Influence of active aluminium oxides on water movement in soils

Soil Research ◽  
1969 ◽  
Vol 7 (3) ◽  
pp. 325 ◽  
Author(s):  
CK Tweneboah ◽  
JW Kijne ◽  
DJ Greenland
Keyword(s):  
Sodium Chloride ◽  
Soil Water ◽  
Water Retention ◽  
Water Movement ◽  
Soil Water Retention ◽  
Water Diffusivity ◽  
The Stability ◽  
Soil Pores ◽  
Water Contents ◽  
Soil Water Contents

Active aluminium oxides were removed from several soils by treatment with 0.5M calcium chloride or lM sodium chloride at pH 1.5. Soil-water retention and soil-water diffusivity were determined and contrasted with the values for these properties obtained after treatment with neutral salts. The changes resulting from the removal of aluminium oxides were relatively small in calcium saturated systems, but in sodium saturated systems soil-water diffusivity was drastically reduced by the prior removal of aluminium oxides. The results are discussed in terms of the influence of aluminium oxides on the stability of soil pores at different soil-water contents.

scholarly journals Effect of Nano-Carbon on Water Holding Capacity in a Sandy Soil of the Loess Plateau

2017 ◽  
Vol 21 (4) ◽  
pp. 189-195 ◽  
Author(s):  
Beibei Zhou ◽  
Xiaopeng Chen
Keyword(s):  
Water Content ◽  
Soil Water ◽  
Loess Plateau ◽  
Sandy Soil ◽  
Water Retention ◽  
Soil Mixture ◽  
Cumulative Infiltration ◽  
Nano Carbon ◽  
Water Contents ◽  
Soil Water Contents

The poor water retention capacity of sandy soils commonly aggregate soil erosion and ecological environment on the Chinese Loess Plateau. Due to its strong capacity for absorption and large specific surface area, the use of nanocarbon made of coconut shell as a soil amendment that could improve water retention was investigated. Soil column experiments were conducted in which a layer of nanocarbon mixed well with the soil was formed at a depth of 20 cm below the soil surface. Four different nanocarbon contents by weight (0%, 0.1%, 0.5%, and 1%) and five thicknesses of the nanocarbon- soil mixture layer ranging from 1 to 5 cm were considered. Cumulative infiltration and soil water content distributions were determined when water was added to soil columns. Soil Water Characteristic Curves (SWCC) were obtained using the centrifuge method. The principal results showed that the infiltration rate and cumulative infiltration increased with the increases of nanocarbon contents, to the thicknesses of the nano carbon-soil mixture layer. Soil water contents that below the soil-nano carbon layer decreased sharply. Both the Brooks-Corey and van Genuchten models could describe well the SWCC of the disturbed sandy soil with various nano carbon contents. Both the saturated water content (θs), residual water content (θr) and empirical parameter (α) increased with increasing nano carbon content, while the pore-size distribution parameter (n) decreased. The available soil water contents were efficiently increased with the increase in nanocarbon contents.

scholarly journals Pedotransfer functions related to spatial variability of water retention attributes for lowland soils

2010 ◽  
Vol 34 (3) ◽  
pp. 669-680 ◽  
Author(s):  
Álvaro Luiz Carvalho Nebel ◽  
Luís Carlos Timm ◽  
Wim Cornelis ◽  
Donald Gabriels ◽  
Klaus Reichardt ◽  
...  
Keyword(s):  
Spatial Variability ◽  
Soil Water ◽  
Water Retention ◽  
Pedotransfer Functions ◽  
Predictive Values ◽  
Soil Variables ◽  
Mean And Variance ◽  
Different Characteristics ◽  
Water Contents ◽  
Soil Water Contents

The estimation of non available soil variables through the knowledge of other related measured variables can be achieved through pedotransfer functions (PTF) mainly saving time and reducing cost. Great differences among soils, however, can yield non desirable results when applying this method. This study discusses the application of developed PTFs by several authors using a variety of soils of different characteristics, to evaluate soil water contents of two Brazilian lowland soils. Comparisons are made between PTF evaluated data and field measured data, using statistical and geostatistical tools, like mean error, root mean square error, semivariogram, cross-validation, and regression coefficient. The eight tested PTFs to evaluate gravimetric soil water contents (Ug) at the tensions of 33 kPa and 1,500 kPa presented a tendency to overestimate Ug 33 kPa and underestimate Ug1,500 kPa. The PTFs were ranked according to their performance and also with respect to their potential in describing the structure of the spatial variability of the set of measured values. Although none of the PTFs have changed the distribution pattern of the data, all resulted in mean and variance statistically different from those observed for all measured values. The PTFs that presented the best predictive values of Ug33 kPa and Ug1,500 kPa were not the same that had the best performance to reproduce the structure of spatial variability of these variables.

scholarly journals How Do Newly-Amended Biochar Particles Affect Erodibility and Soil Water Movement?—A Small-Scale Experimental Approach

Soil Systems ◽  
2020 ◽  
Vol 4 (4) ◽  
pp. 60 ◽  
Author(s):  
Steffen Seitz ◽  
Sandra Teuber ◽  
Christian Geißler ◽  
Philipp Goebes ◽  
Thomas Scholten
Keyword(s):  
Hydraulic Conductivity ◽  
Soil Erosion ◽  
Soil Water ◽  
Water Retention ◽  
Water Movement ◽  
Early Stage ◽  
Substrate Surface ◽  
Small Scale ◽  
Soil Water Retention ◽  
Biochar Amendment

Biochar amendment changes chemical and physical properties of soils and influences soil biota. It is, thus, assumed that it can also affect soil erosion and erosion-related processes. In this study, we investigated how biochar particles instantly change erodibility by rain splash and the initial movement of soil water in a small-scale experiment. Hydrothermal carbonization (HTC)-char and Pyrochar were admixed to two soil substrates. Soil erodibility was determined with Tübingen splash cups under simulated rainfall, soil hydraulic conductivity was calculated from texture and bulk soil density, and soil water retention was measured using the negative and the excess pressure methods. Results showed that the addition of biochar significantly reduced initial soil erosion in coarse sand and silt loam immediately after biochar application. Furthermore, biochar particles were not preferentially removed from the substrate surface, but increasing biochar particle sizes partly showed decreasing erodibility of substrates. Moreover, biochar amendment led to improved hydraulic conductivity and soil water retention, regarding soil erosion control. In conclusion, this study provided evidence that biochar amendments reduce soil degradation by water erosion. Furthermore, this effect is detectable in a very early stage, and without long-term incorporation of biochar into soils.

A COMPARISON OF MEASURED AND MODELLED SOIL WATER RETENTION DATA

1987 ◽  
Vol 67 (3) ◽  
pp. 697-703 ◽  
Author(s):  
R. DE JONG ◽  
J. A. MCKEAGUE
Keyword(s):  
Organic Carbon ◽  
Soil Water ◽  
Water Retention ◽  
Organic Carbon Content ◽  
Retention Data ◽  
Soil Water Retention ◽  
Extreme Caution ◽  
High Potentials ◽  
Measured Water ◽  
Water Contents

Soil water retention data, predicted from texture, organic carbon content and bulk densities, were compared to measured values. Although significant correlations were obtained, the differences between predicted and measured water contents were large, especially at high potentials, and suggest that extreme caution must be exercised in employing the models under conditions other than those for which they were developed. Key words: Soil water retention, modelling, texture

EFFECTS OF THREE SOIL CONDITIONERS ON WATER CONTENTS IN TWO SOILS AT THREE PRESSURE-PLATE MATRIC POTENTIALS

1987 ◽  
Vol 67 (2) ◽  
pp. 395-397 ◽  
Author(s):  
D. S. STEVENSON
Keyword(s):  
Soil Water ◽  
Water Retention ◽  
Sandy Loam ◽  
Control Treatment ◽  
Silt Loam ◽  
Soil Water Retention ◽  
Pressure Plate ◽  
Loam Soil ◽  
Soil Conditioners ◽  
Water Contents

Soil water contents of a sandy loam and a silt loam soil were measured at −1500, −100, and either −20 or −30 kPa (the finer texture at −30 kPa) on pressure plate equipment, after samples of each soil had been treated with one of three soil conditioners or with water as a control treatment. One of the soil conditioners increased the soil water retention of both soils at all matric potentials while the other two increased soil water retention at −1500 kPa in the silt loam. The implications in terms of water availability to plants are discussed briefly. Key words: Matric potentials, soil water retention, soil conditioners, laboratory

Analysis of spatial variability of soil water retention using the cumulative distribution function matching

2020 ◽  
pp. 1-7
Author(s):  
Nizami Gummatov ◽  
Yakov A. Pachepsky
Keyword(s):  
Spatial Variability ◽  
Soil Water ◽  
Water Retention ◽  
Distribution Functions ◽  
Cumulative Distribution ◽  
Cumulative Probability ◽  
Soil Matric Potential ◽  
Soil Water Retention ◽  
Matric Potential ◽  
Water Contents

The importance of modeling dependencies of spatial variability of soil water content on soil matric potential grows due to the proliferation of ensemble modeling, data assimilations, and other soil water modeling applications. The objective of this work was to investigate conversions between cumulative distribution functions of water contents at different matric potentials. In total, 80 samples were taken in the nodes of the grid to measure soil water retention using sand and sand–kaolin capillarimeters at absolute values of soil matric potential of 0.001, 0.003, 0.010, 0.020, and 0.050 MPa, and with the water vapor desorption method at 3, 21, 39, 82, and 142 MPa. The probabilities of distributions of both non-transformed and log-transformed soil water contents being normal appeared to be larger than 0.05 in most cases. Using the probit function to represent the observed variability allowed us to match cumulative probability distributions at different soil water potentials. Slopes of dependencies of probits on non-transformed and log-transformed water contents had one-parametric linear dependencies on the logarithms of the absolute value of soil matric potential in capillary and adsorptive potential ranges.

A review of fractal, prefractal and pore-solid-fractal models for parameterizing the soil water retention curve

2011 ◽  
Vol 91 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Behzad Ghanbarian-Alavijeh ◽  
Humberto Millán ◽  
Guanhua Huang
Keyword(s):  
Soil Water ◽  
Water Retention ◽  
Physical Models ◽  
Water Retention Curve ◽  
Retention Data ◽  
Soil Water Retention Curve ◽  
Soil Water Retention ◽  
Retention Curve ◽  
Fractal Models ◽  
Water Contents

Ghanbarian-Alavijeh, B., Millán, H. and Huang, G. 2011. A review of fractal, prefractal and pore-solid-fractal models for parameterizing the soil water retention curve. Can. J. Soil Sci. 91: 1–14. The soil water retention curve is an important hydraulic parameter for characterizing water flow and contaminant transport in porous media. Therefore, many empirical, semi physical, and physical models of the soil water retention curve have been proposed. Among them, fractal models appear to be a useful approach for modeling soil as a heterogeneous porous medium and its hydraulic characteristics. Fractal models are mathematically based, and their parameters have physical meanings. In this study, we review published fractal, prefractal and pore-solid-fractal models for soil water retention curves including Tyler and Wheatcraft, Rieu and Sposito, Perrier et al., Perfect, Bird et al., Millán and González-Posada, and Cihan et al. models. In the pore-solid fractal (PSF) approach the pore phase and matrix phase have a finite volume even for an infinite number of iterations. The results of fitting the PSF model to measured soil water retention data indicate that this model works well, particularly at lower water contents.

Sign in / Sign up

Export Citation Format

Share Document