Physical Sciences and Mathematics Commons^™

Seedling Emergence And Growth Of Mangrove Avicennia Marina (Forssk.) Vierh. Under Different Environmental Conditions In The United Arab Emirates, Abdulrazzaq Abdulla Abdulla Anwahi

Theses

Seedling emergence, survival and growth of gray mangrove Avicennia marina (Forssk.) vierh. were studied in relation to different environmental factors through a series of experiments conducted at indoor low temperature, outdoor shaded and field areas at the Marine Resources Research Center, Umm Al Qaiwain. No emergence occurred when seeds were sowed in salinities equal to or higher than 60 ppt. Seedling survival rate decreased with increasing salinity at both indoor and outdoor experimental sites . Faster seedling growth rates were observed under outdoor shaded conditions than under indoor low temperatures. Results of field studies on a sloping beach indicated that …

The Pollution Effects Of Pleasure/Work Boat Sewage Discharges On Fecal Contamination Levels Of Waters In And Around Marinas And Other Places Where Boats Are Moored On The Eastern Shore Of Virginia, George H. Bangs

Community & Environmental Health Theses & Dissertations

Contamination of seafood harvested from and recreational areas of the Chesapeake Bay, its tributaries and the Atlantic coast inshore waters may cause health problems for people consuming the seafood or coming in contact with the waters by swimming, water skiing, or other water sports. These health problems include, but not limited to, dysentery, typhoid and hepatitis (Natchez, 1990). This is a preliminary study into the level of fecal pollution generated by sewage discharges from boats in marinas and other places where boats are moored on the Eastern Shore of Virginia. Sites selected for the study included; (I) marinas and other …

Drip Irrigation, An Adaptive Strategy, Heather A. Grant Digeorge

UNLV Theses, Dissertations, Professional Papers, and Capstones

Adaptation has always played a role in the survival of man. In today's Southwest we are quickly approaching a water shortage. Agriculture is the second largest user of water. One way to save water is by conservation. Drip irrigation would save vast amounts of water currently lost to inefficiency. Drip irrigation will become an option in the adaptation in agriculture.

Continuous Monitoring Of Volatile Organic Compounds In Air Emission Using Membrane Extraction Microtrap Gc System, Xin Zhang

Theses

A novel method for continuous monitoring volatile organic compounds (VOCs) in air at trace level is presented. A membrane module and a microtrap were used along with gas chromatographic analysis. The membrane module consisted of a bundle of silicone rubber hollow fibers and separated the VOCs from the gaseous stream. The microtrap which is a very small adsorbent trap played the roles of preconcentrator and injector. The VOCs selectively permeate across the membrane into a strip gas in the membrane module. Before entering the GC column, the VOCs are trapped and concentrated by the microtrap. Desorption of the VOCs is …

Determining Recreational Visitor Carrying Capacity: The Case Of Black Canyon At Lake Mead National Recreation Area, Kenneth C. Forman

UNLV Theses, Dissertations, Professional Papers, and Capstones

Lake Mead and Lake Mohave, created by Hoover and Davis Dams respectively, were combined, along with much of the surrounding area, into the Lake Mead National Recreation Area in 1964. The enabling legislation is specific about the duty the National Park Service has to the public to create and maintain this, and other, national recreation areas for the benefit of the visitors, the environment, and future generations. By investigating human impacts on the physical environment (water quality, litter, etc.) and by querying park users on their opinions (with respect to crowding, visitor behavior, etc.), insight can be gained about appropriate …

How Effective Has The Air Force Been In Eliminating Its Dependence On Ozone Depleting Chemicals?, L. Susan Willard

Theses and Dissertations

This research was undertaken to determine how effectively the Air Force had eliminated its dependence on Ozone Depleting Chemicals. The research was limited to analyzing the impact of ODCs on major acquisition programs. Results indicated existing variables which may be impeding full implementation. Also identified were lessons learned which could be applied to future environmental legislation with potential impact on acquisition programs. In- depth telephonic interviews were conducted with Program Directors responsible for the development and fielding of major Air Force acquisition programs. Analysis revealed that ODCs substantially impacted the acquisition programs to the extent that many programs had classified …

Coherence And Usability Of An Environmental Impact Statement, Jill A. Easterly

Theses and Dissertations

The purpose of this research effort was to investigate the application of certain principles of effective communication to improve the comprehension, and ultimately the usability, of an Environmental Impact Statement (EIS). Principles from cohesion theory (an area of research describing effective design) were used to manipulate the design of select sections of two sample EISs. Each sample EIS was altered to manipulate the presence and/or absence of visual and linguistic cohesion. Subjects were required to read select versions from each section of the two sample EISs and answer four short answer questions. The dependent variables were accuracy in answering the …

Development Of An Analysis Method To Identify The Root Causes Of Finding From The Air Force Environmental Compliance Assessment And Management Program (Ecamp), Frederick B. Cade

Theses and Dissertations

The Air Force is committed to being a national leader in achieving environmental compliance. This commitment is exemplified by the Air Force Chief of Staffs goal of no 'notices of violation.' This goal, however, has proven to be elusive. In the early 1990s, the number of Air Force notices of violation (NOVs) increased by 73%, from 103 to 178. One of the reasons may be findings from the Environmental Compliance Assessment and Management Program (ECAMP) are not being utilized effectively. This research developed an analysis method to identify root causes of ECAMP findings. The model emphasized the use of performance …

Experiment Using Infrared Spectroscopy To Study The Effect Of Soil Characteristics Upon The Rate Of Trichloroethylene Desorption, Benjamin T. Kindt

Theses and Dissertations

This research investigated the influence of soil characteristics on the desorption of trichloroethylene (TCE). TCE is one of the most common contaminants at Superfund sites. Unfortunately, extraction of TCE from contaminated soils has been hindered by its slow and poorly understood desorption from soil particles. The rate and progress of desorption of TCE from seven types of soil with varying particle diameters and elemental compositions was measured using optical absorption techniques. Fitting the data to the Langmuir Isotherm functional form predicted in the literature yielded parameters for the desorption rate and total amount desorption each soil type. These parameters were …

Simulation Of Hydrologic Influences On Wetland Ecosystem Succession, Robert A. Pompilio

Theses and Dissertations

This research focuses on the development of a simulation model to determine the effects of hydrological influences on a wetland ecosystem. The model allows perturbations to the inputs of various wetland data which in turn, influences the successional development of the ecosystem. This research consisted of converting a grassland ecosystem model to one which simulates wetland conditions. The critical factor in determining the success of wetland creation is the hydrology of the system. There are four of the areas of the original model which are affected by the hydrology. The model measures the health or success of the ecosystem through …

Use Of Infrared Spectrometry To Determine The Effect Of Temperature On The Description Rates Of Trichloroethylene From Plastic Clay 98b, Abdellatif Fares

Theses and Dissertations

This thesis investigated the influence of temperature on the desorption rated of trichloroethylene (TCE) from plastic clay. It was expected that an increase in temperature will cause an increase in both the desorption rates of TCE and in the desorbed quantity. Previous studies on other chemicals indicated a faster decrease in the remaining sorbed concentration with an increase in temperature. This research made use of the infrared optical absorption technique. IR spectroscopy was used to measure the concentration of the vapor TCE that desorbed from the soil. The soil was exposed to liquid TCE for 2 days then placed inside …

A Study On The Atmospheric Quality And Control In The Emirate Of Abu Dhabi, Sukaina Faisal Al-Wasity

Theses

Limited data are available on air pollution levels in Abu Dhabi Emirate in general. Therefore, the present study was designed to investigate the level of atmospheric contaminants in the environment of Abu Dhabi Emirate. This includes measurement of suspended particulate matter less than 10 micron (SPM₁₀) in Al Ain City during normal and stormy conditions and measurement of the same air solids besides the gaseous pollutants: ozone, sulphur dioxide, carbon monoxide, nitrogen oxides and methane and non-methane hydrocarbons in Abu Dhabi City and follow up of hourly variation in their concentration. The study further includes collecting sufficient data …

Collective Interpretation Of Seismic Reflection, Gravity, Magnetic, And Resistivity Data In The Salalah Plain, Oman, For Hydrogeologic Purposes, Slyam Bin Saeed Bin Salim Ba-Awain

Theses

An interpretive geophysical study in the growing Salalah Plain, Dhofar Governate, Sultanate of Oman, was made during 1993 and part of 1994.

This investigation stems from the need to develop the main and the only water resource in this region. It is aimed to make use of the combined geophysical tools (seismic rflection, gravity, magnetics and resistivity) and available surface and borehole data to assess the environmental impact of the geophysical results.

Several seismic reflection lines were picked and interpreted; one on a horizon near the Taqah limestone (main aquifer), and the other on a horizon near the Mesozoic- Cenozoic …

Human Fetal Hemoglobin Expression And Erythrocytic Indices In Different Groups Among U.A.E Population, Fawzia Salah Ali Issa

Theses

Molecular analysis has revealed that a variety of hemoglobin molecules are produced in humans. All are tetramers consisting of numerous combinations of seven distinct polypeptide chains, each encoded by a separate gene.

Fetal hemoglobin is one of these tetramers that by eight weeks of gestation replace the embryonic hemoglobin forms. Fetal hemoglobin is the major hemoglobin in fetal life. it's concentration in blood decreases after birth to less than 2 per cent of the total hemoglobin by 6 months of age. However, in some cases fetal hemoglobin persist to synthesize in adult life in abnormal concentrations.

Our study concerned the …

Modelling Of Groundwater Flow And Pollutants Affecting Concrete Foundations, Jamil A. Gharsan Moqbil

Theses

This thesis presents a finite difference model and its associated computer program. The model has been developed for simulating the pumpage and predicting the water table fluctuations corresponding to different boundary conditions. The mathematical model solves the partial differential equation of groundwater flow by using the finite different techniques.

The model has been verified against known field measurements taken from existing wells in Al-Ain area. Water samples from these existing wells have been collected and tested in the UAE university laboratories to determine their chemical characteristics. All field data have given close results to those predicted by the model and …

Solvent Sublation Of Toluene From Aqueous Phase, Mei Chen

Theses

Solvent sublation, a surface chemical technique, was used to remove toluene from aqueous solution into a layer of paraffin oil.

Analytical methods for GC determination of toluene in both gas and aqueous phase were set up. The comparison of solvent sublation and conventional air stripping on toluene removal was carried out. It was found that solvent sublation provides significant improvement over air stripping in removing toluene from water, and reduces toluene emission to the atmosphere. The toluene emissions reduction by solvent sublation are 30%-70% under different conditions. The effects of air flowrates and thickness of organic layer were studied. Increased …

Measurement Of Oxygenated Volatile Organic Compounds Using The Thermionic Ionization Detector, Wanfang Li

Theses

A thermionic ionization detector (TID) consists of a catalytically active, low work function heated source. It responds to molecules with high electron affinity which can extract electrons from the surface of the source to form negative ions. TID has been used as selective detectors for nitrogen and phosphorous compounds (NPD). In this research, a TID has been used for selective detection of oxygenated volatile organic compounds (VOCs). The response of the TID to different oxygenated and chlorinated VOCs compounds was studied. To evaluated its performance, the analysis was done using a FID in parallel with the TID. For most of …

How Amaranth Grain Affects Total Body Weight And Major Organ Weight In The Mongolian Gerbil, Rhoshonda Montgomery- Conway

McCabe Thesis Collection

Purpose and Objectives

The purpose of this research is to determine effects of amaranth grain of the body weight and organ weight of the Mongolian gerbil. The literature research indicates that amaranth results in physiological changes that appear to be species-specific rather than general. Since the gerbil is a granivorous animal, it is hypothesized that amaranth will be completely digested and that its nutritional quality will maintain normal to increased growth. While the results of this study cannot be applied to other animals, information has been gained with regard to the influence of amaranth grain on the Mongolian gerbil.

Density And Feeding Habits Of Elk And Deer In Relation To Livestock Disturbance, Kenneth Clegg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Elk (Cervus elaphus) and mule deer (Odocoileus hemionus) density and foraging behavior were monitored in conjunction with disturbance by livestock (cattle and sheep) from 1991 to 1993 at Deseret Land and Livestock property near Woodruff, Utah. Elk and deer densities declined by as much as 92% in response to introduction of livestock, while associated areas where livestock were absent did not show this response. Biting rates and bite sizes were estimated and used to determine instantaneous intake rate. These measures were similar between pastures with cattle present or absent in 1992 but differed in 1993 for …

The Response Of Five Tropical Plant Species To Natural Solar Ultraviolet-B Radiation, Peter S. Searles

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tropical regions currently receive the highest global levels of solar ultraviolet-B radiation (UV-B, 280-320 nm) even without ozone depletion. Thus, the influence of natural, present-day UV-B irradiance in the tropics was examined for five tropical species, including three native rainforest tree species and two economically important species. Solar UV-B radiation conditions were obtained vi using either a UV-B excluding plastic film or a near-ambient UV-B transmitting film in a small clearing on Barro Colorado Island (BCI), Panama (9 ° N). Significant differences were often exhibited as increased foliar UV-B absorbing compounds, increased leaf mass per area, and reduced leaf blade …

Dungpat Microenvironmental Effects On Germination And Establishment Of Crested Wheatgrass, Ghulam Akbar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Complementary greenhouse and field studies investigated the effects of ambient environmental conditions on cattle dungpat moisture, temperature, nutrient concentration, and crust formation dynamics, which in turn influence seed germination and seedling establishment in dungpats. 'Hycrest' crested wheatgrass [Agropyron desertorum (Fisch. ex Link) X A. cristatum (L.) Gaert.] was used as a representative revegetation species.

After collecting feces from Holstein steers that had been fed crested wheatgrass seeds, uniform dungpats were prepared and placed on two soil types (loam and coarse sand) in containers under three watering treatments (field capacity, 1/2 field capacity, and no water) in the greenhouse. Dungpat …

Beaver Recolonization In South-Central Maine, Laurence Lisle Ii

Electronic Theses and Dissertations

Following a long absence due to over-trapping, beaver (Castor canadensis) recolonized most of their continental range during the middle of the 20th century. The spread of beaver across the landscape was revealed by the emergence of beaver-created wetlands, or flowages. Based on the appearance of flowages on aerial photographs from 1939, 1957, 1974, and 1991, I documented the return of beaver to a 105 km^ watershed in south-central Maine. I sought to determine if certain wetland characteristics—area, perimeter to dam length (p/d) ratio, and watershed size—influenced the order in which sites were occupied by beaver. Also, to gauge the effect …

Population Growth In North Carolina: Implications On Coastal Wastewater Management, Carol Anne Kinder

Theses and Major Papers

The sustainability of North Carolina's coastal resources are threatened from environmental degradation. A decline in water quality has resulted, in part, from a lack of regional consensus on coastal wastewater management. Yet coastal population growth continues without the necessary infrastructure to support domestic wastewater treatment. This paper will attempt to address the feasibility of an ocean outfall in the state of North Carolina by summarizing results of earlier research, drawing expertise from current outfall projects, examining legal and financial obstacles, and evaluating progressive steps toward an integrated planning of coastal wastewater disposal. Integrated Coastal Management (ICM) is one framework through …

The Speciation Of Dissolved Uranium In Marine Waters, Darrin Kent Mann

OES Theses and Dissertations

Uranium has been used extensively for quantifying geochemical processes in the marine environment. Due to its low concentration, about 3.3 μg/1, some form of preconcentration is required for analysis. The two most widely used pre-concentration schemes are co-precipitation with iron hydroxide, and chelating ion exchange chromatography. These methods were developed by following the behavior of inorganic uranium isotopes and seemed to give identical results. However, when used for trace metal analysis, these methods have been shown to extract different fractions from the same sample. Chelex-100 resin removes only inorganic or weakly bound trace metals from a solution, while the precipitates …

Estimating Groundwater Flow Parameters Using Response Surface Methodology, Leo C. Adams

Theses and Dissertations

This thesis examined the use of response surface methodology RSM as a parameter estimation technique in the field of groundwater flow modeling. Using RSM, an attempt was made to calibrate three hydraulic parameters porosity, transverse permeability, and rate of recharge of an existing two- dimensional, steady-state flow model. The model simulated groundwater flow for a portion of landfill 10 located on Wright-Patterson Air Force Base, Ohio. The model had previously been calibrated by graphical matching observed water-levels to predicted water-levels. Using the parameter values from the earlier calibration effort as a starting point, a central composite design was developed and …

Pyrolysis And Oxidation Reaction Of 1,2, Dichloroethylene In Ar; Ar And Ch4; Ar, Ch4 And O2 Mixtures, Byung Ik Park

Theses

The thermal reaction of trans-1,2-dichloroethylene (DCEE) in methane and oxygen mixtures in Ar bath gas has been studied in 10.5 mm I.D. tubular flow quartz reactors at I atmosphere pressure, isothermal temperature between 575°C and 1000°C, and times of 0.3 to 2.0 seconds.

The thermal reaction of trans-1,2-dichloroethylene in the gas phase proceeds via unimolecular HCI elimination under the reaction condition of the present experiments. The chain branching C-Cl bond fission reaction is expected to become important at the higher temperature, competing With the HCI elimination.

The decay trans- 1,2- dichloroethylene, intermediates and final product distributions varied in the absence …

Study On The Remediation Of Organic Soil Contaminated With Polychlorinated Biphenyls Using A Variable Frequency Microwave Furnace, Lili Zou

Theses

The development of new and innovative remediation technologies for soil contaminated with Polychlorinated Biphenyl (PCB) is necessary to fulfill the need of cleanup of contaminated sites. In the past eight years the Laboratory for Microwave treatment as Hazardous Substance Management Research Center has investigated the use of Microwave energy to remediate contaminated soils. A major drawback of using single frequencies of the microwave range is the non-uniformity of the electromagnetic field. In this thesis a Variable Frequency Microwave Furnace (operating between 2.40 and 7.50 GHz) is used to improve the uniformity of the field. A new method is used to …

Bio-Oxidation Of A Model Voc In Air, Jeong Seop Shim

Theses

This study was performed to find a satisfactory regime of operation for the vapor phase bio-oxidation of ethyl alcohol, a model volatile organic compound (VOC), in a specially designed bioreactor. Ethanol was selected as a model compound representing bakery oven gas pollution. A spirally wound bioreactor module was used within which was immobilized a mixed bacterial culture from aerobic sludge. The activated sludge from municipal wastewater treatment plants readily attached with no pretreatment on the surface of the spiral biosupport which is a polymeric sheet.

The parameters studied were air flow rate and inlet concentrations of ethanol. Ethanol was injected, …

Study Of The Leaching Of Pentachlorophenol From Treated Utility Poles, Jingyi Zhang

Theses

Pentachlorophenol ( PCP ) has been used as a preservative in wood industry over 40 years. If new regulations are passed, the disposal of used treated utility poles in landfills could be restricted because of the toxic properties of PCP. This study was undertaken to provide a better understanding of the rates and mechanisms of leaching of PCP from these poles.

Following the initial analytical method development for PCP determination, a study was done to apply and validate the method in a leaching characteristics study of PCP from Douglas Fir and Southern Pine.

The major factors which influence the leaching …

The Providence River Shipping Channel Dredge Project: Its Best Chance For Success Is Through Risk Communication, Elizabeth R. Deblois

Theses and Major Papers

Providence Harbor and the Providence River shipping channel in Narragansett Bay need dredging to accommodate the shipping interest of the Port of Providence. Federal and State regulations have evolved in such a way that no dredging can be initiated without identifying sites for disposal of the dredge spoils. Dredge spoils are one of the few remaining categories of materials that, under regulation, can be dumped in the ocean. What then stalemates the process of identifying dredge spoil sites and initiating a dredging program? By default Rhode Island has adopted the "do nothing" alternative for the past twenty years. This apparently …