Soil structure changes induced by tillage systems

Abstract

Structure represents one of the main soil physical attributes indicators. The soil porous system (SPS) is directly linked to the soil structure. Water retention, movement, root development, gas diffusion and the conditions for all soil biota are related to the SPS. Studies about the influence of tillage systems in the soil structure are important to evaluate their impact in the soil quality. This paper deals with a detailed analysis of changes in the soil structure induced by conventional (CT) and no-tillage (NT) systems. Three different soil depths were studied (0-10, 10-20 and 20-30 cm). Data of the soil water retention curve (SWRC), micromorphologic (impregnated blocks) (2D) and microtomographic (mCT) (3D) analyses were utilized to characterize the SPS. Such analyses enabled the investigation of porous system attributes such as: porosity, pore number and shape, pore size distribution, tortuosity and connectivity. Results from this study show a tri-modal pore size distribution (PSD) at depths 0-10 and 10-20 cm for the soil under CT and a bi-modal PSD for the lower layer (20-30 cm). Regarding the soil under NT, tri-modal PSDs were found at the three depths analyzed. Results based on the micromorphologic analysis (2D) showed that the greatest contribution to areal porosity (AP) is given by pores of round (R) shape for CT (52%: 0-10 cm; 50%: 10-20 cm; 67%: 20-30 cm). Contrary to the results observed for CT, the soil under NT system gave the greatest contribution to AP, for the upper (0-10 cm) and intermediate (10-20 cm) layers, due to the large complex (C) pore types. For the mCT analysis, several types of pores were identified for each soil tillage system. Small differences in the macroporosity (MAP) were observed for the 0-10 and 20-30 cm between CT and NT. A better pore connectivity was found for the 0-10 cm layer under NT. 2016 Elsevier B.V. All rights reserved.

Groundcover influence on physical and chemical soil properties, runoff and nutrient loss and grape yield and quality in semiarid Mediterranean vineyards

“…Nevertheless, even with higher soil compaction and similar porosity, GC doubled the infiltration rates of T. The vegetation cover, penetration resistance and infiltration scored similarly in the canonical analysis indicated that the soil compaction itself is no enough to explain the water movement in the soil. Our results agree with those from Pires et al (2017) and Gao et al (2017) which observed small differences in macroporosity, but a better pore connectivity under no tillage treatment. Thus, despite soil compaction, GC improves the water movement while not threatening the soil aeration.…”

“…GC showed low impact on soil porosity. Slight differences were observed for WHC, macro, meso, micro and total porosity and only WHC and microporosity had significant differences between CB and T. Nevertheless, GC infiltration rates doubled T. Therefore, the improvement in soil structure of GC created a new pore system with a better connectivity as other researchers found (Gao et al, 2017;Pires et al, 2017). This improvement represents a greater use of rainwater and, therefore, of water economy.…”

Water regimes and bean cultivar effects on the soil porous system characteristics

“…The soil inside the wooden beds was submitted to four regimes of soil water content (35,28,21 and 14% at volumetric basis). The treatments (cultivars and water regimes) were allotted completely randomized in a 2×4 factorial experiment with 4 replications.…”

Calidad de Andosols en sistemas forestal, agroforestal y agrícola con diferentes manejos en Zacatlán, Puebla

“…La densidad aparente baja, alta capacidad de retención de humedad y altos contenidos de amorfos y materia orgánica son comunes en Andosols (IUSS Working Group WRB, 2015); sin embargo, éstas propiedades pueden sufrir cambios irreversibles (McDaniel et al, 2012), por eliminación de la cubierta vegetal o por los diferentes sistemas de labranza. Pires et al (2017) reportaron que la porosidad total puede disminuir hasta 40% (0 a 30 cm de profundidad) de suelos sin labranza a suelos con labranza tradicional.…”