chosen to be included in Multi Criteria Decision Analysis (MCDA). The purpose of the MCDA was to evaluate four different categories linked to stormwater, which are environment, social, technology and economical categories. These categories are broad concepts; therefore, parameters were developed to narrow down the areas within the concept, from which the area of investigation was founded within. The parameters created for each category are degree of purification for the environmental category, performance and maintenance for the technological category, aesthetical and social benefits for the social category and costs and risk for the economical category. The criteria developed from these parameters are specific topics that was scored from the scale between 0-5, where 0 = insignificant, 1= Low, 2= Moderate, 3= Major, 4=High, 5= Very high. A reference option was also created, considered as “no commercial treatment of stormwater”, only to transport stormwater. This reference option was also referred to as a zero-alternative and is drainage by piping. The scoring was conducted by stakeholders and citizens of Stockholm. The scoring of the three chosen stormwater accommodations and the reference alternative after calculating the mean value and summarize it resulted in that stormwater pond received the highest overall score of 11.9 followed by rain gardens 11.4, infiltration trench 11.3 and drainage by piping 7.3. The stakeholders are influential people that works either with stormwater, layout and planning or maintenance personnel. Citizens of Stockholm provided inputs only in regards of the social aspects. A total of 20 stakeholders were contacted and 5 stakeholders participated in the scoring procedure. Citizens were interviewed on the street; a total of 60 people was asked to participate and 13 people decided to participate in the scoring procedure of the social aspects. Although, the attendance of stakeholders was low, they are still considered important to this project since they provided the scoring of the criteria for each respective category (environment, technology, social and economic). In regards of the low attendance by stakeholders, this resulted in a way that it became hard to distinguish the result between the different stormwater accommodation. Therefore, it was hard to determine which stormwater accommodation that was the best out ofthe ranking provided by the MCDA. A benefit by using MCDA as a tool in this case, gave an indication that the MCDA can work as a framework to decision makers, even though the result in this case became difficult to manage and distinguish between the different stormwater accommodations. Finally, the method, layout and analysis itself can provide means of measurements for stormwater investigations when the purpose is to choose between the best stormwater systems included in the MCDA. Inputs from stakeholders concluded that depending on what type of existing circumstances, there must be a site-specific evaluation to treat every area as a unique area, before deciding what type of stormwater accommodation to apply to that specific location.
Dagvattenhantering är ett problematiskt område som under de senaste 20 åren har fått allt mer uppmärksamhet då mer föroreningar uppdagats i städerna. Den ökande föroreningen av dagvatten tenderar att orsaka en större risk för djur, människor, ekosystem och recipienter dit dagvatten rinner. På grund av uppmärksamheten som dagvattenhanteringen har fått, har myndigheter, regering och andra intressenter utvecklat dagvatten teknologin ytterligare för att skapa en modern dagvattenstrategi för att handskas med problemet. Dagvattenhantering är nödvändigt eftersom den skapar sociala, miljömässiga och tekniska fördelar samt om dagvattensystemen kombineras med funktionalitet så kan detta ge ökat skydd för ekosystemen samt förbättrad hälsa hos befolkningen i städerna. Den här rapporten beskriver sju olika typer av dagvattensystem så som; rain gardens, dagvattendammar, brunnar, skärmbassänger, svackdiken, rör-/betong magasin samt krossdiken på begäran av Structor Mark Stockholm. Utav dessa 7 dagvattensystem, ingick 3 anläggningar i en så kallad multi-criteria decision analysis (MCDA). Syftet med en MCDA är att utvärdera fyra olika kategorier som kan förknippas med dagvattenhantering. Kategorierna är miljömässiga, sociala, tekniska och ekonomiska. Dessa kategorier utger dock ett brett budskap och för att begränsa analysen så skapades parametrar. Dessa parametrar skapas utifrån varje enskild kategori. För den miljömässiga kategorin skapades parametern grad av rening, för den tekniska kategorin skapades parametern prestanda och underhåll, för den sociala kategorin skapades parametern estetiska och sociala fördelar, och slutligen för den ekonomiska kategorin skapades parametern kostnader och risker. Utifrån dessa parametrar skapades sedan kriterier med specifika huvudämnen som kan bedömas enligt en poängskala från 0-5 där 0 = insignificant, 1=Low, 2= Moderate, 3= Major, 4= High, 5= Very high. Tre dagvattensystem inkluderas i MCDA vilket var; rain gardens, dagvattendammar, krossdiken vars syfte är att rena och fördröja dagvatten. Ett referensalternativ skapades också som ävenkallas ”zero-alternative”, vilket anses inte ha någon rening av dagvatten utan är endast ett transportsystem för dagvatten. Detta referensalternativ kallas drainage by piping. Poängsättningen gjordes av intressenter och invånare i Stockholm. Intressenterna är människor som arbetar med dagvattenhantering antingen på planeringsstadiet eller ute i fält som drift och underhålls personal. Invånare i Stockholm bedömde endast den sociala kategorin eftersom det kan sakna kunskap och insyn i det miljömässiga, tekniska och ekonomiska detaljerna. Totalt kontaktades 20 intressenter där 5 personer valde att medverka i MCDA. Invånare i Stockholm intervjuades på stan, totalt frågades ca 60 personer varav 13 personer valde att medverka i poängsättningen. Poängsättningen av de tre valda dagvattensystemen samt referensalternativet, efter beräkningav medelvärdet samt den totala summeringen resulterade i att dagvattendammar fick den hösta poängen 11,9 hamnade rain garden på andra plats med 11,4, krossdike på tredje plats med 11,3 samt referensalternativet på en fjärde plats med 7,3. De tre dagvattensystemen hade ett relativt liknande slutgiltigt resultat. Dock så skilde sig den individuella kategoriska bedömningen av miljömässiga, tekniska, sociala samt ekonomiska aspekten med större varierande resultat. Även om deltagandet av intressenter var relativt lågt, endast 25 % av det kontaktade intressenterna valde att ställa upp, så anses dessa intressenter vara viktiga för det här projektet då de, utifrån deras kunskap, bedömer det uppsatta kriterierna och det är denna bedömning som resultatet baseras på. Resultaten mellan det olika dagvattenanläggningarna som var inkluderade i MCDA var svåra att särskilja, troligtvis beroende på att ingen viktningsmetod användes. Däremot så är en fördel med MCDA som verktyg i det här fallet, att det gav en indikation på att MCDA kan fungera som ett stödjande verktyg för beslutsfattare även om resultatet i det här fallet var svårt att särskilja. Själva metoden, upplägget och analysen kan användas som medel för att avgöra vilken typ av dagvattenanläggning som passar bäst utifrån de kriterier som är uppsatta. Slutligen så gav intressenterna en påvisning att dagvattenanläggningar ska konstrueras så att hänsyn tas till omkringliggande omständigheter, där varje plats ska ansesvara unik. Det krävs en platsspecifik utredning där hänsyn till geologiska, geotekniska,hydrologiska samt infrastrukturella och miljömässiga aspekter bör utredas innan valet av dagvattensystem bestäms.

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Rolon, dos Santos Mérette Muriel. "Primary Production and Nutrient Dynamics of Urban Ponds." Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/20658.

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In urban areas, stormwater management ponds (SWPs) are built to mitigate polluted runoff. Although these ponds are increasing in numbers, their ecology is not well understood. Physical and chemical characteristics of 17 SWPs in the City of Ottawa were measured to determine the drivers of phytoplankton biomass (Chl. a) and primary production (PP). While total phosphorus was the best predictor of algal biomass in the ponds (as in lakes), the imperviousness of the catchment could also predict Chl. a. Planktonic PP in two ponds measured seasonally was more closely related to water residence time than to nutrient concentrations with rates approaching at times the theoretical maximum for aquatic systems. In one pond, whole ecosystem metabolism, estimated using diel changes in dissolved oxygen and δ18O-O2, suggested that these hypereutrophic systems were net sinks for carbon in the summer but likely sources to the atmosphere at other times of the year.

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Blekic, Demir, and Adam Fritz. "Förslag på generell arbetsprocess för utredningar av befintliga dagvattendammar ur ett funktionellt perspektiv." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Byggnadsteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-31646.

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Syfte: I dagens läge byggs nya dagvattendammar för att magasinera dagvatten som överbelastar dagvattenledningssystemen och de befintliga dagvattendammarna förblir utan översyn. Eftersom klimatförändringar bidrar till att femårsregn kommer i en högre frekvens ökar flödet av dagvatten och orsakar att allt fler dagvattendammar kommer att bli underdimensionerade. För att bevara samhällsfunktioner utreds en generell arbetsprocess hur kommuner kan undersöka och bevara befintliga dagvattendammar. Metod: Metoderna som används är intervju, fallstudie och litteraturstudie. Intervju bidrar till att lösningar och förslag av undersökningsmetoder och åtgärdsförslag samlas in. Fallstudien utfördes på tre olika dagvattendammar och undersöker vilka undersökningsmetoder som kan användas. Att samla empiri i ett praktiskt fall bör bidra till att utredningens trovärdighet förstärks. De metoderna som användes i fallstudien är beräkningar, sedimentprovtagning och dokumentanalys från underlag av befintliga dagvattendammar. Med hjälp av litteraturstudie analyseras utredningens empiri med andra källor för att kontrollera empirins tillförlitlighet. Resultat: Ett flertal undersökningsmetoder och åtgärdsförslag analyserades. Tre undersökningsmetoder som passade en generell arbetsprocess var: flödesproportionell provtagning, sedimentprovtagning och dagvattenberäkningar med dagvattenmodellen Stormtac. Åtgärdsförslag som passade var: byggnation av en vall runt dammen för att utöka magasineringen, plantering av växter som tar upp näringsämnen och tungmetaller bundna i dagvattnet, utnyttja dagvattendammens form där dagvattendammens hydrauliska effektivitet utnyttjas maximalt samt anlägga fördamm med en makadamvall med vattenlevande växter. Konsekvenser: Flödesproportionell provtagning var tillförlitlig undersökningsmetod enligt intervju och litteraturstudie. Sedimentprovtagning av sediment i botten av inoch utlopp går att nyttjas i en generell arbetsprocess, men vissa föroreningshalter kan vara missvisande beroende på hur detaljerat sedimentprovtagningen görs. Dagvattenmodellen Stormtac och dess beräkningar kan nyttjas i en generell arbetsprocess eftersom Svenskt Vatten P110 (2016) bekräftar modellens beräkningar. Åtgärdsförslagen testades inte i verkliga fall, men effekten bekräftades i intervjun och litteraturstudien. Ett förslag på generell arbetsprocess kunde sammanställas. Stickprovstagning passar sämre in i en generell arbetsprocess. Begränsningar: Fallstudien har begränsats genom att utreda två metoder, varav den ena är dagvattenmodellen Stormtac och den andra är sedimentprovtagning. Utvalda föroreningar som tungmetaller, olja, kväve och fosfor analyseras. Studien avgränsas från att analysera hur recipienter påverkas av de befintliga dagvattendammar som studerats.
Purpose: At present are new stormwater ponds constructed to store stormwater which overloads stormwater pipe systems while existing stormwater ponds remains without overhaul. Since climate changes contributes to five-year rain in a higher frequency, which increases the flow of stormwater and causing more stormwater ponds to be undersized. In order to preserve social functions, are a general work process investigated of how municipalities can investigate and preserve their existing stormwater ponds. Method: The methods that are used are interviews, case study and literature study. The interviews contribute to solutions and proposals of investigation methods and proposals for action. The case study were performed in three stormwater ponds and examines the investigation methods that can be used. Collecting empirical data in a practical case, should increase the investigation’s credibility. The methods used in the case study are calculations, sediment sampling and document analysis of the basis of existing stormwater. Using literature study are the empirical data of the investigation analyzed with other sources to check the reliability of the empirical data. Findings: Several methods of investigations and action proposals were analyzed. Three investigation methods which fit a general work process were: flow proportional sampling, sediment sampling and stormwater calculations through the stormwater model Stormtac. The proposals for action which suited a general work process were: construction of a trench around the pond to expand the storage area, planting plants that take up nutrients and heavy metals tied up in stormwater, exploit the stormwater ponds shape where the hydraulic efficiency are exploited flat out by placing the inlet and outlet on opposite ends, and building trenches with a gravel embankment with aquatic plants. Implications: Flow proportional sampling were a reliable investigation method according to interview and literature study. Sediment sampling of sediment in bottom of in- and outlet can be used in a general work process, but certain contamination levels can be misleading depending on how detailed sediment samplings are done. Stormwater model Stormtac and its calculations can be used in a general workprocess because publication Svenskt Vatten P110 (2016) are confirming the models calculations. The proposals for action were not tested in real cases, but the effect was confirmed in the interview and literature study. Limitations: The case study was limited by investigating two methods, one of which is stormwater model Stormtac and sediment sampling. Selected contaminants such as heavy metals, oil, nitrogen and phosphorus are analysed. The study is delimitated by analyzing how recipients are affected by the studied existing stormwater ponds.

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Kabbani, Muhieddine Saadeddine. "Using PCSWMM to simulate first flush and assess performance of extended dry detention ponds as structural stormwater BMPs in a large polluted urban watershed." Diss., University of Iowa, 2015. https://ir.uiowa.edu/etd/1653.

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Urbanization and increase of impervious areas impact stormwater runoff and can pollute receiving waters. Total suspended solids (TSS) are of particular concern as they can act as a transport agent for other pollutants. Moreover, the existence of the first flush phenomenon (FF), whereby the first stage of storm runoff is the most concentrated, can also have profound ecological effects on receiving waters. Understanding the various types of pollutants in watershed stormwater, their correlation with rainfall parameters (precipitation depth and previous dry days) and with TSS, and the existence of FF is crucial to the design of the most suitable structural best management practice (BMP) that can mitigate their harm. Personal Computer Storm Water Management Model (PCSWMM) is a well-known computer model that can simulate urban runoff quantity and quality and model BMPs. The use of PCSWMM to simulate the first flush phenomenon and to evaluate the effectiveness of structural BMPs has not been previously investigated for a large urban watershed with seriously polluted stormwater runoff. This research is concerned with the study of a framework for designing structural best management practices (BMPs) for stormwater management in a large watershed that is based on comprehensive analysis of pollutants of concern, rainfall parameters of influence, and the existence of FF. The framework was examined using the PCSWMM computer model in the St Anthony Park watershed, an urban watershed in St Paul, Minnesota with a large drainage area of 3,418 acres that discharges directly into the Mississippi River via a storm tunnel. A comprehensive study was undertaken to characterize the overall St. Anthony Park watershed stormwater quality trends for the period of record 2005-2013 for heavy metals, nutrients (ammonia and total phosphorus), sediment (TSS), and bacteria (E. coli). Stormwater was found to be highly contaminated as measured by exceedance of the Minnesota Pollution Control Agency (MPCA) water quality standards and as compared to data obtained from the National Stormwater Quality Database (NSQD). None of the examined parameters significantly correlated with precipitation depth. Concentrations of most heavy metals, total phosphorus and TSS positively correlated with previous dry days, and most pollutants correlated positively with TSS, which provided a strong rationale for using TSS as a representative pollutant in PCSWMM and in examining BMP efficiency. Moreover, BMPs that targeted the particulate fraction in stormwater would be the most efficient in reducing stormwater pollution. A PCSWMM model was built based on the existing drainage system of the watershed, which consisted of inlet structures, manholes, pipes and deep manholes that connect the network pipes to a deep drainage tunnel discharging directly into Mississippi River. The model was calibrated and validated using recorded storm and runoff data. FF was numerically investigated by simulating pollutant generation and washoff. Using three different numerical definitions of FF, the existence of FF could be simulated, and was subsequently reduced by simulating extended dry detention ponds in the watershed. Extended dry detention ponds (EDDPs) are basins whose outlets are designed to detain stormwater runoff for a calculated time that allows particles and associated pollutants to settle. Extended dry detention ponds are a potential BMP option that could efficiently control both water quantity (by diverting initial volumes of stormwater, thus addressing FF) and quality (by reducing suspending pollutants, thus addressing TSS and co-contaminants). Moreover, they are the least-expensive stormwater treatment practice on a cost per treated unit area. Two location-based designs were examined. The first was an EDDP at the main outfall (OFmain), while the second was a set of seven smaller EDDPs within the vicinity of deeper manholes of the deep tunnel (distributed EDDPs). Distributed EDDPs were similar to the OFmain EDDP at reducing peak stormwater flow (52-61%) but superior in reducing TSS loads (20-25% for small particles and 43-45% for larger particles based on the particle sedimentation rate removal constant k) and in reducing peak TSS loads (67-75%). These efficiencies were obtained using the dynamic and kinematic wave routing methods, indicating that they could be used interchangeably for this watershed. The steady state routing method produced unrealistic results and was subsequently excluded from FF analysis. Finally, distributed EDDPs were superior to OFmain EDDP at eliminating FF per the stringent fifth definition (Δ > 0.2). This was true for small values of k. However, larger values of k and other FF tests (above the 45º no-flush line and FF coefficient b < 1) showed that BMP implementation overall failed to completely eliminate FF. This suggested that the extended time required by EDDPs to efficiently remove pollutants from stormwater via settling would compromise their ability to completely eliminate FF. In conclusion, a comprehensive framework was applied so as to better design the most efficient BMPs by characterizing the overall St. Anthony Park watershed stormwater pollutants, their correlation with rainfall parameters and with TSS, and the magnitude of FF. A cost-effective, rapid, and accurate method to simulate FF and study the optimal BMP design was thus implemented for a large urban watershed through the PCSWMM model.

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Jones, Jamie. "Chemophysical Characteristics and Application of Biosorption Activated Media (BAM) for Copper and Nutrient Removal in Stormwater Management." Master's thesis, University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5954.

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For high groundwater table areas, stormwater wet detention ponds are utilized as the preferred stormwater management throughout the state of Florida. Previous research has found that accumulations of nutrients, algae, heavy metals, pesticides, chlorophyll a, fecal coliform bacteria and low concentrations of dissolved oxygen (DO) are common characteristics of stormwater wet detention ponds. Although these pollutant levels are not regulated within the ponds, states are required to compute the pollutant load reductions through total maximum daily load (TMDL) programs to meet the water quality requirements addressed by the Clean Water Act (CWA). In this study, field sampling data of stormwater ponds throughout Florida are presented to identify concentration levels of the main contaminants of concern in the discharge of wet detention ponds. Sampling was done to identify possible sources, in addition to possible removal mechanisms via the use of specific sorption media. Nutrients were found as a main problematic pollutant, of which orthophosphate, total phosphorus, ammonia, nitrate, and total nitrogen were targeted whereas heavy metals exhibited minor concerns. Accumulation of high nutrient concentrations may be mitigated by the adoption of best management practices (BMPs) utilizing biosorption activated media (BAM) to remove phosphorus and nitrogen species through physical, chemical, and biological processes. This study aims to increase overall scientific understanding of phosphorus removal dynamics in sorption media systems via Langmuir and Freundlich isotherms and column studies. The removal of phosphorus (P) was proven effective primarily through chemophysical processes. The maximum orthophosphate adsorption capacities were determined under varying conditions of the media within the columns, which were found up to 0.000534 mg-P adsorbed per gram BAM with influent concentrations of 1 mg?L-1 orthophosphate in distilled water and 1 hour hydraulic residence time (HRT). When using spiked pond water under the same conditions, the adsorption capacity was increased about 30 times to 0.01507 mg-P?g-1 BAM presumably due to the properties and concentrations of ions affecting the diffusion rate regulating the surface orthophosphate reactions. These equilibrium media uptake values (q) were used to calculate the life expectancies of the media under varying HRT and influent concentrations of treatment. Chemophysical and biological removal capabilities of the media for total nitrogen, ammonia, and nitrate were effective in columns using 1100 g of BAM. In flow-through column conditions, ammonia had a consistent ~95% removal while effluent nitrate concentrations were highly variable due to the simultaneous nitrification-denitrification processes once an aerobic-anaerobic environment was established. Batch column experiments simulating no-flow conditions within a media bed reactor resulted in orthophosphate removals comparable with the continuous flow conditions, increased total phosphorus effluents indicative of chemical precipitation of orthophosphate, decreased ammonia removal, and increased nitrate removal. Due to a biofilm's sensitivity to even low copper concentrations and accumulation in ponds, a copper sorption media mix of “green” materials was generated. Freundlich and Langmuir isotherm tests concluded a successful mix resulting in copper removal efficiencies up to 96%.
M.S.
Masters
Civil, Environmental, and Construction Engineering
Engineering and Computer Science
Environmental Engineering; Environmental Engineering Sciences

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Angelim, Susane Campos Mota. "Estudo em escala real da disposição de resíduo de decantador de ETA em lagoa de estabilização de esgoto." Universidade Federal de Goiás, 2015. http://repositorio.bc.ufg.br/tede/handle/tede/5007.

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Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG
In Brazil water treatment plants (WTP) residuals are usually discharged into waterways, with negative impacts on water quality, aquatic biota and sediments, which may also pose risks to human health. This paper presents a study on real scale disposal of aluminum sludge from the settling of a WTP in a primary facultative pond, both located in Piracanjuba-GO, wishing to contribute as an alternative for residuals management. The study aimed to evaluate the effects of WTP residuals (WTPR) in the performance of the wastewater stabilization pond (WSP), in terms of quality of the effluent and volume of bottom sludge accumulated. Worked up in two identical parallel ponds, one in which WTPR was applied (test pond) and another without application (control pond) to serve as comparison of results. The study was carried out in two stages, with dosage of 37 mg TS/L in Phase 1 and 44 mg TS/L in Phase 2, totaling 125 days of application and 191 days of monitoring. It was evaluated several effluent parameters such as BOD, solids, nitrogen, total phosphorus, Escherichia coli, metals, among others. Sludge volumes in the ponds were obtained from bathymetric survey using a sludge depth meter (sludge gun) and modeling by Surfer 8.0 software. The addition of the WTPR did not impair the performance of the test pond, with minimal reduction of BOD and nitrogen. It was not possible to identify any influence of WTPR for the removal of total phosphorus of the sewage, which was attributed to high pH and low dosage. There was no statistical difference (95% confidence level) between the means of 15 parameters evaluated in two phases, except for nitrogen ammonia. There was no difference between the increases of sludge volume accumulated in the bottom of the ponds, although total solids content was higher in the test pond. This behavior was associated with particle size characteristics of the material. The study indicates technical feasibility of WTP residuals disposal in the WSP studied, revealing an alternative for its management that can also be applied in other same type systems if evaluated the specific conditions in each case.
A realidade brasileira atual é de que a grande maioria dos resíduos de ETA são lançados diretamente em cursos d'água, com impactos negativos sobre a qualidade das águas, biota aquática e sedimentos, podendo também representar riscos à saúde humana. O trabalho apresenta um estudo em escala real da disposição do resíduo do decantador da ETA do tipo convencional (ou de ciclo completo) da cidade de Piracanjuba-GO, cujo coagulante utilizado é o sulfato de alumínio, na lagoa facultativa primária da ETE Piracanjuba, visando contribuir como alternativa adequada para a gestão dos resíduos sólidos de sistemas de saneamento. O trabalho teve como objetivo avaliar os efeitos da disposição do resíduo no desempenho da lagoa quanto à qualidade do efluente líquido e ao volume do lodo de fundo acumulado. Trabalhou-se com duas lagoas idênticas em paralelo, uma de teste, onde foi aplicado o resíduo, e outra de referência, sem aplicação, para servir de comparação dos resultados. O estudo foi realizado em duas fases de aplicação do resíduo e monitoramento das lagoas, com dosagem de 37 mgSTresíduo (bs)/Lesgoto na Fase 1 e 44 mgSTresíduo (bs)/Lesgoto na Fase 2, totalizando 125 dias de aplicação e 191 dias de monitoramento. Foram avaliados diversos parâmetros físico-químicos do efluente, tais como DBO, SST, Namoniacal, fósforo total, E.coli, metais, dentre outros. Os volumes de lodo nas lagoas foram obtidos a partir de levantamento batimétrico com uso de medidor de óptico de lodo (Sludge Gun) e calculados por modelagem matemática pelo programa Surfer 8.0. A adição do resíduo de ETA não prejudicou o desempenho da lagoa facultativa de teste, com discreta redução de DBO e Namoniacal. Não foi possível apontar nenhuma influência do resíduo de ETA sobre a remoção de fósforo total do esgoto, o que foi atribuído a fatores como elevado pH e baixa dosagem. Na análise estatística dos resultados do efluente, ao nível de confiança de 95%, não foram verificadas diferenças estatísticas entre as médias dos 15 parâmetros avaliados nas duas fases, exceto para Namoniacal. Não houve diferença entre os acréscimos de volume de lodo de fundo acumulado nas lagoas, sendo que concentração de sólidos totais do lodo de fundo foi maior na lagoa de teste. Esse comportamento foi associado a características granulométricas do material. O estudo indica a viabilidade técnica da disposição do resíduo da ETA nas lagoas facultativas da ETE Piracanjuba, mostrando-se como uma alternativa ambientalmente adequada para a gestão do resíduo, que pode ser aplicada também em outros sistemas de mesmas tipologias, desde que avaliadas as condições específicas de cada caso.

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Haley, Norman Victor DeVries Dennis R. Wright Russell A. "Privately-owned small impoundments of central Alabama a survey and evaluation of management techniques and enhancements /." Auburn, Ala, 2009. http://hdl.handle.net/10415/1782.

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Girard, Léo. "Étangs piscicoles et services écosystémiques : Relations entre pratiques de gestion, maintien de la biodiversité et stockage de carbone." Electronic Thesis or Diss., Paris, AgroParisTech, 2024. http://www.theses.fr/2024AGPT0008.

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L'Europe renferme de nombreux paysages d'étangs, pour beaucoup avec une origine pouvant remonter au Moyen-âge et une vocation historique de production piscicole. Ces milieux, malgré qu'ils soient anthropisés, sont connus pour leur capacité à présenter une biodiversité importante, avec des espèces rares, voir endémiques ou menacées. Avec l'abandon de la pisciculture, combiné à d'autres menaces comme le changement climatique, un nombre significatif de ces étangs ont disparus au cours des dernières décennies. Jusqu'à récemment, et ce malgré le rôle important qu'ils peuvent jouer, ces petits plans d'eau ont de plus été négligés en Recherche, mais également par les politiques publiques.Dans ce travail de thèse nous nous sommes intéressés aux effets de différentes pratiques de gestion piscicoles sur certains services écosystémiques rendus par les étangs piscicoles. Dans un premier temps, nous avons analysé la pratique de l'assec et ses impacts à la fois sur la biodiversité et sur la productivité en poissons. Dans un second temps, nous avons exploré les impacts de différentes gestions de la densité piscicole sur les caractéristiques des communautés de macrophytes. Et enfin, nous avons étudié les étangs piscicoles comme potentiels puits ou sources de carbone, et les effets des pratiques de gestion sur ces bilans carbone.Pour compléter les connaissances scientifiques sur ces thématiques, nous avons capitalisé sur des données historiques collectées en Dombes (Ain, France) depuis 2007, mais également sur des données collectées dans le cadre du projet européen PONDERFUL, entre 2021 et 2022, en Dombes et dans le Midden-Limburg (Belgique). Nous avons analysé à la fois des données sur la physico-chimie de l'eau et des sédiments, ainsi que des données de biodiversité (macrophytes, phytoplancton et macroinvertébrés), de stockage et d'émissions de carbone, ainsi que sur les pratiques de gestion piscicoles (distance au dernier assec, empoissonnage, fertilisation).Nos résultats démontrent que l'assec constitue une pratique agroécologique majeure pour la pisciculture extensive en étang. Cet assèchement volontaire favorise la recolonisation des macrophytes ainsi que leur diversité lors de la remise en eau. La deuxième année en eau est caractérisée par un “état instable” d'équilibre entre les deux producteurs primaires. Cet état apparait comme étant favorable à la fois à la biodiversité, à la production mais également au stockage du carbone. L'intensification de la production, à travers une augmentation des densités piscicoles, a néanmoins des effets négatifs sur la richesse spécifique des macrophytes. Elle impacte également la structure des communautés. Les étangs piscicoles possèdent des sous-ensembles d'espèces, nichés dans les communautés plus riches des étangs gérés sans poissons. Nous avons également pu montrer une très forte variabilité sur les bilans carbone réalisés sur 20 étangs piscicoles. En moyenne, les étangs monitorés apparaissent comme étant plutôt des puits de carbone, à hauteur d'environ 4 tonnes de CO2 équivalent stocké par hectare et sur 6 mois. La phase d'assec est quant à elle caractérisée par des émissions de gaz à effet de serre importantes.Tous ces éléments permettent de confirmer que les étangs piscicoles, associés à des pratiques extensives, peuvent fournir de nombreux services écosystémiques. La production piscicole n'est pas antinomique de la conservation de la biodiversité. La pérennité de ces milieux dans les paysages européens, et des services fournis, passe par le maintien de ces pratiques de gestion. Même si concilier les services d'approvisionnement et de support semble possible, à l'avenir, une hiérarchisation des services souhaités sera nécessaire, notamment au regard des effets inverses que peuvent avoir certaines pratiques de gestion
Europe is home to a large number of “pond landscapes”, many with origins dating back to the Middle Ages and a historic vocation for fish farming. Despite their man-made nature, these environments are known for their capacity to harbor significant biodiversity, with rare, even endemic or endangered species. With the abandonment of fish farming, combined with other threats such as climate change, a significant number of these ponds have disappeared in recent decades. Until recently, and despite the important role they can play, these small water bodies have been neglected in research, but also in public policies.In this PhD thesis work, we looked at the effects of different fish farming management practices on ecosystem services provided by fish ponds. First, we analyzed the practice of drying-out ponds and its impact on both biodiversity and fish yields. Secondly, we explored the impacts of different fish density management on macrophyte community characteristics. And finally, we studied fish ponds as potential carbon sinks or sources, and the effects of management practices on these carbon balances.To contribute to the scientific knowledge on these topics, we capitalized on historical data collected in the Dombes region (Ain, France) since 2007, but also on data collected as part of the European PONDERFUL project, between 2021 and 2022, in Dombes and Midden-Limburg (Belgium). We analyzed data on water and sediment physico-chemistry, as well as biodiversity (macrophytes, phytoplankton and macroinvertebrates), carbon storage and emissions, and fish farming management practices (time since the last dry year, fish stocking, fertilization).Our results show that drying-out is a major agroecological practice for extensive pond fish farming. This voluntary draining facilitates the recolonization of macrophytes and their diversity when the pond is re-watered. The second year in water is characterized by an "unstable state" of equilibrium between the two primary producers. This state appears to be favorable to biodiversity, production and carbon storage. Intensification of production, through increased fish densities, nevertheless has negative effects on macrophyte species richness. It also impacts community structure. Ponds used for fish farming have subsets of species that nest in the richer communities of ponds managed without fish. We were also able to show a very high degree of variability in the carbon balances of 20 fish ponds. On average, monitored ponds appear to be carbon sinks, with around 4 tonnes of CO2 equivalent stored per hectare over 6 months. The dry year, on the other hand, is characterized by high greenhouse gas emissions.All these elements confirm that fish ponds, combined with extensive practices, can provide numerous ecosystem services. Fish production is not incompatible with biodiversity conservation. The sustainability of these environments in European landscapes, and of the ecosystem services they provide, depends on the maintenance of these management practices. Even if it seems possible to reconcile provisioning and support services, in the future it will be necessary to establish a hierarchy of desired services, particularly in view of the inverse effects that certain management practices may have

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35

Filbrun, Jesse Everett. "An Ecological Approach to Feed Management in Fish Rearing Ponds." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1366038927.

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Gan, T. J. "Propofol for the management of postoperative nausea and vomiting (PONV)." Thesis, University College London (University of London), 2008. http://discovery.ucl.ac.uk/1445292/.

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Postoperative nausea and vomiting (PONV) is one of the most common complications following surgery. Despite better anaesthetic techniques, and the availability of newer generations of antiemetics, the incidence of PONV is still as high as 60-70% in high-risk subjects. Patients rated symptoms of nausea and vomiting as highly undesirable and are willing to pay out of pocket a substantial amount for an effective antiemetic. PONV also has major economic implications, prolonging recovery room and hospital stay, and in some cases, increases patient morbidity. Propofol is an intravenous anaesthetic which gained rapid popularity due to its favourable pharmacokinetic and pharmacodynamic profile. In particular, it is associated with rapid recovery, making it the intravenous anaesthetic agent of choice especially in ambulatory anaesthesia. Previous studies have demonstrated that total intravenous anaesthesia with propofol is associated with a lower incidence of PONV when compared with inhalational anaesthetic. However, it is unclear regarding the dose response of propofol when used as an antiemetic, and how propofol should be administered in the perioperative period for its antiemetic effects. The over arching goal of this MD thesis is to examine the use of propofol for its antiemetic properties. First, we assessed the extent of clinical practice of using propofol for its antiemetic effects among US anaesthesiologists. Next, we determine the dose response of propofol for its antiemetic effects. We examined the efficacy of propofol when used as antiemetic prophylaxis as well as for the treatment of established PONV. Different regimens of propofol administration were assessed for its prophylactic antiemetic effects. Treatment of established PONV was assessed using a patient controlled antiemetic system. We also determined the use of propofol in a multimodal PONV prevention strategy as well as its use in paediatric population. The main objective of these series of investigations was to systematically determine the antiemetic effects of propofol and recommend how propofol should be used in clinical practice.

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Ponn, Josef [Verfasser]. "Situative Unterstützung der methodischen Konzeptentwicklung technischer Produkte / Josef Christian Ponn." München : Verl. Dr. Hut, 2007. http://d-nb.info/999941518/34.

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Robinson, Cynthia Barbara Elizabeth. "Ponds in southern Ontario, a case study of management and hydrology." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ56669.pdf.

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39

Bradshaw, Jeffrey Donald. "Bean pod mottle virus biology and management in Iowa." [Ames, Iowa : Iowa State University], 2007.

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Bolt, Jeffrey M. "iPod, You-pod, We All Pod For Stress Relief:An Investigation of Mood-Management Through Digital Portable Music Players." Kent State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=kent1459350298.

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41

Černá, Karolína. "Destinační management a jeho praktická aplikace v oblasti Pece pod Sněžkou." Master's thesis, Vysoká škola ekonomická v Praze, 2012. http://www.nusl.cz/ntk/nusl-150375.

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The aim of this paper is an evaluation of destination's management in particular czech tourist destination. The paper begins with the theoretical part which explains basic relations and issues in management of destination. Such information is then applied in the practical part on destination Pec pod Sněžkou. It begins with the introduction of the destination. Afterwards are described main subjects, form of their cooperation and results of their activities. The deduction of the paper features an evaluation of destination and it's management and recommendations to the future.

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West, Phillip D. "Use of Ponds and Lakes by Resident Canada Geese." W&M ScholarWorks, 2003. https://scholarworks.wm.edu/etd/1539626404.

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Beau, Frédéric. "Ecologie de la Cistude d'Europe "Emys orbicularis" en Brenne : histoire de vie des nouveau-nés et influence des modes de gestion sur les populations." Thesis, La Rochelle, 2019. http://www.theses.fr/2019LAROS024.

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La Brenne est une région qui abrite aujourd’hui une biodiversité remarquable et de nombreuses espèces emblématiques des zones humides, parmi lesquelles la Cistude d’Europe Emys orbicularis occupe une place particulière. Cette espèce a été largement favorisée par les activités humaines passées. Les étangs, tous artificiels, ont vu s’installer et se développer depuis le Moyen Âge une des plus importantes populations de France. Cette espèce, dont la répartition française fut plus large, a subi d’importantes réductions essentiellement en raison des modifications des pratiques agricoles et l’utilisation, voire la disparition, des milieux aquatiques et terrestres nécessaires à son cycle de vie. Les Réserves naturelles sont des lieux de préservation du patrimoine naturel. La biologie de la conservation s’attache à proposer des mesures de préservation sur la base d’études scientifiques. Ce travail s’inscrit dans cette démarche sur une espèce pourtant déjà largement étudiée. Cette dernière considération nous a amené à porter nos recherches sur des éléments nouveaux pour l’espèce. Ainsi, nous avons souhaité tout d’abord étudier les facteurs liés aux sites de ponte : l’incubation in situ, les émergences et les premiers moments de vie des nouveau-nés qui quittent le nid. Puis, nous avons étudié les populations dans les étangs sous le prisme de la qualité des milieux aquatiques. Concernant notre premier objectif, jusqu’à présent les sites de ponte étaient considérés, et donc gérés, comme des lieux à optimiser pour la ponte des femelles. Or, il s’avère que l’utilisation de cet habitat terrestre par l’espèce va bien au-delà. En effet, la plasticité de la phénologie des émergences, liée à une faible mobilité des jeunes qui sortent du nid et leur utilisation du milieu, nous oblige à revoir nos considérations de gestion de ces habitats, tout du moins dans le contexte particulier (édaphique, climatique et météorologique) de la Brenne. L’étude des populations par la qualité des eaux nous apporte des premiers résultats, notamment sur la présence de mercure à des doses connues pour causer des troubles chez d’autres groupes d’espèces. L’origine de ce mercure ne semble pas imputable aux activités humaines locales, mais il semble issu du cycle global du mercure et une entrée dans la chaîne alimentaire liée à la gestion par les assecs réguliers. Sans avoir démontré d’impact sur la reproduction des cistudes, nous avons mis en évidence une corrélation qui incite à porter une attention à ce phénomène de présence de mercure dans les organismes vivants des étangs de Brenne. La présence d’algues sur les tortues aquatiques est connue depuis longtemps. Toutefois, nos résultats mettent en évidence une phénologie du recouvrement de la carapace différente selon les classes d’âge et les sexes. La modification des pratiques piscicoles, vers une intensification, apparait comme le facteur agissant sur la présence et la colonisation des cistudes par les algues, par une eutrophisation des milieux (étangs). De même que pour le mercure, bien que nous ayons mis en évidence des corrélations entre la couverture algale et la condition corporelle des femelles ou encore leur capacité de reproduction, ces premiers résultats sont à poursuivre afin de connaitre l’impact à long terme sur cette espèce longévive. En Brenne, les populations de cistudes sont encore importantes mais des variables telles que le taux de juvéniles dans les populations, la présence de mercure, le recouvrement parfois très important en algues, doivent nous inciter à maintenir notre vigilance pour cette espèce, et poursuivre le travail dans le cadre de la biologie de la conservation. Ceci accompagné de valorisations et de partages de ces connaissances et des expériences de gestion
“Brenne” is a French wetland area which shelters a remarkable biodiversity and many emblematic species, among which the European pond turtle Emys orbicularis is particularly abundant. This species has been largely favored by past human activities. In Brenne, all ponds are man-made and have allowed the development, since the Middle Age, of one of the largest European pond turtle population in France. The distribution of this species has strongly decreased mainly because of changes in agricultural practices and the use of the aquatic and terrestrial environments necessary for its life cycle. Nature Reserves are important areas dedicated to the preservation of the natural heritage. One of the goal of biological conservation is to propose preservation measures based on scientific studies. E. orbicularis has been the subject of many of such studies. We choose to carry out our research on new elements for the species. First, we investigated parameters related to nesting sites: incubation under natural environment, emergence and postemergence behaviors of hatchlings. Second, we studied the populations under the prism of the quality of the aquatic environments. Generally, nesting sites were mainly considered as critical areas for egg-laying by females. However, it turns out that the use of this terrestrial habitat by the species is more important. Indeed, the plasticity of emergence phenology linked to a low mobility of hatchlings strongly suggest to change management practices of these habitats, at least in the particular context (edaphic, climate and weather) of Brenne. The study of the influence of water quality on populations allowed to highlight important patterns. Mercury levels in European pond turtle can reach doses known to cause disorders. The origin of this mercury does not seem to be linked to local human activities, but appears to originate from its global cycle. However, the Hg bioavailability is stimulated by local management practices, characterized by drainage periods. We have highlighted a correlation between the concentration of mercury and female reproduction (gravidity) which stimulates future research. A focus on algal epibiosis indicates that a large part of individuals are covered by algae. The presence of algae on aquatic turtles has been known for a long time. However, our results highlight differences of the algal epibiosis between ages and sexes. Intensive fish-farming appears to be responsible of the presence and prevalence of algae on turtles. Intensification of fish-farming practices causes an eutrophication of the environments. We also found correlations between algal cover and body condition and reproduction in adult females. These results should be pursued in order to know the long-term impact on this long-lived species. In Brenne, populations of European pond turtle are still large but some aspects such as proportion of juveniles, presence of mercury, or algal epibiosis deserve future studies in the field of conservation biology, with an emphasis on knowledge and management experiences sharing

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44

黎蓀龐 and Suen-pong Ricky Lai. "Reorganization from country management to business unit: a case study: Lai Suen Pong, Ricky." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31268912.

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Matsiras, Paul V. "PONI : an intelligent alarm system for respiratory and circulatory management in the operating rooms." Thesis, City University London, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252926.

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Heller, Jill Ann. "The effects of stock ponds on downstream potential recharge in the Arivaca Creek Watershed." Thesis, The University of Arizona, 1999. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_etd_hy0037_m_sip1_w.pdf&type=application/pdf.

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Rohrer, Alastair R. "The viability of using the stormwater ponds on the Diep River in the Constantia Valley for stormwater harvesting." Master's thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/24918.

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Harvesting stormwater to supplement water demands has attracted a growing interest in South Africa as concerns over the security of the country's water supply increase. Whilst stormwater harvesting has been shown to offer a viable alternative water resource, there are often concerns about its storage requirements due to space constraints in urban areas. Stormwater ponds offer a potential solution to these concerns. Since stormwater ponds are typically designed for the sole responsibility of attenuating the periodic peak stormwater flows that are associated with large storm events, they often remain underutilised. By introducing Real Time Control (RTC) systems to operate stormwater pond outlets, ponds could potentially be used to store stormwater. This could increase the benefits that stormwater ponds provide as well as offer a viable alternative water resource. To investigate the economic viability of harvesting stormwater from existing stormwater ponds, a case study was performed on a representative urban catchment – the Diep River subcatchment, located in Cape Town, South Africa. The catchment contains seven stormwater ponds, which could be retrofitted for harvesting purposes. Sixteen different stormwater harvesting scenarios were developed that modelled various non-potable demands in the vicinity as well as different storage and harvesting arrangements, created using RTC strategies, of the catchment's existing ponds. These scenarios were modelled using an assortment of modelling tools which include: a catchment stormwater model; water distribution network models; and a Life Cycle Cost Analysis (LCCA). The economic viability of harvesting stormwater from the Diep River subcatchment's stormwater ponds was most susceptible to the cost of the system's water distribution infrastructure. Consequently, stormwater harvesting was most economically viable if used to supply toilet, clothes washing and irrigation demands to residential properties situated in close vicinity to the system's harvesting pond as this minimised the extent of the water distribution network. The results also revealed that distributing storage amongst ponds situated throughout the catchment is an effective method of increasing the volume of stormwater a stormwater harvesting system could yield without reducing its economic viability. However, this is on the condition that the system only extracts stormwater from the most downstream pond in the catchment. Importantly, the study also revealed that the attenuation of peak flows of large storm events (up to 1-in-20 year return period), achieved when harvesting stormwater from the existing stormwater ponds would be comparable to what the ponds currently provide. The study concluded that harvesting stormwater from existing stormwater ponds is potentially viable. It also demonstrated an effective method to maximise a catchment's storage capacity using distributed storage. For stormwater harvesting to be viable however, stormwater should be used to supplement a large percentage of non-potable end-uses and requires significant uptake amongst catchment residents.

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Tharp, Rebecca. "Ecological Stormwater Management: Analysis of design components to improve understanding and performance of stormwater retention ponds." ScholarWorks @ UVM, 2018. https://scholarworks.uvm.edu/graddis/934.

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Stormwater runoff from developed land is a source of pollution and excessive flow to waterways. The most commonly employed practices for flow and volume control are stormwater ponds and basins (also referred to as detention and retention ponds). These structures can be effective at controlling peak discharge to water bodies by managing flow timing but are often ineffective at removing nutrients, particularly in dissolved forms. Pond morphology coupled with place-specific characteristics (like soil type and drainage area characteristics) may influence plant community composition in these water bodies. The interaction of physical, chemical, and biological elements in stormwater ponds may affect their water quality performance in more significant ways than previously understood. Floating treatment wetlands (FTW) are floating rafts of vegetation that can be constructed using a variety of materials and are an emerging technology aimed at improving the pollutant removal and temperature control functions of stormwater ponds. Previous studies with field research in subtropical and semiarid climatic regions found incremental nutrient removal improvement correlated with FTW coverage of pond surface area. However, data on their performance in cold climates is lacking from the literature. This dissertation presents data from a three-year study examining the performance of FTW on stormwater pond treatment potential in cold climate conditions and optimal vegetation selection based on biomass production, phosphorus (P) uptake, and root architectural characteristics that enhance entrapment functionality. To put the FTW pond performance data into context, results from a survey of seven permitted stormwater ponds in Chittenden County, Vermont and the ponds' associated variability in influential internal and external dynamics are also discussed. Pond morphology, drainage area land use, soil types, and biological communities are analyzed for correlative relationships to identify design factors that affect pond performance but are not controlled factors in stormwater system permitting.

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Ghassemzadeh, Fereshteh. "Biological and chemical features associated with salt production in solar saltfields at Dry Creek, South Australia /." Title page, contents and abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phg411.pdf.

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Odisho, Sankhero, and Nordberg Kevin Rylander. "Effekter av spelifiering : På lärplattformen PING PONG." Thesis, Högskolan i Borås, Akademin för bibliotek, information, pedagogik och IT, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-12646.

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Spelifiering definieras som användningen av speldesignelement inom icke-spelsammanhang. Detta är ett koncept vars popularitet har ökat och fortsätter att öka. På senare år har spelifiering tillämpats inom utbildning men även andra områden som: marknadsföring, politik och interaktiva system. Studier har visat märkbar inverkan av spelifiering på användares beteende men trots detta finns det en brist på tillämpningar och forskning av spelifiering på informationssystem och undervisning. Avsikten med denna studie är att redogöra för vilka känslor studenter upplever när de använder sin primära lärplattform samt hur en spelifierad lärplattform skulle påverka studenters känslor och därmed deras studieupplevelse. Detta utförs genom en kvalitativ forskningsansats som baseras på semistrukturerade intervjuer med fem studenter vilket innehar en aktiv utbildning vid Högskolan i Borås. I samband med de semistrukturerade intervjuerna presenterades en interaktiv IT-artefakt i form av en prototyp där spelelement har tillämpats på studenternas primära lärplattform. Prototypen användes för att informanterna skulle kunna få en djupare förståelse kring vad spelifiering innebär och hur det skulle kunna se ut i praktiken tillämpat vid lärplattformen. Slutsatserna som presenteras tyder på att studenters studieupplevelse förbättras till viss del då det framkommer mer positiva känslor i samband med användningen av den spelifierade lärplattformen. Detta till skillnad från vad det gjorde i samband med användningen av den primära lärplattformen där spelifiering inte var tillämpat. De positiva känslor som uppstod bland studenterna var främst en ökad motivation, ett förbättrat självförtroende och en ökad gemenskap. Vissa delar av den spelifierade lärplattformen har framkallat negativa känslor såsom stress och prestationsångest. Slutsatserna tyder även på vad man som utvecklare behöver ta i åtanke för att undvika stress och prestationsångest bland studenterna. Vi finner i övrigt att slutsatserna är väsentliga för utvecklare till följd att lyckas med en praktisk tillämpning av spelifiering på en lärplattform där studenternas studieupplevelse ligger i huvudfokus.
Gamification is defined as the use of game design elements in non-gaming context. This is a concept whose popularity has increased and continues to increase. In recent years, gamification has been applied in education but also other areas such as: marketing, politics and interactive systems. Studies have shown a noticeable impact of gamification on user behavior, but despite this, there is a lack of applications and research of gamification applied on information systems and teaching. The purpose of this study is to describe what feelings students experience when using their primary learning management system and how a gamified learning management system would affect students' feelings and thus their study experience. This is done through a qualitative research assignment that is based on semi structured interviews with five students, which holds an active education at the University of Borås. In connection with the semi structured interviews, an interactive IT artefact was presented in the form of a prototype where game elements have been applied to the students' primary learning management system. The prototype was used to enable the informants to gain a deeper understanding of what gamification involves and what it could look like in practice applied to the learning management system. The conclusions presented indicate that students' study experience is improved to some extent as there are more positive feelings in connection with the use of the gamified learning management system. This is unlike what it did in connection with the use of the primary learning management system where gamification was not applied. The positive emotions that arose among the students were primarily an increase of motivation, improved self-esteem and an increased community. Some parts of the gamified learning management system have caused negative feelings such as stress and performance anxiety. The conclusions also indicate what developers need to keep in mind in order to avoid stress and performance anxiety among the students. We also find that the conclusions are essential for developers to succeed in the practical application of gamification on a learning management system where the students' study experience is the main focus.

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Dissertations / Theses on the topic 'Pond management'

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