Surface sealing and water erosion of soils with mulching in the semi-arid region of Brazil

Abstract

Evaluating soil sealing process of the semi-arid region of Brazil is important to describe this process and mitigate its effects. The objective of this work was to evaluate surface sealing and physical properties of the main soils of the Upper Ipanema watershed, in Pesqueira, Pernambuco state, Brazil, with the use of mulch. The experiment was conducted in a completely randomized design with three replications, using a 3 × 3 × 2 factorial arrangement consisted of three soil classes (abruptic Eutrophic Yellow Argissolo -AEYA, typical Eutrophic Fluvic Neossolo -TEFN, and typical Eutrophic Yellow Argissolo -TEYA), three application times of simulated rainfalls (at 0, 24, and 48 h), and two mulching conditions (with and without mulch), totaling 54 tests. Soil erosion rates, surface sealing, and resistance to penetration were evaluated. The use of mulch decreased significantly the soil water losses by 71.9% (AEYA), 62.9% (TEFN), and 41.1% (TEYA) after the first rainfall application (0 h) when compared to treatments without mulch, and promoted a higher water infiltration rate. The lowest soil resistance to penetration were found in soils with mulch. The AEYA and TEFN presented changes in porosity and migration of fine particles in the treatment without mulch. The TENF was the only soil that presented an incipient soil surface sealing layer in the treatment without mulch.

Análise da Susceptibilidade à Erosão Hídrica em uma Bacia Hidrográfica do Semiárido Brasileiro

“…Lepsch (2016) e De Queiroz et al ( 2020) ressaltam que a região semiárida do Brasil apresenta tendências a ocorrência de erosões, devido à fraca estrutura de seus solos, como também a elevada concentração de chuvas torrenciais em um curto período, provocando graves problemas ambientais como o assoreamento dos corpos hídricos superficiais. Nesse âmbito, Silva et al (2019) descrevem que além do assoreamento dos corpos hídricos, a erosão gera o empobrecimento de terras, em razão da perda da camada fértil do solo, prejuízos nas lavouras, e contribuem para o surgimento de áreas degradadas.…”

Wepp Model for Rill Erosion Estimation in a Brazilian Semiarid Watershed

“…Soil erosion is a major environmental problem in many parts of the world (EEKHOUT; VENTE, 2019). In the Brazilian semi-arid, it is one of the most serious problems threatening ecosystems, mainly in human-altered areas for their greater susceptibility to detachment and sediment transport (SILVA et al, 2019). The main impacts on these degraded areas are loss of vegetation cover and decomposed organic matter on soil surface and soil compaction due to farming practices such as overgrazing, vegetation burning, and no-till use.…”