Consulta: creatorFacets:"Thomaz,Edivaldo Lopes"
Registros recuperados: 4
Data/hora: 11/06/2024 14:37:24

Rill erosion on an oxisol influenced by a thin compacted layer
Provedor de dados: 90
Autores: Thomaz,Edivaldo Lopes.
The presence of compacted layers in soils can induce subprocesses (e.g., discontinuity of water flow) and induces soil erosion and rill development. This study assesses how rill erosion in Oxisols is affected by a plow pan. The study shows that changes in hydraulic properties occur when the topsoil is eroded because the compacted layer lies close below the surface. The hydraulic properties that induce sediment transport and rill formation (i.e., hydraulic thresholds at which these processes occur) are not the same. Because of the resistance of the compacted layer, the hydraulic conditions leading to rill incision on the soil surface differed from the conditions inducing rill deepening. The Reynolds number was the best hydraulic predictor for both...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Conventional tillage; Plow-pan; Hydropedology; Surface runof; Rill erosion.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832013000500027

Interrill erodibility of different sandy soils increases along a catena in the Caiuá Sandstone Formation
Provedor de dados: 90
Autores: Thomaz,Edivaldo Lopes; Fidalski,Jonez.
ABSTRACT Soil erosion in tropical areas is a major problem for sustainability in agriculture and soil stability. In the Northwest of Paraná, cassava crop is produced using a conventional tillage system along a catena consisting of different soil classes: Ferralsols (near the summit), Lixisols (mid-slope), and Arenosols (foot-slope). Therefore, differential soil erosion rate and soil degradation are expected along the catena. Here, we test the erodibility of the three sandy soil classes in a representative catena of the Caiuá Sandstone Formation. Disturbed soil samples were collected from a depth of 0.20 m. The soil erodibility test was performed in the laboratory through a multi-drop rainfall simulator. A rainfall intensity of 55 mm h-1 with an energy of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Hillslope; Soil-geomorphology; Hydropedology; Conventional tillage; Soil detachment.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832020000100501

Runoff and sediment transport in a degraded area
Provedor de dados: 90
Autores: Thomaz,Edivaldo Lopes.
Gully erosion occurs by the combined action of splash, sheetwash and rill-wash (interrill and rill erosion). These erosion processes have a great capacity for both sediment production and sediment transport. The objectives of this experiment were to evaluate hydrological and sediment transport in a degraded area, severely dissected by gullies; to assess the hydraulic flow characteristics and their aggregate transport capacity; and to measure the initial splash erosion rate. In the study area in Guarapuava, State of Paraná, Brazil (lat 25º 24' S; long 51º24' W; 1034 m asl), the soil was classified as Cambissolo Húmico alumínico, with the following particle-size composition: sand 0.116 kg kg-1; silt 0.180 kg kg-1; and clay 0.704 kg kg-1. The approach of this...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Field measurement; Water erosion; Simulated rain; Rainsplash; Runoff.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000100025

High fire temperature changes soil aggregate stability in slash-and-burn agricultural systems
Provedor de dados: 63
Autores: Thomaz,Edivaldo Lopes.
ABSTRACT Fire is a key controlling factor in ecosystem dynamics worldwide, especially, in tropical areas under slash-and-burn agricultural systems. Farmers use fire as a tool to clean the land, and benefit from nutrient enrichment from ash-soil heating. However, fire can cause some detrimental effects on soil systems, such as organic carbon depletion, increased soil erodibility, and changes to aggregate stability. In this study, an experimental fire was applied to a plot of land following the local traditional practice of slash-and-burn. The fire temperature was monitored in the field, and its effect on soil aggregate stability was assessed. The fire temperature on soil surface was measured in four trenches, and it ranged from 355 to 660 °C (average 484 ±...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Burn severity; Prescribed fire; Soil erodibility; Marginal land; Subsistence agriculture.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162017000200157