Dissertations / Theses on the topic 'Lakes – Management'
To see the other types of publications on this topic, follow the link: Lakes – Management.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Lakes – Management.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Upadhyay, Neerja. "Management of the Lea Marston lakes." Thesis, University of Birmingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.564485.
Full textAbstract:
One of the practices for dealing with water pollution from point and non point pollution sources is the use of on-line purification lakes. The Lea Marston lakes were built in the early 1980' s to reduce the pollution load transported by the River Tame to the River Trent. The lakes operate on the principle of particle bound contaminant sedimentation. The lakes were observed to be efficient at reducing suppressed (ATU) biochemical oxygen demand (BOD(ATU)), suspended solids (SS) and metals under dry weather flow and wet weather flow conditions. However, ammoniacal-nitrogen (ammonia) is observed to increase across Lake 1. The dominant mechanism of removal is via sedimentation with greater removal occurring under higher inlet concentrations. The addition of ammonia occurs possibly via diffusion with the bed sediments providing a source of ammonia. The bed sediments were identified as a potential pollution source and processes such as diffusion and resuspension could adversely affect the water quality across Lake 1. Porewater and surface water profiles identify the significance of the bed sediments as a sink for dissolved oxygen and a source of ammonia. A modelling study showed that a River Quality Objective (RQO) of River Ecosystem Class (RE) 2 could be achieved at the lakes inlet by improvements in nearby wastewater treatment works effluent quality and water quality from the upper catchment. However, the outlet water quality would probably be adversely influenced by ammonia released from the lake sediments.
2
Morillo, Sebastian. "Engineering solutions to water quality problems in lakes." University of Western Australia. Centre for Water Research, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0153.
Full textAbstract:
Lake restoration and management strategies focus on reducing the negative impacts of enriched or polluted inflows. These strategies become of paramount importance when lakes are used for recreational and/or drinking water purposes. Long term control of eutrophication and turbidity problems associated with large inflow loads is usually oriented to catchment management. Although it has been suggested that this is the correct long term approach, public concerns usually require a short term solution. In addition, due to political and economic costs related to changes in catchment management, in-lake restoration technologies have been emerging as a viable pretreatment option, complementary to water treatment plants, both reducing the operational costs of the water treatment plant and ameliorating the water residing in the lakes. This research investigates the effects of two in-lake technologies on the dynamics of inflowing rivers, where basin shape plays a significant role. The three lakes in this study suffer from eutrophication combined with a distinctive water quality problem: from turbidity in Silvan Reservoir (Australia), to heavy metal loads in Coeur d'Alene Lake (USA) and industrial wastes in Lake Como (Italy). Firstly, the influence of basin morphology, wind speed, and wind direction on the fate and transport of two rivers flowing into the L-shaped Coeur d'Alene Lake was examined, and it was shown that transport and mixing patterns in a lake can be greatly influenced by the shape of the lake, leading to important consequences for the plankton ecology in the lake. Secondly, in Silvan Reservoir we investigated the potential to modify the basin shape using vertical barriers, increasing the retention time and hence the barrier capacity to microbial pollution. A final in-lake technology was tested for Lake Como, using a downward pointing impeller to remove polluted water from the coastal margin. Lessons from these three examples indicate that there is significant potential for in-lake remediation at relatively low cost, over relatively short timescales.
3
Chamberlain, Mary Beth. "The Creation of a Gift Shop at The Great Lakes Theater Festival." University of Akron / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=akron1318290977.
Full text
4
Wilson, Helen M. "An evaluation of alternative management strategies for shallow eutrophicated lakes and reservoirs." Thesis, University of Plymouth, 1995. http://hdl.handle.net/10026.1/1870.
Full textAbstract:
External phosphorus loadings on a range of freshwater Sites of Special Scientific Interest (SSSIs) thought to be affected by eutrophication were predicted utilising export coefficients. The effect of such loadings on lake trophic status was evaluated using the Vollenweider-OECD eutrophication model. Estimates of the relative contribution of phosphorus from various sources enabled the selection of possible reduction strategies on a site specific basis. The effect of reduction strategies on trophic status was predicted with the aid of the model. It was established that diffuse agricultural losses of phosphorus are the most common source of enrichment. However, consented discharges of sewage efHuent appear to affect a significant number of sites. Phosphorus in urban runoff is a notable source for lakes situated in less rural areas. Agricultural point sources significantly influence a small number of lakes. A critique of the methodology concluded that the use of separate export coefficients for organic and inorganic sources may be useful for identifying appropriate management strategies, but that the scientific basis for such an approach is dubious. In addition, the employment of agricultural returns for data on livestock levels may introduce an unacceptable degree of error into the calculations. The Vollenweider-OECD model appears to predict the trophic status of the lakes under assessment reasonably well, but there is a need for a reliable method of ascertaining loading reduction objectives. A review of current legislation and policy applicable to the alleviation of eutrophication of freshwater SSSIs encompassed laws relating to nature conservation, to water quality, and to agricultural extensiflcation. It confirmed that legislation which directly addresses the problem is nonexistent, but that certain laws may be applied in a piecemeal manner. In general, the form of nature conservation protection adopted in this country is not designed to prevent deterioration of water quality. An aspect of eutrophication control which may prove to be the most problematical in legislative teniis is the regulation of diffuse agricultural sources of phosphorus. Proposals for changes in law and policy on this issue included the establishment of a catchment-wide scheme, specifically designed to reduce diffuse agricultural lossesof phosphorus, and targeted at eutrophicated SSSIs.
5
Schueller, Amy M. "Modeling the sustainability of walleye populations in northern Wisconsin lakes /." Link to abstract, 2005. http://epapers.uwsp.edu/abstracts/2005/Schueller.pdf.
Full text
6
White, Arthur J. "A 1982 restoration feasibility study of Lakes of the Four Seasons in Northwestern Indiana." Virtual Press, 1985. http://liblink.bsu.edu/uhtbin/catkey/426076.
Full textAbstract:
The Lakes of the Four Seasons, a community in Lake and Porter Counties in northwestern Indiana, contains highly eutrophic lakes. A diagnostic feasibility study of the lakes was initiated in December 1981, and continued through November 1982. Morphometric, limnological and hydrologic characteristics of the lakes were defined in order to permit the development of nutrient and hydrologic budgets for the lakes. In addition to the development of these budgets, preliminary testing of a lake restoration technique, phosphorus precipitation, was performed. These studies and the resultant budgets provided necessary information for the formulation of feasible restoration methods for the lakes. The recommended restoration methods, if implemented, could enhance and maintain water quality conducive to recreational use and aesthetic enjoyment.The Lakes of the Four Seasons system has a mass water loading of 3.596 x 106 m3 Y-1and a hydraulic residence time of 0.71 y. Mass external phosphorus loading to the lakes is 537.34 kg –1 . Mass nitrogen loading to the system is 13,457 kg y -l.Big Bass Lake has a mass water loading of 2.316 x 106 m3 y-1 and a hydraulic residence time of 0.16 y. Mass external phosphorus loading to the lake is 356.76 kg y -l. Mass nitrogen loading to Big Bass Lake is 12,260 kg y -l.Lake Holiday/Lake on the Green has a mass water loading of 3.423 x 106 m3 y 1 and a hydraulic residence time of 0.65 y. Mass external phosphorus loading to the lakes is 330.52 kg y-1. Mass nitrogen loading to the Lake Holiday/Lake on the Green is 11,980 kg y1.Both loading and in-lake nitrogen:phosphorus ratios indicated phosphorus limitation in these lakes. The eutrophic condition of the lakes was also indicated by in-lake nutrient concentrations as well as excessive algal and macrophyte growth. Rapid 02 depletion, which occurs in water overlying the sediments even though the lakes are fairly well mixed, also testifies to the extreme productivity of the lakes.Restoration options for these lakes include short term cosmetic methods, longer term options for the disruption of internal phosphorus cycling, and abatement of phosphorus loading from the watershed. The cosmetic options involve the use of herbicides and algicides to give immediate relief from excessive primary productivity. Dredging and drawdown/sediment consolidation are aired at reducing internal phosphorus loading, while methods directed at the abatement of phosphorus loading from the watershed attack the cause of the lake system's problems. The longer term options necessitate further studies before implementation.
7
Sisung, Theresa. "Soil testing and nutrient application practices of agricultural retailers in the Great Lakes Region." Thesis, Kansas State University, 2016. http://hdl.handle.net/2097/32556.
Full textAbstract:
Master of AgribusinessAgricultural Economics
Terry Griffin
Agricultural runoff containing phosphorus is believed to be a major contributor of algae blooms in the Western Lake Erie Basin. However, the implementation of best management practices (BMPs) can be used to help reduce the runoff of phosphorus. This research involved conducting surveys to analyze the current implementation of BMPs in Michigan and Indiana. The hypothesis is that the survey results are similar between the two states. An additional hypothesis is that the Michigan and Indiana results are similar to results from two other studies that were previously conducted. The results from this research generally support the hypothesis that a similar number of farmers in Michigan and Indiana are already implementing best management practices on their farms. In addition to the results being similar across Michigan and Indiana, there is also some evidence that shows that the results are similar to studies from the Ohio State University (LaBarge and Prochaska 2014), CropLife magazine (Erickson and Widmar 2015) and NRCS (U.S. Department of Agriculture, Natural Resources Conservation Service 2016); however upon further investigation there are distinct differences before and after media mentions of ramifications from the Lake Erie algal blooms. While it is difficult to force farmers to implement BMPs, the results of this study may help to educate them, which may cause them to add these practices to their operations.
8
Yagbasan, Ozlem. "Modeling Of Mogan And Eymir Lakes Aquifer System." Phd thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608456/index.pdf.
Full textAbstract:
Mogan and Eymir Lakes, located 20 km south of Ankara, are important
aesthetic, recreational, and ecological resources. DikilitaS and ikizce reservoirs,
constructed on upstream surface waters, are two man-made structures in the basin
encompassing an area of 985 km2. The purpose of this study is (1) to quantify
groundwater components in lakes&rsquobudgets, (2) to assess the potential impacts of upstream reservoirs on lake levels, and (3) to determine effects of potential climatic change on lakes and groundwater levels in the basin. Available data have been used to develop a conceptual model of the system. The three dimensional groundwater model (MODFLOW) has been developed for the system. The model has been calibrated successfully under transient conditions over a period of six years using monthly periods. The results show that groundwater inflows and outflows have the lowest contribution to the overall lakes&rsquo
budget. A sensitivity analysis was conducted to determine the limits within which the regional parameters may vary. Three groundwater management scenarios had been developed. The results show that the upstream reservoirs have a significant effect on lake stages but not on groundwater levels. A trade-off curve between the amount of water released and the average stage in Lake Mogan has been developed. The continuation of the existing average conditions shows that there would be declines in groundwater elevations in areas upstream from Lake Mogan and downstream from Lake Eymir. The results also indicated that very small, but long-term changes to precipitation and temperature have the potential to cause significant declines in groundwater and lake levels.
9
West, Phillip D. "Use of Ponds and Lakes by Resident Canada Geese." W&M ScholarWorks, 2003. https://scholarworks.wm.edu/etd/1539626404.
Full text
10
Keogh, Andrew James, University of Western Sydney, of Science Technology and Environment College, and School of Engineering and Industrial Design. "Geo-chemical budget models of the Penrith Lakes Scheme." THESIS_CSTE_EID_Keogh_A.xml, 2003. http://handle.uws.edu.au:8081/1959.7/472.
Full textAbstract:
The Penrith Lakes Scheme is a series of inter-connected lakes, produced by the rehabilitation of a sand and gravel quarry, for water quality treatment and recreational uses. Presently, 5 lakes are operational comprising 4 upstream lakes for treatment of storm-water and quarry discharge and a single downstream recreational lake as the Sydney International Regatta Centre used during the Sydney 2000 Olympic Games. This report is the result of a study, during 1998-2003, with an aim to develop dynamic budget models of water, sediments and nutrients for these lakes, providing suitable data for long-term management planning and evaluation of short-term operational management.Findings showed that while progressive reassessment and refinement will be required as management control increases, the approach provides the foundation modelling procedures and frame-work for suitable hydrological and water quality management of the Penrith Lakes Scheme, and may be extended to include further lakes, water sources and management strategies.Doctor of Philosophy (PhD)
11
Grönlund, Erik. "The Recovery of Two Polluted Subarctic Lakes—Towards Nutrient Management or a Pristine State?" Mittuniversitetet, Institutionen för teknik och hållbar utveckling, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-17200.
Full textAbstract:
Two small subarctic lakes were eutrophicated due to wastewater discharge from 1964. In 1975, a wastewater treatment plant was built and a recovery process started. This paper will: (1) compile the 1972–1974, 1978–1980 and 1985–1988 investigation data regarding phosphorous and microalgae for one of the lakes; (2) complement with unpublished data from 1985 and 2003; and (3) introduce a discussion regarding three alternatives for future development of the lakes in their last phase of recovery. In the latest investigation, 2003, the lakes were assessed as almost recovered. They had returned to an oligotrophic state, but not fully to a pre-sewage situation. In the upper lake, more heavily polluted, the total phosphorous levels had decreased from an average of 168 µg P/L in 1972–1974 to an average of 12 µg P/L in 2003. The phytoplankton biomass had decreased twentyfold during the same period, from 11.2 mg/L to 0.6 mg/L. The Secchi depth had increased from 1.3 m to 2.8 m. The low oxygen level in late winter was still not recovered, thereby profoundly affecting residential organisms in the lakes. The low winter oxygen is assumed to remain so for a long time due to phosphorus release from sediments in the lakes.
12
Ingle, Beau Steven. "Collaborative Partnerships and Invasive Species Management: Filling the Voids in Management." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1366326076.
Full text
13
Simonson, Martin Albert. "Modeling Nearshore Fish Community Responses to Shoreline Types in Lake Erie." University of Toledo / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1501861205611006.
Full text
14
Anderson, Gretchen J. "Improving larval sea lamprey assessment in the Great Lakes using adaptive management and historical records." Diss., Connect to online resource - MSU authorized users, 2006.
Find full text
15
Sieracki, Jennifer L. "Spatial Modeling as a Decision-making Tool for Invasive Species Management in the Great Lakes." University of Toledo / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1408630726.
Full text
16
Leonard, Nancy Jacynthe. "Role of social network structure in the governance of Great Lakes transboundary fish stocks." Diss., Connect to online resource - MSU authorized users, 2008.
Find full text
17
Chowdhury, Gawsia Wahidunnessa. "Development and use of biological measures to assess the quality of lakes in Bangladesh." Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610508.
Full text
18
Roos, Aneri. "Perspectives of stakeholders on engagement around benefits and use of the Wilderness and Swartvlei lakes." Thesis, Nelson Mandela Metropolitan University, 2015. http://hdl.handle.net/10948/6588.
Full textAbstract:
The objective of this research was to determine how stakeholder engagement impacts on the use and sharing of ecosystem service benefits derived from large lake systems. The Wilderness and Swartvlei lake systems, which form an integral part of the Wilderness Section of the Garden Route National Park (GRNP), were chosen as the study area. The park is juxtaposed with urban and other land uses making it one of the most integrated urban conservation areas in South Africa. The park is an open-access park with only enclosed areas being the camping and chalet areas that borders onto the Touw River Estuary. A major contribution of this research was that it classified stakeholder groups into ten meta-identities (associations, businesses, charity organisations, conservancies, government departments, informal groupings, learning/educational institutions, multiple stakeholder projects, spiritual groupings and sports clubs) and that through an iterative research approach it stimulated dialogue between individuals across the various meta-identities. Engagement is a way of allowing stakeholders to develop a sense of ownership through the decision-making process. This could also lead to a higher level of trust and cooperation. The main insights drawn from this research were that, history is important; engagement is characterised by an on-going blame-game (at least in part as a result of this particular history); meta-identities share some values, but differ in how they see the world; there is a concern over social issues (widespread concern, but few mechanisms to address the issue); management agencies are stewards of the feedbacks between social and ecological systems (responsible for regulating flows of benefits), but in open-access systems cannot do so on their own; all meta-identities are keen to contribute and this can, with appropriate facilitation, be harnessed towards collective action. Stakeholders associated with all ten meta-identities identified provisioning and cultural services as a benefit derived from the lakes. No regulating or supporting services were identified as benefits. This could indicate a gap in awareness of the importance of these services. A category that emerged from this study is the importance of employment opportunities linked to the management of natural resources. The study showed that engagement does not occur around the benefits that can be derived from the lakes, but rather around the issues that have a direct or indirect influence on the ecosystem services and therefore the suite of benefits that would be available for sharing. The issues could be divided into two broad themes; social issues and developmental pressures. The social issues pose an indirect threat to the lakes while the developmental pressures pose a direct threat. As the mandates across agencies differ, with the municipalities concerned with the social issues and SANParks with the pressures, the importance of communication and cooperative governance was highlighted.
19
Jackson, Michael James. "The role of littoral macroinvertebrates in the management of the shallow lakes of the Norfolk Broads." Thesis, University of East Anglia, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273510.
Full text
20
Duveneck, Matthew Joshua. "Managing for Resistance and Resilience of Northern Great Lakes Forests to the Effects of Climate Change." PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/1551.
Full textAbstract:
Climate change is expected to drastically change the environmental conditions which forests depend. Lags in tree species movements will likely be outpaced by a more rapidly changing climate. This may result in species extirpation, a change in forest structure, and a decline in resistance and resilience (i.e., the ability to persist and recover from external perturbations, respectively). In the northern Great Lakes region of North America, an ecotone exists along the boreal-temperate transition zone where large changes in species composition exist across a climate gradient. Increasing temperatures are observed in the more southern landscapes. As climate change is expected to substantially affect mid-continental landscapes, this region is especially vulnerable to climate change. My research assessed the effects of climate change under business as usual (BAU) management as well as alternative management strategies. To do so, I simulated forest change in two landscapes (northeastern Minnesota and northern lower Michigan) under three climate change scenarios (current climate, low emissions, and high emissions), and four management scenarios (BAU, modified silviculture, expanded reserves, and climate suitable planting) with a spatially-explicit forest simulation model from year 2000 to year 2150. Specifically, I explored how climate change would affect relationships between tree species diversity and productivity; how expanded reserves and modified silviculture may affect aboveground biomass (AGB) and species diversity; how climate suitable planting may affect functional diversity, and AGB; and how alternative management may affect the resistance and resilience of forests to multiple disturbances interacting with climate change.
Under the BAU management scenario, I found that current and low emissions climate scenarios did not affect the relationship between species diversity and productivity; however, under a high emissions climate scenario, a decline in simulated productivity was coupled with a stronger positive relationship between diversity and productivity. Under the high emissions climate scenario, overall productivity declined in both landscapes with specific species declines projected for boreal species such as balsam fir (Abies balsamea) and black spruce (Picea mariana). Under alternative management scenarios, I simulated a limited ability to increase tree species and functional diversity, AGB, and net primary productivity under climate change. The limits of management were especially apparent under the high emissions climate scenario. In a novel approach to measuring resilience, I plotted the recovery of both initial species composition and AGB to stochastic fire events for each simulation. This approach assessed both a general response (i.e. AGB) with a more specific response (i.e. species composition). My results suggest that climate change will reduce the resilience of northern Great Lake forest AGB and species composition and that management effects will be largely outweighed by the declines expected due to climate change. My results highlight the necessity to consider even more innovative and creative solutions under climate change (e.g., planting species from even further south than I simulated).
21
Grund, Yuan Xiao. "Long-term Variation of Summer Phytoplankton Communities in an Urban Lake in Relation to Lake Management and Climate Conditions." PDXScholar, 2018. https://pdxscholar.library.pdx.edu/open_access_etds/4728.
Full textAbstract:
Eutrophication is one of the primary factors causing harmful cyanobacteria blooms in freshwater lakes; climate change such as warmer temperature can potentially further increase both frequency and intensity of blooms. This study investigated the long-term changes in water quality and summer phytoplankton assemblages in Oswego Lake, OR, in relation to lake management practices (e.g., hypolimnetic aeration and alum treatments), as well as climatic and regional meteorological conditions. Both water quality and phytoplankton assemblages were sampled biweekly during summer seasons between 2001 and 2013. The concentrations of total phosphorus (TP), soluble reactive phosphorus (SRP) and total nitrogen (TN) decreased 66%, 93% and 31%, respectively, in response to the hypolimnetic aeration and alum treatments since 2005. The results of summer phytoplankton assemblages showed a 62% reduction of cyanobacteria biovolume and a switch from cyanobacteria dominance (2001-2005) to diatom and chlorophyte dominance (2006-2013). Cluster analysis identified four statistically different groups of summer phytoplankton assemblages (denoted Groups 1-4). Nonmetric multidimensional scaling analysis indicated that the four groups were associated with different water quality conditions. Group 1 occurred prior to hypolimnetic aeration and was primarily comprised of cyanobacteria, associated with water conditions of high nutrients and high primary production. Group 2, dominated by cyanobacteria and chlorophytes, occurred between hypolimnetic aeration and alum surface application. Group 2 was associated with turbid water conditions. Group 3 was dominated by diatoms, occurring after alum surface application. Group 4 included R-strategist phytoplankton that quickly respond to environmental changes, occurring in the years following alum injection, drawdown and inflow alum treatment. Both Group 3 and 4 were associated with reduced nutrients in the lake. The results demonstrated a strong temporal relationship between the long-term changes in water quality and summer phytoplankton assemblages and the lake management practices. The Pacific Decadal Oscillation (PDO) index, an El-Niño-like pattern of Pacific climate variability, showed a statistically significant correlation with the summer phytoplankton dynamics, while the multivariate ENSO index (MEI) and regional meteorological variables (air temperature, rainfall, wind speed, wind direction and solar radiation) were not significantly related to the changes of phytoplankton communities during the study period. In conclusion, the study results suggest that the lake management practices had strong effects on both production and community compositions of phytoplankton, and suggest the need for a future study on large-scale climate impacts on lake ecosystems and best management practice.
22
Godbout, Lyse. "Empirical models predicting catch of brook trout (Salvelinus fontinalis) in Québec sport fishery lakes." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=75687.
Full textAbstract:
The aim of this thesis is to develop empirical models of the stable catch of brook trout in the Laurentian lakes of Quebec. Current estimators of fish yield are biased and predict poorly.A model resulting from this study shows that catch increases with fishing effort, but that the rate of increase is smaller at higher effort. For a given effort, the catch-per-unit of effort (CPUE) is greater in larger lakes. Catch is also greater in phosphorus rich lakes and smaller in acid lakes. Catch of bigger fish is associated with a lower CPUE.
No dome-shaped relationship between catch and effort, standardized for the effects of lakes characteristics, could be established. Thus the maximum sustainable yield (MSY) concept provides no guidelines for management of the fishery. However, an early warning of overexploitation is an exceptionally high rate of fishing success. In addition logistic regression based on easily obtained variables can predict the likelihood of stability of the fisheries.
23
Haines, Philip Edward, and n/a. "Physical and Chemical Behaviour and Management of Intermittently Closed and Open Lakes and Lagoons (ICOLLs) in NSW." Griffith University. School of Environmental and Applied Science, 2006. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20070221.132729.
Full textAbstract:
The term 'Intermittently Closed and Open Lake or Lagoon (ICOLL)' has been adopted in NSW to described wave dominated barrier estuaries with an intermittent connection to the ocean. ICOLLs can also be found in south east Queensland, south-west Western Australia, and some parts of Victoria and Tasmania, although they are not the dominant estuary type as in NSW. From an international perspective, ICOLLs are also found in South Africa, New Zealand, Mexico and the Atlantic coast of Brazil and Uruguay. Within NSW, ICOLLs are mostly located south of Sydney, due to the high wave activity and close proximity of the Great Dividing Range to the coast, which results in small coastal catchments and thus small fluvial and sediment runoff. The distinguishing difference between ICOLLs and other estuary types is the variable condition of their entrances, which also makes them the most sensitive type of estuary to human interference (HRC, 2002; Boyd et al., 1992). The sensitivity of ICOLLs to external inputs has been described in this thesis based on their morphometric characteristics, which includes their size, shape and predominant entrance condition. NSW ICOLLs exhibit a wide range of physical conditions. Some ICOLLs are rarely open to the ocean, while others are rarely closed. Also, some ICOLLs have experienced extensive development within their catchments, while some are located mostly or wholly within National Parks and other protected reserves. When closed, ICOLLs behave like terminal lakes, retaining and assimilating 100% of the external inputs delivered to the system. When open, tidal flushing assists with advection and dispersion of inputs, however, significant tidal attenuation across the entrance still limits opportunities for effective removal of pollutants. The majority of NSW ICOLLs are considered to be mostly closed (i.e., have a closed entrance for more than 60% of the time), while remaining ICOLLs tend to be mostly open (i.e., have a closed entrance for less than 20% of the time). Few ICOLLs have entrances that are open and closed for roughly equal proportions of time, thus resulting in a distinctive bimodal behaviour of entrance condition (i.e., mostly open or mostly closed). NSW ICOLLs tend to be mostly closed unless (i) the catchment is larger than 100km2, and/or (ii) the exposure of the entrance to ocean swell waves is less than 60 degrees and/or (iii) the entrance channel contains geomorphic controls (e.g. shallow bedrock outcrops). Unless opened artificially, ICOLLs will generally remain closed until a sufficient volume of catchment runoff accumulates within the waterway to increase water levels to a level that overtops (breaches) the entrance sand berm. Once breached, high velocity flows over the berm cause scour and the development of a formalised entrance channel, which increases exponentially until an optimum width and depth has been reached (determined by the hydrostatic head, geomorphic controls and tidal conditions at the time). Following entrance breakout and lowering of the lagoon level, sand is reworked back into the entrance under the influence of flood tides and wave processes. The environmental condition of ICOLLs has generally been assumed as being dependent on the state of the catchment and the associated input of nutrients (form and magnitude) to the system. Biogeochemical processes also are reported to influence the condition of ICOLLs, particularly denitrification, which is controlled by the organic load on the bed and the extent of benthic algae and macrophytic productivity. In addition to this, however, it is demonstrated that the predominant and prevailing entrance conditions (i.e. open or closed) also influence the physical, chemical and biological environments. ICOLLs are particularly susceptible to the impacts of future climate change. This thesis provides a description of expected impacts on NSW ICOLLs environments associated in response to future climate changes, based on a detailed appreciation of physical processes and their follow-on consequences. Impacts on ICOLLs are expected as a result of increasing sea level, altered rainfall patterns, and modified offshore wave climate. A survey of relevant government officials has revealed that more than 50% of NSW ICOLLs are artificially opened before water levels reach the height of the natural entrance sand berm. Artificial entrance opening is mostly carried out to mitigate inundation of public and/or private assets around ICOLL foreshores, such as roads, backyards, farming lands and on-site sewage (septic) systems. Truncation of the hydraulic regime of ICOLLs can modify other physical, chemical and biological processes, and can result in deleterious impacts such as the terrestrialisation of estuarine wetlands and foreshores. Few statutory environmental planning mechanisms protect ICOLLs from future degradation. This thesis has identified the key issues that potentially compromise ICOLL integrity and sustainability, which include the expected future population growth in coastal NSW (thus increasing pressure for intensification of development within ICOLL catchments), future climate change (particularly increases in sea level), and the increased demand for amenity, particularly during summer holiday periods (i.e. 'summer impacts'). A series of management models have been developed to address key issues. The models comprise a suite of strategies that target future development and existing management practices, through a range of new or modified planning instruments. Models for the future management of ICOLL entrances aim to prevent artificial openings in the long-term. This requires, however, the systematic relocation, raising or flood-proofing of public and private assets that have been established on land that is potentially subject to inundation. Increasing sea levels in the future will compound the need for improved entrance management. Pro-active, integrated and adaptive management strategies need to be implemented today to minimise the on-going conflict and potential for continued environmental degradation in the future.
24
O'Rouke, Patrick Michael. "Modeling the impacts of habitat management on largemouth bass fisheries at the Kissimmee Chain of Lakes, Florida." [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0041341.
Full text
25
Fyffe, Deanna Lynne. "Methods to Monitor Lake Erie's Harmful Algal Blooms: A Fellowship with the Cooperative Institute for Great Lakes Research." Miami University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=miami1511971289649061.
Full text
26
Makokha, J. Maende. "The role of African women in conflict resolution : a case study of the Great Lakes Region of Africa /." Abstract, 2008. http://eprints.ccsu.edu/archive/00000526/01/1975Abstr.htm.
Full textAbstract:
Thesis (M.S.) -- Central Connecticut State University, 2008.Thesis advisor: Peter A. Kyem. "... in partial fulfillment of the requirements for the degree of Master of Science in International and Area Studies." Includes bibliographical references (leaves 78-83). Abstract available via the World Wide Web.
27
Rich, Mackenzie E. "Variation in available habitat impacts the spatiotemporal interactions of a Great Lakes carnivore community." Wright State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=wright1590148657886807.
Full text
28
Kvistad, Jake T. "Modeling Ballast Water Management Strategies for Slowing the Secondary Spread of Aquatic Invasive Species on the Laurentian Great Lakes." University of Toledo / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1533328303491667.
Full text
29
Tucker, Andrew J. "The role of ultraviolet radiation in mediating warmwater fish invasion in transparent lakes." Miami University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=miami1304020369.
Full text
30
Vance, Ronald E. "Perceptions and Use: A Survey of Visitors in the Lakes Management Area, Kamas Ranger District, Wasatch-Cache National Forest, Utah." DigitalCommons@USU, 1998. https://digitalcommons.usu.edu/etd/6576.
Full textAbstract:
New planning and management paradigms for the USDA Forest Serviee suggest that future Forest Plans incorporate the best available science and the public's values into Forest Plan revisions. Revised plans should focus on the ecological capabilities of the land and how to sustain them. The means to manage the land for these outcomes should be developed with considerable and ongoing public involvement. One outcome of this public involvement can be the development of a "desired future condition" for the area being managed and the needed regulations to maintain and monitor the desired conditions.
In order to provide preliminary information on backcountry recreation in a particular setting, a survey was conducted in the Lakes Management Area (LMA) of the Kamas Ranger District in northeastern Utah. The purpose of the survey was to provide scientifically gathered baseline information (who the typical visitor
was, perceptions of and preferences for social and biophysical conditions in the LMA, how the area was being used) and to investigate the variability of visitor desires within the LMA.
Results indicate that visitors to the LMA are mostly from the nearby urban Wasatch Front. Visitors come to the LMA to relax and find solitude while hiking and camping. They report being highly satisfied with their visit, with social and biophysical conditions found during the visit surveyed largely meeting expectations or being less than expected.
The variability of visitor desires was measured by creating groupings of visitors based on characteristics of the visitor or visit considered relevant to managers. Eight groupings were developed. Subgroupings within these groups were then analyzed, using ANOVA, to determine the extent of variability within the groupings of visitors and their perceptions of and preferences for selected social and biophysical factors as well as site attributes and management options. Significant variability was found within certain groupings, particularly groupings based on the type of organization the visitor was a member of, how many previous trips to the LMA the visitor has made, and whether the visit was day use or overnight.
31
Norman, Barbara, and barbara norman@canberra edu au. "Integrated coastal management to sustainable coastal planning." RMIT University. Global Studies, Social Science and Planning, 2010. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20100304.120627.
Full textAbstract:
Integrated coastal management (ICM) has been the basis for coastal planning and management since the 1970s. The theory and practice of ICM is based on the premise that increased integration of planning and management in the coastal zone will lead to improved environmental and social outcomes for the coast. In the context of global and national trends, this thesis examines the application of ICM in three place-based coastal case studies in Victoria: the Gippsland Lakes, Point Nepean and the Geelong region. The particular focus is on the twin challenges of coastal urbanisation and the impacts of climate change. Through a wide range of applied research techniques including focus groups, the research explores the pressures, issues, impacts and implications for ICM and beyond. The case studies point to a number of important implications for ICM and identify opportunities for a more sustainable approach to coastal planning. In reviewing the research findings, a set of five steps and six principles are proposed to respond to policy failures and provide for a transition to more sustainable coastal planning in Victoria. The five steps involve expanding the theory of ICM to be outcome based and regional in its approach to coastal planning and management. In the context of climate change, a more adaptive and systems approach has been incorporated along with recognising the even greater importance of community engagement in coastal planning processes during a period of increased uncertainty and change. The principal instrument for change is a tripartite intergovernmental agreement on sustainable coastal planning underpinned by a set of six principles. These include: agreed and shared outcomes for the coastal environment to facilitate horizontal and vertical integration; an adaptive and systems approach integrating science and urban planning drawing on experience and knowledge in both disciplines; incorporation of the shared outcomes and an adaptive approach into urban and regio nal planning systems for local implementation; regional governance arrangements for integration of policy outcomes and community involvement; capacity building for sustainable coastal planning including interdisciplinary research and community education and long term monitoring and evaluation. The transition from ICM to sustainable coastal planning does not discard ICM but rather incorporates its strengths and adapts the concept to meet the twin challenges of coastal urbanisation and climate change. Further research questions are posed to indicate how the research findings could be further developed as part of a future coastal research agenda. The research findings seek to make a contribution to the theory and practice of ICM to build a pathway to coastal planning for the benefit of our coast and future generations.
32
Kane, Douglas D. "The development of a planktonic index of biotic integrity for Lake Erie." Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1092242571.
Full textAbstract:
Thesis (Ph. D.)--Ohio State University, 2004.Title from first page of PDF file. Document formatted into pages; contains xxii, 277 p.; also includes graphics. Includes bibliographical references (p. 252-277). Available online via OhioLINK's ETD Center.
33
Caldwell, Timothy J. "Effects of Climate and Water Use on the Ecology of Mountain Lakes and Rivers in the Western United States." Thesis, University of Nevada, Reno, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=13424864.
Full textAbstract:
Climate change and over-use of natural resources impacts ecosystems worldwide. Understanding physical impacts from climate and natural resource use on biological processes at multiple scales of spatial and ecological organization is needed to make useful predictions under global change scenarios. Mountain aquatic ecosystems are of particular concern because they are sensitive to climate change, represent hot spots of biodiversity, and they integrate atmospheric, terrestrial and aquatic processes into biological responses. The objective of this dissertation is to quantify physical impacts and biological responses of climate and water use on mountain aquatic ecosystems in the Western United States. In Chapter 1, I developed a data set of ice break-up dates using remote sensing techniques for mountain lakes across the Sierra and Cascade Mountain Ranges coupled with downscaled climate data to quantify drivers of lake ice phenology. I developed a predictive linear mixed effects model and used and ensemble of 15 global climate models to project changes in lake ice break-up dates through the 21st century. The results suggest that low snowpack and increased energy fluxes associated with elevated air temperatures drive earlier ice break-up dates. Projections of ice break-up show that ice break-up will be 61 ± 5 days if greenhouse gas emissions are not reduced. In Chapter 2, I analyzed specific ecological responses to earlier ice break-up dates in Castle Lake, California (a natural, sub-alpine lake). I predicted that consumer (Brook Trout; Salvelinus fontinalis) energetics and habitat use would be regulated by either climate driven water temperature or variation in food availability. The data suggest that earlier ice break-up results in a longer duration of surface water temperatures > 15 °C, coupled with decreased and increased food production in the pelagic and littoral zones, respectively. Isotopic and telemetry data showed that consumer resources and habitat use were driven by water temperature and were independent of food availability. In early ice break-up years, consumers grew less because they were thermally excluded from productive littoral zones when water temperatures were warmer for longer periods of time relative to late ice break-up years. In Chapter 3, I demonstrate that decreased streamflow in mountain rivers can reduce abundance and size structure of food supply to drift foraging Rainbow Trout (Onchorhynchus mykiss). In response to changes in streamflow and food availability, trout abandoned their energetically profitable drift foraging strategy and actively searched for prey. The shift in foraging behavior resulted in negative bioenergetic efficiencies in flow impaired sites. Taken collectively this research demonstrates that both predictable and unpredictable consequences of physical change drive biological responses across spatial gradients, ecosystem types, and levels of ecological organization.
34
Anwana, EnoAbasi D. "Forbidden (sacred) lakes and conservation : the role of indigenous beliefs in the management of wetland resources in the Niger Delta, Nigeria." Thesis, University of Greenwich, 2008. http://gala.gre.ac.uk/6099/.
Full textAbstract:
The relationship between communities of the Niger Delta and their most important wetlands was assessed with the aim of characterizing the importance of linkages between indigenous beliefs and the conservation of biodiversity. Comparative multidisciplinary studies of the belief systems and use of four freshwater lakes, one sacred and one non-sacred, in each of two communities, Biseni and Osiama in Bayelsa State, were conducted. A combination of in-depth interviews, focus group discussions, participant observation, structured questionnaires and ecological field surveys, was used. Assessment of fish biodiversity in the four lakes was conducted in conjunction with local fishermen. Results revealed a structured system of beliefs, rules and meanings within these communities which influence the communities’ use of natural resources and ensure the protection of certain reptiles, such as the threatened dwarf crocodile, Osteolaemus tetraspis. There are social sanctions and penalties for contravening the rules. Common ancestry and social connectedness among neighbouring communities link the management of some of these lakes together, forming a network of lakes reserved for periodic fishing. Measurements of fish biodiversity showed that the sacred lakes had higher diversities, as measured by both the Shannon-Weiner and Simpson-Yule indices, than the non-sacred lakes. Characiformes and Siluriformes were the predominant orders confirming observations made by fisherfolk within the study group. The culturally protected freshwater lakes studied provide insights into how biodiversity loss in the Niger Delta can be tackled through the involvement of indigenous people in the management of threatened biodiversity and watershed areas. A recommendation is made for capacity building of indigenous groups and training of common interest groups within the region for sustainable wetland resource management.
35
Torres, Angel Nolberto. "Biology, ecology, and decision rules for Carrot Weevil, Listronotus Oregonensis (Leconte) (Coleoptera: Curculionidae) management in Parsley in the Great Lakes Region /." The Ohio State University, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488205318510151.
Full text
36
Meulemans, Matthew James. "A novel approach to spatial assessments of surface water nitrate trends in selected Iowa rivers and lakes." Thesis, University of Iowa, 2019. https://ir.uiowa.edu/etd/6804.
Full textAbstract:
Overabundant nitrate in Iowa’s surface water threatens stream health, drinking water safety, and significantly contributes to hypoxic zones in the Gulf of Mexico. Researchers have quantified surface water nitrate loads historically with grab samples and, more recently, in-situ sensors. In-situ sensor networks capture changes in nitrate concentration over small time scales, providing high temporal resolution data to accurately calculate nitrate loading. However, because advanced sensors are expensive, spatial resolution is often compromised when sensors are deployed on large rivers. To collect high spatial resolution nitrate samples that complement the high temporal resolution data from in-situ sensors, we first used traditional grab samples on small, non-navigable streams in the Clear Creek and the English River watersheds. Dense grab samples across watersheds provide higher resolution data, but not at the spatial resolution achievable on navigable streams with newly developed, boat-deployed sensor technology.
We constructed a boat-deployed sensor system that automatically measured nitrate concentrations, temperature, dissolved oxygen, conductivity, and pH as we navigated a boat on a given waterbody. We used the system on the Iowa and Cedar Rivers to capture spatial and temporal changes never previously observed in Iowa. Our data suggest nitrate concentrations and yields were highest in low-relief landforms dominated by row crop agriculture. Nitrate concentrations were lower in higher-relief landforms with less row crop production.
We also measured water in Storm Lake, IA with the boat-deployed system. We measured little heterogeneity of nitrate concentrations in the lake, but observed significant nitrate reduction in a large wetland just upstream. The system captured fine scale spatial dynamics of nitrate reduction in the wetland and low nitrate concentrations throughout Storm Lake.
Our newly developed sensor platform captured high resolution water quality data, complementing the high temporal resolution data collected with in-situ sensors. High spatial resolution data in this and similar studies provide powerful insights for decision makers to target problematic areas, reduce nitrate, and improve water quality.
37
Wilson, Gregory B. "Ecosystem-Based Management of the Lake Erie Ecosystem: A Survey-Based Approach to Assessment of Management Needs." Kent State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=kent1302202900.
Full text
38
Pérez, Losada Joaquim. "A deterministic model for lake clarity; application to management of Lake Tahoe (California-Nevada), USA." Doctoral thesis, Universitat de Girona, 2001. http://hdl.handle.net/10803/7812.
Full textAbstract:
This dissertation has as its goal the quantitative evaluation of the application ofcoupled hydrodynamic, ecological and clarity models, to address the deterministic prediction of water clarity in lakes and reservoirs. Prediction of water clarity is somewhat unique, insofar as it represents the integrated and coupled effects of a broad range of individual water quality components. These include the biological components such as phytoplankton, together with the associated cycles of nutrients
that are needed to sustain their popuiations, and abiotic components such as suspended particles that may be introduced by streams, atmospheric deposition or sediment resuspension. Changes in clarity induced by either component will feed back
on the phytoplankton dynamics, as incident light also affects biological growth. Thus ability to successfully model changes in clarity will by necessity have to achieve the correct modeling of these other water quality parameters. Water clarity is also unique in that it may be one of the earliest and most easily detected wamings of the acceleration of the process of eutrophication in a water body.
39
Soltis, Jeffrey J. "Stakeholder participation in watershed permitting in the Powder River Basin of Wyoming satisfaction, success, discourse, and knowledge /." Laramie, Wyo. : University of Wyoming, 2008. http://proquest.umi.com/pqdweb?did=1686179941&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
Full text
40
Sun, Junyao. "Multi-scale effects of hydrological and landscape variables on macrophyte richness and composition in British lakes." Thesis, University of Stirling, 2016. http://hdl.handle.net/1893/25489.
Full textAbstract:
Macrophytes are an integral component of lake littoral zones and play an irreplaceable role in maintaining the ecological balance of wetlands. Recent research has highlighted the role of lake-scale environmental factors (or “filters”) and catchment- and/or landscape-scale processes in explaining variation in macrophyte communities across different scales. In this work, the effects of land-use and connectivity on macrophyte communities were explored at two contrasting spatial scales (i.e. local catchment scale and topographic catchment scale). At the local catchment scale, the results revealed strong scale-dependency. The effects of land use on macrophyte richness were most apparent at fine spatial scales (within 0.5 to 1 km) and significantly outweighed the importance of hydrology. In terms of growth form composition, the effects of hydrological connectivity were stronger than those of land use, with the greatest effect observed at an intermediate distance (~ 5 km) from the lake. The study on the hydrologically-connected lake pairs indicated that environmental filters were more influential in explaining species turnover than lake connectivity. Interestingly, geographical connectivity explained more of the variability in species turnover than hydrological connectivity. Moreover, the relative importance of environmental filters and lake connectivity to species turnover was very sensitive to the degree of human disturbance. The multi-scale interaction analyses indicated the effect of lake alkalinity on macrophyte composition is strongly influenced by catchment scale variables including hydrological features and land use intensity. The turnover in macrophyte composition in response to variability in alkalinity was stronger in catchments with low lake and stream density and weaker in catchments with a more highly developed hydrological network. Lake abiotic variables were found to have more influence on macrophyte composition in lowland catchments with a higher intensity of human disturbance. Moreover, the catchment-scale factors promoting the establishment of different communities were found to vary between catchments depending on lake type, the degree of environmental heterogeneity and hydrological connectivity.
41
Mrdjen, Igor. "Harmful Algal Blooms in Small Lakes: Causes, Health Risks, and Novel Exposure Prevention Strategies." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1531135626251706.
Full text
42
Donald, Ian R. "A preliminary assessment of the hydrodynamics of the Touw River and Wilderness Lakes system with emphasis on the management of the estuary mouth." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85775.
Full textAbstract:
Thesis (MEng)--Stellenbosch University, 2013.ENGLISH ABSTRACT: The Touw River estuary and Wilderness coastal lakes is a sensitive system from a flooding and ecological viewpoint and, therefore, careful consideration is placed on the hydrodynamics and salinity levels within the system. The estuary consists of a “temporary open/closed” estuary, where during closed mouth conditions, the sand bar at the estuary mouth is artificially managed in an attempt to reduce flood water levels in the system. The reason behind this management strategy is the construction of residential property along the flood plains of the estuary and coastal lakes, which in the past, had been exposed to regular cycles of inundation during flood events. In an attempt to reduce flood water levels in all water bodies and hence reduce the risk of inundation, a management policy was formulated. The past and present management plan is to maintain the sand bar at Touw estuary mouth, during closed mouth conditions, at an elevation of between +2.1m to +2.4m MSL, based on proposals made by the CSIR in 1981. Recent flood events, after the implementation of the management policy, still occasionally result in significant inundation of residential property, which has raised concern for some interested parties over the effectiveness of the management strategy. Furthermore, a growing concern was also evident over the long term wellbeing of the system from an ecological viewpoint. Historical data shows significant changes in salinity levels since the implementation of the management strategy which could impose negative long term effects on the system. In this study, numerical models were consequently constructed and applied in order to analyse the effectiveness of the current management policy and recalculate flood water levels under a number of proposed scenarios. Long term salinity changes were also analysed in an attempt to better understand salinity propagation throughout the system, using extreme hypothetical cases. Through the analysis of the simulation results, it was concluded that flood water levels in the Touw estuary were almost completely dependent on the size of the Touw River flood and the initial height of the sand bar at the estuary mouth. Whereas, water levels in the coastal lakes are almost entirely dependent on the quantity of runoff into the lakes and their initial water levels. The current management plan, involving only artificial manipulation of the sand bar at the estuary mouth, therefore has a fairly insignificant effect on flood water levels achieved in the coastal lakes. Furthermore, it was concluded that the construction of the preparatory channel is a vitally important aspect of the current management plan and that skimming of the sand bar alone is ineffective to completely mitigate the risk of residential inundation along the banks of the Touw River. The salinity modelling study provided a first indication of the salinity characteristics within the system. It was found that the penetration of seawater into the system was less prominent as the water bodies became further removed from the ocean and that a direct relationship was evident between the volume of direct freshwater inflow to a water body and the degree of salinity variation in that specific water body. In water bodies with high volumes of direct freshwater inflow such as the Touw estuary, a large degree of salinity variation is evident. However, in water bodies with no freshwater inflow, such as Rondevlei, salinity levels remain more stable and are less likely to fluctuate.
AFRIKAANSE OPSOMMING: Uit ‘n vloed- en ekologiese oogpunt is die Touwsriviermonding en Wilderniskusmere ‘n uiters sensitiewe stelsel en daar is dus deeglike oorweging gegee aan die hidrodinamika en soutvlakke in die stelsel. Die monding bestaan uit 'n "tydelike oop / geslote" monding, en tydens geslote mondtoestande word die sandbank by die riviermond kunsmatig beheer in 'n poging om vloedwatervlakke binne die stelsel te verminder. Die rede vir hierdie strategie is omdat baie residensiële eiendomme langs die vloedvlaktes van die monding en kusmere gebou is, wat in die verlede aan 'n gereelde siklus van oorstromings blootgestel is tydens vloede. In 'n poging om vloedwatervlakke in al die watermassas te verminder, en sodoende die risiko van oorstroming te verminder, is 'n bestuursbeleid geformuleer. In beide die vorige en die huidige bestuursplanne is die sandbank in die Touwsriviermond tydens geslote mondtoestande in stand gehou op 'n hoogte van tussen 2,1 m en 2,4 m MSL, gebaseer op die voorstelle wat deur die WNNR in 1981 gemaak is. Onlangse vloede wat plaasgevind het na die implementering van die beleid, het steeds van tyd tot tyd gelei tot noemenswaardige oorstromings van residensiële eiendomme, en kommer is uitgespreek deur 'n paar belanghebbende partye oor die doeltreffendheid van die strategie vir die bestuur. Daar is verder kommer uitgespreek oor die langtermyn welstand van die stelsel uit 'n ekologiese oogpunt. Historiese data toon 'n beduidende verandering in soutvlakke sedert die implementering van die bestuurstrategie met ‘n negatiewe langtermyn uitwerking op die stelsel. In hierdie studie is daar derhalwe numeriese modelle opgestel en toegepas ten einde die doeltreffendheid van die huidige bestuur van die beleid te bepaal, asook om die vloedvlakke te herbereken en te analiseer na aanleiding van 'n aantal voorgestelde scenario's. Langtermyn soutgehalte veranderinge is ook ontleed in 'n poging om die soutgehalte verspreiding deur die hele stelsel beter te verstaan, deur gebruik te maak van uiterste hipotetiese gevalle. Deur die ontleding van die simulasie resultate, is daar tot die gevolgtrekking gekom dat vloedwatervlakke in die Touwsrivier-monding byna heeltemal afhanklik was van die grootte van die Touwsrivier vloed en die aanvanklike hoogte van die sandbank by die riviermond. Watervlakke in die kusmere is egter byna heeltemal afhanklik van die hoeveelheid afloop na die mere en die aanvanklike watervlakke. Die huidige bestuursplan, wat slegs ‘n kunsmatige manipulasie van die sandbank by die riviermond behels, het dus 'n redelik onbeduidend invloed op die vloedwatervlakke wat in die kusmere bereik is. Daar is verder tot die gevolgtrekking gekom dat die konstruksie van die voorbereidende kanaal 'n uiters belangrike aspek van die huidige bestuursplan is, en dat die afskraping van die sandbank alleen oneffektief sou wees om die risiko van residensiële oorstroming langs die oewer van die Touwsrivier uit te skakel. Die soutgehalte modelleringstudie verskaf 'n eerste aanduiding van die soutgehalte eienskappe binne die stelsel. Daar is gevind dat die penetrasie van seewater in die stelsel minder prominent was as in die watermassas verder van die see af, en dat daar 'n duidelike direkte verband is tussen die volume van die varswater wat direk invloei na 'n watermassa en die mate van soutgehalte variasie in daardie spesifieke watermassa. In watermassas waar hoë volumes varswater direk invloei soos die Touwsrivier-monding, is 'n groot mate van soutgehalte variasie sigbaar. In die watermassas waar geen varswater invloei nie, soos die Rondevlei, bly soutvlakke meer stabiel en is minder geneig om te wissel.
43
Kozel, Carrie L. "Early Feeding In Lake Trout Fry (salvelinus Namaycush) As A Mechanism For Ameliorating Thiamine Deficiency Complex." ScholarWorks @ UVM, 2017. http://scholarworks.uvm.edu/graddis/685.
Full textAbstract:
Recruitment failure of lake trout (Salvelinus namaycush) in the Great Lakes has been attributed in part to the consumption of alewife (Alosa pseudoharengus) by adult lake trout, leading to Thiamine Deficiency Complex (TDC) and early mortality in fry. The current understanding of thiamine deficiency in lake trout fry is based on information from culture and hatchery settings, which do not represent conditions fry experience in the wild and may influence the occurrence of TDC. In the wild, lake trout fry have access to zooplankton immediately following hatching; previous studies found that wild fry begin feeding before complete yolk-sac absorption. However, hatchery-raised fry are not provided with food until after yolk-sac absorption, long after the development of TDC. Zooplankton are a potential source of dietary thiamine for wild fry in the early life stages that has not previously been considered in the occurrence of thiamine deficiency. We postulated that wild-hatched fry could mitigate thiamine deficiency through early feeding on natural prey. Specifically, we hypothesized 1) feeding should increase thiamine concentrations relative to unfed fry and 2) feeding should increase survival relative to unfed fry. Feeding experiments were conducted on lake trout fry reared from eggs collected from Lake Champlain in 2014 and Cayuga Lake in 2015. A fully crossed experimental design was used to determine the effect of early feeding by lake trout fry in thiamine replete and thiamine deplete treatments before and after feeding. Overall, thiamine concentrations and survival did not significantly differ between fed and unfed fry. Thiamine concentrations increased from egg stage to hatching in both years, suggesting a potential source of thiamine, which had not previously been considered, was available to the lake trout eggs during development.
44
Stone, John V. "Public Participation in Environmental Management: Seeking Participatory Equity through Ethnographic Inquiry." [Tampa, Fla. : s.n.], 2002. http://purl.fcla.edu/fcla/etd/SFE0000031.
Full text
45
Weng, Wei [Verfasser], Tobia [Gutachter] Lakes, Fernando [Gutachter] Jaramillo, and Ilona [Gutachter] Otto. "Aerial river management for future water in the context of land use change in Amazonia / Wei Weng ; Gutachter: Tobia Lakes, Fernando Jaramillo, Ilona Otto." Berlin : Humboldt-Universität zu Berlin, 2020. http://d-nb.info/1205314067/34.
Full text
46
Wright, Sarah E. "Sample Frequency, Duration, and Spatial Representation Considerations of Great Lakes Beach Sanitary Survey Data at Three Beaches in Racine, Wisconsin." Ohio University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1416922217.
Full text
47
Banda, Jo Ann. "Temporal and Spatial Genetic Consistency of Walleye (Sander vitreus) Spawning Groups." University of Toledo / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1321498533.
Full text
48
Buckley, David, and n/a. "Sediment quality guidelines for Australian waters : a framework for development and use." University of Canberra. Resource, Environmental & Heritage Sciences, 1997. http://erl.canberra.edu.au./public/adt-AUC20060619.163639.
Full textAbstract:
The Australian and New Zealand Environment and Conservation Council (ANZECC) and the Agriculture and Resource Management Council of
Australia and New Zealand (ARMCANZ) have announced that the 1997
review of the Australian Water Quality Guidelines will include for the first time,
consideration of sediment quality guidelines. For this reason, it is timely to
review the methods for establishing such guidelines, and the manner in which
they could be used in managing the quality of sediments in Australian rivers,
lakes and drainage systems.
In this thesis, the problem of the development of sediment quality guidelines is
introduced and basic questions relating to the development of such guidelines
are addressed. The importance of sediment monitoring and sediment quality
assessment in aquatic ecosystem management is demonstrated, and the role of
sediment quality guidelines in the process of sediment quality assessment is
discussed. The arguments considered in this thesis are illustrated by specific
reference to the setting and use of sediment quality guidelines for heavy metal
contamination.
A number of physico-chemical factors (grain size distribution, pH, redox
potential, alkalinity and hardness, salinity, organic matter) can affect the
bioavailability and toxicity of contaminants in sediments, and these factors may
vary spatially and temporally within and between sediment deposits. Changes
in physico-chemical conditions as a result of natural or anthropogenic
processes may lead to major changes in bioavailability of sediment
contaminants. The variability of these physico-chemical factors has
ramifications for the way in which sediment quality guidelines are derived and
used.
Factors affecting the way in which toxicity is measured (test species chosen,
toxicological end-point measured, duration of test relative to life-cycle), and
toxicity data is interpreted, are also important to the development of useful
sediment quality guidelines. All of these factors must be taken into account in
deriving sediment quality guidelines for Australian conditions.
The large number of factors affecting the sensitivity and efficiency of sediment
quality guidelines means that a simple set of numerical guidelines, as has been
used in the past, is not appropriate. A multi-step assessment procedure will be
required.
Methods of setting sediment quality guidelines that have been used by
authorities in overseas jurisdictions were reviewed. Advantages and
disadvantages of the various methods were compared. None of the methods
used overseas has been shown to be applicable to Australian conditions. In the
absence of a suitable method for deriving Australian sediment quality guidelines
in the short term, the adoption of the Canadian Interim Sediment Quality
Guidelines as interim sediment quality guidelines for Australia is recommended.
Sediment quality guidelines need to be viewed in the context of the overall
environmental management process, of which they form an integral part. The
policy background to environmental management in Australia, and the
management frameworks that have been put in place to implement the policy,
are outlined. The AS/NZS/ISO 14000 series of standards for environmental
management systems provides a framework which is consistent with the
principles and objectives of environmental management in Australia. It
therefore provides an appropriate framework within which to develop and use
sediment quality guidelines.
Within the broad AS/NZS/ISO 14000 policy, a framework for the
development and use of sediment quality guidelines is proposed, which will
provide a technically and legally defensible basis for the management of aquatic
sediments in Australia, in the short term and long term. The proposed
framework involves the setting of Interim Sediment Quality Guidelines for
Australia, based on the best scientific knowledge currently available. The
framework recognises that the factors affecting the bioavailability and toxicity
of sediment contaminants are complex, and that the current level of knowledge
of sediment processes is incomplete. Therefore, a conservative approach to
setting guidelines is taken, and a highly sensitive guideline based on that used in
Canada, is proposed. The framework further recognises that this approach will
lead to over protection of the environment in some cases, so a "Decision
Tree" approach is taken. The "decision tree" allows the consideration of more
complex interactions than can be incorporated into simple numeric guidelines,
while attempting to simplify the assessment process. In keeping with the ISO
14000 series of standards for environmental management, the framework also
explicitly includes steps designed to ensure that monitoring data are regularly
collated, and analysed, and where necessary, guidelines are able to be updated
in light of new knowledge gleaned from the review process.
The proposed framework is appropriate to, and supportive of, the principles of
environmental management as set out in Australian Government policy
documents, inter governmental and international agreements, and legislation.
It provides a basis for the on-going collection of data suited to increasing our
understanding of the factors influencing the behaviour of contaminants in
sediments, and thereby lead to continual improvement in sediment quality
guidelines for use in Australian conditions.
49
Šubrt, Jiří. "Holásecká jezera." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226863.
Full textAbstract:
Master´s thesis deals with the study of lakes locality called Holasecka jezera in southern part of Brno. The study gives complex evaluation of present condition of the locality and closely aims at Holasecka jezera restoration, including technical and environmentally friendly measures. Restoration and construction of new water management objects is designed together with creation of nature development zones and financial evaluation of designed measures.
50
Keith, Hamish D. "Disaster management and response : a lifelines study for the Queenstown Lakes District : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Hazard and Disaster Management in the University of Canterbury /." Thesis, University of Canterbury. Department of Geological Sciences, 2008. http://hdl.handle.net/10092/2563.
Full textAbstract:
The Queenstown Lakes District is vulnerable to a number of natural hazards. These include earthquakes, mass movements, meteorological hazards and flooding. Many of the hazards that threaten the district have the potential to cause loss of life or injury and all of them have the potential to cause severe damage to homes, businesses and other infrastructure. Infrastructure and services that support life and business in the community, and that are used everyday are known as lifelines. Lifelines are generally taken for granted but are directly associated with the quality of life that we live. Lifelines include electricity, telecommunication, water supply, wastewater removal, transportation and emergency services. Following a major disaster the need for safe, effective and timely restoration of these lifeline systems is critical. This project analyses the vulnerability of lifelines with respect to natural hazards with the aim that it can be used to ensure that when a disaster occurs appropriate and efficient action is taken to minimise the impact. This thesis also attempts to raise awareness and understanding of the hazards that threaten the Queenstown Lakes District as well as emphasise the importance of lifelines and what's involved in their management. This will hopefully help readers understand the likely impacts of a disaster so that when one occurs they will not be completely caught unaware. This thesis will also hopefully entice the reader to better prepare for a disaster. Scenarios of each hazard were created based upon current scientific understanding and are used to illustrate more clearly the priorities that need to be addressed during the response and recovery phases of a disaster.