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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

Estudo do comportamento de um escorregamento ativo na Serra da Cantareira - SP. / Study the landslide active behavior in the Serra da Cantareira - SP.

Godois, João Vítor da Silva 16 September 2011 (has links)
Esta dissertação apresenta o estudo sobre um caso de movimento rotacional em uma massa de solo coluvionar, localizada na Vila Albertina na zona norte da cidade de São Paulo-SP. O objetivo deste trabalho foi estudar os processos de instabilidade associados a eventos de chuvas, condições de fluxo e ações antrópicas que ocorreram no local. Procurou-se estabelecer as relações de causa e efeito que os eventos pluviométricos têm sobre a estabilidade da encosta; também foram estudadas as alterações causadas pelo homem e as condições de infiltração de água no terreno. Foi realizado um levantamento histórico de escorregamentos ocorridos na região desde a década de 30. Este levantamento histórico constituiu em resgatar aerofotografias, imagens de satélites e reconstituições de plantas topográficas do local. Através deste estudo se constatou que a encosta começou a ser modificada desde a década de 40, com uma possível tentativa de exploração de rochas graníticas. Nos anos 60 foi construída uma fábrica no pé da encosta. Atualmente, o solo desta encosta, que está em movimento, invade o pátio desta fábrica. Na década de 70, a área de escorregamento começou a ser ocupada por moradores, que construíram suas casas sobre esta encosta. Esta ocupação foi desordenada e acelerou o processo de instabilização da encosta; até o ano de 2004 viviam no local 600 famílias. No início da década de 80, a encosta apresentou grandes movimentações. Para que estes movimentos fossem cessados, realizaram-se obras de contenção, foram executados retaludamentos, instalações de drenos profundos e drenagens superficiais através de canaletas e escadas hidráulicas. Ainda na década de 80, retirou-se uma grande camada de solo da encosta para cobrir o aterro sanitário da Vila Albertina, localizado no terreno vizinho a encosta. Esta remoção deixou parte do terreno plano, causado o acumulo de águas pluviais. As águas, que antes escoariam superficialmente, passaram a se infiltrar no terreno. Para a caracterização e obtenção dos parâmetros de resistência dos solos da região, foram coletadas três amostras indeformadas: uma na crista do escorregamento e duas no pé da encosta. Neste local, foram identificados um solo coluvionar e um solo residual mais jovem. A encosta foi instrumentada através de marcos superficiais, inclinômetros que também serviram de medidores de nível d\'água e tensiômetros. / This paper presents a study on a rotational movement in a colluvial soil mass located at Vila Albertina, northern region of São Paulo City. The main purpose of this work is to study the processes of instability related to rainfalls, conditions of flow and human actions that occurred at the site. It was intended to establish cause and effect relations pluviometric events have over the stability of the slope. It also studies alterations caused by men and water infiltration conditions on the land. A historical survey of ground sliding data on the region since the 1930s was gathered. This survey was composed of retrieved material such as aerial photographs, satellite images and topographic plans reconstitutions of the location. By means of this study, it was possible to verify that the slope started to be modified since the1940s, with a possible attempt of granite rocks exploitation. In the 60s, a factory was built on the bottom of the slope. Nowadays, the soil of this slope, which is in movement, is invading the courtyard of this factory. In the 70s, the sliding area started to be occupied by inhabitants, who built their homes on this slope. This disorderly occupancy accelerated the instability of the slope; until 2004, 600 families were living in the location. In the beginning of the 80s, the slope presented considerable movements. In order to stop them, contention constructions were executed, as well as re-sloping, installation of deep drains and superficial drainage by channels and hydraulic stairs. Still in the 80s, a great layer of the slopes soil was taken to cover Vila Albertinas sanitary landfill, located at land nearby. This removal left part of the ground plain, causing an accumulation of pluvial water. The pluvial water, which would superficially drain, started to infiltrate into the ground. To characterize and acquire the regions soil resistance parameters, three undisturbed samples were collected: one at the top of the sliding and two at the bottom of the slope. In this area, colluvial and a more recent residual soil were identified. The slope was monitored by superficial indicators, tensiometers and inclinometers that were also used to measure the water level.
212

The Effect of the Slope of the Psychometric Function on the Measurement of Speech Recognition Threshold Using a Male Talker

Bakhsh, Nujod Ali 01 June 2018 (has links)
Speech audiometry is the aspect of audiology that provides critical information on how individuals hear one of the most important sounds of daily life: speech. The speech recognition threshold (SRT) is a measure of speech audiometry that is widely used to provide information on an individual's capacity to hear speech. Over time, researchers and clinicians have worked to improve the SRT by developing and modifying a variety of word lists to be used during testing. Eventually, spondaic words were selected as the best stimuli for the SRT. The spondaic words had to meet four criteria: familiarity, phonetic dissimilarity, normal sampling of English sounds, and homogeneity with respect to audibility. This study examined the aspect of homogeneity with regard to slope of the psychometric function. Specifically, whether slope of the psychometric function had an effect on the number of words used to obtain the SRT, and thus reduce test time, as well as whether slope had an effect on the relationship between the SRT and the pure-tone average (PTA). It was hypothesized that words with a steep slope would significantly reduce test time and yield a close SRT-PTA agreement. Three word lists (steep, medium, and shallow sloping words), all recorded by a male talker, were used to obtain the SRT on 40 participants (ages 18-30 years). Statistical analysis showed significant differences in the number of words to obtain the SRT and the SRT-PTA agreement. However, when the differences were examined from a clinical perspective, the results were negligible. When compared with words with medium and steep slopes, words with shallow slope required an average of four extra words to obtain the SRT, which does not result in a meaningful reduction in test time. For clinical purposes, it appears that the slope of the psychometric function does not need to be taken into consideration for the SRT. Clinicians may use a variety of words as long as they meet the original four criteria for selection of spondees.
213

The Effect of the Slope of the Psychometric Function on the Measurement of Speech Recognition Threshold Using a Female Talker

Reese, Jessica Lee 01 June 2018 (has links)
Speech audiometry has long been a component of a thorough audiological examination. The speech recognition threshold (SRT) measurement is perhaps the most widely used measurement in speech audiometry. For decades, researchers and clinicians have worked to create and fine-tune word lists that for use in SRT testing; their aim being to improve the accuracy for classifying a client's ability to hear and comprehend speech. Experts in the field have agreed to follow four tenets of speech audiometry when selecting word sets. This study examined whether improvement to stimulus lists for SRT measurement could be made in regards to the tenet of homogeneity with respect to audibility if the slope of the psychometric function were a selection consideration. The study was performed with the hypothesis that steeply sloping words would significantly reduce the number of words needed to obtain the SRT. Three word lists, all recorded by a female talker, comprising of steeply sloping words, medium sloping words, and shallow sloping words, were used in the study. Participants with normal hearing between the ages of 18 and 30 years provided data that was used to calculate SRT measurements for all three lists from each ear. The results showed a significant difference in the number of words needed to obtain the SRT when comparing the steep and shallow word sets and the shallow and medium word sets. Steeply sloping words required fewer words to obtain the SRT, M = 17.02. Shallow sloping words required the most words, M = 18.88, amounting to a difference of 1.86 words. While statistically different, a reduction by fewer than 2 words during the course of SRT testing will not equate to a substantial saving of time for the clinician. For clinical application, the slope of the psychometric function of the words used in SRT measurement need not be a primary consideration when developing stimulus lists.
214

Air Vent Sizing in Low-Level Outlet Works for Small- to Medium-Sized Dams

Wright, Nathan W. 01 May 2013 (has links)
The majority of dams contain low-level outlet works, which typically consist of closed conduits that run through the dam, and are used to release water from the reservoir when the water level is below the level of the surface spillways. It is also used to flush the reservoir of sediments and to control the elevation of the reservoir. Low-level outlet works typically consist of a gate that controls the flow within a closed conduit that runs through the dam and an air vent that supplies air behind the gate. In the absence of properly designed air vents, negative pressures may develop downstream of the gate. These negative pressures could potentially lead to cavitation and vibration damage. Properly sized air vents help maintain the downstream air pressure at or near atmospheric pressure and/or provide air to absorb the energy generated by cavitation, reducing the potential for damage. The majority of research done on air vent sizing is for dams having large dam geometry, which consist of a pressurized conduit leading to a vertical slide gate that is followed by a discharge tunnel. The typical air vent design for these large dams uses the water flow rate and the Froude number measured at the vena contracta downstream of the gate. The low-level outlet works for small-to-medium-sized embankment dam geometries typically have an inclined slide gate, installed at the inlet on the upstream face of the dam slope, followed by an elbow that connects to a conduit that passes through the dam and discharges downstream. This type of outlet geometry does not produce the typical vena contracta. Consequently, the use of the Froude number, at the vena contracta , as a characteristic parameter for characterizing airflow demand is not practical. Recently a laboratory study was performed calculating the head-discharge characteristics of low-level outlets for small-to-medium sized dam geometries. In addition to validating some of the previous laboratory-scale air venting research, the objective of this study was field verification of air-demand/air vent sizing predicted by the laboratory-based method. The influence of conduit slope, air port location, and hydraulic jumps on air demand was also evaluated in the laboratory. The findings of this study can be found within this thesis.
215

Browse Evaluation and Survey Techniques for the Uinta North Slope Moose Herd

Babcock, William H. 01 May 1977 (has links)
A study was conducted on the North Slope of the Uinta Mountains from January, 1972 through June, 1974, to determine the effects of three simulated levels of moose utilization on the crude protein content, phosphorus content, digestibility and vigor of willow plants. A comparison was also made on the crude protein content, phosphorus content and digestibility of current year's versus past years' willow growth. Finally, the validity of direct and indirect population enumeration methods was compared for the possible development of a standardized moose survey technique. Clipping caused a highly significant increase in crude protein and phosphorus content between treatment levels. There was also a highly significant increase in digestibility between years. Plant vigor comparisons were confounded by additional sources of mortality and the effects of environmental variables. A comparison of the nutrient content and digestibility of 1 t o 5 year-old willow growth showed that crude protein content, phosphor us content and digestibility decreased with increasing twig age. Additional factors are discussed which indicate that the carrying capacity of the winter range is larger than previously described. A poor correlation was found be tween direct aerial moose observations and indirect population estimates from pellet-group counts.
216

Alpine lake sediment archives and catchment geomorphology : causal relationships and implications for paleoenvironmental reconstructions

Rubensdotter, Lena January 2006 (has links)
<p>Lake sediments are frequently used as archives of climate and environmental change. Minerogenic sediment variability in alpine lakes is often used to reconstruct past glacier and slope process activity. Alpine lake sediments can however have many different origins, which may induce errors in paleoenvironmental reconstructions. The aim of this project was to enhance the understanding of minerogenic lake sedimentation in alpine lakes and improve their use as environmental archives.</p><p>Catchment geomorphology and Holocene sediment sequences were analysed for five alpine lakes. Several minerogenic sediment sources were detected in catchments and sediment sequences. Slope-, fluvial-, periglacial-, nival- and aeolian sediment transportation processes contribute to create complex lake sediment patterns. Large variations in sedimentation rates were discovered within and between lakes, which has implications for sampling strategies and age-model constructions. Similar fine-grained minerogenic laminations were found in four of the investigated lakes, despite large differences in setting. The demonstrated similarity between glacial and non-glacial lakes may complicate interpretations of glaciolacustrine sediment signals.</p><p>The main conclusion is that lake sedimentation in alpine environments is highly dependent on several geomorphological factors. All lakes should therefore be viewed as unique and the geomorphology should be thoroughly investigated before environmental reconstructions are based on lake sediment proxies. This study has confirmed the multi-source origin of alpine lake sediment, which also opens possibilities of more multi-faceted paleoenvironmental studies. Different process-proxies could potentially be used to separate different climate signals, e.g. precipitation, temperature and wind, in lake sediments. Analysis of grain-size distribution, detailed mineralogy and magnetic mineralogy in combination with X-ray radiography are suggested methods for such reconstructions.</p>
217

Road Slope Estimation

Larsson, Martin January 2010 (has links)
<p>Knowledge about the current road slope can improve several applications in a heavy-duty vehicle such as predictive cruise control and automated gearbox control. In this thesis the possibility of estimating the road slope based on signals from a vehicles air suspension system has been studied. More specifically, the measurement consists of a pressure signal measuring the axle load, and a vertical distance sensor.</p><p>A variety of suspension systems can be mounted on a Scania truck. During this thesis, two discrete-time models based on two different rear axle air suspension systems have been proposed. The models use the effect of alternating axle load during a change in the road slope and the estimates are computed using an extended Kalman filter.</p><p>The first model is based on a rear axle suspension known as the 2-bellow system. This type of suspension is strongly affected by the driveshaft torque, which results in a behaviour where the rear end is pushed upwards and thus decreasing the rear axle load during uphill driving. A model was developed in order to compensate for this behaviour. Unfortunately, the estimates showed less promising results and all attempts to determine the error was unsuccessful.</p><p>The latter model is based on the 4-bellow system. This suspension system is not affected by the driveshaft torque and a less complex model could be derived. The experimental results indicated that road slope estimation was possible and with a fairly accurate result. However, more work is needed since the estimate is affected by road surface irregularities and since the algorithm requires knowledge about the vehicles mass and the location of the centre of gravity.</p><p>All the presented results have been estimated based on real data from a test track at Scania Technical Centre in Södertälje.</p>
218

Height and Gradient from Shading

Horn, Berthold K.P. 01 May 1989 (has links)
The method described here for recovering the shape of a surface from a shaded image can deal with complex, wrinkled surfaces. Integrability can be enforced easily because both surface height and gradient are represented. The robustness of the method stems in part from linearization of the reflectance map about the current estimate of the surface orientation at each picture cell. The new scheme can find an exact solution of a given shape-from-shading problem even though a regularizing term is included. This is a reflection of the fact that shape-from-shading problems are not ill-posed when boundary conditions are available or when the image contains singular points.
219

Evaluation of the application uniformity of subsurface drip distribution systems

Weynand, Vance Leo 30 September 2004 (has links)
The goal of this research was to evaluate the application uniformity of subsurface drip distribution systems and the recovery of emitter flow rates. Emission volume in the field, and laboratory measured flow rates were determined for emitters from three locations. Additionally, the effects of lateral orientation with respect to slope on emitter plugging was evaluated. Two different emitters were tested to evaluate slope effects on emitter plugging (type Y and Z). The emitters were alternately spliced together and installed in an up and down orientation on slopes of 0, 1, 2 and 4% and along the contour on slopes of 1 and 2%. The emitters were covered with soil and underwent a simulated year of dosing cycles, and then flushed with a flushing velocity of 0.6 m/s. Initial flow rates for the two emitter types were 2.38 L/hr with a C.V. of 0.07. There was no significant difference in flow rates among slopes for type Y emitters, but there was a significant difference between the 1% and 2 % contour slopes for type Z emitters. Application uniformity of three different laterals at each site was evaluated. Sections of the lateral from the beginning, middle and end were excavated and emission volumes were recorded for each emitter. Application uniformity of laterals ranged from 48.69 to 9.49%, 83.55 to 72.60%, and 44.41 to 0% for sites A, B, and C, respectively. Mean emitter flow rate was 2.21, 2.24, and 2.56 L/hr for sites A, B, and C, respectively under laboratory conditions. Application uniformity under laboratory conditions ranged from 70.97 to 14.91%, 86.67 to 79.99%, and 85.04 to 0.00% for sites A, B, and C, respectively. A flushing velocity of 0.15 m/s with no chlorination, shock chlorination of 3400 mg/L and flushing velocity of 0.15 m/s, and shock chlorination of 3400 mg/L and flushing velocity of 0.6 m/s treatment regiments were applied to all laterals collected to assess emitter flow rate recovery to the nominal flow rate published by the manufacturer. All laterals showed an increase in the number of emitters within 10% of the published nominal flow rate.
220

Quantifizierung von Oberflächenabfluss und Erosion auf Böden mit hydrophoben Eigenschaften / Quantification of surface runoff and soil erosion on water repellent soils

Kuhnert, Matthias January 2009 (has links)
Die Zielsetzung der vorliegenden Arbeit ist die Beschreibung hydrophober Bodeneigenschaften und deren Auswirkungen auf Oberflächenabfluss und Erosion auf verschiedenen Skalen. Die dazu durchgeführten Untersuchungen fanden auf einer Rekultivierungsfläche im Braunkohlegebiet Welzow Süd (Südostdeutschland) statt. Die Prozesse wurden auf drei Skalen untersucht, die von der Plotskala (1m²) über die Hangskala (300m²) bis zur Betrachtung eines kleinen Einzugsgebietes (4ha) reichen. Der Grad der hydrophoben Bodeneigenschaften wurde sowohl direkt, über die Bestimmung des Kontaktwinkel, als auch indirekt, über die Bestimmung der Persistenz, ermittelt. Dabei zeigte sich, dass der Boden im Winterhalbjahr hydrophil reagierte, während er im Sommerhalbjahr hydrophobe Bodeneigenschaften aufwies. Die Ergebnisse deuten darauf hin, dass ansteigende Bodenwassergehalte, die in der Literatur häufig als Ursache für einen Wechsel der Bodeneigenschaften angegeben werden, auf dieser Fläche nicht zu einem Umbruch der Bodenbedingungen führen. Stattdessen kam es als Folge des Auftauens von gefrorenem Boden zu hydrophilen Bodeneigenschaften, die zu einem Anstieg des Bodenwassergehalts führten. Räumliche Unterschiede zeigten sich in den geomorphologischen Einheiten. Rinnen und Rillen wiesen seltener hydrophobe Eigenschaften als die Zwischenrillenbereiche und Kuppen auf. Diese räumlichen und zeitlichen Variabilitäten wirkten sich auch auf den Oberflächenabfluss aus, der als Abflussbeiwert (ABW: Quotient aus Abfluss und Niederschlag) untersucht wurde. Der ABW liegt auf Böden mit hydrophoben Bodeneigenschaften (ABW=0,8) deutlich höher als bei jenen mit hydrophilen Eigenschaften(ABW=0,2), wie sie im Winter oder auf anderem Substrat vorzufinden sind (diese Werte beziehen sich auf die Plotskala). Betrachtet man die Auswirkungen auf unterschiedlichen Skalen, nimmt der Abflussbeiwert mit zunehmender Flächengröße ab (ABW = 0,8 auf der Plotskala, ABW = 0,5 auf der Hangskala und ABW = 0,2 im gesamten Gebiet), was in den hydrophil reagierenden Rillen und Rinnen auf der Hangskala und dem hydrophilen Substrat im Einzugsgebiet begründet ist. Zur Messung der Erosion wurden verschiedene, zum Teil neu entwickelte Methoden eingesetzt, um eine hohe zeitliche und räumliche Auflösung zu erreichen. Bei einer neu entwickelten Methode wird der Sedimentaustrag ereignisbezogen über eine Waage bestimmt. In Kombination mit einer Kippwaage ermöglicht sie die gleichzeitige Messung des Oberflächenabflusses. Die Messapparatur wurde für Gebiete entwickelt, die eine überwiegend grobsandige Textur aufweisen und nur geringe Mengen Ton und Schluff enthalten. Zusätzlich wurden zwei Lasersysteme zur Messung der räumlichen Verteilung der Erosion eingesetzt. Für die erste Methode wurde ein punktuell messender Laser in einer fest installierten Apparatur über die Fläche bewegt und punktuell Höhenunterschiede in einem festen Raster bestimmt. Durch Interpolation konnten Bereiche mit Sedimentabtrag von Akkumulationsbereiche unterschieden werden. Mit dieser Methode können auch größere Flächen vermessen werden (hier 16 m²), allerdings weisen die Messungen in den Übergangsbereichen von Rinne zu Zwischenrille große Fehler auf. Bei der zweiten Methode wird mit einer Messung ein Quadratmeter mit einer hohen räumlichen Auflösung komplett erfasst. Um ein dreidimensionales Bild zu erstellen, müssen insgesamt vier Aufnahmen von jeweils unterschiedlichen Seiten aufgenommen werden. So lassen sich Abtrag und Akkumulation sehr genau bestimmen, allerdings ist die Messung relativ aufwendig und erfasst nur eine kleine Fläche. Zusätzlich wurde der Sedimentaustrag noch auf der Plotskala erfasst. Die Messungen zeigen, korrespondierend zu den Bodeneigenschaften, große Sedimentausträge während des Sommerhalbjahrs und kaum Austräge im Winter. Weiterhin belegen die Ergebnisse eine größere Bedeutung der Rillenerosion gegenüber der Zwischenrillenerosion für Niederschlagsereignisse hoher Intensität (>25 mm/h in einem zehnminütigem Intervall). Im Gegensatz dazu dominierte die Zwischenrillenerosion bei Ereignissen geringerer Intensität (<20 mm/h in einem zehnminütigem Intervall), wobei mindestens 9 mm Niederschlag in einer Intensität von mindesten 3,6 mm/h nötig sind, damit es zur Erosion kommt. Basierend auf den gemessenen Abflüssen und Sedimentausträgen wurden Regressiongleichungen abgeleitet, die eine Berechnung dieser beiden Prozesse für die untersuchte Fläche ermöglichen. Während die Menge an Oberflächenabfluss einen starken Zusammenhang zu der Menge an gefallenem Niederschlag zeigt (r² = 0,9), ist die Berechnung des ausgetragenen Sedimentes eher ungenau (r² = 0,7). Zusammenfassend beschreibt die Arbeit Einflüsse hydrophober Bodeneigenschaften auf verschiedenen Skalen und arbeitet die Auswirkungen, die vor allem auf der kleinen Skala von großer Bedeutung sind, heraus. / The objective of the thesis is the investigation of water repellent soil conditions and their consequences on surface runoff and erosion by water on different scales. The test site is a lignite mining area situated in Welzow Süd (south east Germany). The processes are to investigate on three different scales, starting with a plot scale (1 m²), then a hill slope scale (300 m²) and, finally, with a small catchment area (4 ha). The level of water repellency was quantified by both direct (contact angle) and indirect measurement (persistence of the soil). The results show seasonal differences with hydrophilic soil conditions during winter and water repellent reactions during summer. For this change in soil conditions, the soil water content is pronounced in literature to be the most important factor. On the test site, the soil water content changed instead as a consequence of the thawing of the soil which affects the hydrophilic conditions of the soil itself. The spatial differences of the soil water content are related to rill and channel areas (hydrophillic) and to knoll areas (water repellent). Both the spatial as well as the temporal variation of the soil conditions affect surface runoff which is investigated as a runoff coefficient (RC: ratio of amount of surface runoff to amount of precipitation). The RC shows higher values on soil with water repellent conditions (RC=0.8) in comparison with the values on hydrophilic soils (RC=0.2). The hydrophilic conditions predominate in areas with different substrates and during the winter. Observations on different scales show a decreasing RC as the size of the area increases (RC = 0.8 on the plot scale, RC = 0.5 on the hill slope scale and RC = 0.2 for the entire catchment area). The reasons for this are the hydrophilic rill in the hill slope area and the hydrophilic substrate in the entire catchment area. The measurement of erosion, based on different methods, some of them just newly developed, quantifies in a good resolution sediment transport spatially as well as temporally. The central part of one of the newly developed approaches is a balance which quantifies an event based sediment output. This approach is coupled with a tipping bucket to measure surface runoff. The system has been developed for coarse textured areas with little amounts of sand and silt. Additionally, two laser systems are used to detect changes in the soil surface over the spatial distribution. The first method contains a laser which measures only a single point and has to be moved in a fixed apparatus above the soil surface in a well defined raster. The areas of sediment abrasion and the detachment areas are restricted by interpolation of the measurement results. This method enables measurements on large areas (16 m² in this project), but tends to result in a high level of errors in the transition zone between rill and interrill. The second laser system covered an area of 1 m² in high resolution. To construct a three-dimensional picture, four different pictures have to be taken from four different directions. This defines the abrasion and detachment areas in a very detailed manner, but the method is very time-consuming and covers only a small area. In addition, measurements on the plots collected the amount of sediment output on a small scale. These results show, corresponding to the water repellent soil conditions, high rates of sediment output during summer, but low rates during winter season. The results show also the dominance of rill erosion in comparison with interrill erosion during high intensity rainfall events (>25 mm/h during one interval of ten minutes). On the contrary, interrill erosion becomes more important during low intensity rainfall events (<20 mm/h during at one interval of ten minutes). At least a 9 mm amount of precipitation with a minimum intensity of 3.6 mm/h is necessary to provoke erosion on this test site. Based on the measurement results regression empirical equations were developed to quantify surface runoff and sediment output. While, surface runoff correlates well with the amount of precipitation (r² = 0,9), sediment output shows little correlation to the amount and intensity of the precipitation (r² = 0,7). In summary, the thesis described effects of water repellent soil conditions on surface runoff and erosion on different scales. The effects on the smaller scales especially are of high interest to hydrological processes.

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