This dissertation works to create a clearer understanding of sustainability in water policy. Current water policy in four US cities was compared to a matrix of recommended sustainability themes that have been presented in the literature to determine the extent of which these themes have been implemented into water policy. To best analyze policy for sustainability it is necessary to look at the policy of cities that are considered sustainable. This was determined by a city’s inclusion in “Most Sustainable US Cities” lists. The two cities that best represented sustainability were Austin, TX and San Francisco, CA. The research also included cities that are not considered leaders in sustainability but are similar in demographics, population, and state; these two cities are Fort Worth, TX and San Jose, CA. Finally, the same matrix was applied to the state policy to establish how state policy influences city sustainability. The results of this study add to the current knowledge in this field as it contributes a current analysis of sustainable water policy. The final findings compile the themes into a sustainability pyramid framework of common, uncommon, and rare sustainability. It appears that the ‘sustainable’ cities have included more uncommon and rare themes than the traditional cities, while common themes are implemented across the board. Common themes are those that are traditionally associated with sustainability – themes like conservation, reuse, and reducing pollutant impact on water sources. In order increase sustainability, cities should apply more of the themes from the top of the pyramid.

It is well established that converting wastewater, a point-source of pollution, into reclaimed water makes management of nutrients more difficult. Not all service lines measure the volume of reclaimed water used by a customer, and frequently there are no restrictions on the amount of reclaimed water that is used. Nutrients applied in excess have the potential to runoff or leach through soils and contaminate surface and groundwater resources. This research attempted to determine if corresponding surface water quality monitoring sites in reclaimed service areas reflect elevated total nitrogen (TN) and total phosphorous (TP) concentrations. The Joe’s Creek Watershed in Pinellas County, FL is a highly urbanized watershed with one wastewater plant providing tertiary treatment for reclaimed water (Pinellas County Utilities Dept.) and another wastewater plant providing secondary treatment (City of St. Petersburg Water Resources Dept.). This research reviewed concentrations of TN and TP in the reclaimed water effluent for each wastewater treatment plant and at four tributary sites in the Joe’s Creek Watershed. One tributary site, Bonn Creek, is in the tertiary treated service area, another tributary site, Miles Creek, is in the secondary treated service area, and a third tributary, Joe’s Creek, provides two control sites which are both outside of reclaimed service areas. Based on the results of comparisons and statistical analyses of the 6-year period, the TN and TP concentrations of reclaimed water from the City of St. Pete Wastewater Treatment Plant (WWTP) far exceed those of the Pinellas County WWTP. The TN concentration in the reclaimed effluent from St. Pete was nine times higher than that of Pinellas County. The TP concentration was almost five times higher at St. Pete than Pinellas County. The sites within reclaimed service areas had higher concentrations of TN and TP when compared to the control sites for the same period. Miles Creek recorded the highest mean concentrations of TN and TP of the four monitoring sites. Bonn Creek recorded the second highest mean concentrations of TN and TP. Rainfall data were reviewed and results show that several monitoring dates for Miles Creek and Bonn Creek had elevated TN and TP concentrations which coincided with periods of rainfall deficit. These and other results of this research indicate a need to reconsider minimum wastewater treatment levels in urban environments in an effort to reduce nutrient pollution, as well as a need to expand watering restrictions and enforcement, and expand education of consumers about reclaimed water.

This thesis investigates the effects of co-culturing microorganisms including 37 yeast, 38 bacteria, nine diazotrophic cyanobacteria, and three fungi on biomass and lipid production in fresh- and saltwater algae. Algal lipid content was measured using Nile Red method and gravimetric techniques. Among the algal strains tested, freshwater Coelastrum sp. 46-4, and saltwater Cricosphaera sp. 146-2-9, showed enhanced biomass yield and lipid content in response to co-culture with bacteria, cyanobacteria, and fungi. While co-culture with yeast caused inhibition of algal productivity, no difference in algal productivity was observed between nitrogen-free diazotrophic cyanobacterial co-culture and nitrogen-replete monoalgal culture. Results indicated that extracellular compounds from the freshwater bacteria Pseudomonas stutzeri and marine fungus Fusarium sp. significantly account for stimulation of lipid accumulation within algal cells, while co-cultivation with live microorganism cells stimulated biomass production in algae.

Arboricultural work is inherently dangerous, with more serious injuries and fatalities than most other professions. Safety standards exist in some jurisdictions, but it is unclear how many standards exist, how they compare to one another, and whether (and how many) jurisdictions share standards. To establish a baseline understanding of these issues, my objectives were to (i) develop a database of existing standards, (ii) identify the most frequently occurring safety topics and (iii) describe similarities and differences in safety topics among standards from different countries. I worked with a variety of contacts and traditional university library resources to identify, obtain, analyze, and compare arboricultural safety standards from around the world. I established a database of standards and found that various types of standards exist among countries: most countries used locally developed standards and industry standards were the most common types of standards because of industry professional’s expertise in arboricultural work safety matters. I analyzed the contents of 4 areas of arboricultural work categories in standards: General safety requirements (GSR), personal protective equipment (PPE), chainsaw (CS) and tree climbing (TC). GSR and PPE categories had the most proportion of common safety topics as compared to CS and TC. I identified most common safety topics in all 4 categories which shed light onto some of the areas of safety practices which are commonly recognized as important, while least common safety topics suggest areas of arboricultural work that may or may not be useful in future revisions of standards. There were 7 groups of countries most similar in the types of standards which they use, suggesting that countries can influence one another in adopting safety practices and that there are regional and international cooperation between countries in developing standards. My findings can be used by safety committees around the world in developing standards, as well as for the ISA’s International Safety Committee (ISC) to initiate an international safety standard. This study is novel and a stepping-stone for future research in evaluating the effectiveness of standards in reducing arboricultural work incident rates.

Water shortage, water contamination, and the emerging challenges in sustainable water resources management (e.g., the likely impacts of climate change and population growth) necessitate adopting a reverse logistics approach, which is the process of moving wastewater from its typical final destination back to the water supply chain for reuse purposes. This practice not only reduces the negative impacts of wastewater on the environment, but also provides an alternative to withdrawal from natural water resources, forming a closed-loop water supply chain. However, the design of such a supply chain requires an appropriate sustainability assessment, which simultaneously accounts for economic, environmental, and social dimensions. The overall aim of this work was therefore to contribute to the literature by evaluating the impacts of water reclamation and reuse according to the triple-bottom-line sustainability indicators (i.e., economic, environmental, and social) and to develop frameworks and mathematical models to help decision-makers, stakeholders, and officials with the design of sustainable water reclamation and reuse systems. The applicability of the developed frameworks and models was examined using real case studies and hypothetical scenario analyses. This enactment also revealed the tradeoffs and thresholds associated with the design of sustainable water reclamation and reuse systems. To conquer the mentioned goal, the research was conducted in three major sections. The first part of the research was outlined to design possible scenarios for water reuse based on water reuse guidelines and evaluate the different types of end-use based on the three major dimensions of sustainability (i.e., economic, environmental and social aspects), simultaneously. The different reuse types considered include unrestricted urban reuse, agricultural reuse, indirect potable reuse (IPR), direct potable reuse (DPR), distributed unrestricted urban reuse, as well as some degree of decentralization of treatment plants for distributed unrestricted urban reuse. The tradeoff investigation and decision-making framework were demonstrated in a case study and a regret-based model was adopted as the support tool for multi-criteria decision-making. This study revealed that although increasing the degree of treatment for water reuse required implementation of advanced treatment options and it increased the implementation, operation, and maintenance (O&M) costs of the design, it increased the value of resource recovery significantly, such that it can offset the capital and O&M costs associated with the treatment and distribution for DPR. Improving the reclaimed water quality also reduced the environmental footprint (eutrophication) to almost 50% for DPR compared to the other reuse scenarios. This study revealed that the distance between the water reclamation facility and the end use plays a significant role in economic and environmental (carbon footprint) indicators. In the second part of this research, a multi-objective optimization model was developed to minimize the costs and environmental footprint (greenhouse gas emissions), and maximize social benefits (value of resource recovery) of the water reclamation systems by locating the treatment facility, allocating treatment capacity, selecting treatment technology, and allocating customers (final reclaimed water users). The expansion of the water reclamation system in Hillsborough County, Florida was evaluated to illustrate the use of the model. The impacts of population density and topography (elevation variation) of the water service area on the model outputs were also investigated. Although the centralization of treatment facilities takes advantage of the economies of scale, the results revealed that simultaneous consideration of economic and environmental indicators favored decentralization of treatment facilities in the study area. This was mainly due to the significant decrease in water transfer requirements, especially in less populous areas. Moreover, the results revealed that contribution of population density to the optimal degree of decentralization of treatment facilities was significant. In the last part of this work, hypothetical scenarios for a water service area were generated to evaluate the impacts of external variables on the design of water reclamation and reuse systems. Although the conducted sensitivity analyses in the previous sections revealed the tradeoffs and thresholds associated with the design of water reclamation systems, the concept of a hypothetical study helped with the elimination of case-specific factors and local conditions that could possibly influenced the outcomes. These factors, which were specific to the case studies (e.g., the location of candidate sites for implementation of water reclamation facilities and special population distribution patters) made barriers to the conclusions and hurdled the interpretation of findings. Two major factors, which were found to be significant among the factors influencing the design of water systems (i.e., elevation variation and population density), were selected for the evaluation. Accordingly, three different topographies (i.e., flat region, medium elevation variation, and hilly) and three types of population density (i.e., low, medium, and high) were considered for the design of hypothetical cases and the previous model developed in the second section was modified and used to evaluate the impacts. The results revealed that although decentralization of water reclamation facilities decreases the costs and environmental impacts associated with water transfer phase (i.e., wastewater collection and reclaimed water distribution), there were tradeoffs between the impacts of decentralization of treatment plants and the benefits from economies of scale for treatment. The results showed that when the population density is high and there is moderate to high elevation variations in the water service area, decentralization of treatment facilities is the beneficiary option. However, if the population density is low, economies of scale for treatment becomes more influential and lower degrees of decentralization of treatment facilities is preferred.

The nutria (Myocastor coypus) is a semi-aquatic rodent native to South America that was introduced to the Pacific Northwest, USA, in the 1930s. Primary damage categories from this invasive species include burrowing and herbivory, resulting in habitat degradation. Nutria have become well-established in metropolitan habitats, and anecdotal information suggests the problem has increased in recent years. However, little regional research on the species has been conducted. The scope of this research, which emphasizes metropolitan habitats, includes three primary foci in relation to nutria populations in the Pacific Northwest: modeling habitat suitability, assessing activity and movement patterns, and identifying and managing negative impacts. Large-scale management of any invasive species requires understanding of the current and potential future population distribution. Cold temperatures have been assumed to be a limiting factor for the geographic distribution of nutria populations, but this assumption had not been explicitly tested. A mechanistic habitat suitability model based on winter temperatures performed well in predicting nutria distribution in the Pacific Northwest and nationally. Regional results suggest nutria currently occupy most accessible suitable habitat. However, coupling the model with future climate change data suggests a much larger suitable habitat zone regionally and nationally in the near future. Management of an invasive species on a local scale requires region-specific information about behavior patterns. Radio-telemetry tracking of local nutria populations in metropolitan habitats suggested higher diurnal activity levels than reported elsewhere. Activity areas were also on the lower end of reported nutria home ranges, suggesting the studied metropolitan wetland sites represent core habitat for nutria in the region. Comparison of two transmitter attachment methods, a neck collar and a tail mount, did not identify a clearly superior attachment method for short-term nutria behavior studies. The presence of nutria in metropolitan habitats in the Pacific Northwest necessitates the need to expand the limited management techniques available for these habitats. Standard Vexar® plastic mesh tubes very effectively mitigated nutria herbivory damage to woody vegetation live stakes planted in a metropolitan habitat restoration site. A recently developed nutria multiple-capture cage trap captured larger nutria and reduced non-target captures compared to a standard cage trap. The design of the multiple-capture trap, however, prevented multiple-capture events because small nutria escaped the trap. This research contributes substantially to previously limited information about nutria in the Pacific Northwest and resulted in several new findings. Climate change modeling provides the first evidence that nutria ranges could expand in the near future. Evaluation of new radio-telemetry methods will benefit future behavior studies. The assessment of new damage prevention tools provides more options for the management of nutria in urban habitats. Management recommendations include creating regional nutria management plans, identifying and targeting priority monitoring regions, finding key stakeholders, focusing on public education, and initiating a pilot control program. Recommendations for research include evaluating effects on native fauna, conducting disease surveys, assessing the extent of damage, continuing habitat suitability analysis, and developing population indices.

Many migratory shorebirds rely on estuaries as stop-over sites to refuel during migration, and the loss of stop-over sites is a primary threat to shorebird populations on the West Coast of the United States (e.g. Calidris alpina pacifica, C. mauri). Conservation and research has focused on the largest of these sites; however, smaller estuaries also host thousands of migratory shorebirds. Furthermore, the reasons for site selection are largely unknown. Estuarine inter-tidal microhabitats are non-uniform and both abiotic and biotic factors may serve as predictors of whether an abundance of shorebirds will use a site. I investigated shorebird site selection on broad and fine scales within Oregon estuaries. To identify factors that relate to shorebird abundance on large spatial scales, I compiled shorebird abundance data from estuaries throughout the Pacific Northwest as well as data on site quality factors. To investigate site selection on a finer scale I measured shorebird abundance, habitat characteristics, and food resources―invertebrates and a newly considered source, biofilm―within two Oregon estuaries during the fall migration period. Finally, I examined whether channels are preferentially used by foraging Calidrid shorebirds by conducting observations during the spring migration. I investigated whether channels may be superior foraging habitat possibly because prey are more abundant, are found at shallower depths, or because sediments are more penetrable (increasing the opportunity for shorebird probing) by taking infauna cores and measuring force required to probe in the sediment at channel and open mudflat sites. Among estuaries, shorebird densities in spring were best predicted by estuary size, as opposed to the amount of any one habitat. During fall migration, the amount of grassland in the surrounding watershed was also a good predictor, pointing to the probable importance of roost sites as well as feeding grounds. The amount of infauna also related to the density of shorebirds using a site. Within estuaries, shorebird distribution in the inter-tidal region was not generally predicted by prey abundance. Channels were used preferentially by shorebirds, and infauna abundance along channels was greater than in the surrounding mudflats. The more penetrable sediments of the channel also made it easier for shorebirds to probe and capture prey. Identification of these large-scale and fine-scale factors that influence site quality for migratory shorebirds will assist land and wildlife managers' efforts to protect these species.

Volcanic rocks typically have only low to moderate arsenic concentrations, none-the-less, elevated levels of arsenic in ground waters have been associated with pyroclastic and volcaniclastic rocks and sediments in many parts of the world. The potential for arsenic leaching from these deposits is particularly problematic as they often comprise important water-bearing units in volcanic terrains. However, the role that chemical and mineralogical variations play in controlling the occurrence and mobility of arsenic from pyroclastic rocks is largely unexplored. This study uses chemical and X-ray diffraction data to characterize and classify 49 samples of ash-flow tuffs, and 11 samples of tuffaceous sediments. The samples exhibit a range of devitrification and chemical weathering. Total and partial digestion, and water extractions of samples are used to determine the total, environmentally available, and readily leachable fractions of arsenic present in all tuff samples. Leaching experiments were also performed with buffered solutions to determine the influence of elevated pH levels on arsenic mobility. The 49 tuff samples have a mean arsenic content of 7.5 mg kg-1, a geometric mean arsenic content of 4.8 mg kg-1, a median arsenic content of 5.2 mg kg-1, and a maximum arsenic concentration of 81 mg kg-1. The mean and median values are 2.8 - 4.4x the average crustal abundance of 1.7 mg kg-1 (Wedepohl, 1995), and consistent with previously reported values for volcanic glasses and felsic volcanic rocks (Onishi and Sandell, 1955; Wedepohl, 1995), although the maximum arsenic content is higher than previously reported (e.g., Casentini et al., 2010; Fiantis et al., 2010; Nobel et al., 2004). In addition, the arsenic concentrations of tuffs were found to be highly heterogenous, both between and within individual units, and in some cases, individual outcrops. Results of whole rock and leachate analyses indicate that there is no significant difference in the total arsenic content of tuffs as a result of devitrification or weathering, but both devitrified and weathered tuffs contain higher levels of environmentally available arsenic than unweathered glassy tuffs. Glassy tuffs did not produce any readily leachable arsenic, while individual devitrified and weathered tuffs both generated aqueous concentrations that exceeded regulatory limits after 18 hours. Leaching of weathered tuffs produced higher levels of arsenic at high (~9-11) pH than in tests conducted at circum-neutral pH. Devitrified and glassy tuffs showed no increase in leachable arsenic with increasing pH. The results of this study indicate that devitrification and weathering processes determine the host phases, degree of adsorption, and overall mobility of arsenic from ash-flow tuffs. Tuffs that have undergone different types of alteration are likely to have different host phases of arsenic, and different mechanisms that mobilize arsenic into the environment. Potential host phases and mobility mechanisms are discussed, and a conceptual model of arsenic behavior in ash-flow tuffs is proposed.

Recent technological advances in unmanned observational platforms, including remotely operated vehicles (ROVs) and small unmanned aerial systems (sUAS), have made them highly effective tools for research and monitoring within marine and coastal environments. One of the primary types of data collected by these systems is video imagery, which is often captured at an angle oblique to the Earth’s surface, rather than normal to it (e.g., downward looking). This thesis presents a newly developed suite of tools designed to digitally map oblique imagery data collected with ROV and sUAS in coastal and marine environments and quantitatively evaluates the accuracy of the resultant maps. Results indicate that maps generated from oblique imagery collected with unmanned vehicles have highly variable accuracy relative to maps generated with imagery data collected with conventional mapping platforms. These results suggest that resultant maps have the potential to match or even surpass the accuracy of maps generated with imagery data collected with conventional mapping platforms but realizing that potential is largely dependent upon careful survey design.

Marshes and seagrass beds have been widely recognized as important habitat for estuarine species, but less has been done on how these habitats interact and function together, thereby limiting understanding of the variability of juvenile recruitment to coastal systems. Therefore, the objective of this study was to assess the interaction between fringing marsh and adjacent seagrass for the provision of habitat for juvenile nekton. Weekly seine net and benthic seagrass core sampling from June to November 2020 determine the relationship between nekton and marsh-edge and seagrass habitat. This study shows disparate results, in terms of the effects of proximity to marsh edge and seagrass biomass on nekton abundance and size, pointing to different selectivity of marsh edge versus seagrass by different species. In addition, there are no effects of proximity to marsh edge and seagrass biomass on community composition, but an interactive effect on community dispersion.