Eficácia de espécies de cobertura na redução das perdas de água e solopor erosãoe na melhoria da qualidade física de um Latossolo argiloso

Abstract

The benefits of cover species depend on choosing the ideal plant for each region. Furthermore, legumes and grasses can differ in terms of their effects on the physical properties of the soilin short-term. Thus, the aim of this study was to evaluate the influence of cover species in summer and winter on soil physical properties, soil and water loss and corn grain yield in a clayey Oxisol in western Paraná, Brazil. The summer species were: millet (Pennisetum americanum), sunn hemp juncea (Crotalaria juncea), dwarf pigeon pea (Cajanus cajan), sunn hemp spectabilis (Crotalaria spectabilis), dwarf bean (Cajanus cajan) and black velvet bean (Mucuna pruriens). The winter species were: white oat (Avena sativa), black oat (Avena strigosa), rye (Secale cereale), forage vetch + black oat (Pisum sativum+ Avena strigosa), white lupine + black oat (Lupinus albus+ Avena strigosa), turnip+black oat (Raphanus sativus+ Avena strigosa). A treatment with traditional no-tillage system (SPD) was used as a control. The plots were artificially compacted with a compactor roller before sowing the cover species. After the cultivation ofcover species, corn was sown. The physical properties of the soil (density, macroporosity, microporosity, total porosity and hydraulic conductivity of the soil) were determined in the layers of 0-0.1, 0.1-0.2 and 0.2-0.3 m after compaction artificial (2017) and post-harvest corn (2019). Soil and water losses were determined using gutters during corn cultivation. The data obtained were statistically analyzed using a mean comparison test at 5% significance level. Cover species, white oat, rye, crotalaria juncea and crotalaria spectabilis stood out in improving the physical properties of compacted soil compared to SPD. Cover species did not reduce soil and water losses in relation to SPD in some periods, especially in times of high precipitation. The grain yield of corn cultivated after cover crops was not significantly affected.