Effects of soil water hysteresis and the direction of sampling on aeration and pore function in relation to soil compaction and tillage

doi:10.1016/0167-1987(94)90032-9

Soil and Tillage Research

Volume 32, Issue 1, October 1994, Pages 51-60

https://doi.org/10.1016/0167-1987(94)90032-9 Get rights and content

Abstract

Cores of intact soil were taken in vertical and horizontal directions in two tillage experiments from horizons subjected to compaction. Cores from below the plough layer were equilibrated at a range of matric potentials by drainage. Cores from near the soil surface were subjected to hysteresis by drainage to −2 kPa from saturation, further drainage to − 10 kPa and finally re-wetting to − 2 kPa. Air-filled porosity, relative diffusivity, diffusion time delay and air permeability were measured at each potential, and pore continuity and pore organisation indices were calculated. Diffusion time delay is a measure of the time taken for gas to diffuse across a core at the beginning of a measurement of diffusion.

Hysteresis influenced both air-filled porosity and the relationships between air-filled porosity and gas diffusivity and air permeability. Soil aeration was generally more favourable after wetting to − 2 kPa from − 10 kPa than after drainage to − 2 kPa from saturation. Hysteresis effects were greater in ploughed than in direct drilled soils. Direction of sampling influenced diffusion and flow properties, mainly in compact direct drilled soil from near the surface. These effects were partly attributed to the sampling method but gave evidence of greater vertical than horizontal orientation of macropores in ploughed soil and greater horizontal than vertical orientation of macropores in direct drilled soil.

References (20)

B.C. Ball et al.
Straw incorporation and tillage methods: straw decomposition, denitrification and growth and yield of winter barley
J. Agric. Eng. Res.
(1990)
B.C. Ball et al.
Soil structural and transport properties associated with poor growth of oil seed rape in soil direct drilled when wet
Soil Tillage Res.
(1994)
B.C. Ball et al.
Cultivation and nitrogen requirements for continuous winter barley on a gleysol and a cambisol
Soil Tillage Res.
(1989)
P.S. Blackwell et al.
Compaction of a silt loam soil by wheeled agricultural vehicles. 1. Effects upon soil conditions
Soil Tillage Res.
(1986)
P. Bullock et al.
Porosity aspects of the regeneration of soil structure after compaction
Soil Tillage Res.
(1985)
D.J. Campbell et al.
Controlled seedbed traffic after ploughing or direct drilling under winter barley in Scotland, 1980–1984
Soil Tillage Res.
(1986)
F.B. Ellis et al.
Direct drilling, shallow tine-cultivation and ploughing on a silt loam soil, 1974–1980
Soil Tillage Res.
(1982)
J.R.M. Arah et al.
A functional model of soil porosity based on measurements of gas diffusion
Eur. J. Soil Sci.
(1994)
B.C. Ball et al.
A laboratory method to measure gas diffusion and flow in soil and other porous materials
J. Soil Sci.
(1981)
B.C. Ball et al.
Gas diffusion, fluid flow and derived pore continuity indices in relation to vehicle traffic and tillage
J. Soil Sci.
(1988)

There are more references available in the full text version of this article.

Cited by (16)

Effect of cover crops on hysteresis and anisotropy of soil hydraulic properties
2022, Geoderma Regional
Citation Excerpt :
Other authors obtained the wetting curve from disturbed samples by adding increasing volumes of water in separate samples and measuring the tension once they were in equilibrium (Brantley et al., 2015; Brye, 2003). Ball and Robertson (1994) obtained the drying and wetting curves on a tension table in the range of 0 to 1 m of h on undisturbed samples. Konyai et al. (2006) obtained the scanning wetting curve in the same range of h using the hanging column method on undisturbed soil samples.
No till is the main management system for soil conservation world-wide. In Argentina is frequently implemented in simplified crop sequences, which has negative effects on soil physical quality (SPQ). Among the suggested practices to preserve the physical fertility of soils under no till have been cited winter cover crops (CC). Generally, the estimation of pore distribution parameters and capacity SPQ indicators has been conducted from the relationship between water content (θ) and matric potential (h) obtained from desorption experiments. However, the water retention curve is considered as hysteretic. The objectives of this study were to incorporate the wetting curve (WWRC) to assess the impact of the incorporation of rye (Secale cereale L.) as CC on hydraulic properties in the first 10 cm of a Typic Hapludol and to analyze if the values are affected according to the sampling direction. The incorporation of CC increased the hysteretic behavior in the near and the medium saturation region. The sample direction did not affect significantly any capacity indicators, manifesting the isotropic character of the porosity. The inclusion of the WWRC analysis can give additional information when assessing the impact of different management on soil hydraulic properties.
Long-term no tillage management impact on soil hydro-physical properties in coffee cultivation
2021, Geoderma
Citation Excerpt :
Moreover, a compacted layer below the tilled soil (plough pan) may develop (Reichert et al., 2009). However, some short-term studies investigating MT and NT have reported an increase in bulk density values, commonly resulting in poor soil structure and restriction of root growth and water movement in the untilled topsoil (Ball and Robertson, 1994; Morris et al., 2010; Munkholm et al., 2013). In contrast, most long-term studies on these managements posited that the soil structure improves over time in MT and NT fields (Ajayi and Horn, 2016; Rodrigues et al., 2016; Miguel et al., 2016; Ajayi et al., 2019; Schlüter et al., 2018; Pöhlitz et al., 2019).
Tillage management in agricultural fields has consequences on the dynamics of the soil structure and soil’s pore functions with far reaching effects on the sustainability of cropping system. The purpose of this study is to investigate changes in both capacity and intensity properties of a very clayey Rhodic Hapludox after 37-year of continuous conventional tillage (CT) and no till (NT) management for weed control under coffee plantations. Undisturbed soil samples were collected at four depths and used for hydro-physical characterization. The tillage treatments modified the capacity and intensity parameters differently depending on the sampled depth. Bulk density was similar at the 0–20 cm layer in both CT and NT treatments, but at the 20–40 cm layer, NT significantly increased the bulk density by (6–8%). Also, NT increased the stability of 8–2 mm macroaggregate fraction in water and significantly increased the geometric mean diameter and the mean weight diameter of the water-stable aggregates in most of the layers relative to CT. Moreover, CT increased hydraulic conductivity by 53% in the surface layer. Generally, the magnitude of the differences in soil properties as a consequence of the 2 tillage treatments was greater for hydraulic conductivity (soil intensity parameters) than the bulk density (soil capacity parameters). In the NT plots, more water was retained within the available water range, while CT presented steeper water retention curves and poorly graded pore-size distributions. The pore-size distribution and hydraulic capacity function curves showed that the impact of CT management was more pronounced at the 10–20 cm layer, while that of NT management was most significant at the 0–10 cm layer (soil surface). This study showed that in addition to soil strength indicators, soil intensity parameters (hydraulic conductivity, hydraulic capacity and soil structure) more succinctly explained differential impact of tillage systems on soils, as compared to the capacity parameters (bulk density, pore size distribution, air capacity and available water capacity).
Importance of short-term temporal variability in soil physical properties for soil water modelling under different tillage practices
2021, Soil and Tillage Research
Soil properties are often assumed to be static over time in hydrological studies, especially in hydrological modelling. Although it is well appreciated that soil structure and its impact on hydraulic properties are time-variable, particularly on cultivated land, very few studies have focused on quantifying the influence of such changes on soil hydrology, especially at the short term (i.e. seasonal). This study explored the value of incorporating such short-term time-variable soil properties in hydrological models. It is based on soil hydraulic properties from temporal field data under no-till done by direct seeding and under conventional cultivation done by ploughing to 0.2 m and harrowing. It uses a controlled tillage experiment in Scotland, on a soil with very good structural stability that experiences gentle rainfall in a temperate oceanic climate (Köppen Cfb). Water retention data were collected from intact soil cores sampled at 0.025, 0.095 and 0.275 m depth at three times between April and August 2013; (i) immediately following tillage, (ii) at barley crop establishment 1 month later and (iii) after harvest. Soil structure varied over time, with no-till soils gaining porosity and ploughed soils losing porosity. We hypothesised that no-till soils would have less seasonal temporal variability, but found it to be comparable to ploughed soils, albeit with pore structure changes following different trends. These changes were reflected in Van Genuchten fitting parameters, which if accounted for in 1-D HYDRUS modelling, had a marked impact on modelled soil water content over time if contrasted to predictions assuming a static pore structure. Using data from multiple sampling events, as opposed to one sampling event, resulted in up to a 44 % difference in soil water content predictions and increased the temporal variability by a factor of 1.5. Hence, our results have demonstrated that it is important to account for short-term temporal variability in soil physical properties in soil water modelling studies, and should not be ignored as a default, particularly on cultivated agricultural soils.
Platy structure development under no-tillage in the northern humid Pampas of Argentina and its impact on runoff
2017, Soil and Tillage Research
Citation Excerpt :
There are specific field observations of a platy soil (P) structure, with thin and flat fragments oriented parallel to the soil surface, occurring in the first centimeters of soil in some experiments under NT in the Pampas region (Bonel et al., 2005; Sasal et al., 2006; Alvarez et al., 2009). Some authors have also reported continuous platy structure in silty soils under NT in other areas (Pagliai et al., 1983; Shipitalo and Protz, 1987; Ball and Robertson, 1994; Boizard et al., 2013). In long-term experiments carried out in Pergamino, in the center of the Pampas, this platy structure restricts the water infiltration rate into the soil profile (Sasal et al., 2006).
The no-tillage system (NT) is widespread in the silty soils of the Argentine Humid Pampas. The aims of this study were i) to characterize the evolution of the structure of the A horizon in the northern Humid Pampas due to conversion to NT, particularly the presence of platy structure and its development through time, by taking advantage of a chronosequence since conversion to NT; and ii) to evaluate how platy structure extension in the A horizon relates to characteristics of the crop sequences and runoff in a long-term experiment. Thus, the structure of the A horizon of 25 Argiudolls with different NT history was analyzed using a visual structure evaluation (VSE) method (“le profil cultural”). Fourteen natural-rainfall erosion plots with 3.5% slope were used to analyze the relationship between the soil structural state, the crop sequence and runoff. The VSE method allowed us to understand the structure type organization of silty soils under NT, highlight the regional extent of a platy structure near the soil surface, and study its evolution and impact on runoff. All the sites analyzed exhibited a horizontal platy structure (2–10 cm thick), mainly developing on the soil surface or right under the granular structure on the soil surface. Under the platy structure, a cΦ structure was observed in all the sites (30–75% of the A horizon). A relationship was found between the number of consecutive years under NT and the proportion of platy structure. This evolution may result from the combination of an initial development of the platy structure and a late development of a cГ structure from the soil surface. The results obtained during the five-year period analyzed allowed us to prove that platy structure alters the drainage pattern, restricts water entry into the soil and favors surface runoff according to its proportion in the profile of A horizon.
A contribution to understanding the origin of platy structure in silty soils under no tillage
2017, Soil and Tillage Research
Citation Excerpt :
In addition, soil management with NT emphasizes the low ability of the soil structure to regenerate naturally because of the absence of freeze-thaw processes and the illite type clay, which has low shrinkage-swelling capacity (Senigagliesi and Ferrari, 1993; Taboada et al., 1998). Many authors have reported the presence of platy (P) soil structure under NT (Alvarez et al., 2014, 2009; Ball and Robertson, 1994; Bonel et al., 2005; Morrás et al., 2004; Shipitalo and Protz, 1987; Soracco et al., 2010). Although some of them attribute the formation of P structure to reconsolidation following thawing of winter-formed ice lenses (Hussein and Adey, 1998; Pardini et al., 1995; Sveistrup et al., 2005; VandenBygaart et al. 1999), this explanation is not applicable to the soil temperatures of the Argentinean Pampas, which are rarely below 0.
In silty soils under no tillage (NT), platy (P) soil structure is widespread and constrains water infiltration. Our objectives were (i) to evaluate how traffic and the presence of crop residues influence P structure development in the field and (ii) to characterize changes in soil structure caused by alternation of wetting and drying (w-d) periods for two topsoil layers of a silty soil and two compaction levels in the laboratory. The five-year field experiment was carried out on a Typic Argiudoll under NT and the structure of the A horizon was analyzed using visual soil evaluation (VSE) both before and five years after two traffic levels were applied to four crop sequences. The laboratory experiment of w-d cycles was carried out with two disturbed layers of a Typic Argiudoll, which was repacked to achieve two different bulk densities, and the columns were subjected to 5, 10, or 15 w-d cycles. In the field experiment, the P structure was clearly identified by VSE and corroborated by shear strength and bulk density measurements. The proportion of P structure increased until about 50% of the A horizon after 5 years, irrespective of the traffic or presence of crop residues at the expense of the Φ structure proportion. In the laboratory, consecutive w-d cycles caused changes in soil volume, cracking of the soil surface, and formation of P structure of variable thickness up to 20 mm, confirming that alternation of w-d periods can cause structural modification of the silty soil, in particular horizontally oriented cracks. The number of w-d cycles increased the thickness of the P structure in the upper layer (R² = 0.55) and in the compacted treatment (R² = 0.81). The results obtained constitute important progress in the understanding of the evolution of P structure of silty soils under NT.
Developments in the “profil cultural” method for an improved assessment of soil structure under no-till
2017, Soil and Tillage Research
Citation Excerpt :
This facies, called platy soil structure, has often been described in NT systems in the first ten centimetres of the topsoil in the Pampas region of Argentina (Sasal et al., 2006; Alvarez and Steinbach, 2009). Other authors have also reported the same facies in silty topsoils under NT in other areas (Pagliai et al., 1983; Ball and Robertson, 1994). In France, Boizard et al. (2013) revealed the development of a platy soil structure on top of compacted volumes in RT, which becomes deeper over time.
In France, agronomists have studied the effects of cropping systems on soil structure using a field method that is based on a visual description of the soil structure. This “profil cultural” method was designed as a field diagnostic tool to identify the effects of tillage and compaction on soil structure dynamics. It is of great benefit to agronomists seeking to improve crop management and preserve soil structure and fertility.
However, the “profil cultural” method was developed and has mainly been used in conventional tillage systems with regular ploughing. As there has been an increase in the use of various forms of reduced, minimum and no-tillage systems in many parts of the world, it is necessary to re-evaluate this method’s ability to describe and interpret soil structure dynamics in no-till or reduced tillage. In these situations, changes in soil structure over time are mainly driven by compaction and by regeneration through natural agents (climatic conditions, root growth and macrofauna), therefore it is important to evaluate the effects of these natural processes on soil structure dynamics.
These concerns have led to adaptations and amendments to the initial method based on field observations and experimental work in different cropping systems, soil types and climatic conditions. The description of crack types has been improved and a criterion of biological activity based on the visual examination of clods has been introduced.
To test this modified method, a comparison with the initial method was undertaken and its ability to make diagnoses tested in five experiments in France, Brazil and Argentina. The adapted method allowed an improved assessment of the impact of cropping systems on soil functioning when natural processes were integrated into the description.

View all citing articles on Scopus

View full text

Effects of soil water hysteresis and the direction of sampling on aeration and pore function in relation to soil compaction and tillage

Abstract

J. Agric. Eng. Res.

Soil Tillage Res.

Soil Tillage Res.

Soil Tillage Res.

Soil Tillage Res.

Soil Tillage Res.

Soil Tillage Res.

A functional model of soil porosity based on measurements of gas diffusion

Eur. J. Soil Sci.

A laboratory method to measure gas diffusion and flow in soil and other porous materials

J. Soil Sci.

Gas diffusion, fluid flow and derived pore continuity indices in relation to vehicle traffic and tillage

J. Soil Sci.