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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.
11

Nesting of the white-faced ibis (Plegadis chihi) of Utah Lake

Kaneko, Kenichi David 18 April 1972 (has links)
Information on the nesting of the White-faced Ibis (Plegadis chihi) in Utah County is presented for the first time. Nests built in hardstem bulrush (Sciprus acutus) settled from an average height of 120.8cm on June 9 to 93.6cm on June 27, 1971. Nest spacing ranged from 2m to 9m, averaging 4.6m. Invertebrates of the class Arachnida and the insect orders Coleoptera, Homoptera, Lepidoptera, and Thysanoptera were collected in a Berlese funnel. Average clutch size was 3.17. Egg length and width averaged 51.40mm X 36.75mm. Average volume was 36.93cc. In 21 study nests, 45.8 percent of the eggs hatched, beginning on June 8 and ending on June 27. The young weighed approximately 26gm at hatching, with tarsometatarsus and bill each 15mm long. These increased to 400gm, 70mm, and 45mm, respectively, in 15 days. Feather shaft had grown to over 100mm. Major food items of the nestlings were larvae of the insect families Dytiscidae, Hydrophylidae (O. Coleoptera) and Stratiomyidae (O. Diptera). Ectoparasites collected were a louse, plegadiphilus plegadis, and three unidentified flies.
12

The distribution of Meyenia fluviatilis at Lincoln Beach area of Utah Lake with notes on seasonal occurrence of gemmules

Smith, Chadwick E. 01 August 1972 (has links)
This study of the distribution of the fresh-water sponge, Meyenia fluviatilis, at the Lincoln Beach area of Utah Lake involved the following: First, sampling of the area for the presence or absence of the species. Second, sampling at two separate areas at different depth intervals to determine if the number of sponge colonies and colony size were in any way related to depth. Finally, monthly sampling at one area to determine when gemmules of M. fluviatilis were present in the sponge colonies. Meyenia fluviatilis was found to be commonly distributed in 1-2 m of water on the lower surface of the larger rocks at 30 transects approximately 100 m apart. At the 1-2 m depth interval, the largest number of colonies (36 colonies per 50 rocks at area A and 69 colonies at area 8) were recorded. The average colony size was also greatest at this same depth (21.5 cm for area A and 26 cm for area 8). The lowest monthly percent of gemmules observed at area 8 occurred in June (22 %), while August was the highest observation with 70 %. Gemmules were observed every month and no sponge colony disintegration was observed during any month.
13

The benthic communities of the eastern rocky shore areas of Goshen Bay, Utah Lake

Toole, Thomas Whitney 01 August 1974 (has links)
Information about the benthic macroinvertebrate populations along the eastern shore of Goshen Bay, Utah Lake, Utah, can be used, in part, to determine future management of the lake. In the project herein reported, cement artificial substrate samplers were used to sample two types of substrate: rubble and compacted calcareous tufa. Monthly samples were obtained from each type of substrate from March 1972 to May 1973. An amphipod, Hyalela azteca and a chironomid, Dicrotendipes fumidus were the dominant organisms in numbers and tiomass. Amphipod numbers were dependent upon the amount of algal standing crop. Elimination of this area could affect the trophic structure of the lake by effectively reducing the macroinvertebrate population of the lake.
14

Investigations into the spawning ecology of the white bass roccus chrysops, (rafinesque) in Utah Lake, Utah

Vinvent, Frédérick 01 May 1967 (has links)
Utah Lake, located in Utah County, north-central Utah, is one of the most important natural fishing lakes in the state. The spawning ecology of the white bass (Roccus chrysops) was studied in Utah Lake between 1964 and 1966. Gill nets and seining were the primary means of sampling. The spawning location was sampled every other day throughout the spring and early summer of 1966. Three major winter schooling areas were found: Provo Bay - Creer Access south to the mouth of Spanish Fork River, Lincoln Beach, and off Ludlow Barn. There appears to be extensive winter feeding and movement among the white bass populations. Immature white bass of both sexes were found in large numbers throughout the entire lake during the summer. In the early spring months, bisexual schools of mature bass concentrated in the southern portions of the lake before forming into unisexual schools in mid-April. Spawning activities were restricted to an area adjacent to Lincoln Beach, 0.25 mile and to a depth of 60 inches. Rubble, interspersed with ledge rock and boulders, were the only bottom types selected for spawning. An area surrounding Bird Island also simulated the bottom types off Lincoln Beach, but was not utilized for spawning. Gravid females were taken in the vicinity of Lincoln Beach on May 6, 1966 when water temperatures had reached 63° F. Spawning activity lasted from 10 to 15 days in mid-June in water temperatures of 69° F. Unisexual schools of gravid females were found off Creer Access a distance of three miles from the spawning grounds. Small numbers of female bass would migrate to the spawning site, spawn, and return to the vicinity of Creer Access, never remaining over the spawning site longer than to spawn. Tributaries were not utilized for spawning, although bass were sampled feeding in the Provo River in mid-August. Turbidity of Utah Lake during the spring and summer prevented any observations of spawning activity or behavior. Summer sampling throughout Utah Lake in 1965 resulted in a 2:1 (174 males - 93 females) sex ratio. However, these figures are in conclusive as they did not include gravid females.
15

Ecology of summer aquatic invertebrate populations in a marsh area of Utah Lake

White, David A. 01 August 1963 (has links)
Mud Lake marsh lies east of Utah Lake between the cities of Provo and Springville in Utah County. Since 1936 it has become a polluted, odiferous, silted area. A study was conducted on the aquatic invertebrates during the summer of 1962 (June 19 to September 20). An .01 meter2 bottom sampler was used at 30 random stations. Each station was sampled once a week. Water depth, mud, water and air temperatures were taken at each station. Dissolved oxygen (Winkler method) and ion resistance (Wheatstone bridge) were taken each day. The aquatic invertebrate community consisted of benthic (Diptera, Oligochaeta, Nematoda), interphashic benthic (Cou{ri}xidae) and planktonic (microcrustacae, rotifera, algae). The benthic portion of the community was adequately sampled, the other two portions were not. Dipteran populations were: Chironomidae larvae - numerous throughout season; Tabanidae larvae - found occasionally; Tipulidae - increased in late summer; Ephydridae - increased in late summer. The Chironomidae population increased slowly until the first week in August, then increased rapidly with peaks in late August and early September. The population numbers dropped when water levels were below .5{6}mm and temperatures dropped below freezing. It is supposed that the dissolved oxygen became the limiting factor in low water levels because of heat increases in bottom temperatures as the water level dropped. An experiment with an aerated control gave experimental evidence for this hypothesis. The Oligochaet population showed no close relation to these physical factors.
16

Taxonomy and ecology of fungi imperfecti from four locations in Utah Lake, Utah Co., Utah

Hartman, Laird Max 01 May 1970 (has links)
Fungi imperfecti were cultured from water and bottom sediment samples collected at four locations of Utah Lake. These study sites included: (a) The mouth of Provo River, the largest fresh-water tributary entering Utah Lake, (b) Mud Lake, a large shallow area known for its high nitrogen content, (c) the entrance of the Spanish Fork River into the lake, a large fresh-water tributary containing wastes from industry and agricultural enterprises, (d) Jordan River, the only natural outlet of Utah Lake. One hundred and thirty-eight species of fungi imperfecti were identified. A total of 89 species were isolated from the Spanish Fork River, 107 species from Mud Lake, 82 species from the Provo River, and 60 species from the Jordan River Outlet. Species that were restricted to a particular area included, 16 from the Spanish Fork River, 17 species from Mud Lake, 7 species from the Provo River and 6 from the Jordan River Outlet. The total number of fungi cultured from each station was in a direct relationship to the percent organic matter present. Seven species of Aspergillus which are potential human and animal pathogens were identified. Potential plant pathogenic fungi identified included 22 species.
17

Application of separable programming to regional water quality management

Krishnan, Subramaniam January 2010 (has links)
Digitized by Kansas Correctional Industries
18

Characterizing the Fate and Mobility of Phosphorus in Utah Lake Sediments

Randall, Matthew Chambers 01 August 2017 (has links)
An increasing number of lakes worldwide are impacted by eutrophication and harmful algal blooms due to nutrient inputs. Utah Lake is a unique eutrophic freshwater lake that is naturally shallow, turbid, and alkaline with high dissolved oxygen levels. Recently, the Utah Division of Water Quality has proposed a new limitation of phosphorus (P) loading to Utah Lake from wastewater treatment plants in an effort to mitigate eutrophication. However, reducing external P loads may not lead to immediate improvements in water quality due to the legacy pool of nutrients in lake sediments. The purpose of this study was to characterize the fate and mobility of P in Utah Lake sediments to better understand P cycling in this unique system. We analyzed P speciation, mineralogy, and binding capacity in lake sediment samples collected from 15 locations across Utah Lake. P concentrations in sediment ranged from 306 to 1894 ppm, with highest concentrations in Provo Bay near the major metropolitan area. Sequential leach tests indicate that ~25-50% of P is associated with Ca (CaCO3/ Ca10(PO4)6(OH,F,Cl)2 ≈ P) and 40-60% is associated with Fe (Fe(OOH) ≈ P). Ca-associated P was confirmed by SEM images, which showed the highest P concentrations correlating with Ca (carbonate minerals/apatite). The Ca-associated P fraction is likely immobile, but the Fe-bound P is potentially bioavailable under changing redox conditions. Batch sorption results indicate that lake sediments have a high capacity to absorb and remove P from the water column, with an average uptake of 70-96% removal over the range of 1-10 mg/L P. Mineral precipitation and sorption to bottom sediments is an efficient removal mechanism of P in Utah Lake, but a significant portion of P may be temporarily available for resuspension and cycling in surface waters. Mitigating lake eutrophication is a complex problem that goes beyond decreasing external nutrient loads to the water body and requires a better understanding in-lake P cycling.
19

Measuring and Calculating Current Atmospheric Phosphorous and Nitrogen Loadings on Utah Lake Using Field Samples, Laboratory Methods, and Statistical Analysis: Implication for Water Quality Issues

Olsen, Jacob Milton 01 April 2018 (has links)
Atmospheric nutrient loading and transport though precipitation and dry deposition is one of the least understood yet one of the most important pathways of nutrient transport into many lakes. These nutrients, phosphorus and nitrogen, are essential for aquatic life and often play major roles in algae blooms that occur in lakes and reservoirs. Often heavy algal growth intensifies a variety of water quality problems. Utah Lake may be even more susceptible to atmospheric deposition due to its large surface area to volume ratio and proximity to Great Basin dust sources. In this study, eight months of atmospheric deposition data were collected and analyzed from five locations near Utah Lake. Geospatial maps were created to show the temporal distribution of phosphorus and nitrogen. Evaluation of the atmospheric deposition results indicate that between 8 to 350 tons of total phosphorus and 46 to 460 tons of dissolved inorganic nitrogen were deposited onto the surface of Utah Lake over an eight-month period. Both estimates were based on assuming that the deposition decreased exponentially from the sampling station to the middle of the lake. The large difference results from using only samples with no visible particles or insects present to give the low estimate and all samples to give the high estimate. These nutrient loading values are very significant in that it has been estimated that only about 17 tons year-1 of phosphorus and about 200 tons year-1 of nitrogen are needed to support a eutrophic level of algal growth in Utah Lake. Atmospheric deposition was found to be a major contributor in providing a eutrophic nutrient load to Utah Lake. Further, it is likely that the actual deposition loading is much higher than 8 tons per 8 months thus indicating that deposition alone adds a eutrophic phosphorus loading to the lake. Since conditions are similar in much of the Great Basin and other areas of Western United States, this seems to be a very significant finding relative to nutrient evaluation and feasible management scenarios. The results also indicate that one might expect to see more cyanobacteria blooms (Harmful Algal Blooms) in shallow ponds in this area if atmospheric deposition is the main source of nutrients, since N to P ratios are low and thus more situations arise where a shortage of ionic nitrogen favors these nitrogen-fixing cyanobacteria.
20

Improvements of Atmospheric Deposition Sampling Procedures and Further Analysis of its Impact on Utah Lake

Barrus, Seth Michael 08 April 2021 (has links)
This study focused on Atmospheric Deposition (AD) loading on Utah Lake. Utah Lake is susceptible to Harmful Algal Blooms (HABs) because of its large surface area to volume ratio, proximity to Great Basin dust sources, and various wind patterns from close mountain ranges that blow AD towards the lake. In this study, we continued the collection and analysis of AD samples that started in 2017 and 2018, while reporting additional 2019 and 2020 data. We constructed a sampler on Utah Lake itself, which allowed us to better estimate how AD loads were distributed over the lake. An interpolation assumption was made in the previous studies that the amount of AD decreases exponentially as it passes onto the lake from the shore. Results from 5 months of Bird Island AD sampling on Utah Lake indicate that this assumption was incorrect. We performed statistical comparison tests on 2 variables: (1) the difference in AD between 2 table heights at the same site and (2) the difference in AD between a filtered sample and an unfiltered sample. We were able to statistically conclude that there was no difference in AD between 1-meter and 2-meter tall sample tables and that filtered AD samples had as much as 3 times lower concentration than unfiltered AD samples. In 2017, the total AD loading was estimated to be, on the high end, approximately 350 tons of total phosphorous (TP) and 460 tons of dissolved inorganic nitrogen (DIN) (Olsen JM, 2018). After making some changes to the interpolation methods, Joshua Reidhead in 2018 estimated AD loads of 153 tons of TP and 505 tons of DIN (Reidhead, 2019). With no changes to the 2018 sampling methods, but using an updated interpolation method, we determined the AD results for Utah Lake in 2019 to be 262 tons of TP and 1052 tons of DIN. After adjustments to the sampling tables, the bucket filters, and incorporating the Bird Island sampler results, we calculated the 2020 AD loading totals to be 133 tons of TP and 482 tons of DIN on the lake.

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