Fauna e atributos microbiológicos de um Argissolo sob sistemas de cobertura no Sul do Brasil

Abstract

Resumo -O objetivo deste trabalho foi avaliar, em experimento de longa duração, a fauna edáfica e os atributos microbiológicos de um Argissolo Vermelho sob sistemas de cobertura em plantio direto. O trabalho foi realizado em Eldorado do Sul, RS, após 27 anos de implantação de experimento para avaliação dos seguintes sistemas de cultivo: A/M, aveia/milho; E/M, ervilhaca/milho; AE/M, aveia-preta + ervilhaca/milho; AE/MC, aveia-preta + ervilhaca/milho + feijão-caupi; e L/M, lablab/milho. Utilizou-se o delineamento de blocos ao acaso com três repetições. As amostragens da fauna edáfica, realizadas por armadilhas "pitfall", e dos atributos microbiológicos foram feitas no pós-manejo das coberturas, na primavera; durante o ciclo do milho, no verão; na pós-colheita do milho, no outono; e durante o ciclo das coberturas, no inverno. A inclusão de leguminosa em consórcio ou em sucessão de coberturas promoveu a ocorrência de organismos da fauna edáfica e aumentou C e N da biomassa microbiana, o que favoreceu o potencial de ciclagem e a disponibilidade de nutrientes. O sistema A/M de cobertura com gramíneas favoreceu as ordens Diptera, Hemiptera e Diplopoda. De forma geral, no plantio direto, os melhores sistemas de cobertura são os que incluem leguminosa.Termos para indexação: bioindicadores, biomassa microbiana, consórcio de coberturas, organismos edáficos, plantio direto, qualidade do solo. Fauna and microbial attributes of an Ultisol under cover crop systems in the South of BrazilAbstract -The objective of this work was to evaluate, in a long-term experiment, the fauna and microbiological attributes of an Ultisol under no-tillage cover crop. The study was carried out in Eldorado do Sul, RS, Brazil, after 27 years of implantation of an experiment evaluating the following crop systems: O/C, oat/corn; V/C, vetch/corn; OV/C, oat + vetch/corn; OV/CP, oat + vetch/corn + cowpea; and L/M, lablab/corn. A randomized complete block design was used, with three replicates. Samplings of fauna, performed with pitfalls, and of microbiological attributes were done after cover crop management, in spring; during corn crop cycle, in summer; after corn crop harvest, in autumn; and during cover crop cycle, in winter. The inclusion of legume intercropped or in succession to cover crops promoted the occurrence of edaphic fauna and increased microbial biomass C and N, which favored cycling potential and nutrient availability. The O/C cover crop system with grasses favored the Diptera, Hemiptera, and Diplopoda orders. Overall, the best cover crop systems under notillage are those with legume inclusion.

Grass–legume intercropping in integrated crop-livestock systems: a strategy to improve soil quality and soybean yield in the Brazilian Cerrado

“…Similar results were found byFrasier et al (2016) andLaroca et al (2018), who observed increases of C and N stocks in an experiment using grass-legume intercropping Frasier et al (2016). assigned the increase of total N stock to the better residue quality (lower C/N ratio) provided by leguminous plants Almeida et al (2016). also documented improvements in microbial biomass C and N under grass-legume intercropping systems, which may result in higher soybean yields.…”

“…The microbial biomass C and N improvements under grass-legume intercropping (Table 2) were also reported by Hurisso et al (2013) and Almeida et al (2016). The microbial biomass N increments may be due to leguminous plants insertion, which favors soil N availability through the biological N xation (Crème et al 2016).…”

Decomposition and Nutrient Release of Cover Crops in Mango Cultivation in Brazilian Semi-Arid Region

“…Absence of soil tillage or minimal tillage allows carbon (C) to accumulate in the soil due to the reduction in the organic matter decomposition rate (Conceição et al, 2013). Utilization of cover crops without soil tillage is significant because of the maintenance of soil cover, addition of nitrogen, cycling of nutrients, and reduction of soil erosion (Perin et al, 2004;Gomes et al, 2005;Lal et al, 2007;Blanco-Canqui, 2013), as well as the mitigation of greenhouse gases emissions (Bayer et al, 2015), increase in water efficiency and productivity, and increase in biological diversity, among other reasons (Espíndola et al, 2004;Almeida et al, 2016), so they can be parts of sustainable multifunctional agricultural systems.…”

Nutrient cycling in multifunctional agroecosystems with the use of plant cocktail as cover crop and green manure in the semi-arid

“…The direct influence on improving soil conditions by cover crops is the reduction of nutrient losses by leaching and erosion, maintaining of soil moisture, increasing of soil water infiltration, control of natural vegetation, supply of available nutrients and increasing biological diversity, especially when using leguminous species and improving soil structure when using grasses (Almeida et al, 2016).…”