An evaluation of the intrinsic sorptivity water repellency index on a range of New Zealand soils

Soil Research ◽  
1991 ◽  
Vol 29 (3) ◽  
pp. 353 ◽  
Author(s):  
MG Wallis ◽  
DR Scotter ◽  
DJ Horne
Keyword(s):  
New Zealand ◽  
Water Drop ◽  
Water Repellency ◽  
Water Infiltration ◽  
Water Repellent ◽  
Ethanol Droplet ◽  
Wide Range ◽  
Order Of Magnitude ◽  
Moisture Conditions ◽  
Short Time

Undisturbed cores were removed from the surface of 14 New Zealand soils with a wide range of textures. The sorptivity to ethanol and water was measured with a 'sorptivity tube' to determine the repellency index (Rl) of each soil. Texture and gravimetric water content were measured, and the water drop penetration time (WDPT) and molarity of ethanol droplet (MED) tests for water repellency were conducted on the soils. The RI measured all soils water repellent (RI> 1.95) at field moisture conditions, and was more sensitive than the WDPT or MED tests. The RI was used to demonstrate that water repellency reduced short-time water infiltration of all soils by approximately an order of magnitude. Actual and 'potential' infiltration was then compared with rainfall and irrigation intensities. This illustrated the hydrological significance of the phenomenon, even in soils which appeared to wet normally (low WDPT). In all soils the curves of cumulative infiltration versus the square root of time for both water and ethanol stayed linear long enough for sorptivity evaluation. However, at longer times the slope of the curve tended to increase for water sorption in the more repellent soils, but decreased consistently for ethanol.

scholarly journals Water repellency of clay, sand and organic soils in Finland

2008 ◽  
Vol 16 (3) ◽  
pp. 267 ◽  
Author(s):  
K. RASA ◽  
R. HORN ◽  
M. RÄTY
Keyword(s):  
Preferential Flow ◽  
Management Practice ◽  
Soil Surface ◽  
Water Repellency ◽  
Organic Soil ◽  
Water Infiltration ◽  
Organic Soils ◽  
Water Repellent ◽  
Moisture Regime ◽  
Wetting Process

Water repellency (WR) delays soil wetting process, increases preferential flow and may give rise to surface runoff and consequent erosion. WR is commonly recognized in the soils of warm and temperate climates. To explore the occurrence of WR in soils in Finland, soil R index was studied on 12 sites of different soil types. The effects of soil management practice, vegetation age, soil moisture and drying temperature on WR were studied by a mini-infiltrometer with samples from depths of 0-5 and 5-10 cm. All studied sites exhibited WR (R index >1.95) at the time of sampling. WR increased as follows: sand (R = 1.8-5.0) < clay (R = 2.4-10.3) < organic (R = 7.9-undefined). At clay and sand, WR was generally higher at the soil surface and at the older sites (14 yr.), where organic matter is accumulated. Below 41 vol. % water content these mineral soils were water repellent whereas organic soil exhibited WR even at saturation. These results show that soil WR also reduces water infiltration at the prevalent field moisture regime in the soils of boreal climate. The ageing of vegetation increases WR and on the other hand, cultivation reduces or hinders the development of WR.;

scholarly journals Variability of water repellency in sandy forest soils under broadleaves and conifers in north-western Jutland/Denmark

2008 ◽  
Vol 3 (Special Issue No. 1) ◽  
pp. S155-S164 ◽  
Author(s):  
N.A Wahl
Keyword(s):  
Soil Water ◽  
Preferential Flow ◽  
Water Drop ◽  
Water Repellency ◽  
Climatic Conditions ◽  
Tree Age ◽  
Critical Surface ◽  
Soil Water Repellency ◽  
Wide Range ◽  
North Western

Soil water repellency has important consequences for ecological and hydrological properties of soils and usually retards infiltration capacity and induces preferential flow. This phenomenon has been known to occur on a wide range of sites under a variety of climatic conditions. The objective of this study was to investigate and characterize soil water repellency on forest sites with identical substrate and climatic conditions, differing in tree age and species. In the Vester Torup Klitplantage, an area comprising a conifer dominated forest plantation stocking on sandy deposits in a coastal setting near the Jammer Bay in north-western Jutland/Denmark, four different forest plots were investigated for water repellency effects four times in 2005. To measure soil water repellency, the water drop penetration time test and the critical surface tension test were carried out. Both tests revealed a seasonal variability in water repellency, exhibiting the highest water repellency for the upper 10 cm of the soil during the summer months, whereas the variability between the different plots seems to be less significant. There was no coherence between humus forms, thickness of litter layer and water repellency.

scholarly journals Oil and grease in soils irrigated with greywater and the potential effect on soil water repellency

2007 ◽  
pp. 479-488
Author(s):  
Michael Travis ◽  
Noam Weisbrod ◽  
Amit Gross
Keyword(s):  
Soil Profile ◽  
Water Movement ◽  
Water Drop ◽  
Capillary Rise ◽  
Management Strategies ◽  
Water Repellency ◽  
Potential Effect ◽  
Oil And Grease ◽  
Ongoing Research ◽  
Order Of Magnitude

The reuse of greywater and other wastewaters are important considerations for effectivewater management strategies. It is also imperative that the potential for detrimentalenvironmental effects be investigated. As part of ongoing research into the reuse ofgreywater and oil-rich agro-wastewaters, the potential impact of oil and grease (O&G)to soils irrigated with greywater (GW) was studied. Greywater streams were sampledand analyzed for O&G content. Along with the greywater, soil profile samples werecollected from garden soils irrigated with these waters. The goal was to determine theO&G content of these GW streams, verify ifeO&G was accumulating in the soil profiles,and investigate the effect O&G can have on water movement through O&Gcontaminated soils.Untreated kitchen GW averaged 200 mg/L O&G, over an order of magnitude more thanother GW streams. GW-irrigated soils showed O&G accumulation of up to 200 mg/kgwithin the first 20-cm of depth. GW with low O&G concentration (<! 0 mg/L) stilldemonstrated long-tenn accumulation in the soil profile, with O&G concentration of150 mg/kg. To detennine the potential effects that O&G accumulation may have onwater movement in soil, capillary rise and water drop penetration time (WDPT)experiments were conducted. The results showed up to 60% decrease in capillary rise insand containing 250 mg/kg O&G. Interestingly, no additional reduction in capillary risewas observed at concentrations above 250 mg/kg. WDPT was observed to increaselinearly (from nearly instantaneous to over 2 seconds) with increased O&G content, upto 1000 mg/kg. This work demonstrated that O&G in GW used for irrigation canaccumulate in soil and may lead to a significant water repellency and reduction in thesoils ability to transmit water.

scholarly journals Soil hydrophobicity: comparative study of usual determination methods

2015 ◽  
Vol 45 (2) ◽  
pp. 260-266 ◽  
Author(s):  
Eduardo Saldanha Vogelmann ◽  
José Miguel Reichert ◽  
Juliana Prevedello ◽  
Gabriel Oladele Awe ◽  
Dalvan José Reinert
Keyword(s):  
Water Drop ◽  
Soil Layer ◽  
Organic Matter Content ◽  
Soil Samples ◽  
Water Infiltration ◽  
Water Repellent ◽  
Hydrophobicity Index ◽  
Coefficients Of Variation ◽  
Soil Hydrophobicity ◽  
Penetration Time

Hydrophobic or water repellent soils slowly absorb water because of the low wett ability of the soil particles which are coated with hydrophobic organic substances. These pose significant effects on plant growth, water infiltration and retention, surface runoff and erosion. The objective of this study was to compare the performance of tension micro-infiltrometer(TMI) and the water drop penetration time (WDPT) methods in the determination of the hydrophobicity index of eighteen soils from southern Brazil. Soil samples were collected from the 0-5cm soil layer to determine particle size distribution, organic matter content, hydrophobicity index of soil aggregates and droplet penetration time of disaggregated and sieved soil samples. For the TMI method the soil samples were subjected to minor changes due to the use of macroaggregates to preserve the distribution of solid constituents in the soil. Due to the homogeneity of the soil samples the WDPT method gave smaller coefficients of variation unlike the TMI method where the soil structure is preserved. However, both methods had low coefficients of variation, and are thus effective for determining the soil hydrophobicity, especially when the log hydrophobicity index or log WDPT is >1.

Managing soils to enhance the potential for bioremediation of water repellency

Soil Research ◽  
2005 ◽  
Vol 43 (7) ◽  
pp. 803 ◽  
Author(s):  
Margaret M. Roper
Keyword(s):  
Management Practices ◽  
Crop Yields ◽  
Water Repellency ◽  
Water Infiltration ◽  
Most Probable Number ◽  
Water Repellent ◽  
Gradual Decline ◽  
Kaolinite Clay ◽  
Probable Number ◽  
Degrading Bacteria

Water repellency can significantly reduce crop and pasture establishment and production in sandy soils. Management practices that increase the rate of water infiltration into dry soils following the first rains at the end of the dry season were investigated. In the laboratory, addition of water to water repellent soil and maintenance of warm moist conditions produced a gradual decline in water repellency. This was supported by results in the field which showed that under daily irrigation there was a gradual decline in water repellency over time. However, under dryland conditions, other mechanisms to increase water infiltration had to be found. In the laboratory, after the addition of lime and kaolinite clay, there was an initial rapid decline in repellency, indicative of a physical mechanism, followed by a more gradual decline suggesting a biological response. In the field, under dryland conditions, the addition of lime and kaolinite clay resulted in a reduction in water repellency, and in the case of lime, this effect increased with the size of application. Estimates of the numbers of wax-degrading bacteria in the treated soils, using a most-probable-number assay, showed at least a 10-fold increase in lime-treated sands, but not in the clay-treated sands. The results suggest that lime may provide a viable alternative for increasing the wettability of soils by physical mechanisms and by promoting microbial activity by bacteria responsible for wax degradation, resulting in more consistent plant germination and establishment, and increased crop yields.

Impact of crop residue retention and tillage on water infiltration into a water-repellent soil

Biologia ◽  
2015 ◽  
Vol 70 (11) ◽  
Author(s):  
Philip R. Ward ◽  
Margaret M. Roper ◽  
Ramona Jongepier ◽  
Shayne F. Micin
Keyword(s):  
Crop Residue ◽  
Water Repellency ◽  
Water Infiltration ◽  
Soil Tillage ◽  
Water Repellent ◽  
Residue Removal ◽  
Growing Seasons ◽  
Water Repellence ◽  
The Impact ◽  
Residue Retention

AbstractWater repellence is a condition in which soils become hydrophobic and do not readily absorb water. The condition causes problems in agricultural production relating to water availability for seed germination and plant growth. In this research we assess the impact of disturbing the soil by a single annual soil tillage (compared with no-till) and crop residue retention (compared with residue removal by burning) on the severity of water repellency, and on water infiltration during and immediately after rainfall, for 5 discrete rainfall events over an 18-month period covering two crop growing seasons. Soil tillage and crop residue removal were associated with decreased severity of water repellency. Despite this, soil tillage resulted in less infiltration of rain water, especially in the crop inter-row spaces, one hour after the commencement of rainfall, and 6 hours after the conclusion of rainfall. Where a single soil tillage was performed, soil in the inter-row spaces absorbed 19-30% of incident rainfall, compared with 58-78% in undisturbed soils. This was observed for a rainfall event 11 months after soil tillage, indicating that soil tillage has a long-lasting impact on pathways of water entry into the soil.

The isolation and characterisation of bacteria with the potential to degrade waxes that cause water repellency in sandy soils

Soil Research ◽  
2004 ◽  
Vol 42 (4) ◽  
pp. 427 ◽  
Author(s):  
Margaret M. Roper
Keyword(s):  
Agricultural Production ◽  
Complex Mixture ◽  
Sandy Soils ◽  
Water Repellency ◽  
Water Repellent ◽  
Bacterial Isolates ◽  
Hydrophobic Compounds ◽  
Degrading Bacteria ◽  
Wide Range ◽  
Fatty Acids And Alcohols

Water repellency in soils is caused by waxy coatings on particles and can seriously limit agricultural production. Bioremediation of these soils, using wax-degrading bacteria isolated from soils and other sources rich in microorganisms, was investigated. Wool wax, a complex mixture of fatty acids and alcohols, was used to select bacteria capable of metabolising hydrophobic compounds. Of the 37 stable isolates, two-thirds were actinomycetes. These organisms are known for their ability to metabolise a wide range of organic compounds. Degradation of waxes associated with soil particles is facilitated by the production of biosurfactants that emulsify hydrophobic compounds. Measurement of biosurfactant production indicated that those isolates that grew best on hydrocarbon were also the most prolific biosurfactant producers. Inoculation of water-repellent soils, under controlled conditions, with the most efficient wax-degrading bacterial isolates resulted in significant improvements in soil wettability.

A quick fix for modeling infiltration in water-repellent soils

2021 ◽  
Author(s):  
Ryan Stewart ◽  
Majdi R. Abou Najm ◽  
Simone Di Prima ◽  
Laurent Lassabatere
Keyword(s):  
Soil Water ◽  
Wide Spectrum ◽  
Correction Term ◽  
Water Repellency ◽  
Infiltration Rate ◽  
Water Repellent ◽  
Soil Water Repellency ◽  
Simple Method ◽  
Wide Range ◽  
Infiltration Models

&lt;p&gt;Water repellency occurs in soils under a wide spectrum of conditions. Soil water repellency can originate from the deposition of resinous materials and exudates from vegetation, vaporization and condensation of organic compounds during fires, or the presence of anthropogenic-derived chemicals like petroleum products, wastewater or other urban contaminants. Its effects on soils range from mild to severe, and it often leads to hydrophobic conditions that can significantly impact the infiltration response with effects extending to the watershed-scale. Those effects are often time-dependent, making it a challenge to simulate infiltration behaviors of water-repellent soils using standard infiltration models. Here, we introduce a single rate-constant parameter (&amp;#945;&lt;sub&gt;WR&lt;/sub&gt;) and propose a simple correction term (1-e&lt;sup&gt;-&amp;#945;WRt&lt;/sup&gt;) to modify models for infiltration rate. This term starts with a value of zero at the beginning of the infiltration experiment (t = 0) and asymptotically approaches 1 as time increases, thus simulating a decreasing effect of soil water repellency through time. The correction term can be added to any infiltration model (one- two- or three-dimensional) and will account for the water repellency effect. Results from 165 infiltration experiments from different ecosystems and wide range of water repellency effects validated the effectiveness of this simple method to characterize water repellency in infiltration models. Tested with the simple two-term infiltration equation developed by Philip, we obtained consistent and substantial error reductions, particularly for more repellent soils. Furthermore, results revealed that soils that were burned during a wildfire had smaller &amp;#945;&lt;sub&gt;WR&lt;/sub&gt;&amp;#160;values compared to unburned controls, thus indicating that the magnitude of &amp;#945;&lt;sub&gt;WR&lt;/sub&gt;&amp;#160;may have a physical basis.&lt;/p&gt;

Water Repellency Control of Oxygen-Free Copper Surface by Diamond-Cut Micro Grooves

2015 ◽  
Vol 9 (4) ◽  
pp. 396-402 ◽  
Author(s):  
Kazuma Asakura ◽  
◽  
Jiwang Yan
Keyword(s):  
Contact Angle ◽  
Flat Surface ◽  
Water Drop ◽  
Water Repellency ◽  
Copper Surface ◽  
Industrial Applications ◽  
Burr Formation ◽  
Wide Range ◽  
Grooved Surface ◽  
Maximum Contact

Improving water repellency of a metal surface is required in a wide range of industrial applications. In this study, the water repellency control of an oxygen-free copper surface was attempted by generating micro V grooves on the surface by using ultraprecision cutting technology. The results showed that the maximum contact angle of a water drop on a micro V-grooved surface could be as high as approximately twice that of a flat surface. The contact angle depended strongly on the direction, depth, pitch of the grooves, and burr formation at the edges of the micro grooves. A method for controlling burr formation was proposed.

scholarly journals Application of minidisk infiltrometer to estimate water repellency in Mediterranean pine forest soils

2017 ◽  
Vol 65 (3) ◽  
pp. 254-263 ◽  
Author(s):  
Vincenzo Alagna ◽  
Massimo Iovino ◽  
Vincenzo Bagarello ◽  
Jorge Mataix-Solera ◽  
Ľubomír Lichner
Keyword(s):  
Water Drop ◽  
Mineral Soil ◽  
Soil Layer ◽  
Water Repellency ◽  
Water Infiltration ◽  
Pine Forests ◽  
Hydrophobic Compounds ◽  
Floor Layer ◽  
Alternative Procedures ◽  
Mediterranean Pine

AbstractAssessment of soil water repellency (SWR) was conducted in the decomposed organic floor layer (duff) and in the mineral soil layer of two Mediterranean pine forests, one in Italy and the other in Spain, by the widely-used water drop penetration time (WDPT) test and alternative indices derived from infiltration experiments carried out by the minidisk infiltrometer (MDI). In particular, the repellency index (RI) was calculated as the adjusted ratio between ethanol and water soil sorptivities whereas the water repellency cessation time (WRCT) and the specifically proposed modified repellency index (RIm) were derived from the hydrophobic and wettable stages of a single water infiltration experiment. Time evolution of SWR and vegetation cover influence was also investigated at the Italian site. All indices unanimously detected severe SWR conditions in the duff of the pine forests. The mineral subsoils in the two forests showed different wettability and the clay-loam subsoil at Ciavolo forest was hydrophobic even if characterized by organic matter (OM) content similar to the wettable soil of an adjacent glade. It was therefore assumed that the composition rather than the total amount of OM influenced SWR. The hydraulic conductivity of the duff differed by a factor of 3.8–5.8 between the two forested sites thus influencing the vertical extent of SWR. Indeed, the mineral subsoil of Javea showed wettable or weak hydrophobic conditions probably because leaching of hydrophobic compounds was slowed or prevented at all. Estimations of SWR according to the different indices were in general agreement even if some discrepancies were observed. In particular, at low hydrophobicity levels the SWR indices gathered from the MDI tests were able to signal sub-critical SWR conditions that were not detected by the traditional WDPT index. The WRCT and modified repellency index RImyielded SWR estimates in reasonable agreement with those obtained with the more cumbersome RI test and, therefore, can be proposed as alternative procedures for SWR assessment.

Sign in / Sign up

Export Citation Format

Share Document