Evaluation of the effects of cation combinations on soil hydraulic conductivity
N. S. Jayawardane A C , E. W. Christen A B , M. Arienzo A and W. C. Quayle AA CSIRO Land and Water, PMB 3, Hanwood, Griffith, NSW 2680, Australia.
B University of New England, Armidale, NSW 2350, Australia.
C Corresponding author. Email: jayn7777@hotmail.com
Soil Research 49(1) 56-64 https://doi.org/10.1071/SR09222
Submitted: 6 March 2009 Accepted: 29 July 2010 Published: 4 February 2011
Abstract
Effects of soil solution cation concentrations and ratios on hydraulic properties must be understood in order to model soil water flow in reactive soils or develop guidelines for sustainable land application of wastewater. We examined effects of different ratios and concentrations of the cations Ca2+, Mg2+, Na+, and K+, using hydraulic conductivity measurements in repacked soil cores, as an indicator of soil structural stability. We examined widely used indices—sodium, potassium, and monovalent cation absorption ratios (SAR, PAR, MCAR)—which assume that the flocculating effects of Ca2+ and Mg2+ are the same, and the dispersive effects of Na+ and K+ are the same. Our laboratory measurements indicate that at any given values of MCAR, the reductions in soil hydraulic conductivity with decrease in electrolyte concentration are not identical for different cation combinations in solution. The hydraulic conductivity curves showed a marked lateral shifting for both the surface and subsurface soils from a winery wastewater application site. This indicates that MCAR is inadequate as a soil stability parameter in soil solutions containing a mixture of Na+, K+, Ca2+, and Mg2+.
We employed an unpublished equation that was proposed by P. Rengasamy as a modified index of soil stability for mixed cation combinations, using calculated relative flocculating powers of different cations (‘CROSS’, cation ratio of structural stability). Our observation of lateral shift in hydraulic conductivity measurements at any value of MCAR appears to relate to changes in CROSS values for all cation combinations tested, except for K–Mg solutions, for which a more generalised CROSS equation with modified parameters seems more suitable for calculating the CROSS value. Appropriate modified parameters for use in this generalised CROSS equation were determined empirically, using the experimental data.
We derived a combination of threshold electrolyte concentration and CROSS values required to maintain high hydraulic conductivity for the soils at a winery wastewater application site. The potential use of this relationship in developing management practices for sustainable wastewater management at the site is discussed. Further research on the applicability of CROSS and generalised CROSS equations for other soils in the presence of different mixed cation combinations is needed.
Additional keywords: salinity, sodicity, CROSS, MCAR, SAR, PAR, TEC.
References
Isbell RF (1996) ‘The Australian Soil Classification.’ (CSIRO Publishing: Melbourne)Jayawardane NS (1977) The effect of salt composition of groundwaters on the rate of salinisation of soils from a watertable. PhD Thesis, University of Tasmania, Australia.
Jayawardane NS (1979) An equivalent salt solutions method for predicting hydraulic conductivities of soils for different salt solutions. Australian Journal of Soil Research 17, 423–428.
| An equivalent salt solutions method for predicting hydraulic conductivities of soils for different salt solutions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL3cXhs1aksbs%3D&md5=c969f6cf77fd426a03313748fd351c7dCAS |
Jayawardane NS (1983) Further examination of the equivalent salt solution method for predicting hydraulic conductivity of soils for different salt solutions. Australian Journal of Soil Research 21, 105–108.
| Further examination of the equivalent salt solution method for predicting hydraulic conductivity of soils for different salt solutions.Crossref | GoogleScholarGoogle Scholar |
Jayawardane NS (1992) Predicting unsaturated hydraulic conductivity changes of a loamy soil in different salt solutions using the equivalent salt solutions concept. Australian Journal of Soil Research 30, 565–571.
| Predicting unsaturated hydraulic conductivity changes of a loamy soil in different salt solutions using the equivalent salt solutions concept.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK3sXjvVSksA%3D%3D&md5=3ef61910b5445fc39e02293f93e101d5CAS |
Jayawardane NS, Beattie JA (1979) Effect of salt solution composition on moisture release curves of soils. Australian Journal of Soil Research 17, 89–99.
| Effect of salt solution composition on moisture release curves of soils.Crossref | GoogleScholarGoogle Scholar |
Jayawardane NS, Blackwell PS (1991) The relationship between equivalent salt solution series of different soils. Journal of Soil Science 42, 95–102.
| The relationship between equivalent salt solution series of different soils.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK3MXktVOmsrc%3D&md5=384e512332fb3ba7de7b7ae91bb49a3eCAS |
McNeal BL, Coleman NT (1966) Effect of solution composition on soil hydraulic conductivity. Soil Science Society of America Proceedings 30, 308–312.
| Effect of solution composition on soil hydraulic conductivity.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaF28XkvVWisrY%3D&md5=f3324dae2d4aab46d976c81d7d00c4e6CAS |
McNeal BL, Norvell WA, Coleman NT (1966) Effect of solution composition on the swelling of extracted soil clays. Soil Science Society of America Proceedings 30, 313–317.
| Effect of solution composition on the swelling of extracted soil clays.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaF28XkvVWisrk%3D&md5=0c46fe890a36328fede2000c00d7ff4fCAS |
Quirk JP, Schofield RK (1955) The effect of electrolyte concentration on soil permeability. Journal of Soil Science 6, 163–178.
| The effect of electrolyte concentration on soil permeability.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaG28XhslKqug%3D%3D&md5=8831094d4d41d6cd93b61262e52ea781CAS |
Rengasamy P (2002) Clay dispersion. In ‘Soil physical measurement and interpretation for land evaluation’. (Eds N McKenzie, K Coughlan, H Cresswell) pp. 200–210. (CSIRO Publishing: Melbourne)
Rengasamy P, Greene RSB, Ford GW, Mehanni AH (1984) Identification of dispersive behaviour and management of Red-brown earths. Australian Journal of Soil Research 22, 413–431.
| Identification of dispersive behaviour and management of Red-brown earths.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2MXitlCrtA%3D%3D&md5=0c66e8b67c4cff60c13b0f90092dddb9CAS |
Rengasamy P, Sumner ME (1998) Processes involved in sodic behaviour. In ‘Sodic soils: distribution, processes, management and environmental consequences’. (Eds ME Sumner, R Naidu) (Oxford University Press: New York)
Richards LA (Ed.) (1954) ‘Diagnosis and improvement of saline and alkali soils.’ Agricultural Handbook No. 60. (USDA: Washington, DC)
Smiles DE, Smith CJ (2004) A survey of cation content of piggery effluent and some consequences of its use to irrigate soils. Australian Journal of Soil Research 42, 231–246.
| A survey of cation content of piggery effluent and some consequences of its use to irrigate soils.Crossref | GoogleScholarGoogle Scholar |
Smiles DE, Smith CJ (2008) Absorption of gypsum solution by a potassic soil: a data set. Australian Journal of Soil Research 46, 67–75.
| Absorption of gypsum solution by a potassic soil: a data set.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXhs1Wmsb8%3D&md5=e811d533520fbea73739f28d16bf173eCAS |
