Interrill erodibility of different sandy soils increases along a catena in the Caiuá Sandstone Formation

• Autor(a) principal: Thomaz,Edivaldo Lopes
• Data de Publicação: 2020
• Outros Autores: Fidalski,Jonez
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Revista Brasileira de Ciência do Solo (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832020000100501
• topic: Hillslope; soil-geomorphology; hydropedology; conventional tillage; soil detachment

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 453 Jm2 h-1 was applied for the rainsplash tests (splash pan), whereas a rainfall intensity of 65 mm h-1 with an energy of 534 Jm2 h-1 was applied for the soil erodibility tests (using a small flume). The three soils showed differences in soil particles detached by raindrop on very fine sand class <0.15 mm as follows: Ferralsols 10 %, Arenosol 12 %, and Lixisol 15 %. The maximum soil erodibility increased gradually according to the soil position on the catena: Ferralsols (1.81 × 106 kg s m-4), Lixisols (2.83 × 106 kg s m-4), and Arenosols (3.41 × 106 kg s m-4). Finally, the position of the soil along the catena and total sand were the best in explaining soil interrill erodibility. Therefore, farmers and stakeholders should be cautious about applying a homogeneous tillage system from the summit to the foot-slope along a catena with different sandy soils.