Thesis (M.S.) University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 24, 2007) Vita. Includes bibliographical references.

Antibiotics are commonly used in animal agriculture to treat and prevent diseases and promote growth. Unfortunately, large amounts of antibiotics are not metabolized, but instead are excreted in urine and feces. Rainfall simulation studies were used to investigate the transport of the antibiotic oxytetracycline and various constituents in runoff and the ability of alum to reduce pollutant transport. Runoff samples were collected at several points during the simulated storm event from each of four treatments: control (C), manure only (M), manure and antibiotics (MA), and manure, antibiotics and alum (MAA). Flow-weighted composite samples were created and compared to the flow weighted mean concentration (FWMC). Constituents with concentrations well-above the detection limits (E. coli, NH4-N, turbidity, TSS, TOC, and EC) showed a strong correlation between flow-weighted composite samples and FWMC. When constituent concentrations were at or near the detection limits, errors associated with the composite samples were magnified. Oxytetracycline concentrations had the strong correlation to E. coli, Cl, TOC, TSS, and turbidity suggesting that a BMP effective at trapping sediment or particulates may work best for reducing oxytetracycline concentrations in runoff. Alum (1%) did not reduce levels of oxytetracycline in runoff. It is recommended that higher doses of alum be tested.

Highways and roadways are the major source of stormwater runoff due to their prevalence and large non-permeable surface area. Best Management Practices (BMPs) such as bioswale provide effective on-site management and control of stormwater runoff from linear infrastructure such as highways. Many factors affect the performance of bioswales for stormwater volume reduction. The ratio of the installed BMP area to its service drainage area, characteristics of precipitation and the amount of sediment build-up over the surface of the BMP area are among the most important factors. Earlier studies have indicated that volume reductions in stormwater runoff from bioswale application range from 50% to 94%. However, the reported research lacks adequate information for a full understanding of how bioswales perform under various conditions. Consequently, additional systematic and in-depth research to better understand and the potential of bioswales as a method of controlling stormwater runoff is indicated. This research examined the effect of the following factors on bioswale performance: the ratio of the BMP area to the service drainage area, precipitation amounts and intensity, and sediment build-up. Hydraulic and hydrological processes were developed and analyzed through conceptual and physical models using appropriate governing equations including the Green-Ampt method. Field study of discrete rainfall events was conducted to collect information to calibrate and validate the numerical models. The field study tested various bioswale conditions with different levels of sediment accumulation. It also considered expected soil loss in the study area using the Universal Soil Loss Equation (USLE) method. In addition to field study, extensive simulations were conducted considering various contributing areas, rainfall depth and intensity, and sediment accumulation. These variables were manipulated to evaluate their effect on runoff volume reduction. Findings indicate that, for a given rainfall depth and duration, increasing the ratio of the BMP area to the service drainage area from 4% to16% results in increased bioswale efficiency ranging from 84% to 99%. The results revealed that input flowrate to the bioswale ranged from 0.04 to 4.7 in./min. depending on the rainfall intensity and soil type in the area. The runoff reduction performance of a newly constructed bioswale ranged from 44% for the highest input flowrate to 99% for the lowest input flowrate rainfall events. On the low end of rainfall volume/intensity, a 4% increase in the BMP area ratio results in a 34% improvement in efficiency (50% to 84%). On the high end of rainfall volume/intensity, a 16% increase in the area ratio results in only a 5% increase in efficiency (94% to 99%). Results also show that sediment accumulation has a substantial negative effect on infiltration rate. The observed efficiency of a bioswale in runoff reduction ranged from 13% to 100%. According to the USLE, the expected amount of soil loss occurring in the right-of-way area of a highway is approximately 1 ton/acre annually. The research revealed that for a given rainfall depth, duration, and area ratio; increasing the amount of sediment accumulation from 0 lbs./sq. ft. (equivalent to a newly constructed bioswale) to 2.7 lbs./sq. ft. (equivalent to a 10-year old bioswale) results in a 52% reduction in the runoff effectiveness of the bioswale sub-catchment from 98% to 46%. Finally, the physical model and associated governing equations were analyzed to describe the process of each studied factor. These results can be used for further study where the sediment accumulation rates differ from those modeled in this research.

The work focuses how land use on the selected location affects the amount of phosphorus in the watershed Jenínský potok. Defines the basic concepts of this and related issues. The monitored values are total phosphorus and phosphorus contained in phosphate ions and description of the measuring apparatus. The resulting data are arranged in tables and graphs and resultes are compare with standards CSN and other similar studies.

The aim of this paper is to describe and compare various methods of runoff separation. Therefore it is necessary to explain basic hydrological terms that are important for understanding the water regime of landscape. Long-term monitoring of the water regime of the whole catchment area can provide successful detection of hydrological extremes such as droughts or devastating floods. The paper is divided in two parts. The theoretical part includes the literature rerview explaining basic hydrological terms and individual components of water cycle in nature, summary of methods usually used for runoff separation, and the description of the applied methods. The practical part specifies the locality of Jenínský stream, located in the Český Krumlov district. This part further reflects separation of runoff based on the daily runoffs. Methods GROUND, MPGM and Chapman digital filter have been chosen to compare primary runoff and direct runoff. We have also considered the method of separation of minimal monthly runoff according to Kille for seven-year period in relation to the methods mentioned above. Finally, we have chosen several discharge waves for the method of recession curve analysis. The paper compares direct and primary runoff separated by individual methods in the catchment area of our interest.

Thesis (Master Diploma (Civil engineering)--Cape Technikon, Cape Town,1993 / Stormwater pollution is a major problem in many of the areas where it is present. Due to the changing nature in terms of quality and quantity of stormwater, which has its origin in many different places, it is difficult to control and identify the source of pollution. Some of the pollutants present in stormwater run-off include oxygen-demanding substances, suspended solids, trace metals, toxic organic compounds (eg. chlorinated hydrocarbons), nutrients, refuse, plastics and pathogenic bacteria and viruses. This thesis identifies and discusses the problems in the Lourensriver catchment area, and produce practical solutions to decrease the pollution. The report consists of four sections. Part I : Part 2 : Part 3 : Part 4 : Evaluation of the existing area and identification of the problem. Literamre study. Control of Stormwater ie. storing, treatment and disposal. Presencation of steps to be followed to rectify the problem. If the findings and recommendations are followed, it should make a positive contribution to the wellbeing of the catchment area. The findings of this report could also be applied to areas with similar problems. The following recommendations are made for the Lourens River: " Monitor and strict implementation of the Wateract (1936). " In the Lower zone, pollution can be diluted and flushed out by ways of the closure of Melkschloot. " Design of any new development must take place in such a manner so as the stormwater discharge after development will be of the same quality and quantity as before construction. " Creation of permeable surfaces in established areas. " Delay of rainwater flow out of all areas. " Construction of additional sedimentation and detention dams for the storing and treatment of stormWater. " Awareness programmes to inform the public and industry. " Implementation of preventative measurements. " Establishment of controlling body's to ensure co-ordination betvieen various institutions and local government. " Monitor of run-off from industrial and agricultural terrain and identifying of unlawful practices. Strict anti-littering and dumping actions. Placing of waste storage bins in residential and industrial areas. Permits for the usage of poisons and the monitor there off. Encouragement of cleaning up actions and groups. Encouragement and increase of street cleaning operations. Construction of effective catchment basins to remove sol ids before it ends up in the stormwater pipes. Regular cleaning of catchment basins. Regular flushing of stormwater pipes. Construction of marshlands. Construction of reedbeds.

abstract: Understanding agricultural land use requires the integration of natural factors, such as climate and nutrients, as well as human factors, such as agricultural intensification. Employing an agroecological framework, I use the Perry Mesa landscape, located in central Arizona, as a case study to explore the intersection of these factors to investigate prehistoric agriculture from A.D. 1275-1450. Ancient Perry Mesa farmers used a runoff agricultural strategy and constructed extensive alignments, or terraces, on gentle hillslopes to slow and capture nutrient rich surface runoff generated from intense rainfall. I investigate how the construction of agricultural terraces altered key parameters (water and nutrients) necessary for successful agriculture in this arid region. Building upon past work focused on agricultural terraces in general, I gathered empirical data pertaining to nutrient renewal and water retention from one ancient runoff field. I developed a long-term model of maize growth and soil nutrient dynamics parameterized using nutrient analyses of runoff collected from the sample prehistoric field. This model resulted in an estimate of ideal field use and fallow periods for maintaining long-term soil fertility under different climatic regimes. The results of the model were integrated with estimates of prehistoric population distribution and geographical characterizations of the arable lands to evaluate the places and periods when sufficient arable land was available for the type of cropping and fallowing systems suggested by the model (given the known climatic trends and land use requirements). Results indicate that not only do dry climatic periods put stress on crops due to reduced precipitation but that a reduction in expected runoff events results in a reduction in the amount of nutrient renewal due to fewer runoff events. This reduction lengthens estimated fallow cycles, and probably would have increased the amount of land necessary to maintain sustainable agricultural production. While the overall Perry Mesa area was not limited in terms of arable land, this analysis demonstrates the likely presence of arable land pressures in the immediate vicinity of some communities. Anthropological understandings of agricultural land use combined with ecological tools for investigating nutrient dynamics provides a comprehensive understanding of ancient land use in arid regions. / Dissertation/Thesis / Ph.D. Anthropology 2013

abstract: Climate and its influence on hydrology and weathering is a key driver of surface processes on Earth. Despite its clear importance to hazard generation, fluvial sediment transport and erosion, the drawdown of atmospheric CO₂ via the rock cycle, and feedbacks between climate and tectonics, quantifying climatic controls on long-term erosion rates has proven to be one of the grand problems in geomorphology. In fact, recent attempts addressing this problem using cosmogenic radionuclide (CRN) derived erosion rates suggest very weak climatic controls on millennial-scale erosion rates contrary to expectations. In this work, two challenges are addressed that may be impeding progress on this problem. The first challenge is choosing appropriate climate metrics that are closely tied to erosional processes. For example, in fluvial landscapes, most runoff events do little to no geomorphic work due to erosion thresholds, and event-scale variability dictates how frequently these thresholds are exceeded. By analyzing dense hydroclimatic datasets in the contiguous U.S. and Puerto Rico, we show that event-scale runoff variability is only loosely related to event-scale rainfall variability. Instead, aridity and fractional evapotranspiration (ET) losses are much better predictors of runoff variability. Importantly, simple hillslope-scale soil water balance models capture major aspects of the observed relation between runoff variability and fractional ET losses. Together, these results point to the role of vegetation water use as a potential key to relating mean hydrologic partitioning with runoff variability. The second challenge is that long-term erosion rates are expected to balance rock uplift rates as landscapes approach topographic steady state, regardless of hydroclimatic setting. This is illustrated with new data along the Main Gulf Escarpment, Baja, Mexico. Under this conceptual framework, climate is not expected to set the erosion rate, but rather the erosional efficiency of the system, or the steady-state relief required for erosion to keep up with tectonically driven uplift rates. To assess differences in erosional efficiency across landscapes experiencing different climatic regimes, we contrast new CRN data from tectonically active landscapes in Baja, Mexico and southern California (arid) with northern Honduras (very humid) alongside other published global data from similar hydroclimatic settings. This analysis shows how climate does, in fact, set functional relationships between topographic metrics like channel steepness and long-term erosion rates. However, we also show that relatively small differences in rock erodibility and incision thresholds can easily overprint hydroclimatic controls on erosional efficiency motivating the need for more field based constraints on these important variables. / Dissertation/Thesis / Doctoral Dissertation Geological Sciences 2014

Submitted by (edna.saturno@ufrpe.br) on 2016-06-28T15:42:11Z No. of bitstreams: 1 Luciana Maranhao Pessoa.pdf: 566902 bytes, checksum: 50b56fbd70d205293b9dce6101138933 (MD5) / Made available in DSpace on 2016-06-28T15:42:11Z (GMT). No. of bitstreams: 1 Luciana Maranhao Pessoa.pdf: 566902 bytes, checksum: 50b56fbd70d205293b9dce6101138933 (MD5) Previous issue date: 2007-02-19 / This study aimed to contribute to the understanding of the seed bank seasonal and spatial variation in two different topographic situations (upper and lower slopes), two types of erosion (rills and interrills) and two periods (dry and rainy seasons) in an area of caatinga located in Serra Talhada municipality, state of Pernambuco (PE). Sixty soil samples were collected and 60 erosion pins were installed near each soil collection spot, in the intention of evaluating the removal level and deposition of the soil, in the two climatic seasons and in the rills and interrills. The bank’s density was evaluated by the emerged plantules method. About 79% of the seeds germinated in the bank are herbaceous annual. The density of germinated viable seeds was greater during the rainy (5.727,3 seeds/m2) that in the dry season (1.369,0 seeds/m2), and the upper than in the lower slope in both period. With relationship to the erosion types, there was just at that significant difference rainy season, where the interrills presented greater number of seeds and larger removal of the soil. The seasonal variation of the bank is registered in other arid andsemi-arid areas of the world that also point prevalence of herbaceous of short life cycle and larger density in the rainy period. Possible explanations for these patterns point the need of more studies on caatinga erosion, once the results of the removal-deposition processes differed of the told in the literature. / Este trabalho objetivou compreender a variação sazonal e espacial do banco de sementes da caatinga em duas situações topográficas (encosta superior e inferior) e tipos de erosão (sulcos e entressulcos) em épocas seca e chuvosa. Foram realizadas 60 coletas de amostras de solo e instalados 60 vergalhões de ferro, próximos ao local de cada coleta do solo, no intuito de avaliar o nível de remoção e deposição do solo, nas duas estações climáticas e nos sulcos e entressulcos. A densidade do banco foi avaliada do método de emergência de plântulas. Cerca de 79% das sementes germinadas no banco são herbáceas anuais. A densidade de sementes viáveis germinadas foi maior na época de chuva (5.727,3 sementes/m2) que na época de seca (1.369,0 sementes/m2). A encosta superior apresentou maior número de indivíduos em ambas as épocas. Com relação aos tipos de erosão, houve apenas diferença significativa na época chuvosa, onde os entressulcos apresentaram maior número de sementes e maior remoção do solo. A variação sazonal do banco é registrada em outras áreas áridas e semi-áridas do mundo que também apontam predomínio de herbáceas de ciclo de vida curto e maior densidade no período chuvoso. Possíveis explicações para estes padrões apontam a necessidade de mais estudos sobre erosão de caatinga, uma vez que os resultados dos processos de remoção-deposição diferiram do relatado na literatura.

Orientador: Abel Maia Genovez / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-16T10:31:50Z (GMT). No. of bitstreams: 1 Sartori_Aderson_D.pdf: 3397491 bytes, checksum: 8147da562efaa3f3c0aecd4fa9efb4b9 (MD5) Previous issue date: 2010 / Resumo: O Método do CN ("Runoff Curve Number Method") é usado mundialmente para estimar a chuva excedente. As maiores dificuldades de aplicação do método fora do país de origem estão relacionadas com a definição dos grupos hidrológicos de solo e a falta de valores locais de referência para o parâmetro CN. As características gerais dos grupos hidrológicos de solos, inicialmente propostas para os EUA (SCS, 1972), são ainda muito usadas no Brasil. Por serem baseadas principalmente na textura dos solos elas não fornecem critérios objetivos para sua aplicação, pois a textura não é suficiente para classificar um solo hidrologicamente. A classificação hidrológica de solos revisada do "Natural Resources Conservation Service - NRCS" possui critérios claros e objetivos, mas para serem aplicados necessitam de medições de condutividade hidráulica saturada ao longo do perfil de solo. Estes dados são escassos no Brasil. Assim, neste trabalho foi proposta uma classificação hidrológica de solos alternativa para minimizar a dificuldade de classificar um solo hidrologicamente sem ter dados de condutividade hidráulica saturada. Esta classificação é baseada em propriedades de solos disponíveis nos boletins de levantamento e na classificação dos solos, as quais podem ser usadas como substitutas a condutividade hidráulica saturada. Também foram avaliados seis métodos de calibração do CN ("National Engineering Handbook"; Mínimos Quadrados; Curva de Freqüência; P/S > 0,46: Assintótico; Freqüência Log-normal) e valores de referência foram determinados. Usando 58 perfis de solo com medições de condutividade hidráulica saturada ao longo do perfil, a classificação hidrológica proposta foi comparada com a do NRCS (2007). Os resultados obtidos mostraram boa correspondência entre elas, indicando que a classificação proposta é adequada à realidade do Brasil. Com dados observados de chuva e escoamento superficial direto em 15 bacias hidrográficas foi realizada uma análise comparativa dos métodos de calibração do CN, que mostrou serem os métodos Assintótico e Mínimos Quadrados mais adequados para calibrar o CN usando séries totais e parciais. Portanto, estes métodos foram adotados para determinar o CN de referência para os usos: solo nu, solo sem cultivo, milho, soja e trigo em rotação, cana-de-açúcar, eucalipto, cactos e caatinga. / Abstract: The Runoff Curve Number Method is used worldwide to estimate the rainfall excess, especially for ungauged watersheds. The major difficulties of applying the method outside the USA are related to hydrologic soil groups' definition and lack of local reference values for the CN parameter. The general characteristics of the hydrological soil groups initially proposed to the USA (SCS, 1972), which are based mainly on soil texture, are still widely used in Brazil. These general features do not provide objective criteria for its application within and outside the USA because the texture is not sufficient to assign soils to hydrologic soil groups. The NRCS revised soil hydrological classification (NRCS, 2007) has clear and objectives criteria, but measurements of saturated hydraulic conductivity along the soil profile for its use are needed. These data are scarce in Brazil, which makes difficult its direct application. Thus, in this work it is proposed an alternative soil hydrological classification to minimize the difficulty of classifying a soil without having saturated hydraulic conductivity data. This classification is based on available soil properties in the Brazilian soil survey bulletins and classification, which can work as surrogate of soil hydraulic properties. It is also evaluated six methods of CN calibration (National Engineering Handbook; Least Squares; Frequency Curve; P/S > 0.46; Asymptotic; Frequency Log-normal) and reference values were determined. The proposed hydrologic classification was compared with the NRCS hydrologic classification (NRCS, 2007) using 58 soil profiles with measurements of hydraulic conductivity along the profile. The results showed good correspondence between them. This indicates that the proposed hydrologic classification is appropriate for the reality of Brazil. With measured rainfall and runoff data from 15 watersheds was conducted an analysis to compare the six methods of CN calibration. This analysis showed that the Asymptotic and Least Squares methods were the most suitable for the CN calibration using total and partial series. Therefore, these two methods were used to determine the reference CN for the following land uses: bare soil, fallow soil, corn, soybeans and wheat in rotation, sugar cane, eucalyptus, cactus and caatinga. / Doutorado / Recursos Hidricos / Doutor em Engenharia Civil