Effects of Compaction Due to Machinery Traffic on Soil Pore Configuration

Abstract

Soil compaction has been recognized as a severe problem in mechanized agriculture and has an influence on many soil properties and processes. Yet, there are few studies on the long-term effects of soil compaction, and the development of soil compaction has been shown through a limited number of soil parameters. The objectives of this study were to evaluate the persistence of soil compaction effects (three traffic treatments: T0, without traffic; T3, three tractor passes; and T5, five tractor passes) on pore system configuration, through static and dynamic determinations; and to determine changes in soil pore orientation due to soil compaction through measurement of hydraulic conductivity of saturated soil in samples taken vertically and horizontally. Traffic led to persistent changes in all the dynamic indicators studied (saturated hydraulic conductivity, K 0 ; effective macro-and mesoporosity, ε ma and ε me ), with significantly lower values of K 0 , ε ma , and ε me in the T5 treatment. The static indicators of bulk density (BD), derived total porosity (TP), and total macroporosity (θ ma ) did not vary significantly among the treatments. This means that machine traffic did not produce persistent changes on these variables after two years. However, the orientation of the soil pore system was modified by traffic. Even in T0, there were greater changes in K 0 measured in the samples taken vertically than horizontally, which was more related to the presence of vertical biopores, and to isotropy of K 0 in the treatments with machine traffic. Overall, the results showed that dynamic indicators are more sensitive to the effects of compaction and that, in the future, static indicators should not be used as compaction indicators without being complemented by dynamic indicators.

Acidentes com tratores agrícolas na Região do Alto Vale do Itajaí - SC

“…Estas tecnologias são de mesmo fabricante, e a pressão de trabalho propiciou uma distribuição uniforme das cargas, sem que o ponto de compactação máxima alcançasse valores elevados em profundidade. Soracco et al (2015) em estudo na compactação dinâmica do solo afirmam que o tráfego de máquinas influência negativamente todas as características de solo, impactando na produtividade das culturas.…”

Compactação em Latossolos e suas relações com o crescimento radicular do milho

“…Reforçando o fato de que a massa de 4 ou 10 t aliada a duas e quatro passadas de tratores não influenciou na macro do LVd. Resultado semelhante foi reportado por Soracco et al (2015) para a macro, porosidade total e Ds do Argissolo (0-0,15 m) em comparação aos tratamentos sem tráfego de máquinas agrícola, com três e cinco passadas do trator de 3,8 t. Conforme esses autores, o efeito do tráfego de máquinas não proporcionou uma energia de compactação muito extrema e por isso as alterações dessas variáveis não persistiram depois de dois anos. Discordando desses resultados Bergamin et al (2010a), afirmaram que a aplicação de maior número de passadas do trator nas camadas de 0,00-0,05 e 0,05-0,10 m acarretou a redução da macro no PDC4 e PDC6 (plantio _____ direto com compactação adicional por tráfego de trator de 5t em quatro e seis passadas, respectivamente) em 26 e 44%, respectivamente, quando comparados ao tratamento PD (plantio direto com compactação adicional).…”

Agronomic Management for Enhancing Plant Tolerance to Abiotic Stresses—Drought, Salinity, Hypoxia, and Lodging

“…Heavy traffic of agricultural machinery is responsible for surface and subsurface soil compaction [28,32], which can be prevented by the adoption of machinery tracked or wheeled with low-pressure tires.…”

“…Self-healing capacity of soils [20] Organic or inorganic soil mulching [22] Minimum tillage and no tillage [19,21] Tillage at moisture content at which the largest number of small aggregates is produced [23] Amendments: -organic matter (e.g., manure, slurry, crop residues) [24,25] -soil conditioners (polymers) [26,27] -mixing of two or more soil layers in order to reach a more equilibrated texture [28] Impact of rain and irrigation drops on bare soil surface [29] Runoff effect of rain and irrigation [29] Heavy traffic of agricultural machinery with high-volume pneumatics [28,32] Clods' exposure to freezing-thawing cycles [33] 4. The Impacts of Individual Stress Factors on Crops…”