Made available in DSpace on 2016-12-23T14:04:34Z (GMT). No. of bitstreams: 1 Anna Paula Laje Ribeiro.pdf: 7972633 bytes, checksum: 9e24f96186dfbbafa4661a4cb1e53188 (MD5) Previous issue date: 2012-08-31 / O mecanismo de Pagamento por Serviços Ambientais é um instrumento de gestão da Política de Recursos Hídricos do estado do Espírito Santo, que tem o projeto Produtores de Água como parte integrante. Este projeto baseia-se na conservação do solo para melhoria/conservação da qualidade das águas dos cursos d água e, para tanto, oferece uma compensação financeira àqueles que preservam ou reconstituem a vegetação das matas ciliares de estratégicas bacias hidrográficas do estado. A formulação deste projeto baseia-se, de forma simplificada, metodologicamente, em alguns fatores componentes da EUPS como parâmetros técnicos para determinação dos coeficientes de valoração. Nesse sentido, o presente trabalho tem por objetivo propor o aperfeiçoamento metodológico do emprego da EUPS no desenvolvimento do citado projeto. Para isso, os seguintes aspectos foram considerados e avaliados: utilização de ferramentas de geoprocessamento não utilizada pela metodologia atual; formulações para cálculo do fator topográfico LS mais condizentes com a realidade a metodologia vigente adota apenas três valores médios para a declividade S (32,5%, 60,0% e 87,5%), desconsidera valores de declividade inferiores a 20% e toma L como constante e igual a 100 metros; adoção de valores para o fator CP relativos a uso e manejo conservacionistas do solo a versão metodológica em vigor volta-se apenas para a conservação de florestas; e emprego do produto RK como fator de relativização espacial do esforço potencial para a redução de perda de solo na propriedade a metodologia vigente não analisa esse produto. No desenvolvimento do estudo foram utilizadas as três bacias hidrográficas em que o projeto Produtores de Água foi aplicado em sua fase experimental e 30 propriedades selecionadas das 197 que formaram o banco de dados do projeto em maio de 2011. Entre os resultados do estudo comparativo envolvendo a metodologia atual do projeto e metodologias visando seu aperfeiçoamento, têm-se: que há bastante diferença entre as duas técnicas abordadas de LS (calculado pela metodologia atual poderá ter seu valor subdimensionado ou superdimensionado se, respectivamente, o relevo for íngreme/plano) e, tomando a metodologia proposta como mais adequada, evidenciou-se o seu uso; o fator CP, quando da alteração do tipo de uso do solo mostrou-se bastante eficaz para reduzir a perda de solo potencial, entretanto, não foi sensível a análise desta característica no processo de evolução entre os estágios de regeneração florestal (capoeira, macega e vegetação secundária avançada/mata nativa); e o fator RK ressaltou que o distanciamento entre as propriedades impacta diretamente em sua variação, mostrando-se uma ferramenta importante de relativização espacial. No mais, foram propostas diretrizes para viabilizar a aplicação destes resultados em iniciativas de PSA, principalmente, no projeto Produtores de Água / The mechanism of Payment for Environmental Services is a management tool in water resources policy of the state of Espírito Santo, which has the project Produtores de Água as part of this. This project is based on soil conservation for improvement/maintenance of water quality of streams and, therefore, offers financial compensation to those that preserve or reconstruct the vegetation of the riparian forest of strategic watersheds in the state. The formulation of this project is based, in simplified form, methodologically, in some components of the USLE factors as technical parameters for determining the coefficients of valuation. Accordingly to these factors, this paper aims to propose a methodological improvement of the use of USLE in the development of that project. For this, the following aspects were considered and evaluated: use of GIS tools - not used by the current methodology, formulas for calculating the topographic factor LS more consistent with reality - the current methodology takes only three average values for the slope S (32.5%, 60.0% and 87.5%), ignores values less than 20% slope and take L to be constant and equal to 100 meters; adoption of CP values for the factor relating to the use and conservation management of soil - the version methodological back in force only for the conservation of forests, and RK use of the product as a factor of relativity space effort to reduce potential soil loss on the property - the current methodology does not review this product. In developing of this study, we used the three watersheds in what the project Produtores de Água was applied in its experimental phase and 30 of the 197 selected properties that formed the database of the project in may 2011. Among the results of a comparative study involving the current methodology of the project and methodologies aimed at improving it, follows that: that there is enough difference between the two techniques discussed in the LS (calculated using the current methodology may have its value be undersized or oversized, respectively, topography is steep / flat), and taking the proposed methodology as more appropriate, there was its use, the CP factor when changing the type of land use proved to be very effective in reducing soil loss potential, however , was not sensitive analysis of this feature in the evolution process between stages of forest, and factor RK noted that the distance between the properties directly impacts on their variation, being an important tool of relativity space. Other than that, guidelines were proposed to enable the implementation of these initiatives results in PES, especially in the design of Produtores de Água

Submitted by CARLA MARIA GOULART DE MORAES (carlagm) on 2015-04-23T20:17:19Z No. of bitstreams: 1 MarciaGomesGeologia.pdf: 3212123 bytes, checksum: 2a235d35b0c87594b8e37e68a2ffd53b (MD5) / Made available in DSpace on 2015-04-23T20:17:19Z (GMT). No. of bitstreams: 1 MarciaGomesGeologia.pdf: 3212123 bytes, checksum: 2a235d35b0c87594b8e37e68a2ffd53b (MD5) Previous issue date: 2009-09-15 / Nenhuma / A degradação dos solos é um dos principais problemas relacionados ao desenvolvimento sustentável, e um dos grandes desafios a serem enfrentados já neste século. A ação do homem no planejamento e desenvolvimento da ocupação do espaço na Terra requer cada vez mais uma visão ampla sobre as necessidades da população, os recursos terrestres e aquáticos disponíveis e o conhecimento sobre o comportamento dos processos naturais, para racionalmente compatibilizar necessidades crescentes com recursos limitados. A crescente degradação do solo sob exploração agrícola em todo o mundo despertou nos últimos anos uma preocupação com a qualidade do solo e a sustentabilidade da produção agrícola. A matéria orgânica do solo é um fator relevante na qualidade deste, sendo uma fonte de energia, de carbono e doadora de elétrons da grande maioria dos organismos, o que evidencia sua importância para a biota desempenhar suas funções no sentido de promover as propriedades do solo. O objetivo deste trabalho é avaliar a degradação do solo na microbacia do arroio Morungava, com uso da Equação Universal de Perda de Solo (EUPS), através de análise da variação temporal da matéria orgânica nos horizontes superficiais, em solos Hidromórficos e Argissolos, sob práticas de cultivo em diferentes períodos de uso (18 meses de cultivo; 10 anos de cultivo; 15 anos de cultivo e mais de 30 anos de cultivo), utilizando áreas de mata nativa como referência. Em condições naturais os argissolos mostram um aumento de matéria orgânica (MO) com a profundidade. Nos horizontes superficiais dos solos cultivados analisados observa-se perda de MO por erosão e oxidação superficial, com pouca translocação vertical. Neste caso, a erosão superficial acelerada antropicamente, faz com que o Horizonte B dos argissolos fique próximo a superfície, eventualmente exposto, com o passar do tempo. Já os solos hidromórficos verificam-se grandes perdas iniciais com a retirada de matas nativas, o que pode ser em parte atribuído à oxidação acelerada da MO, devido às mudanças ambientais. Para os solos hidromórficos com mais de 15 anos de uso, verifica-se um comportamento inverso, ocorrendo um significativo aumento superficial da MO, o que pode ser devido ao aporte de MO originado dos argissolos adjacentes. Assim, as planícies aluvionares, para tempos de uso superiores há 15 anos, devem provavelmente atuar como zonas de acumulação de MO na bacia hidrográfica. Há um provável processo menos intenso de translocação vertical, o qual é observado nos primeiros 10 anos de uso dos hidromórficos. Quanto à avaliação espacial de perda de MO observa-se taxas com variação de 0 até 239,15 t ha¯¹ ano¯¹ com o uso do solo atual. Assim, 54,12 % da área apresentam taxas de perda de MO entre 0 a 0,5 t ha¯¹ ano¯¹ 42,21 % variam de 0,5 a 5 t ha¯¹ ano¯¹e os demais 3,67 % de área apresentam perdas de MO acima de 5 t ha¯¹ ano¯¹. Em um cenário onde a legislação ambiental (Código Florestal Federal - Lei 4.771 de 1965 e Código Florestal Estadual - Lei 9.519 de 1992) é cumprida, com reflorestamento nas Áreas de Preservação Permanente ? APPs, referente às encostas com declividade acima de 45º e faixas de 30 metros de cada lado, ao longo dos cursos d´água, observa-se 62,17 % da área com taxas de perda de MO entre 0 a 0,5 t ha¯¹ ano¯¹, 36,86 % variam de 0,5 a 5 t ha¯¹ ano¯¹e os demais 0,97 % de área apresentam perdas de MO acima de 5 t ha¯¹ ano¯¹, chegando a atingir 37,28 t ha¯¹ ano¯¹em alguns pontos. Para um cenário onde a faixa de preservação é de apenas 5 metros de cada lado, ao longo dos cursos d´águas, de acordo com a legislação ambiental do Estado de Santa Catarina (Art. 114 da Lei Estadual 14.675, de 13 abril de 2009), observa-se que as taxas de perda de MO aumentam. No cenário anterior as perdas acima de 5 t ha¯¹ ano¯¹, atingem apenas 0,97% do total da área. Aplicando a legislação do Estado de Santa Catarina, as taxas de perda acima de 5 t ha¯¹ ano¯¹, atingem 1,03 % do total da área. As taxas baixas de perda de MO (abaixo de 0,5 t ha¯¹ ano¯¹) para o cenário de 30 metros de preservação chegam a 62,17% da área. Já no cenário com faixa de preservação de apenas 5 metros, as taxas baixas de perda de MO chegam a 53,16% da área. Apesar de ser uma diferença pequena de taxas de perda de MO, estas taxas apresentadas comprovam que a diminuição das faixas de preservação de 30 metros para cinco metros, acarretará em prejuízos ao meio ambiente. Em um cenário onde toda a faixa de preservação de 30 metros de cada lado, ao longo dos cursos d´água, é retirada, as taxas de perda de MO variam de 0 até 239,15 t ha¯¹ ano¯¹. Neste caso 53,16 % da área apresenta taxas de perda de MO entre 0 a 0,5 t ha¯¹ ano¯¹, 43,02 % variam de 0,5 a 5 t ha¯¹ ano¯¹ e 3,82 % de área apresentam perdas de MO acima de 5 t ha¯¹ ano¯¹, chegando a atingir 239,15 t ha¯¹ ano¯¹ em alguns pontos. Essas taxas de perda são equivalentes ao uso do solo atual da área. Isto ocorre pelo fato da microbacia do arroio Morungava apresentar grandes extensões de faixa de preservação ao longo desses cursos d´água, totalmente desmatadas. O cenário criado para desmatamento de 30 metros é semelhante à situação real da área. A partir dos resultados obtidos das coletas de campo e dados gerados em laboratório, conclui-se que a micro bacia do arroio Morungava está sofrendo processo erosivo acelerado com o decorrer dos anos, principalmente em zonas de maior declividade, onde predominam os argissolos. Já os solos em posição fisiográficas com baixa erosão potencial superficial, como os hidromórficos, atuam como zonas de acumulação de sedimentos e matéria orgânica. Verifica-se uma variação ampla nas taxas de perda de MO com o uso do solo atual, com teores elevados nas áreas com maior declividade. Estes teores, de acordo com cenários gerados de reflorestamento, podem diminuir com o cumprimento da legislação ambiental. Assim pode-se afirmar que a EUPS foi fundamental para avaliar a perda de matéria orgânica na microbacia. / Soil degradation is one of the main concerns regarding sustainable development, and one of the challenges to be faced on this century. Mankind actions on planning and development of Earth occupation, needs more and more a broader view of population needs, available terrestrial and hydric resources and knowledge over natural processes behavior, to rationally conciliate growing needs with limited resources. The worldwide growing soil degradation due to agricultural exploitation, over the last years awoke a concern with soil quality and agricultural production sustainability. The soil organic matter is a relevant factor for its quality, being energy and Carbone source and an electron donator to most organisms, which only shows how it is important to biota?s functions and promote soil proprieties. The objective of this study is to evaluate the soil degradation at the micro basin of the Morungava stream, using the Universal Soil Loss Equation (USLE), through temporal variation analysis of organic matter on superficial horizons, on hydromorphic and argillaceous soils, under cultivation on different usage periods (18 months of cultivation, 10 years of cultivation, 15 years of cultivation and more than 30 years of cultivation), utilizing areas of native forest as reference. In natural conditions argillaceous soils show an increase in organic matter (OM) as it deepens. On the analyzed cultivated soils superficial horizons, was observed a loss of OM due to erosion and superficial oxidation, with low vertical translocation. In this case, the superficial erosion hasten by anthropic influence, causes the B horizon of argillaceous soils to be near the surface, eventually exposed with time. On the hydromorphic soils, there are big initial losses with the removal of native forests, which can be in part caused by hasten oxidation of OM due to environmental changes. To hydromorphic soils with more than 15 years of usage, a inverse behavior is observed, occurring a significant increase of superficial OM, which can be due to the arrive of OM from the adjacent argillaceous soils. So, the alluvial plains, to usage periods greater than 15 years, probably act as OM accumulation zones on the basin. There is a probable process less intense of vertical translocation, which is observed during the first 10 years of hydromorphic soil usage. As for the spatial evaluation of OM loss, its observed with variation from 0 to 239,15 t.ha¯¹.year¯¹ with current soil usage. This way, 54,12% of the area presents OM loss rate between 0 and 0,5 t.ha¯¹.year¯¹, 42,21% varies from 0,5 to 5 t.ha¯¹.year¯¹, and the remaining 3,67% of the area show OM losses superior to 5 t.ha¯¹.year¯¹. In a scenery where the environmental legislation (Federal Forest Code ? Law 4.771 of 1965 and State Forest Code ? Law 9.519 of 1992) is followed, with reforesting of Permanent Preservation Areas (APPs), referring to acclivity superior to 45° and a 30 meters preservation band from the margins of any watercourse, is observed that 62,17% of the area have a OM loss rate between 0 and 0,5 t.ha¯¹.year¯¹, 36,86% varies from 0,5 to 5 t.ha¯¹.year¯¹ and the remaining 0,97% have a OM loss rate superior to 5 t.ha¯¹.year¯¹, peaking 37,28 t.ha¯¹.year¯¹ at some points. In a scenery where the preservation band is only 5 meters from the margin of watercourses, in accordance with the environmental legislation of Santa Catarina state (Art.114 State Law 14.675 from 2009, April 13), its observed an increase in the OM loss Rates. If in the previous scenery the OM losses over 5 t.ha¯¹.ano¯¹, were only 0,97% of total area, applying the Santa Catarina State Law, the OM losses over 5 t.ha¯¹.ano¯¹, are 1,03% of total area. The low OM loss rates (under 0,5 t.ha¯¹.ano¯¹,) on the 30 meters preservation scenery were 62,17% of the area, applying the Santa Catarina state 5 meters preservation scenery it drops to 53,16% of the area. Even if it is a small difference on OM loss rates, these rates testify that the reduction of the preservation bands will incur in harm to the environment. In a scenery where all the preservation band is removed along the watercourses, the OM loss rates varies from 0 to 239,15 t.ha¯¹.year¯¹. In which case 53,16% of the area presents OM loss rates from 0 to 0,5 t.ha¯¹.year¯¹, 43,02% varies from 0,5 to 5 t.ha¯¹.year¯¹ and 3,82% of the area show OM losses over 5 t.ha¯¹.year¯¹, peaking 239,15 t.ha¯¹.year¯¹ at some points. Those loss rates are equivalent to those of the current soil usage in this area. This is due to the fact that the micro basin of the Morungava stream presents great extensions of preservation bands along its watercourses totally depleted. The scenery created with no preservation band is similar to the current situation of the area. From the gotten results of the collections of field and data generated in laboratory, one concludes that the micro basin of the Morungava stream is suffering sped up erosive process with elapsing of the years, mainly in zones of bigger declivity, where the argissolos predominate. Already the ground in position fisiográficas with low superficial potential erosion, as the hidromórficos, act as zones of accumulation of sediments and organic matter. An ample variation in the taxes of loss ME with the use of the ground is verified current, with texts raised in the areas with bigger declivity. These texts, scenes in accordance with generated of reforestation, can diminish with the fulfilment of the ambient legislation. Thus it can be affirmed that the EUPS was basic to evaluate the loss of organic matter in the micron basin.

Der Einfluss bodenspezifischer Größen auf die Rillenerosion wurde in Überströmungsversuchen in einem eigens dafür konstruiertem Kleingerinne untersucht. Die Neigung des 2 m langen und 0,1 m breiten Gerinnes wurde dafür zwischen 2, 4 und 6 % variiert. Im Gerinne wurden zum einen natürliche Böden, zum anderen künstliche, aus Schluff und Sand gemischte Substrate mit 0,060 l*s-1, 0,125 l*s-1 und 0,300 l*s-1 überströmt. Die Körnung der natürlichen Böden reichte von stark schluffig bis sandig-lehmig, die der künstlichen Substrate von stark schluffig bis sandig. Die künstlichen Substrate wiesen im Gegensatz zu den natürlichen Böden keine Aggregierung auf und waren frei von organischer Substanz. Zu Beginn der Versuche wird der Boden zunächst flächig überströmt. Währenddessen bilden sich Mikrorillen auf der Gerinnesohle aus. Selektiver Sedimenttransport bewirkt die Akkumulation der nicht transportablen Fraktion auf der Bodenoberfläche, wodurch sich Rippel bilden. Über den Rippeln formen sich stehende Wellen im Abfluss. Die stehenden Wellen erzeugen Sohlschubspannungsspitzen auf die Gerinnesohle, welche zu verstärkter lokaler Erosion, zur Ausbildung von Mikrodepressionen und im weiteren zur Entstehung von Rillenköpfen führen. Die Rillenköpfe wandern entgegen dem Gefälle und hinterlassen Rillen, in denen sich der Abfluss konzentriert. In den Rillen können weitere Rillenköpfe entstehen. Anhand des Beginns der Rillenerosion, der Rillenkopfneubildungsrate, dem Erosionsfortschritt der Rillenköpfe, der Bestandsdauer der Rillenköpfe und der Sedimentkonzentration im Abfluss kann das Phänomen „Rillenerosion“ erfasst und quantifiziert werden. Diese erosionsspezifischen Kennwerte zeigen sich dabei in Abhängigkeit von bodenspezifischen Größen, wie der Lagerungsdichte, der Korngrößenzusammensetzung sowie der Aggregatgrößenverteilung und –stabilität. Aus den Korrelationsanalysen zwischen den bodenspezifischen Größen und den spezifischen Kennwerten der Rillenerosion leiten sich empirische Beziehungen ab. Diese Beziehungen sind nicht-linearerer und nicht-stetiger Natur. Parallel zu den Versuchen im Kleingerinne wurden Überströmungs- und Beregnungsversuche in einem Großgerinne durchgeführt. Die Projektion der laborativen Ergebnisse des Kleingerinnes auf das naturnahere Großgerinne zeigte dabei Parallelen.

From the Proceedings of the 1975 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 11-12, 1975, Tempe, Arizona / The universal soil loss equation (USLE) is widely used for estimating annual and individual storm erosion from field-sized watersheds. Records from a single precipitation gage in climatic areas dominated by thunderstorms can be used to estimate the erosion index (EI) only for the point in question on individual storms or for a specific annual value. Extrapolating the results for more than about a mile leads to serious error in estimating the erosion by the use of the USLE. Short time intervals must be used to obtain an adequate estimate of the EI when using the USLE. The variability of the annual EI can be approximated with a log-normal distribution. All studies indicated that investigations are needed to facilitate estimating the average annual EI from precipitation data as reported by state climatological summaries for states west of the 104th meridian. Additional work is needed to facilitate estimating the EI value from the precipitation data available in most areas of the southwest where thunderstorms dominate the rainfall pattern.

Accelerated soil erosion is drawing a growing attention with the recognition that the rate of soil loss is too great to be met by soil formation rate. Weenen Game Reserve (WGR) is an area with an unfortunate history of prolonged soil erosion due to excessive overgrazing that led to severe land degradation with prominent visible scars. This problem triggered the general objective of estimating and mapping potential soil erosion in WGR. Assessing soil loss in the area objectively has important implications for the overall management plans as it is reserved for ecological recovery. The most important variables that affect soil erosion are considered as inputs in soil loss estimation models. In this study the RUSLE model, which uses rainfall, soil, topography, and cover management data, was employed. From the rainfall data, an erosivity factor was generated by using a regression equation developed by relating EI30 index and total monthly rainfall. The soil erodibility factor was calculated using the soil erodibility nomograph equation after generating the relevant data from laboratory analysis of soil samples gathered from the study area. Using exponential ordinary kriging, the point values of this factor were interpolated to fill in the non-sampled areas. The topographic effect, which is expressed as the combined impact of slope length and slope steepness, was extracted from the DEM of the study area using the flow accumulation method. For mapping of the land cover factor, in situ measurements of cover from selected sites were undertaken and assigned values from the USLE table before being related with MSAVI of Landsat 7 ETM+ image. These values were then multiplied to get the final annual soil loss map. The resulting potential soil loss values vary between 0 and 346 ton ha-1 year-l with an average of 5 ton ha-1 year-l. About 58% of the study area experiences less than 1 ton ha-1 year-1 indicating the influence of the highest values on the average value. High soil erosion rates are concentrated in the central part extending as far as the south and the north tips along the eastern escarpments and these areas are the ones with the steepest slopes. The results indicate a high variation of soil loss within the study area. Nevertheless, the majority of the area falling below the average might foresee that the soil erosion problem of the area can be minimized significantly depending largely on soil management. The most important areas for intervention are the medium and low erosion susceptible parts of WGR, which are mainly found in the flatter or gently sloping landscapes. The steepest areas are mostly covered with rocks and/or vegetation and hence less effort must be spent in managing them. Overall, the reported increasing density of the vegetation community in the area that reduces the exposure of soil from the impact of direct raindrops and surface-flowing water must be pursued further. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2004.

The aim of this work is to explore the area of the Complex Land Consolidation Poněšice in the view of the pedology, hydrogeology and climatology. Further make a erosion threat calculations using the USLE and Curve Number method and afterwards review the application of the erosion control measures in another section of the chapter Main terriorial systems. In conclusion, to estimate the economic aspects of the proposed measures.

Annotation Erosion is a chronic problem in both agricultural and nonagricultural land. Its has an inconsiderable effect on overall stability of landscape. In the case of farming management on agricultural soils the risk of erosive processes increases severalfold. In foothill and mountain areas with dominance of slopes and hills the soil loss during higher maximum 24hrs N-rainfalls can reach up to several tons per hectare. This work deals with the evaluation of soil erosion vulnerability in selected catchment {--} Ostrice catchment {--} in the Lipno reservoir area. The CN method was used for calculations and following evaluation of soil loss.

The contents of this thesis is an examination and assessment of erosion processes in the catchment Budského stream. The area of interest falls into three cadastral territory, Malče, Besednice a Soběnov. Catchment area is 7.1 km2. Integral part of work is the pedological and hydrological research. It was evaluated the impact of waste in the surrounding villages. In the catchment basin, has a significant influence Besednice reservoir. It was assessing its impact on the environment and erosion control functions. Using the acquired information has been calculated N-year water and the amount of drifted soil by Wischmeier and Smith. Another goal is to process this data using software modeling and evaluate output. Against this background and the results are recommended measures to reduce soil loss from these plots.

From the Proceedings of the 1974 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 19-20, 1974, Flagstaff, Arizona / An erosion prediction method that has recently received wide attention in the United States is the universal soil loss equation which is given as: a=rklscp. Where a = estimated soil loss (tons/acre/year), r = a rainfall factor, k = a soil erodibility factor, l = a slope length factor, s = a slope gradient factor, c = a cropping-management factor, and p = an erosion control practice factor. Data collected on the walnut gulch experimental watershed in southeastern Arizona were used to estimate these factors for semiarid rangeland conditions. The equation was then tested with data from watersheds of 108 and 372 acres. The predicted value of annual sediment yield was 1.29 tons/acre/year as compared with an average 1.64 tons/acre/year for 4 years of data for the 108-acre watershed, and a sediment yield of 0.39 tons/acre/year was predicted for the 372-acre watershed as compared with the measured value of 0.52 tons/acre/year. Although good agreement was noted between predicted and actual sediment yield, additional work is needed before the equation can be applied to other areas of the southwest.

Die Dissertation erforscht die Unsicherheit, Sensitivität und Grenzen großskaliger Erosionsmodelle. Die Modellierung basiert auf der allgemeinen Bodenabtragsgleichung (ABAG), Sedimenteintragsverhältnissen (SDR) und europäischen Daten. Für mehrere Regionen Europas wird die Bedeutung der Unsicherheit topographischer Modellparameter, ABAG-Faktoren und kritischer Schwebstofffrachten für die Anwendbarkeit empirischer Modelle zur Beschreibung von Sedimentfrachten und SDR von Flusseinzugsgebieten untersucht. Der Vergleich alternativer Modellparameter sowie Kalibrierungs- und Validierungsdaten zeigt, dass schon grundlegende Modellentscheidungen mit großen Unsicherheiten behaftet sind. Zur Vermeidung falscher Modellvorhersagen sind kalibrierte Modelle genau zu dokumentieren. Auch wenn die geschickte Wahl nicht-topographischer Algorithmen die Modellgüte regionaler Anwendungen verbessern kann, so gibt es nicht die generell beste Lösung. Die Ergebnisse zeigen auch, dass SDR-Modelle stets mit Sedimentfrachten und SDR kalibriert und evaluiert werden sollten. Mit diesem Ansatz werden eine neue europäische Bodenabtragskarte und ein verbessertes SDR-Modell für Einzugsgebiete nördlich der Alpen und in Südosteuropa abgeleitet. In anderen Regionen Europas ist das SDR-Modell bedingt nutzbar. Die Studien zur jährlichen Variabilität der Bodenerosion zeigen, dass jahreszeitlich gewichtete Niederschlagsdaten geeigneter als ungewichtete sind. Trotz zufriedenstellender Modellergebnisse überwinden weder sorgfältige Algorithmenwahl noch Modellverbesserungen die Grenzen europaweiter SDR-Modelle. Diese bestehen aus der Diskrepanz zwischen modellierten Bodenabtrags- und maßgeblich zur beobachteten bzw. kritischen Sedimentfracht beitragenden Prozessen sowie der außergewöhnlich hohen Sedimentmobilisierung durch Hochwässer. Die Integration von nicht von der ABAG beschriebenen Prozessen und von Starkregentagen sowie die Disaggregation kritischer Frachten sollte daher weiter erforscht werden. / This dissertation thesis addresses the uncertainty, sensitivity and limitations of large-scale erosion models. The modelling framework consists of the universal soil loss equation (USLE), sediment delivery ratios (SDR) and European data. For several European regions, the relevance of the uncertainty in topographic model parameters, USLE factors and critical yields of suspended solids for the applicability of empirical models to predict sediment yields and SDR of river catchments is systematically evaluated. The comparison of alternative model parameters as well as calibration and validation data shows that even basic modelling decisions are associated with great uncertainties. Consequently, calibrated models have to be well-documented to avoid misapplication. Although careful choices of non-topographic algorithms can also be helpful to improve the model quality in regional applications, there is no definitive universal solution. The results also show that SDR models should always be calibrated and evaluated against sediment yields and SDR. With this approach, a new European soil loss map and an improved SDR model for river catchments north of the Alps and in Southeast Europe are derived. For other parts of Europe, the SDR model is of limited use. The studies on the annual variability of soil erosion reveal that seasonally weighted rainfall data is more appropriate than unweighted data. Despite satisfactory model results, neither the careful algorithm choice nor model improvements overcome the limitations of pan-European SDR models. These limitations are related to the mismatch of modelled soil loss processes and the relevant processes contributing to the observed or critical sediment load as well as the extraordinary sediment mobilisation during floods. Therefore, further research on integrating non-USLE processes and heavy-rainfall data as well as on disaggregating critical yields is needed.