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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Water quality of the Muddy Creek basin

Ellison, Christopher A. January 2008 (has links)
Thesis (Ph.D.)--University of Wyoming, 2008. / Title from PDF title page (viewed on August 4, 2009). Includes bibliographical references.
82

Changing streamflow patterns in the New England region : implications for ecosystem services, water users and sustainable resources management /

Ricupero, Krista, January 2009 (has links)
Thesis (M.S.) in Civil Engineering--University of Maine, 2009. / Includes vita. Includes bibliographical references (leaves 173-177).
83

Upper Manistee River Watershed Conservation Plan prepared for the Grand Traverse Regional Land Conservancy : [a thesis submitted] in partial fulfillment ... for the degree of Master of Science in Natural Resources and Environment ... /

Kazmierski, Jonathan. January 2002 (has links)
Thesis (M.S.)--University of Michigan, 2002. / Includes bibliographical references.
84

Characterizing how fish communities and physical habitat structure are affected by urbanization in an East Tennessee watershed

Sain, Robert Lee, January 2006 (has links) (PDF)
Thesis (M.S.) -- University of Tennessee, Knoxville, 2006. / Title from title page screen (viewed on Sept. 28, 2006). Thesis advisor: John Schwartz. Vita. Includes bibliographical references.
85

Not so eerie anymore? the promise of collaborative watershed management in the Lake Erie Basin /

Hardy, Scott D., January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 169-181).
86

Using artificial tracers to observe timing of runoff from different landscape units in a small headwater catchment

Bier, Anthony Friedrich 11 1900 (has links)
Four artificial tracers were applied to a small headwater catchment in south western British Columbia to study runoff generated from topographically distinct landscape units. The seven hectare catchment is located in the University of British Columbia Malcolm Knapp Research Forest at low elevation (190-280 masl). A weir, multiple tipping bucket rain gauges and several piezometers were used to collect hydrological data. Three separate landscape units were identified based on topography, soil properties and proximity to the stream. The units included an area of shallow slope and deep soil, a riparian area along the intermittent stream channel and an area of very shallow soil with bedrock outcrops on a steep slope. Tracers used included rhodamine-WT, uranine, sodium chloride and potassium bromide. A suite of ion selective and fluorometric probes were used along with automated water sampling to monitor tracer breakthrough. The collected samples were analysed in the lab to validate the field measurements. Tracers were dissolved in solution and applied aerially with a backpack sprayer at the onset of forecasted precipitation events to facilitate rapid infiltration into the soil. The first application took place January 4th, 2006. Measurements were then taken continuously until March 20th, 2006, when a second round of tracers was applied to the landscape units. During the first measurement period, 532 mm of precipitation fell below the forest canopy over 75 days. During the second 78 day measurement period, 290 mm of rain fell. It was found that the overall wetness of the catchment affected travel times significantly. Large storms during the first, significantly wetter, application period exhibited similar lag times from peak event discharge to tracer arrival between the different landscape units. During small precipitation events and under dryer conditions, travel times were greatest in the area of shallow slope and deep soils. These lag times are indicative of longer pathways and perhaps the non-initiation of preferential flow below certain thresholds. In general, it was concluded that delineating catchments into groups of similar landscape units based on physical characteristics may be a promising new approach to explaining catchment runoff response. / Arts, Faculty of / Geography, Department of / Graduate
87

The Wolf Creek Research Basin, Yukon Territory: 26-years of hydrologic change

Chapman, Fiona M. January 2021 (has links)
Increasing temperatures and changing precipitation patterns are global consequences of climate change, which are amplified in northern environments. Cold environments are particularly sensitive to warming due to the importance of sub-zero temperatures, which influence frozen ground status and precipitation type. The objective of this research is to evaluate the controls on the timing, rate, and volume of the major hydrological fluxes within the Wolf Creek Research Basin (WCRB), Yukon Territory and to identify any long-term changes. WCRB is a long-term hydrological observatory established in 1993 to evaluate cold region hydrological processes. Within WCRB, three long-term meteorological stations at different elevations with total precipitation measurements and several stream gauges allow a long-term (26 year) evaluation of water balance components. Increases in temperature and precipitation magnitude are consistent with climate models including CIMP6 models. There has also been a significant increase in the number of high intensity precipitation days (primarily in June, July, and August). Fall and winter discharge increased and there was an increase in mean annual baseflows. The proportion of discharge output during freshet (April 1st – July 1st) has not changed, but the timing of peak flow has shifted from late-May to mid-June. This research provides a unique opportunity to study long-term change while recognizing short-term natural variability in hydrologic data. Understanding the mechanisms within catchments will allow for a stronger interpretation of the response of catchments to changing climate regimes which can have diverse impacts on local ecosystems and prevailing geohazards in northern environments. / Thesis / Master of Science (MSc) / Increasing temperatures and changing precipitation patterns are global consequences of climate change, which are amplified in northern environments. This research looks at a long-term hydrologic dataset of the Wolf Creek Research Basin (WCRB), located near Whitehorse, Yukon. Three hydrologic variables were evaluated: air temperature, precipitation, and discharge. Each variable plays a critical role in a watershed’s response to climate change. From 1993 to 2019, there was a significant increase in winter precipitation across the basin. Mean annual temperature also increased at the two lower elevation sites at a rate comparable to the rest of Yukon. Mean annual discharge has also increased, most notably in fall and winter which is reflective of an increase in groundwater contributions to the stream. This research increases our understanding of the relationships and drivers behind hydrometric changes which allows for a stronger interpretation of the response of catchments to climate change.
88

A Floristic Study of the Cal Poly Swanton Pacific Ranch and a New Combination in Sanicula crassicaulis (Apiaceae), Sanicula crassicaulis var. Nudicaulis

Kenny, Reed J 01 June 2020 (has links) (PDF)
Globally we are experiencing a biodiversity crisis and potentially a sixth mass extinction event. Plant specimens are one of the best, most concrete records of biodiversity that we can create. Despite this, the rate of plant collecting has declined steeply since World War II. Now more than ever, plant collections are vital, both for the purpose of quantifying the plant biodiversity in an area and for discovering previously unrecognized diversity. In Chapter 1, we conducted a floristic survey of the Cal Poly Swanton Pacific Ranch. The Swanton Pacific Ranch (SPR) is located north of the small town of Davenport California, in Santa Cruz county. SPR is 3,200 acres and contains areas of salt marsh, coastal bluff, coastal prairie, riparian forest, redwood forest, mixed conifer forest and chaparral in approximate ascending order of elevation. The property extends over an elevational gradient from 0 m to 420 m (1400 ft). We documented 634 taxa at SPR. In total, 974 specimens were collected during this project, 405 specimens in 2017 and 569 in 2019. We reviewed 211 historic specimens. We vouchered 546 taxa between 2017 and 2019 and observed but did not collect 6 taxa. 53 taxa are represented from historic collections and were not relocated. There are 30 taxa listed as historically present from personal observations of the authors but without vouchers. Though these do not have the same value as a physical specimen, we believe that all information is valuable and have included them with a clear indication of the source of the record. There were 465 native and 169 non-native taxa documented in the study area. There were 93 families represented, with Asteraceae, Poaceae and Fabaceae be ing the top three most speciose respectively. There were 83 taxa noted as locally rare following Neubauer, of these 16 taxa have a California Native Plant Society (CNPS) rare plant rank. We vouchered one new taxon for Santa Cruz County, Senecio aphanactis, which has a CNPS rare plant rank of 2B.2 In Chapter 2, we describe a new combination in the Sanicula crassicaulis species complex. During the project detailed in Chapter 1, we observed and collected several specimens that keyed to Sanicula crassicaulis Poepp. ex. D.C. but were notably distinct from other S. crassicaulis that we collected in the area. On further investigation, we found that these plants match the type specimen of S. nudicaulis Hook & Arn., described in 1839 and later synonymized with S. crassicaulis. This taxon is distinguished primarily by its long, sinuate marginal leaf trichomes, in contrast to the short, straight marginal trichomes of S. crassicaulis. Additionally, the length of the most proximal prickles on the schizocarps is about the same as the length of the most distal rather than the distal prickles being much longer as in S. crassicaulis and the angle of attachment of the prickles is more or less perpendicular as opposed to acute in S. crassicaulis. The known range of this taxon is between the San Francisco Bay Area and Santa Barbara County, generally near the coast. Here we recognize this taxon as a variety in S. crassicaulis, Sanicula crassicaulis var. nudicaulis. We provide a diagnosis, a map of the known range of the taxon and a key to the varieties of S. crassicaulis. Overall this project has significantly increased or knowledge and documentation of the flora of both SPR and Santa Cruz county. In addition to the immediate benefits of this study (a complete species list for SPR, the discovery of a new taxon, and the mapping of all rare species at SPR) we have also contributed almost 1,000 physical specimens to the Cal Poly Hoover herbarium which may be used in future taxonomic and ecological studies.
89

Optimization of Stormwater Management Practices and Processes

Calabrese, Mark Michael 01 April 1979 (has links) (PDF)
In recent years, stormwater has been found to be a major source of pollution to receiving waters. Major research efforts have been directed in this area, primarily as a result of the Federal Water Pollution Control Act and Public law 92-500, the 1972 Amendments to the act. Yet, a need remains for more data in the field of stormwater management. Such needs include cost-performance data and planning methodologies to optimally select best management practices (BMP's). The research culminating in this report addresses these needs. A computer program, "MANAGE", has been written to generate cost/efficiency curves, and uses these curves to optimally select a combination of management practices. The program was written in FORTRAN language and was run on the IBM 360/370 computer system. It can analyze up to 3 management practices per subwatershed and up to 20 subwatersheds in a given watershed. The optimization routine of the program utilizes a piece-wise linear approximation method in its analysis.
90

Requirements for successful irrigation systems in the Senegal River Basin (Mauritania)

Abba, Fatima Zahra 19 December 1995 (has links)
Implementation of a small-scale irrigation project in southern Mauritania is analyzed in this report. The main objective is to demonstrate that small-scale irrigation farming is the best suited solution for Mauritania's agriculture. To reach this objective different steps are taken in this study. The first step highlights the different aspects affecting the development of agriculture in the Senegal River basin such as climatic, environmental, and socio-economic constraints. The next step is the design of a small-scale irrigation system for a small region in the middle valley of the Senegal River called the Dirol plain. Finally, analysis and discussion of the design is made. This discussion centers on the problems faced during the design and the different assumptions made to implement it. The conclusion section addresses the feasibility of the design and gives recommendations that will help improve the design process for future work in the Senegal River basin. / Graduation date: 1996

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