Use of S-Index as a Structural Quality Indicator for Compacted Latosols Cultivated With Maize

Abstract

-One way to prevent soil degradation is to monitor its structural quality through physical attributes and indicators. Thus, the objective of this work was to identify parameters that can be used together with the S-index to assess the soil structural quality of Latosols-Distrophic Red Latosol (DRL) and Eutroferric Red Latosol (ERL)-cultivated with maize after traffic-induced compaction by agricultural machinery. The experiment was conducted in a randomized block design in split-plots, with five treatments and four replications for each soil class. The treatments were: T0 = conventional tillage without additional compaction; T1, T2 and T3 = one pass of a 4, 7 and 10-Mg tractor, respectively; T4 = three passes of a 10-Mg tractor. The water retention curve, density, porosity and S-index of the soil layers 0-0.1, 0.1-0.2 and 0.2-0.3 m were evaluated. The DRL presented similar S-index (0.035 to 0.037) in the T0, T1 and T2, and these S-index were connected to soil macroporosity. Most S-index of the ERL were above 0.035, except for T4 due to its higher soil density. The S-index can be used as a complementary parameter for maize height and soil macroporosity to evaluate the structural quality of DRL.Keywords: Agricultural machinery traffic. Soil management. Soil physical-water attributes. ÍNDICE S COMO INDICADOR DA QUALIDADE ESTRUTURAL EM LATOSSOLOS COMPACTADOS CULTIVADOS COM MILHORESUMO -Uma maneira de prevenir a degradação do solo é monitorar a sua qualidade estrutural por meio de atributos e indicadores físicos. Dessa forma, objetivou-se com este trabalho verificar quais parâmetros podem ser utilizados junto com o índice S para a avaliação da qualidade estrutural do solo, após a compactação induzida por tráfego de máquinas agrícolas em um Latossolo Vermelho Distrófico (LVd) e em um Latossolo Vermelho Eutroférrico (LVef), cultivados com milho. O experimento foi conduzido em delineamento de blocos casualizados em parcelas subdivididas, com cinco tratamentos e quatro repetições, para cada classe de solo. Os tratamentos foram: T0= preparo convencional sem compactação adicional; T1, T2 e T3= uma passada do trator de 4, 7 e 10 t, respectivamente; T4= três passadas do trator de 10 t. Foram avaliadas nas camadas de 0-0,10; 0,10-0,20 e 0,20-0,30 m a curva de retenção de água, a densidade, a porosidade do solo e o índice S. Os valores do índice S no LVd foram semelhantes (0,035 a 0,037) no T0, T1 e T2, os quais estiveram relacionados à macroporosidade do solo. Para o LVef, a maioria dos valores do índice S situaram-se acima de 0,035, com exceção do T4, devido aos maiores valores de densidade do solo nesse tratamento. O índice S pode ser utilizado como um parâmetro complementar a altura do milho e a macroporosidade do solo, para a avaliação da qualidade estrutural em LVd.Palavras-chave: Tráfego de máquinas agrícolas. Manejo do solo. Atributos físico-hídricos do solo.

Pedotransfer Function to Estimate the Soil Structural “S” Index and Spatial Variability in an Oxisol Within a Livestock Farming System

“…Conceptually, this index represents the slope of the line tangent to the inflection point of the SWRC. Several studies, such as Dexter (2004 a, b, c), Assis Júnior et al (2016), Magalhães et al (2018), Rossetti & Centurion (2018), have confirmed the accuracy of the S index using the soil compaction state, which is correlated with the microstructural porosity, bulk density, and soil organic matter content.…”

Large-Scale Assessment of Soil Physical Quality of Rural Settlements in the Southeast of Goiás, Brazil

“…For soils of southwest China, Xu et al [16] suggest that the S index has the potential in indicating land management in the catchment scale. S index was used to assess the structural quality of Latosols cultivated with maize [17] and of soils in the Cerrado cultivated with coffee [18].…”

EFFECT OF SOIL COMPACTION AND CO-INOCULATION WITH Azospirillum brasilense ON THE DEVELOPMENT OF PEANUT PLANTS

“…Studies aimed at understanding the ability of peanut to adapt to the most varied types of stress are important, given the global relevance of this crop. Soil compaction is a stress factor that influences the balance between macropores and micropores and total porosity (TREVISAN et al, 2017), increases soil mechanical resistance (ROSSETI, CENTURION, 2018), reduces infiltration (LOURENTE et al, 2011) and root penetration (COSTA et al, 2012), besides affecting the availability of water and nutrients to plant roots (CABRAL et al, 2012). In addition, oxygen deficiency in compacted soils causes serious problems to the biological nitrogen fixation (BNF) process, especially in the formation and activity of nodules (MOREIRA, SIQUEIRA, 2006).…”

“…In addition, oxygen deficiency in compacted soils causes serious problems to the biological nitrogen fixation (BNF) process, especially in the formation and activity of nodules (MOREIRA, SIQUEIRA, 2006). All these interferences cause changes in the biochemical functioning of crops, restricting shoot growth (FARIAS et al, 2013) and production (ROSSETI, CENTURION, 2018).…”