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This research investigates the influence of layout and design on the severity of trail degradation. Previous trail studies have been restricted by relatively small study areas which provide a limited range of environmental conditions and therefore produce findings with limited applicability; this research improves on this limitation by analyzing a representative sample of the Appalachian Trail with significant ecological diversity. Most trail science studies have also focused on a singular form of trail degradation, whereas this study investigates trail soil loss, widening and muddiness, providing a more cohesive analysis and revealing interrelationships between trail degradation processes. ANOVA testing of the mean values of three trail impact indicators for trail transects within several trail layout frameworks confirms the broad relevance of core trail design principles, specifically the sustainability advantages of trails with low grades and side-hill alignments. Findings also reveal the importance of landform grade in determining the susceptibility of trails to degradation and the influence of routing decisions; these relationships have received relatively little attention in the literature. The results also reveal several methodological considerations for trail alignment metrics and trail impact indicators. / Master of Science / Natural surfaced trails are an essential infrastructure component in parks and protected natural areas. They provide transportation routes through otherwise undeveloped areas and outdoor recreation opportunities for hikers, mountain bikers, and equestrians. Over time, recreational use and natural processes such as rainfall can lead to negative ecological impacts that damage trail treads in ways that impair their utility for visitors and require costly repairs. Environmental factors like unstable soils or extreme precipitation can make trails more susceptible to degradation. However, sustainable trail layouts and effective maintenance can reduce the rate and severity of degradation. This research investigates the influence of trail layout on three chief forms of trail degradation: trail soil loss, muddiness, and widening. Many trail science studies have occurred in small protected natural areas where the limited range of represented environmental conditions reduces the applicability of their findings in dissimilar settings. This study investigates a dataset from a large and ecologically diverse representative sample of the entire Appalachian Trail from Georgia to Maine which significantly broadens the relevance of its findings. Furthermore, many previous trail studies have focused on single forms of trail degradation whereas this study which investigates three, which provides a more cohesive analysis and reveals interrelationships between impacts. Findings confirm the broad pertinence of core sustainable trail design principles, specifically the benefits of low trail grades and side-hill alignments, and suggests that landform grade is an important factor which has received little attention in the literature. The study also revealed several methodological improvements and considerations which may be useful to trail scientists and practitioners.

To date, most studies on the effectiveness of geotextiles on soil erosion rates were conducted in laboratory experiments for <1 h. Hence, at Hilton, East Shropshire, UK, this study investigated the effectiveness of palm-mat geotextiles (Borassus and Buriti mats) in reducing rainsplash erosion, runoff and soil loss and changing selected soil properties under field conditions over two years (January 2007-January 2009). Mat-cover effects on rainsplash erosion were studied in two sets on a loamy sand soil (0o slope). In both sets, six randomly-selected plots (each 1 m2) were completely matcovered and six were bare. Unlike Buriti mats, Borassus mat-cover on bare soil significantly (P<0.001) decreased rainsplash erosion (by ~89%). Duplicate runoff plots (10 x 1 m on a 15o slope) had five treatments (bare, permanent grass, Borassus completely-cover, Borassus buffer strip and Buriti buffer strip). Using Borassus buffer strips (area coverage ~10%) on bare soil decreased runoff by ~71% (P>0.05) and soil erosion by ~92% (P<0.001). Borassus buffer strip, Buriti buffer strip and Borassus completely-covered plots had similar effects in decreasing runoff and soil loss. However, the longevity of Borassus mats was ~twice that of Buriti mats. Despite physical protection, runoff control and sediment entrapment, biomat buffer zones may considerably alter and protect flow direction by presenting barriers and creating several cross-drains. Except Borassus completely-covered plots, all plots had significant (P<0.05) increases in topsoil (0-5 cm) bulk density and decreased aggregate stability. However, buffer strips were more effective in trapping fine particles than Borassus completely-covered plots. No treatments had significant (P>0.05) effects on changes in pH, soil organic matter, total soil carbon or N. Plots with Borassus mats significantly (P<0.05) increased total P and decreased total Ca. Treatments had no significant effects on changes in total S, Mg, Zn, Cu, Fe, Mn, Mo or Cl concentrations. Borassus buffer strips can effectively conserve soil and water and improve and maintain selected soil properties, with results similar to Borassus completely-covered plots. The mechanisms explaining the effectiveness of buffer zones require further studies under varied pedo-climatic conditions.

Surface mining operations require a comparison of post-mining erosion rates with pre-mining soil loss to ascertain if remedial measures are needed. In this study the Universal Soil-Loss Equation (USLE) was modified to reflect conditions of western rangelands to develop a procedure for estimating pre-mining soil loss rates. The modification used back-calculation for the C-Factor and an adjusted R-Factor based on storm size. Soil loss simulation based on stochastic precipitation patterns is appropriate to the site--the La Plata mine area in northern New Mexico--and increases the flexibility of the USLE as a soil loss predictor for western rangelands.

Um aumento considerável da área de cultivo da cana de açúcar na região central do estado de São Paulo foi verificado durante os últimos anos. A ampliação destas áreas sobre outras formas de uso e ocupação das terras na referida região proporcionam diversas alterações nos ambientes, sobretudo relacionados aos processos geomorfológicos e hidrológicos das bacias hidrográficas. Nesse sentido, estudos fundamentados em modelos matemáticos, estruturados em SIG (Sistema de Informação Geográfica) e que visem analisar o comportamento de fenômenos ambientais frente à expansão da cultura canaviera podem auxiliar órgãos públicos e privados responsáveis pelo gerenciamento e manutenção das atividades agropecuárias na região. Diante disso, o presente trabalho teve como objetivo avaliar os efeitos das alterações do uso e ocupação das terras sobre processos hidrológicos e geomorfológicos na bacia do rio Jacaré Guaçú, localizada na região central do Estado de São Paulo. Mais precisamente, verificou se as mudanças ocorridas no uso e ocupação das terras entre 1987, 2004 e 2013 influenciaram no aumento ou diminuição das perdas de solos por erosão laminar e no regime de vazão fluvial da rede de drenagem do rio Jacaré Guaçú. Dados hidrológicos, pedológicos e de Sensoriamento Remoto foram usados para estruturar em SIG o modelo matemático EUPS (Equação Universal de Perdas de Solo) e estimar as perdas de solo por erosão laminar. Técnicas de estatística foram usadas para verificar a significância nas mudanças de tendência dos dados históricos de vazão fluvial. Os resultados confirmam aumento de perdas de solo por erosão laminar acima de 15 ton. ha-1ano-1 entre 1987, 2004 e 2013. Esses valores ocorreram devido ao aumento de locais destinados à cultura temporária e com solo exposto, ambos vinculados ao cultivo da cana de açúcar. Entre o mesmo período ocorreu a diminuição de locais classificados com perdas de solo compreendidas entre 0 e 3 ton. ha-1ano-1 atrelada, sobretudo a redução de locais destinados às pastagens e com vegetação arbórea na bacia hidrográfica. As perdas de solo classificadas entre 3 e 5, 5 e 10 e 10 e 15 ton. ha-1ano-1 aumentaram entre 1987 e 2004 e diminuíram entre 2004 e 2013. A análise estatística comparativa dos dados fluviométricos evidenciou que não ocorreram mudanças significativas nos padrões de vazões médias, mínimas e máximas mensais entre 1987, 2004 e 2013. / A substantial expansion of sugarcane area in the central region of São Paulo State (Brazil) occurred in last years. The increase of sugarcane cultivation over other forms of land use implies in several changes in the environment mainly related to the geomorphological and hydrological processes in watersheds. Grounded studies on mathematical models, structured in GIS (Geographic Information System) can assist in understanding environmental changes arising the increase of sugarcane cultivation. This data can assist public and private institutions responsible for management and maintenance agricultural activities in this region. Therefore, this study aimed at evaluating the effects of changes in land use about hydrological and geomorphological processes in Jacaré Guaçú stream basin (São Paulo State - Brazil). More precisely, were analyzed the effects of changes in land use between 1987, 2004 and 2013 about laminar erosion process and Jacaré Guaçú river flow. Soil, rainfall and Remote Sensing data were used to structure the mathematical model USLE (Soil Loss Equation Universal) in the GIS (Geographic Information System) and to estimate soil loss by laminar erosion. Statistical techniques were used to evaluate changes in trends from historical data of Jacaré Guaçú river flow. The results confirmed an increase of soil loss by laminar erosion bigger then 15 t. ha-1 year -1 between 1987, 2004 and 2013 within the study area. The increase in local places with temporary culture and exposed soil, both linked to the expansion of sugarcane areas, contributed to these results. Between the same period (1987, 2004 and 2013) there was a decrease in classified locations with soil loss between 0 - 3 t. ha-1 year -1 because of area reduction with pastures and tree vegetation in hidrographic basin. Soil losses classified between 3-5, 5-10 and 10-15 t. ha-1 year -1 increased between 1987 and 2004 and decreased between 2004 and 2013. Statistical analysis showed no significant variation average, maximum and minimum of Jacaré Guaçú river flow between 1987, 2004 and 2013.

Este trabalho apresenta um estudo comparativo sobre a variação de escala (1:50.000 e 1:250.000) nas metodologias desenvolvidas por ROSS (1994) e por CREPANI (2001), na geração de cartas de fragilidade ambiental e de vulnerabilidade natural à perda do solo. Cada metodologia apresenta uma forma particular de calcular os graus de fragilidade ambiental e vulnerabilidade à perda do solo, mas ambas se baseiam no princípio da ecodinâmica de Tricart, no qual os processos de pedogênese (formadores de solo) e morfogênese (modificadores das formas de relevo) são os principais atores na classificação do meio ambiente. Nesta classificação ocorre a compartimentação do meio ambiente em áreas homólogas, o que permite o agrupamento e a síntese das informações referentes ao meio físico, como também relativas às intervenções antrópicas dentro dessas áreas. Este processo é realizado dentro de um SIG (Sistema de Informação Geográfica). O efeito da variação de escala no modelo de fragilidade ambiental possui maior representatividade para o tema geomorfologia. Os demais temas não sofrem alteração significativa, na medida em que ficam subjulgados ao índice de dissecação do relevo, sendo esta variável a determinante do grau de fragilidade de cada área. Na metodologia de Crepani a vulnerabilidade à perda do solo é decorrente da média aritmética da ponderação dos temas, de modo que, independentemente da escala, as duas cartas de vulnerabilidade à perda do solo apresentam os valores extremos (muita baixa e muito forte) atenuados, e o valor mediano preponderante. Tendo em vista que em função do menor grau de detalhamento das curvas de nível e densidade de drenagem na escala 1:250.000, quando comparadas a 1:50.000, as formas de relevo, declividade e os tipos de solos a elas associados possuem valores reduzidos de ponderação quanto à estabilidade, sendo mais brandos na escala 1:250.000 e mais marcantes na escala 1:50.000. Deste modo, as classes de fragilidade ambiental forte e muito forte são mais expressivas na escala 1:50.000, enquanto as classes fraca e muito fraca aparecem com maior frequência na escala 1:250.000. O mesmo acontece no valor da média calculada para a determinação do grau de vulnerabilidade à perda do solo, de modo que as classes alta e muito alta são mais expressivas na escala 1:50.000, enquanto as classes baixa e muito baixa aparecem com maior frequência na escala 1:250.000. / This paper presents a comparative study on the variation of scale (1:50,000 and 1:250,000) on methodologies developed by Ross (1994) and CREPANI (2001), the generation of letters of environmental fragility and vulnerability to natural soil loss . Each methodology presents a particular form of calculating the degrees of environmental fragility and susceptibility to loss of the soil, but both are based on the principle of ecodynamics Tricart, which processes pedogenesis (forming ground) and morphogenesis (modifiers landforms ) are the main actors in the classification of the environment. This classification is the partitioning of the environment in homologous areas, allowing grouping and summary information relating to the physical environment, but also related to human interventions within these areas. This process is accomplished with a GIS (Geographic Information System). The effect of variation in the scale model of environmental fragility has greater representation to the theme geomorphology. The other themes will not change significantly since become subdued by dissection index relief, and this variable determining the degree of fragility of each area. In methodology Crepani vulnerability to soil loss is due to the arithmetic average of the weighting of topics, so that, regardless of the scale, two letters of vulnerability to loss of soil present extreme values (very low and very strong) attenuated and median predominant. Considering that due to the lesser degree of detail the contours and drainage density at 1:250,000 scale, compared to 1:50,000, the landforms, slope and soil types associated with them have reduced values of weighting for stability, being more lenient on the scale 1:250,000 and 1:50,000 most striking. Thus, the classes of environmental fragility strong and very strong are more significant on the scale of 1:50,000, while the low and very low classes appear more frequently in the scale 1:250,000. The same happens on the average value calculated to determine the degree of vulnerability to loss of the soil, so that the high and very high classes are more significant 1:50,000, while classes low and very low appear most frequently in 1:250,000 scale.

Submitted by Mariana Dornelles Vargas (marianadv) on 2015-03-25T12:56:52Z No. of bitstreams: 1 analise_processos.pdf: 7156305 bytes, checksum: 71abe44755bc8859c52aee8d57799e33 (MD5) / Made available in DSpace on 2015-03-25T12:56:52Z (GMT). No. of bitstreams: 1 analise_processos.pdf: 7156305 bytes, checksum: 71abe44755bc8859c52aee8d57799e33 (MD5) Previous issue date: 2010 / Nenhuma / O planejamento do uso e ocupação do solo em uma bacia hidrográfica pode servir como um instrumento preventivo à erosão. É objeto deste estudo, detalhar o fenômeno da erosão hídrica e a produção de sedimentos na microbacia do arroio Morungava, Gravataí, RS. Esse estudo avaliou os indicadores de erosão aqui descritos como matéria orgânica e argila dos solos Argissolos e Hidromórficos, caracterizados neste estudo como perfis-tipo para a realização da caracterização pedológica. A análise quantitativa foi obtida através da coleta do horizonte superficial dos solos, que foi realizada com a aplicação do método do anel volumétrico e a análise espacializada é resultante do uso da Equação Universal de Perda de Solo (EUPS) e do emprego de técnicas dos Sistemas de Informações Geográficas (SIG?s). A avaliação da produção de sedimentos, bem como a distância e a fração deste que chega a atingir a rede de drenagem superficial foi obtida com a aplicação de equações empíricas da Taxa de Produção de Sedimentos (TPS). Os resultados mostram que os indicadores de erosão apresentam correlação, sugerindo que a fração argila exerça um efeito de proteção, reduzindo a oxidação e a perda de matéria orgânica. A erosão da microbacia é de aproximadamente 52.000 t.ano-1, sendo que destes 15.452 t.ano-1 resulta na Produção de Sedimentos (PS). A distância indicativa estimada da área de captação anual desses sedimentos pela rede hídrica é de 42 m. / Use planning and land use in basins can serve as a preventive tool to erosion. It is the object of this study, detailing the phenomenon of erosion and sediment yield in the micro basin of Morungava, Gravataí, RS. This study evaluated the erosion indicators described herein as organic matter and Clay soils and Hydromorphic soils, characterized in this study as profile types to perform the pedological characterization. The quantitative analysis was obtained by collecting the soil surface horizon, which was accomplished with the application of the volumetric ring method is spatially and analysis resulting from the use of Equation Universal Soil Loss (USLE) and the use of techniques of Geographical Information System (GIS). The assessment of sediment yield, and the distance and the fraction of that reaches the surface drainage network was obtained by applying empirical equations of Sediment Production Rate (SPR). The results show that the erosion indicators correlate, suggesting that the clay exerts a protective effect, reducing oxidation and loss of organic matter. The erosion of the watershed is approximately 52,000 t.year-1, out of which 15,452 t.year-1 results in the Production of Sediment (PS). The estimated distance indicative of the catchment area of these sediments by the annual water supply is 42 m.

The thesis is focused on the system erosion and the flood control measures in the cadastral territory of Smetanova Lhota. For the calculation of the erosion threat was used universal soil loss equation (USLE) and runoff characteristics are calculated using the runoff CN - curves. The proposal has the influence of several factors. It's rainfall, vegetation cover, soil characteristics, morphology and other. Several calculations were carried out using the program ERCN.

The aim of this work is to determine the effect of the application of catch crops in crop rotation in the cadastral territory Vrábče in Czech Budweis. Erosion washing away from the land is calculated using the USLE, also compared washing off using conventional crop rotation and intercropping with the application process. Analyze here the influence of intercropping to increase anti-erosion effect of vegetation cover. The resulting values of erosion are transported using erosion of crop rotations with intercropping significantly reduced.

Made available in DSpace on 2016-12-23T13:51:47Z (GMT). No. of bitstreams: 1 Vagner Mauri Quinto.pdf: 5674038 bytes, checksum: ead4f849dd3906c322779605ae2b29ce (MD5) Previous issue date: 2013-02-27 / The study aimed to estimate soil loss by middle of USLE in a farming area with pasture and eucalyptus of three years of age, implanted under the pasture in area declivosa in the Southern State of ES. To estimate soil loss in the study area was made a regular mesh of 33 x 33m in a area of 10,02 ha getting 94 points of sample collection. Thematic maps were elaborated of rainfall erosivity (R) for the entire State of ES in a ten year period (1999 to 2008) relative for the cultivation of pasture and three years (2009 to 2011) relative for the cultivation of eucalyptus. Were also elaborated thematic maps of soil erodibility (K) for the study area. The thematic map of the LS factor for the study area was obtained by through of combination of steepness factor and length ramp between each sample point. The factors of USLE C and P were obtained by querying literary. The occurrence likelihood of erosivity above the third quartile for the State of ES was calculated by middle of the kriging technique indicative. A descriptive analysis was performed to determine the measurements of position and dispersion data and the normality of the data were analyzed using the Kolmogorov-Smirnov test at level in 5% probability and the results related to two period of cultivation, when necessary were compared by the test Students t test at level in 5%. All granulometric fractions and content organic study matter of soil presented spatial dependence, indicating the variability of the same within the study area. In 42,7% of the study area, increased the content of organic matter content during the cultivation period of eucalyptus when compared with the pasture, however, the content showed no significant difference (p <0.05) for the two cultures. The Center-South region of the state of ES showed the values highest annual erosivity during cultivation of the two species. However, the values of erosivity in the study area were of 8.227,2 and 8.043,2 MJ mm ha-1 h-1 for the period of pasture and of eucalyptus, respectively. The K factor showed the same pattern of spatial distribution for the study area during the cultivation of two species, being the highest values obtained in the Northwest and Southwest regions. The values of soil loss ranged from 0.0 to 14.5 t ha-1 year-1 during the period cultivated of pasture and 0.0 to 3.5 t ha-1 year-1 during the period cultivated of Eucalyptus. Soil loss in the cultivation of pasture was of 74 the 77% higher than that obtained in the cultivation of eucalyptus, being average loss of 75.4%. Some municipalities presented of 91-100% of probability of occurrence of rainfall erosivity above the third quartile, being the values most critical in the months between October and April, therefore, these municipalities need to adopt conservation practices to preserve soil. The clay and organic matter presented correlated negative with PAP, DAP and AB. Thus, eucalyptus can be used for the recovery and/or regeneration of grazing areas degraded or degradation process / O estudo teve como objetivo estimar a perda de solo por meio da EUPS em uma área de cultivo com pastagem e com eucalipto de três anos de idade, implantado sob a pastagem em área declivosa no Sul do Estado do ES. Para estimar a perda de solo na área de estudo foi confeccionada uma malha regular 33 x 33m em uma área de 10,02 ha, obtendo-se 94 pontos de coleta de amostras. Foram elaborados mapas temáticos da erosividade das chuvas (R) para todo o Estado do ES em um período de dez anos (1999 a 2008) referentes ao cultivo da pastagem e três anos (2009 a 2011) referentes ao cultivo do eucalipto. Também foram elaborados mapas temáticos da erodibilidade do solo (K) para a área de estudo. O mapa temático do fator LS para a área de estudo foi obtido por meio da combinação do fator declividade e comprimento de rampa entre cada ponto amostral. Os fatores C e P da EUPS foram obtidos por meio de consulta literária. A probabilidade de ocorrência daerosividade acima do terceiro quartil para o Estado do ES foi calculada por meio da técnica de krigagem indicativa. A análise descritiva foi realizada para determinar as medidas de posição e dispersão dos dados e a normalidade dos dados foram analisadas pelo teste de Kolmogorov-Smirnov em nível de 5% de probabilidade e os resultados referentes aos dois períodos de cultivo, quando necessários foram comparados pelo teste t de Student em nível de 5%. Todas as frações granulométricas e o teor de matéria orgânica do solo em estudo apresentaram dependência espacial, indicando a variabilidade dos mesmos dentro da área de estudo. Em 42,7% da área de estudo, houve aumento do teor de matéria orgânica durante o período de cultivo do eucalipto, quando comparado com a pastagem, no entanto, os teores não apresentaram diferença significativa (p<0,05) para as duas culturas. A região Centro-Sul do Estado do ES apresentou os maiores valores de erosividade anual durante o cultivo das duas espécies. Contudo, os valores de erosividade na área de estudo foram de 8.227,2 e 8.043,2 MJ mm ha-1 h-1, para o período de cultivo da pastagem e do eucalipto, respectivamente. O fator K apresentou o mesmo padrão de distribuição espacial para a área de estudo durante o cultivo das duas espécies, sendo os maiores valores obtidos nas regiões Noroeste e Sudoeste. Os valores de perda de solo variaram de 0,0 a 14,5 t ha-1 ano-1 durante o período de cultivo da pastagem e de 0,0 a 3,5 t ha-1 ano-1 durante o período de cultivo do eucalipto. A perda de solo no cultivo da pastagem foi de 74 a 77% superior a obtida no cultivo do eucalipto, sendo a perda média de 75,4%. Alguns municípios apresentaram de 91 a 100% de probabilidade de ocorrência da erosividade das chuvas acima do terceiro quartil, sendo os valores mais críticos nos meses entre outubro e abril, portanto, esses municípios precisam adotar práticas conservacionistas para preservar o solo. A argila e a matéria orgânica apresentaram correlação negativa com o PAP, DAP e a AB. Desta forma, o eucalipto pode ser utilizado para a recuperação e/ou regeneração de áreas de pastagem degradas ou em processo de degradação