Tillage erosion is a major contributor to the total soil erosion in cultivated topographically complex lands. No study has been carried out on tillage erosion associated with cereal-based production systems in the Canadian Prairies, and there is a need to examine tillage erosivity of secondary tillage and seeding implements and the effect of slope curvature on tillage translocation. With both tillage and water erosion occurring in a cultivated topographically complex landscape, it is valuable to investigate the relative contributions of and the possible linkage and interactions between these two erosion processes. Tillage translocation causes the mixture of subsoil into the till-layer, which may considerably affect soil properties and therefore the related biophysical processes. In this study, using plot tracers, we examined tillage translocation caused by four tillage implements: air-seeder, spring-tooth-harrow, light-cultivator and deep-tiller in southern Manitoba, Canada. We determined that secondary tillage and seeding implements could be as erosive as primary tillage implements in a cereal-based production system. In the majority of cases, tillage translocation could be explained by slope gradient alone; however, slope curvature also significantly affected tillage translocation. In two field sites in the North America Great Plains (NAGP), measured 137Cs inventories were converted into total soil erosion rates. Tillage and water erosion rates were estimated using models. The comparisons of the model estimates to 137Cs estimates showed that both tillage and water erosion significantly contributed to the total soil erosion in undulating slopes while tillage erosion was the predominant erosion process in hummocky hilltops. The contributions of and the linkage and interactions between water and tillage erosion showed predictable patterns in different landform elements, with the knowledge of which, landscape segmentation could be used to assess the potential of soil erosion. Further investigation of tillage translocation was demonstrated with four hypothetic landscapes: plane slope, symmetric hill, asymmetric hill and irregular hill, and is tested against field data. A Visual Basic coded program (TillTM) was developed to simulate the redistribution of soil constituents and soil mass. We determined that the pattern of soil mass redistribution was dependent on topography, while the pattern of soil constituent redistribution was affect by topographic features, tillage patterns and temporal scales. / February 2007

Tillage erosion is a major contributor to the total soil erosion in cultivated topographically complex lands. No study has been carried out on tillage erosion associated with cereal-based production systems in the Canadian Prairies, and there is a need to examine tillage erosivity of secondary tillage and seeding implements and the effect of slope curvature on tillage translocation. With both tillage and water erosion occurring in a cultivated topographically complex landscape, it is valuable to investigate the relative contributions of and the possible linkage and interactions between these two erosion processes. Tillage translocation causes the mixture of subsoil into the till-layer, which may considerably affect soil properties and therefore the related biophysical processes. In this study, using plot tracers, we examined tillage translocation caused by four tillage implements: air-seeder, spring-tooth-harrow, light-cultivator and deep-tiller in southern Manitoba, Canada. We determined that secondary tillage and seeding implements could be as erosive as primary tillage implements in a cereal-based production system. In the majority of cases, tillage translocation could be explained by slope gradient alone; however, slope curvature also significantly affected tillage translocation. In two field sites in the North America Great Plains (NAGP), measured 137Cs inventories were converted into total soil erosion rates. Tillage and water erosion rates were estimated using models. The comparisons of the model estimates to 137Cs estimates showed that both tillage and water erosion significantly contributed to the total soil erosion in undulating slopes while tillage erosion was the predominant erosion process in hummocky hilltops. The contributions of and the linkage and interactions between water and tillage erosion showed predictable patterns in different landform elements, with the knowledge of which, landscape segmentation could be used to assess the potential of soil erosion. Further investigation of tillage translocation was demonstrated with four hypothetic landscapes: plane slope, symmetric hill, asymmetric hill and irregular hill, and is tested against field data. A Visual Basic coded program (TillTM) was developed to simulate the redistribution of soil constituents and soil mass. We determined that the pattern of soil mass redistribution was dependent on topography, while the pattern of soil constituent redistribution was affect by topographic features, tillage patterns and temporal scales.

Tillage erosion is a major contributor to the total soil erosion in cultivated topographically complex lands. No study has been carried out on tillage erosion associated with cereal-based production systems in the Canadian Prairies, and there is a need to examine tillage erosivity of secondary tillage and seeding implements and the effect of slope curvature on tillage translocation. With both tillage and water erosion occurring in a cultivated topographically complex landscape, it is valuable to investigate the relative contributions of and the possible linkage and interactions between these two erosion processes. Tillage translocation causes the mixture of subsoil into the till-layer, which may considerably affect soil properties and therefore the related biophysical processes. In this study, using plot tracers, we examined tillage translocation caused by four tillage implements: air-seeder, spring-tooth-harrow, light-cultivator and deep-tiller in southern Manitoba, Canada. We determined that secondary tillage and seeding implements could be as erosive as primary tillage implements in a cereal-based production system. In the majority of cases, tillage translocation could be explained by slope gradient alone; however, slope curvature also significantly affected tillage translocation. In two field sites in the North America Great Plains (NAGP), measured 137Cs inventories were converted into total soil erosion rates. Tillage and water erosion rates were estimated using models. The comparisons of the model estimates to 137Cs estimates showed that both tillage and water erosion significantly contributed to the total soil erosion in undulating slopes while tillage erosion was the predominant erosion process in hummocky hilltops. The contributions of and the linkage and interactions between water and tillage erosion showed predictable patterns in different landform elements, with the knowledge of which, landscape segmentation could be used to assess the potential of soil erosion. Further investigation of tillage translocation was demonstrated with four hypothetic landscapes: plane slope, symmetric hill, asymmetric hill and irregular hill, and is tested against field data. A Visual Basic coded program (TillTM) was developed to simulate the redistribution of soil constituents and soil mass. We determined that the pattern of soil mass redistribution was dependent on topography, while the pattern of soil constituent redistribution was affect by topographic features, tillage patterns and temporal scales.

Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2018-03-07T13:14:32Z No. of bitstreams: 1 PGCS16MA147.pdf: 1188975 bytes, checksum: 7fb2079dde5dc53eb4de7d465ebc2539 (MD5) / Made available in DSpace on 2018-03-07T13:14:32Z (GMT). No. of bitstreams: 1 PGCS16MA147.pdf: 1188975 bytes, checksum: 7fb2079dde5dc53eb4de7d465ebc2539 (MD5) Previous issue date: 2016-06-23 / Water erosion is the main soil degradation factor, which is influenced by rain, soil, relief, land use and management and coverage and conservation practices. The land use, coverage and soil management is not always adequate, resulting in significant erosion due also to the lack of cultivation and conservation practices adapted systems. As a result, the water and soil loss by water erosion were quantified in Haplumbrept soil in two experiments. In one, the treatments without replicate were differentiated by doses of fertilizer applied to the soil surface in no-tillage condition. In another experiment, with a replicate, the treatments consisted of no-tillage, burned natural pasture and native pasture. In no-tillage treatments were cultivated radish, black beans, vetch, corn, oats and soybeans in rotation. Treatments with crops, with natural pasture and burned natural pasture were compared to a control treatment where the soil was kept uncultivated and unfertilized. Increases fertilizer dose applied on the soil surface cultivated by direct seeding condition increased the production of plant biomass and grain and reduced water loss and soil erosion by water. Increases fertilizer dose applied on the soil surface cultivated by direct seeding condition increased the phosphorus content in the soil surface and, thus, increased the content of the erosion sediments, but decreased the total amount of the element lost by water erosion. The loss of soil and water erosion by water related exponentially decreasing manner with the amount of fertilizer applied on the soil surface in no-tillage condition. The loss of soil by erosion is changed with the change of land use; It were lower in the native field condition, intermediate in native pasture submitted to the annual and largest growing native field in which the aerial biomass is regularly burned; water losses are not modified. The water losses by runoff are less influenced than soil loss by water erosion, both in different conditions of soil management, as in different forms of land use / A erosão hídrica é o principal fator de degradação do solo, a qual é influenciada pela chuva, solo, relevo, uso da terra e manejo e cobertura e práticas de conservação. O uso da terra, a cobertura e manejo do solo nem sempre é adequado, o que resulta em grande erosão, devido, ainda, à falta de sistemas de cultivo e de práticas conservacionistas adaptadas. Em função disso, as perdas de água e solo pela erosão hídrica foram quantificadas num Cambissolo Húmico alumínico léptico, em dois experimentos. Em um, os tratamentos, sem repetição, foram diferenciados por doses de adubo aplicado na superfície do solo em condição de semeadura direta. Em outro experimento, com uma repetição, os tratamentos consistiram de semeadura direta, campo nativo queimado e campo nativo. Nos tratamentos de semeadura direta foram cultivados nabo forrageiro, feijão preto, ervilhaca comum, milho, aveia preta e soja, em rotação. Os tratamentos com cultivo e os de campo foram comparados a um tratamento testemunha em que o solo foi mantido sem cultivo e sem adubação. O aumento da dose de adubos aplicados na superfície do solo cultivado em condição de semeadura direta aumentou a produção de biomassa vegetal e de grãos e diminui as perdas de água e solo por erosão hídrica. O aumento da dose de adubos aplicados na superfície do solo cultivado em condição de semeadura direta aumentou o teor de fósforo na superfície do solo e, com isso, aumenta o teor nos sedimentos da erosão, mas diminuiu a quantidade total do elemento perdido por erosão hídrica. As perdas de solo e de água por erosão hídrica se relacionaram exponencialmente, de modo decrescente, com a quantidade de adubos aplicados na superfície do solo em condição de semeadura direta. A perda de solo por erosão hídrica foi modificada com a mudança de uso da terra; foi menor na condição de campo nativo, intermediária em campo nativo submetido ao cultivo anual e maior em campo nativo em que a biomassa da parte aérea é regularmente queimada; as perdas de água não foram modificadas. As perdas de água por escoamento superficial foram menos influenciadas do que as perdas de solo por erosão hídrica, tanto em diferentes condições de manejo do solo, quanto, em distintas formas de uso da terra