This project involves developing and applying bacterial source tracking (BST) methodology to determine sources of fecal pollution in water for a rural community (Millwood, VA). Antibiotic resistance analysis (ARA) is the primary BST method for fecal source identification, followed by randomly amplified polymorphic DNA (RAPD) analysis for confirmation. Millwood consists of 66 homes, all served by individual septic systems, and a stream (Spout Run) passes through the center of the community. Spout Run drains a 5,800 ha karst topography watershed that includes large populations of livestock and wildlife. Stream and well samples were collected monthly and analyzed for fecal coliforms and fecal streptococci, starting in 5/99 and ending in 5/00. Twelve percent of the well samples and 92% of the stream samples were positive for fecal coliforms, and 26% of the stream samples exceeded the recreational water standard (1,000 fecal coliforms/100 ml). ARA of fecal streptococci recovered from the stream samples indicated that isolates of human origin appeared throughout the stream as the stream passed through Millwood with a yearly average of (approx. 10% human, 30% wildlife, and 63% livestock), and the percent human origin isolates declined downstream from Millwood. These results were obtained by comparing the antibiotic resistance profiles of stream isolates against a library of 1,174 known source isolates with correct classification rates of 94.6% for human isolates, 93.7% for livestock isolates, and 87.8% for wildlife isolates. There is a human signature in Spout Run, but it is small compared to the proportion of isolates from livestock and wildlife. The sporadic instances where well water samples were positive appeared primarily during very dry periods. Restricting livestock access to streams can dramatically lower fecal coliform counts during the unusually hot and dry periods. Reducing FC counts to below recreational water standards for Virginia (1000 per 100ml for any one sample) may be achievable, however to maintain streams below standards may prove to be difficult, as Spout Run is in an area where there are large populations of Canada geese, deer, and other wildlife, and will be hard to restrict these animals. / Master of Science

In recent years, both the state and federal governments of the United States have at last recognized erosion as a serious problem affecting the people of this land socially and economically, just as it affected the people of those kingdoms now buried in the sands of the deserts. Because of the seriousness of the problem, studies are being instituted on larger scopes than ever before and there is a greater realization of the pressing need for more adequate information about erosion, its causes, effects, prevention, and other related factors. That intense rainstorms result in higher rates of runoff is an acknowledged fact. These rates of runoff play an important part in studies made by soil conservationists, and upon their studies will depend the same success or failure of conservation practices. Soil conservationists have already espied the need for planning projects or designs that will take care of maximum runoffs which are to be expected at definite frequencies. The United States Geological Survey has collected records and made investigations of great value to engineers of navigation and flood control projects, as well as power developments and other such works which interest students of hydrology and soil conservation. Moreover, experiment stations in practically every state are cooperating with soil conservationists and soil specialists in attacking erosion problems facing the nation. The goal of all these investigations is towards finding means by which to help Nature in keeping the land so clothes that erosion may be kept within the natural limits. Hence, work is being conducted on many various problems. One particular problem upon which more information is needed is that runoff, its causes and effects in the Limestone Valley and Uplands Region in the State of Virginia. With the idea of making some contribution, therefore, that may help effect a solution by making available data for the above region, this problem was chosen as a subject for a Master’s thesis. / Master of Science

Increasing populations in urban regions have prompted the development of areas previously undisturbed. This development has spurred the formation of numerous models and methods to simulate the effects of urbanization on runoff processes. The engineer who must use these models and methods needs to be aware of their capabilities and performance. Many of the models assume that calibration will take place to improve the final results. Unfortunately, this is not the case for the majority of drainage studies. A qualitative and quantitative evaluation is made to help the engineer decide which model or method is applicable in certain situations. Simulations are performed on eight watersheds in northern Virginia. Nineteen models are evaluated and compared to gaged events as well as calibrated design storms. The models include EPA SWMM, PSRM-QUAL, TR-20, HEC-1, TR-55, variations of the rational method, three-unit hydrograph procedures, the USGS regression equations, and the Anderson method. Coverage is given for all of the models to outline their capabilities. Hydrographs are evaluated with respect to peak flow, time to peak flow, time base, volume, and overall shape. Statistical measures are introduced to quantitatively test the modeled hydrograph to a baseline reference hydrograph. The statistics yield many errors with the models being evaluated. A selection criteria is given where the models may be chosen based on their performance. The table is limited to the range of watersheds evaluated. Trends in each model toward basin area, land use condition, and general model type are discussed. A cross-calibration technique for improving the accuracy of some models is verified. / Master of Science

Orientador: João Francisco Escobedo / Banca: Valéria Cristina Rodrigues Sarnighausen / Banca: Rodrigo Máximo Sanchez Román / Banca: Paulo Andre de Oliveira / Banca: Carlos Roberto Pereira Padovani / Abstract: The objective of this research was to study air temperature and reference evapotranspiration (ETo) in the different agroecological zones of Bolivia (Plains, Valleys and Andean) using statistical and geostatistical models, with air temperature database of 235 meteorological stations in Bolivia and 41 of neighboring countries was used. The study is presented in two chapters: The first describes the characterization of the values of the medium (Tmed) maximum (Tmax) and minimum (Tmin) air temperature, through three spatial distributions: Departments, hydrographic basins and agroecological zones. Being the latter the best alternative of analysis. Linear regression analysis allowed to obtain the estimation equations for Tmed, Tmax and Tmin in function of altitude, with high determination coefficients (R2). The deviations resulting from comparisons between the seasonal and monthly equations estimated values in relation to the annual average suggest, in most altitudes, seasonal or monthly equations use, mainly for Tmed and Tmin. Were presented the spatial variations Tmed, Tmax and Tmin through isothermal maps. The maps show the strong influence of altitude on temperature values, placing higher isotherms in the Plains zone (lowlands) and lower in the Andean zone (highlands). The second chapter describes the characterization of ETo in the three agroecological zones of Bolivia, using temperature as the input variable: McGuinness - Bordne, Hargreaves - Samani and Thornthwaite. All three ... (Complete abstract click electronic access below) / Resumen: La presente investigación tuvo por objetivo estudiar la temperatura del aire y la evapotranspiración de referencia (ETo) en las diferentes zonas agroecológicas de Bolivia (Llanos, Valles y Andina) a través de modelos estadísticos y geoestadísticos, con base de datos de temperaturas del aire de 235 estaciones meteorológicas de Bolivia y 41 de países vecinos. El estudio es presentado en dos capítulos: El primero describe la caracterización de valores de la temperatura media (Tmed) máxima (Tmax) y mínima (Tmin) del aire, mediante tres distribuciones espaciales: Departamentos, cuencas hidrográficas y zonas agroecológicas. Siendo esta última la mejor alternativa de análisis. Un análisis de regresión lineal logró obtener las ecuaciones anuales que estiman la Tmed, Tmax e Tmin en función de la altitud, con elevados coeficientes de determinación (R2). Las desviaciones resultantes de comparaciones entre las ecuaciones estacionales y mensuales en relación a la media anual sugieren, en la mayoría de las altitudes, el uso de ecuaciones estacionales o mensuales, particularmente para Tmed e Tmin. Fueron presentadas las variaciones espaciales de Tmed, Tmax e Tmin por medio de mapas isotérmicas, los mapas evidencian la fuerte influencia de la altitud sobre valores de Tmed, Tmax e Tmin, marcando isotermas de valores más altos en la zona de los Llanos (zonas bajas) y, de valores más bajos en la zona Andina (zonas altas). El segundo capítulo describe la caracterización de ETo en tres zonas agro... (Resumen completo clicar acceso eletrônico abajo) / Resumo: O presente pesquisa teve por objetivo estudar a temperatura do ar e a evapotranspiração de referência (ETo) nas diferentes zonas agroecológicas da Bolívia (Lhanos, Vales e Andina) por meio de modelos estatísticos e geoestatísticos, com base de dados de temperatura do ar de 235 estações meteorológicas da Bolívia e 41 de países vizinhos. O estudo é apresentado em dois capítulos: O primeiro descreve a caracterização dos valores de temperatura média (Tmed) máxima (Tmax) e mínima (Tmin) do ar, mediante três distribuições espaciais: Departamentos, bacias hidrográficas e zonas agroecológicas, sendo esta última a melhor alternativa de análise. Uma análise de regressão linear permitiu a obtenção das equações de estimativa Tmed, Tmax e Tmin em função da altitude, com elevados coeficientes de determinação (R2). Os desvios resultantes das comparações entre os valores estimados das equações sazonais e mensais em relação à média anual sugerem, na maioria das altitudes, o uso das equações sazonais ou mensais, particularmente para Tmed e Tmin. Foram apresentados as variações espaciais da Tmed, Tmax e Tmin por meio de mapas isotérmicas. Os mapas comprovam a forte influência da altitude sobre valores de Tmed, Tmax e Tmin, colocando isotermas de valores mais altos na zona dos Lhanos (zonas baixas) e, de valores mais baixos na zona Andina (zonas altas). O segundo capítulo, descreve a caracterização da ETo nas três zonas agroecológicas da Bolívia, utilizando a temperatura como variável de entrada... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor

Spatial and temporal information on catchment sediment sources and sinks can provide an improved understanding of catchment response to human-induced disturbances. This is essential for the implementation of well-targeted catchment-management decisions. This thesis investigates the nature and timing of catchment response to human activities by examining changes in sediment sources and sinks in a dry-tropical subcatchment of the Great Barrier Reef (GBR) catchment area, in northeastern Australia. Changes in catchment sediment sources, both in terms of spatial provenance and erosion type, are determined using sediment tracing techniques. Results indicate that changes in sediment source contributions over the last 250 years can be linked directly to changes in catchment land use. Sheetwash and rill erosion from cultivated land (40-60%) and channel erosion from grazed areas (30-80%) currently contribute most sediment to the river system. Channel erosion, on a basin-wide scale, appears to be more important than previously considered in this region of Australia. Optically stimulated luminescence and 137Cs dating are used to determine pre-and post- European settlement (ca. 1850) alluvial sedimentation rates. The limitations of using 137Cs as a floodplain sediment dating tool in a low fallout environment, dominated by sediment derived from channel and cultivation sources, are identified. Low magnitude increases in post-disturbance floodplain sedimentation rates (3 to 4 times) are attributed to the naturally high sediment loads in the dry-tropics. These low increases suggest that previous predictions which reflect order of magnitude increases in post-disturbance sediment yields are likely to be overestimates. In-channel bench deposits, formed since European settlement, are common features that appear to be important stores of recently eroded material. The spatially distributed erosion/sediment yield model SedNet is applied, both with generic input parameters and locally-derived data. Outputs are evaluated against available empirically-derived data. The results suggest that previous model estimates using generic input parameters overestimate post-disturbance and underestimate predisturbance sediment yields, exaggerating the impact of European catchment disturbance. This is likely to have important implications for both local-scale and catchment-wide management scenarios in the GBR region. Suggestions for future study and the collection of important empirical data to enable more accurate model performance are made.

Water quality depends on natural conditions and use and occupation of the watershed and its knowledge is essential in the management process of recursoso water. The river is a tributary of Siriri river basin Japaratuba is an important source of water for human consumption and irrigation, and its main tributaries and rivers Siriri Vivo and Morto. Thus, this study aims to analyze through physico-chemical parameters of water quality in river basin Siriri and its seasonal variation. The monitoring was performed in 7 samples campaigns between February 2010 to November 2011, with the following parameters: temperature, pH, electrical conductivity, color, total dissolved solids, hardness, dissolved oxygen, ammonia, nitrate, nitrite, total nitrogen, phosphate, total phosphorus and chlorophyll-a. The river Siriri Vivo shows good water quality unlike Siriri Morto River, which has been indicative of eutrophication. / A qualidade da água depende das condições naturais e uso e ocupação do solo da bacia hidrográfica e o seu conhecimento é fundamental no processo de gestão dos recursoso hídricos. O rio Siriri é afluente da bacia hidrográfica do rio Japaratuba é uma importante fonte de água para abastecimento humano e irrigação, tendo como principais afluentes os rios Siriri Vivo e Morto. Desta forma ,este estudo tem o objetivo analisar através de parâmetros físico-químicos a qualidade da água da bacia hidrográfica do rio Siriri e sua variaçao sazonal. O monitoramento foi realizado em 7 campanhas de amostras entre fevereiro de 2010 a novembro de 2011, sendo avaliados os parâmetros: temperatura, pH, condutividade elétrica, cor, sólidos totais dissolvidos,dureza, oxigênio dissolvido, nitrogênio amoniacal, nitrato, nitrito, nitrogênio total, fosfato, fósforo total e clorofila-a. O rio Siriri Vivo apresenta uma boa qualidade da água ao contrário do rio Siriri Morto, que apresenta indicativo de estado eutrofização.

published_or_final_version / abstract / Geography / Master / Master of Philosophy

The growing demand for water in the arid regions of the West increases the need for optimal allocation of water among competing uses. An efficient allocation of water between instream and out-of-stream uses has been impeded by institutional constraints and the scarcity of information regarding instream flow benefits. The objectives of this thesis were to provide preliminary economic data on the value of instream water in "producing" recreational fishing and to examine the effect of forestry, agriculture, and livestock practices on temporal streamflow patterns and anadromous fish production. The steelhead trout (Salmo gairdneri) sport fishery within the John Day River basin in north-central Oregon provided the setting for this research. The interdisciplinary methodology employed in estimating the marginal value of water with respect to steelhead production consisted of two tasks. The first task involved valuing a marginal change in the quality of the steelhead recreational fishery. The contingent valuation method (CVM) was selected for this purpose. Both open- and closed-ended willingness-to-pay (WTP) questions were included in a questionnaire administered to John Day River steelhead anglers during the 1986/87 steelhead fishing season. Survey data were analyzed to arrive at individual and aggregate bid functions relating WTP to expected angling success rates. Results indicate that, under current conditions, the average angler is willing to pay approximately $7.20 to catch an additional steelhead. The second task of the instream water valuation methodology was directed at deriving a streamflow/steelhead production relationship. By including variables influencing steelhead production in a Ricker stock-recruitment model, it was possible to develop a model which could be estimated using linear regression techniques. Some difficulty arose, however, with interpretation of the model due to the unavailability of cohort escapement data and the subsequent use of standing crop data. While possibly masking the true magnitude of streamflow's effect on fish production, this drawback was not deemed limiting within the general context of the interdisciplinary methodology. Results of the biological model conformed to a priori expectations. Increases in summer and winter streamflows led to increased steelhead survival, whereas higher spring flows increased mortality levels. Other results indicate that the John Day Dam was responsible for a 31.5 percent decline in the population index for the 1969-1983 period. Combining the economic and biological results into one equation yielded an estimate of the marginal value of summer instream water in "producing" recreational steelhead angling. Similar equations were developed for winter and spring flows. The marginal value of water in producing recreational steelhead fishing within the John Day basin was estimated at $0.56 per acre-foot for summer flows, $0.046 for winter flows, and -$0.075 for spring flows. By including out-of-basin benefits, these values increased to $2.26, $0.19, and -$0.30, respectively. In comparison, water's value in irrigation within the John Day basin has been estimated at between $10 to $24 per acre-foot. However, nonuse values of steelhead, as well as the increased production of other fish species (such as spring chinook salmon) were not included in the instream water values. In addition, no attempt was made at valuing instream water's contribution to boating, camping, or other benefit-producing activities. A secondary objective of this thesis was to briefly examine the possible benefits accruing to other instream and out-of-stream users due to an alteration in streamflow patterns. In addition, the impact of activities by other resource users -- namely forestry, agriculture, and livestock production --on anadromous fish production was reviewed. Improper management practices by these activities can negatively impact the aquatic and riparian ecosystems. While no firm conclusions were drawn, it appears the quality of these ecosystems, as opposed to the amount of streamflow, has the largest marginal impact on anadromous fish populations. / Graduation date: 1988

A study was undertaken to determine the effect of urbanization on the rainfall-runoff relationship of a semiarid region. A concentrated network of rain gages was installed on the urban Tucson Arroyo-Arroyo Chico Watershed located in the city of Tucson, Arizona. Rainfall data from this watershed were compared with that of the non-urban Atterbury Experimental Watershed located to the southeast of the city of Tucson in order to determine if there were significant differences in the runoff from these two watersheds. In addition, test plots were constructed by the researcher for the study of the effects of intensity of precipitation, season, antecedent moisture, and percent of impervious cover on the rainfall-runoff relationship. Data from the test plots were compared with that of the Tucson Arroyo-Arroyo Chico Watershed. A prediction model was developed for the Tucson Arroyo-Arroyo Chico Watershed. The feasibility of retaining urban runoff for more beneficial uses was investigated. It was determined that the runoff from the urban Tucson Arroyo- Arroyo Chico Watershed was 4.75 times greater per square unit of area than that from the non-urban Atterbury Experimental Watershed. Significant factors in the rainfall-runoff relationships of the test plot data were found to be intensity of precipitation and amount of impervious cover. Season was found not to be significant. Antecedent moisture was a significant factor in the analysis of variance of the data. However, it was not significant in the regression analysis. In the comparison of the test plot data and the data from the Tucson Arroyo-Arroyo Chico Watershed, it was found that intensity of precipitation was the predominant factor in the rainfall-runoff relationship. In plotting the effects of intensity of precipitation versus runoff, the resulting graph indicated an increasing effect of impervious cover and intensity of precipitation on runoff from the test plots. A regression model was developed from the data of the Tucson Arroyo-Arroyo Chico Watershed. The factors of average precipitation and intensity of precipitation accounted for 82 percent of the variation in the analysis. Of these two factors, intensity of precipitation accounted for 68 percent of the variation. Duration of precipitation and the antecedent moisture index did not significantly increase the correlation coefficient of the regression analysis when they were included. The projected runoff from the city of Tucson would amount to less than 10 percent of the present yearly use. The treatment necessary for the domestic use of urban runoff would be greater than the present cost of producing municipal water from well-sites. Recharging this water into the groundwater supply appears to be the most feasible method of utilizing urban runoff at this time.

A continuous simulation streamflow model (i.e., SSARR - an acronym for Streamflow Synthesis and Reservoir Regulation) was evaluated and used to study winter streamflow from the Salt River Basin. This 4,306 square mile basin, which ranges in elevation from 2,200 to 11,500 feet, is associated with a diversity of watershed, vegetation, climatic and hydrologic characteristics. Program modifications allowed computation of potential evapotranspiration within the model. This provided improved flexibility in delineating simulation units and reduced the necessary time-dependent data inputs to daily values of precipitation and temperature. Refinement of initial parameter estimates and relationships was accomplished by trial and error methods. Four years of hydrometeorological data were utilized for model calibration and an additional four years used to test the validity of parameter estimates. Simulated hydrographs generally underestimated peak flows and overestimated recession flows following major rainfall events. The standard error of the estimate for simulated winter flows (November through May) was only 30,000 acre-feet for the calibration period but increased to approximately 120,000 acre-feet for the validation period. Average winter flows during the calibration and validation periods were 840,000 and 690,000 acre-feet, respectively. Approximately 25 to 45 percent of the winter runoff occurring after February 1, March 1 and April 1 could be predicted from simulated snowpack water equivalent and soil moisture conditions on the prediction date. High elevation portions of the basin were more efficient at producing streamflow from a given precipitation input than were the lower elevations. Maximum daily watershed efficiencies (ratio of generated runoff to rain and snowmelt inputs) usually occurred on the date of snowpack disappearance for the relatively high elevation simulation units. Simulated runoff volumes increased exponentially with increased basin precipitation but decreased linearly with increased basin air temperatures. For a selected winter period, simulations indicated streamflow response to a one-inch change in winter precipitation would be approximately 100,000 acre-feet, or 3.4 times greater than expected from a one-degree change in winter temperature.