C S I R O L A N D a n d W AT E R

Physical Properties of Soils in the Murrumbidgee and Coleambally Irrigation Areas J. Hornbuckle and E. Christen

CSIRO Land and Water, Griffith NSW 2680 Technical Report 17/99 June 1999

PHYSICAL PROPERTIES OF SOILS IN THE MURRUMBIDGEE AND COLEAMBALLY IRRIGATION AREAS

J. Hornbuckle and E. Christen

CSIRO Land and Water PMB 3 GRIFFITH NSW 2680 (02) 69 601500

Citation Details: Hornbuckle, J. and Christen, E.(1999). Physical properties of soils in the Murrumbidgee and Coleambally Irrigation Areas. CSIRO Land and WaterTechnical Report 17/99.

Copies of this report available from: Publications or Information CSIRO Land and Water GPO Box 1666 CANBERRA ACT 2601

II

SUMMARY

There are over 90 different soil types mapped in the Murrumbidgee Irrigation Area (MIA) and the Coleambally Irrigation Area (CIA). These soils have different properties that are important for the design and establishment of irrigation and farming systems and also for managing and sustaining existing farming systems.

In the past 30 years there have been over 80 studies into the physical properties of these soils, which are important to manage and utilise the soils to their full extent. The results of these studies have been documented in published and unpublished forms, which have been difficult to access easily and quickly, so there was a need to bring all this information together into a single document. The data from these studies has been compiled in this report that should prove useful to farmers, farming advisors, engineers and researchers with an interest in the soils of the region.

The soil properties, which were included in the review, were chosen by discussion with likely users of the review: e.g., surveyors, resource mangers, farming advisors and researchers. The soil properties that were included are: bulk density, texture (particle size analysis ), porosity, infiltration, hydraulic conductivity, plant available water, soil moisture characteristic, electrical conductivity (salinity), and exchangeable sodium percent (sodicity). The properties chosen are most important for irrigated agriculture in terms of water movement and retention.

The report breaks down the large number of individual soil types that occur in the MIA and CIA into five broad soil groups that are:

1. Clays, which were further divided into self mulching and hard setting clays 2. Red-brown earths, which were further divided into four subplasticity classes 3. Transitional red brown earths 4. Sands over clay (solodized solonetz) 5. Deep sandy soils

III

The soils that occur in each group are listed in the report. Data relating the soils in each group have been listed and statistical information provided on the data for each soil group. The information has also been presented in tables and graphs to show the change in the soil property with depth. Having gathered and analysed all the data for a particular soil group, a typical set of values for each soil property was established. In some cases there was very little or no data for a particular soil property and thus a typical value could not be determined. These typical values are intended to give readers an indication of the values that might be expected for soils in that group. These values are not statistically derived but are the authors’ interpretation of all the data available.

The report also contains two CSIRO reports documenting studies on soil properties in the CIA and MIA led by John Loveday in 1966 and 1978. The reports contain valuable soil property information that was used in the review and also data on other soil properties that were not included the review. A soil property reference list is also included, as an appendix, showing the soil property information that was contained in the 78 papers reviewed.

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ACKNOWLEDGMENTS

Funding of a CSIRO summer studentship that enabled John Hornbuckle to undertake this work by Mr A. van der Lely, Department of Land and Water Conservation, Leeton, and Mr A. Parle of Parle Foods Pty. Ltd., Griffith, is gratefully acknowledged

We would also like to thank Mr. Geoff Beecher, NSW Agriculture, Leeton, for his assistance in providing his bibliography of soils of the Riverina and Dr Warren Muirhead for his assistance in grouping of soils.

We also would like to thank D. Smith, S. Prathapar and P. Charlesworth of CSIRO Land and Water, Griffith for providing us with soils data.

We gratefully acknowledge the assistance of D. Skehan in editing this document.

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TABLE OF CONTENTS 1

INTRODUCTION ........................................................................................................................ 1

2

OBJECTIVES............................................................................................................................... 3

3

METHODOLOGY ....................................................................................................................... 3 3.1

4

3.1.1

Data collection and selection........................................................................................... 6

3.1.2

Geomorphology of the Area ............................................................................................. 7

3.1.3

Description and classification of the soils ....................................................................... 8

3.2

SOIL TYPES SORTED INTO SOIL GROUPS .................................................................................... 16

3.3

DATA ANALYSIS ....................................................................................................................... 21

3.3.1

Particle size analysis...................................................................................................... 21

3.3.2

Bulk density and porosity ............................................................................................... 21

3.3.3

Infiltration ...................................................................................................................... 22

3.3.4

Hydraulic conductivity ................................................................................................... 22

3.3.5

Moisture characteristics................................................................................................. 22

3.3.6

Electrical conductivities................................................................................................. 23

3.3.7

Exchangeable sodium percentage.................................................................................. 23

SELF MULCHING CLAYS...................................................................................................... 24 4.1

5

6

7

IDENTIFICATION OF IMPORTANT SOIL PROPERTIES ...................................................................... 3

PHYSICAL COMPOSITION .......................................................................................................... 24

4.1.2

Water Movement ............................................................................................................ 32

4.1.3

Water Retention / Moisture Characteristic .................................................................... 35

4.1.4

Soil Salinity/Sodicity ...................................................................................................... 41

HARD SETTING CLAYS ......................................................................................................... 45 5.1.1

Physical Composition..................................................................................................... 45

5.1.2

Water Movement ............................................................................................................ 48

5.1.3

Water Retention/Moisture Characteristic ...................................................................... 49

5.1.4

Soil Salinity/Sodicity ...................................................................................................... 52

TRANSITIONAL RED BROWN EARTHS ............................................................................ 53 6.1.1

Physical Composition..................................................................................................... 53

6.1.2

Water Movement ............................................................................................................ 66

6.1.3

Water Retention/Moisture Characteristic ...................................................................... 73

6.1.4

Soil Salinity/Sodicity ...................................................................................................... 80

RED BROWN EARTHS............................................................................................................ 85 7.1

SOILS OF THE UPPER HILLSLOPES .............................................................................................. 85

7.1.1

Physical composition ..................................................................................................... 85

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7.1.2 7.2

Water Movement ............................................................................................................ 85

SOILS OF THE LOWER HILLSLOPES ............................................................................................ 86

7.2.1 7.3

Physical Composition..................................................................................................... 86

WATER MOVEMENT ................................................................................................................. 90

7.3.2 7.4

Water Retention/Moisture Characteristic ...................................................................... 92

SOILS OF THE PLAINS – SUBPLASTIC SUBSOIL GROUP ................................................................ 94

7.4.1 7.5

8

9

10

Physical composition ..................................................................................................... 94

SOILS OF THE PLAINS (NORMAL SUBSOIL GROUP)..................................................................... 96

7.5.1

Physical Composition..................................................................................................... 96

7.5.2

Water Movement .......................................................................................................... 102

7.5.3

Water Retention/Moisture Characteristic .................................................................... 105

7.5.4

Soil Salinity/Sodicity .................................................................................................... 109

SANDS OVER CLAY (SOLODIZED SOLONETZ SOILS) ............................................... 111 8.1.1

Physical composition ................................................................................................... 111

8.1.2

Water movement........................................................................................................... 118

8.1.3

Water Retention/Moisture Characteristic .................................................................... 120

8.1.4

Soil Salinity/Sodicity .................................................................................................... 124

DEEP SANDY SOILS.............................................................................................................. 126 9.1.1

Physical Composition................................................................................................... 126

9.1.2

Water movement........................................................................................................... 127

9.1.3

Water Retention/Moisture Characteristic ...................................................................... 128

TYPICAL SOIL PROPERTIES FOR SOIL GROUPS........................................................ 129 10.1

CLAYS ............................................................................................................................... 129

10.1.1

Self mulching clays....................................................................................................... 129

10.1.2

Hard setting clays ........................................................................................................ 132

10.2

TRANSITIONAL RED BROWN EARTHS .................................................................................. 134

10.2.1 10.3

Exchangeable sodium percentage................................................................................ 136

RED BROWN EARTHS ........................................................................................................ 137

10.3.1

Soils of the upper hillslopes ......................................................................................... 137

10.3.2

Soils of the lower hillslopes.......................................................................................... 137

10.3.3

Soils of the plains (subplastic subsoil group)............................................................... 138

10.3.4

Plastic soils of the plains ( normal subsoil group)....................................................... 139

10.4

SANDS OVER CLAY............................................................................................................. 142

10.5

DEEP SANDS....................................................................................................................... 144

11

CONCLUSION ......................................................................................................................... 147

12

BIBLIOGRAPHY..................................................................................................................... 148

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TABLE OF FIGURES FIGURE 1-1 LOCATION OF THE MIA AND CIA.......................................................................................... 1 FIGURE 3-1 DIAGRAMMATIC SCHEME OF THE CHARACTERISTIC SEQUENCE OF SOILS ON THE WIDGELLI PARNA ............................................................................................................................................. 8

FIGURE 3-2 RELATIONSHIP OF SUBPLASTICITY TO TOPOGRAPHY IN THE BINGAR PARNA. SP(1), FIRST DEGREE SUBPLASTICITY; SUBPLASTICITY;

SP(11), SECOND DEGREE SUBPLASTICITY; SP(111), THIRD DEGREE

+

SP(111 ), HARDPAN; NP, NORMAL PLASTICITY .................................................. 12

FIGURE 4-1 AVERAGE PARTICLE SIZE DISTRIBUTION WITH DEPTH FOR SELF MULCHING CLAYS .............. 27 FIGURE 4-2 CUMULATIVE PROBABILITY DISTRIBUTION OF PARTICLE SIZE OF SELF MULCHING CLAYS IN THE 0-0.1 M LAYER ....................................................................................................................... 28

FIGURE 4-3 CUMULATIVE PROBABILITY DISTRIBUTION OF PARTICLE SIZE OF SELF MULCHING CLAYS IN THE 0.2-0.3 M LAYER .................................................................................................................... 29

FIGURE 4-4 BULK DENSITY VARIATION WITH DEPTH FOR SELF MULCHING CLAYS .................................. 31 FIGURE 4-5 MEAN CUMULATIVE INFILTRATION CURVES FOR CLAYS TAKEN FROM VAN DER LELIJ AND TALSMA (1977)............................................................................................................................. 32 FIGURE 4-6 CUMULATIVE PROBABILITY DISTRIBUTION OF HYDRAULIC CONDUCTIVITY ......................... 34 FIGURE 4-7 VOLUMETRIC MOISTURE CONTENT PROFILES OF A WUNNAMURRA CLAY ............................ 36 FIGURE 4-8 VARIATION OF VOLUMETRIC WATER CONTENTS AT 1500 kPA FOR SELF-MULCHING CLAYS 39 FIGURE 4-9 VARIATION OF VOLUMETRIC WATER CONTENTS AT 10 kPA FOR SELF-MULCHING CLAYS .... 41 FIGURE 4-10 ELECTRICAL CONDUCTIVITY VARIATION WITH DEPTH FOR SELF MULCHING CLAYS ........... 42 FIGURE 4-11 ESP VARIATION WITH DEPTH FOR SELF MULCHING CLAYS................................................. 43 FIGURE 5-1 VARIATION OF BULK DENSITY WITH DEPTH FOR HARD SETTING CLAYS ............................... 47 FIGURE 5-2 VARIOUS VOLUMETRIC MOISTURE CONTENTS AT PERMANENT WILTING POINT. ................... 50 FIGURE 5-3 VARIATION OF VOLUMETRIC MOISTURE CONTENTS AT FIELD CAPACITY FOR HARD SETTING CLAYS ........................................................................................................................................... 51

FIGURE 5-4 SOIL MOISTURE CHARACTERISTIC CURVE FOR A BILLABONG CLAY TAKEN FROM SHARMA (1971) ........................................................................................................................................... 52 FIGURE 6-1 AVERAGE PARTICLE SIZE DISTRIBUTION WITH DEPTH FOR TRANSITIONAL RED BROWN EARTHS.......................................................................................................................................... 56

FIGURE 6-2 CUMULATIVE PROBABILITY DISTRIBUTION OF PARTICLE SIZE FOR TRANSITIONAL RED BROWN EARTHS IN THE 0-0.1 M LAYER ...................................................................................................... 59

FIGURE 6-3 CUMULATIVE PROBABILITY DISTRIBUTION OF PARTICLE SIZE FOR TRANSITIONAL RED BROWN EARTHS IN THE 0.2-0.3 M LAYER ................................................................................................... 59

FIGURE 6-4 VARIATION OF BULK DENSITY WITH DEPTH FOR TRANSITIONAL RED BROWN EARTHS ......... 63 FIGURE 6-5 SHORT-TERM INFILTRATION DURING PONDING ON AN INITIALLY DRY SOIL.......................... 66 FIGURE 6-6 FREQUENCY DISTRIBUTION OF INFILTRATION TOTALS MEASURED OVER A 2-16 WEEK PERIOD OF PERMANENT PONDING ON TRANSITIONAL RED BROWN EARTHS (VAN DER LELIJ AND TALSMA

1977)............................................................................................................................................. 67 FIGURE 6-7 CUMULATIVE INFILTRATION FOR TRANSITIONAL RED BROWN EARTHS AS MEASURED BY VAN DER LELIJ AND TALSMA (1977)..................................................................................................... 68

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FIGURE 6-8 CUMULATIVE PROBABILITY DISTRIBUTIONS OF HYDRAULIC CONDUCTIVITIES OF TRANSITIONAL RED BROWN EARTHS, AFTER LOVEDAY ET AL. (1978)............................................ 70

FIGURE 6-9 VARIATION OF VOLUMETRIC WATER CONTENTS AT 1500 kPA FOR TRANSITIONAL RED BROWN EARTHS ............................................................................................................................. 77

FIGURE 6-10 VARIATION OF VOLUMETRIC WATER CONTENTS AT 10 kPA FOR TRANSITIONAL RED BROWN EARTHS.......................................................................................................................................... 79

FIGURE 6-11 VARIATION OF ELECTRICAL CONDUCTIVITY (MS/CM) WITH DEPTH.................................... 81 FIGURE 6-12 VARIATION OF ESP WITH DEPTH ....................................................................................... 84 FIGURE 7-1 AVERAGE PARTICLE SIZE DISTRIBUTION OF SOILS OF THE LOWER HILLSLOPES .................... 87 FIGURE 7-2 VARIATION OF BULK DENSITY (KG/M3) WITH DEPTH FOR SOIL OF THE LOWER HILLSLOPES .. 89 FIGURE 7-3 VOLUMETRIC MOISTURE CONTENT PROFILE OF A HANWOOD LOAM AS DETERMINED BY MEYER (1992): “DRY END” = PERMANENT WILTING POINT, “WET END” = FIELD CAPACITY ......... 92 FIGURE 7-4 VOLUMETRIC MOISTURE CONTENT PROFILES OF A JONDARYAN LOAM, TALSMA (1963) ..... 93 FIGURE 7-5 CUMULATIVE PROBABILITY DISTRIBUTION OF PARTICLE SIZE IN PLASTIC SOILS OF THE PLAINS,

0-0.1 M............................................................................................................................. 99

FIGURE 7-6 CUMULATIVE PROBABILITY DISTRIBUTION OF PARTICLE SIZE IN PLASTIC SOILS OF THE PLAINS - NORMAL, 0.2-0.3 M ................................................................................................................... 100 FIGURE 7-7 VARIATION OF DENSITY WITH DEPTH FOR SOILS OF THE PLAINS - NORMAL........................ 101 FIGURE 7-8 MEAN CUMULATIVE INFILTRATION CURVES (MM) FOR SOILS OF THE PLAINS – NORMAL, VAN DER LELIJ AND TALSMA (1977)................................................................................................... 103

FIGURE 7-9 VARIATION OF VOLUMETRIC WATER CONTENTS AT 1500 kPA FOR PLASTIC SOILS OF THE PLAINS ......................................................................................................................................... 106

FIGURE 7-10 VARIATION OF VOLUMETRIC WATER CONTENTS AT FIELD CAPACITY ............................... 108 FIGURE 7-11 VARIATION OF ESP WITH DEPTH FOR PLASTIC SOILS OF THE PLAIN ................................. 110 FIGURE 8-1 CUMULATIVE PROBABILITY DISTRIBUTION OF PARTICLE SIZE, 0-0.1 M.............................. 115 FIGURE 8-2 CUMULATIVE PROBABILITY DISTRIBUTION OF PARTICLE SIZE, 0.2-0.3 M........................... 115 FIGURE 8-3 VARIATION OF BULK AND AGGREGATE DENSITIES WITH DEPTH OF SANDS OVER CLAY SOILS .................................................................................................................................................... 117 FIGURE 8-4 MEAN CUMULATIVE INFILTRATION DURING PONDING OF THULABIN AND COBRAM SANDY LOAMS.

FROM VAN DER LELIJ AND TALSMA (1977).................................................................... 118

FIGURE 8-5 VARIATION OF MOISTURE CONTENTS AT 1500 kPA FOR SANDS OVER CLAY ...................... 122 FIGURE 8-6 VARIATION OF MOISTURE CONTENTS AT 10 kPA ............................................................... 123 FIGURE 8-7 VARIATION OF ESP WITH DEPTH FOR SANDS OVER CLAY SOILS ......................................... 125 FIGURE 9-1 VOLUMETRIC MOISTURE CONTENT PROFILES OF A BANNA SAND AT 1500 AND 10 kPA ..... 128 FIGURE 10-1 AVERAGE PARTICLE SIZE DISTRIBUTION, 0.01 M. ............................................................ 145 FIGURE 10-2 AVERAGE PARTICLE SIZE DISTRIBUTION, 0.2 – 0.3 M. ..................................................... 145 FIGURE 10-3 CUMULATIVE INFILTRATION OVER A SIXTEEN WEEK PERIOD, 1: SOLIDIZED SOLONETZ SOILS,

2: SELF MULCHING CLAY SOILS, 3: PLASTIC SOILS OF THE PLAINS, 4: TRANSITIONAL SOILS.

(VAN DER LELY AND TALSMA 1977) .......................................................................................... 146 FIGURE 10-4 AVAILABLE WATER (MM) IN THE TOP 0.3 M OF SOIL FOR SELECTED SOIL GROUPS ........... 146

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LIST OF TABLES TABLE 3-1 DESCRIPTIONS OF THE SOIL CATEGORIES .............................................................................. 15 TABLE 4-1 RANGES OF PARTICLE SIZE DISTRIBUTION FOR SELF-MULCHING CLAYS (LOVEDAY ET AL. 1966)............................................................................................................................................. 24 TABLE 4-2 RANGES OF PARTICLE SIZE DISTRIBUTION FOR SELF-MULCHING CLAYS (LOVEDAY ET AL. (1978) ........................................................................................................................................... 25 TABLE 4-3 PARTICLE SIZE ANALYSIS OF SELF MULCHING CLAYS ............................................................ 26 TABLE 4-4 STATISTICAL DATA RELATING TO PARTICLE SIZE ANALYSIS OF SELF-MULCHING CLAYS IN THE 0-0.1 M LAYER .............................................................................................................................. 27 TABLE 4-5 STATISTICAL DATA RELATING TO PARTICLE SIZE ANALYSIS OF SELF MULCHING CLAYS IN THE 0.2-0.3 M LAYER ........................................................................................................................... 28 TABLE 4-6 BULK DENSITIES OF SELF-MULCHING CLAYS ......................................................................... 30 TABLE 4-7 STATISTICAL ANALYSIS OF BULK DENSITY DATA OF SELF-MULCHING CLAYS (KG/M3) ........... 31 TABLE 4-8 STATISTICAL ANALYSIS OF HYDRAULIC CONDUCTIVITIES OF SELF-MULCHING CLAYS (MM/DAY)...................................................................................................................................... 33 TABLE 4-9 HYDRAULIC CONDUCTIVITY FOR SELF-MULCHING CLAY DURING PONDING (MM/DAY).......... 35 TABLE 4-10 RANGES OF 1500 kPA MOISTURE CONTENTS (M 3/M3) OF SELF MULCHING CLAYS, LOVEDAY ET AL.

(1978) ................................................................................................................................. 37

TABLE 4-11 1500 kPA VOLUMETRIC MOISTURE CONTENTS OF SELF-MULCHING CLAYS .......................... 38 TABLE 4-12 STATISTICAL ANALYSIS OF VOLUMETRIC WATER CONTENTS AT 1500 kPA ......................... 38 TABLE 4-13 10 kPA VOLUMETRIC MOISTURE CONTENTS OF SELF-MULCHING CLAYS .............................. 40 TABLE 4-14 STATISTICAL ANALYSIS OF VOLUMETRIC WATER CONTENTS AT 10 kPA ............................. 40 TABLE 4-15 ESP FOR SELF-MULCHING CLAYS ........................................................................................ 43 TABLE 4-16 ANALYSIS OF ESP DATA OF SELF-MULCHING CLAYS ........................................................... 44 TABLE 5-1 PARTICLE SIZE DISTRIBUTION OF HARD SETTING CLAYS........................................................ 45 TABLE 5-2 BULK DENSITIES OF HARD SETTING CLAYS ............................................................................ 46 TABLE 5-3 HYDRAULIC CONDUCTIVITY OF A BILLABONG CLAY (SHARMA 1972) .................................. 48 TABLE 5-4 PERMANENT WILTING POINT VOLUMETRIC MOISTURE CONTENTS FOR HARD SETTING CLAYS 50 TABLE 5-5 VOLUMETRIC MOISTURE CONTENT MEASUREMENTS AT FIELD CAPACITY FOR HARD SETTING CLAYS ........................................................................................................................................... 51

TABLE 5-6 ELECTRICAL CONDUCTIVITIES OF HARD SETTING CLAYS ...................................................... 52 TABLE 6-1 RANGES OF PARTICLE SIZE ANALYSIS FOR TRANSITIONAL RED BROWN EARTHS LOVEDAY ET AL. (1978)................................................................................................................ 53 TABLE 6-2 RANGES OF PARTICLE SIZE DISTRIBUTION FOR TRANSITIONAL RED BROWN EARTHS, LOVEDAY ET AL. (1966). ................................................................................................................................ 54

TABLE 6-3 PARTICLE SIZE DISTRIBUTION OF TRANSITIONAL RED BROWN EARTHS.................................. 57 TABLE 6-4 STATISTICAL DATA RELATING TO PARTICLE SIZE ANALYSIS OF TRANSITIONAL RED BROWN EARTHS FOR THE 0-0.1 M LAYER ................................................................................................... 58

TABLE 6-5 STATISTICAL DATA RELATING TO PARTICLE SIZE ANALYSIS OF TRANSITIONAL RED BROWN EARTHS FOR THE 0.2-0.3 M LAYER ................................................................................................ 58

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TABLE 6-6 BULK DENSITIES OF TRANSITIONAL RED BROWN EARTHS ...................................................... 62 TABLE 6-7 STATISTICAL DATA RELATING TO BULK DENSITIES OF TRANSITIONAL RED BROWN EARTHS (KG/M3) ......................................................................................................................................... 63 TABLE 6-8 POROSITY OF MARAH CLAY LOAM AS FOUND BY MCINTYRE ET AL. (1982) .......................... 64 TABLE 6-9 POROSITY MEASUREMENTS OF TRANSITIONAL RED BROWN EARTHS (M3/M3). LOVEDAY ET AL. (1966) ........................................................................................................................................... 65 TABLE 6-10 TOTAL POROSITY OF TUPPAL CLAY (M3/M3), TALSMA (1963) ............................................. 65 TABLE 6-11 INFILTRATION RATES (MM/DAY) AS MEASURE BY LOVEDAY ET AL. (1984) ......................... 68 TABLE 6-12 STATISTICAL DATA RELATING TO SATURATED HYDRAULIC CONDUCTIVITIES OF TRANSITIONAL RED BROWN EARTHS AS DETERMINED BY LOVEDAY ET AL. (1978) ........................ 69

TABLE 6-13 SATURATED HYDRAULIC CONDUCTIVITY (MM/DAY) MEASURED BY LOVEDAY ET AL. (1984) ...................................................................................................................................................... 71 TABLE 6-14 HYDRAULIC CONDUCTIVITY (MM/DAY) AND ITS VARIATION WITH TIME DURING PONDING, MCINTYRE ET AL. (1982)............................................................................................................... 72 TABLE 6-15 POTENTIAL GRADIENT AND HYDRAULIC CONDUCTIVITY OF A TRANSITIONAL RED BROWN EARTHS DURING PONDING, VAN DER LELIJ AND TALSMA (1977) .................................................. 72

TABLE 6-16 ESTIMATED HYDRAULIC CONDUCTIVITY OF A WILLBRIGGIE CLAY LOAM WITH A HIGH WATERTABLE,

SIDES ET AL 1993. .................................................................................................. 73

TABLE 6-17 AVAILABLE WATER OF A TUPPAL CLAY, TALSMA (1963) ................................................... 74 TABLE 6-18 RANGES OF 1500 KPA MOISTURE CONTENTS (M3/M3) OF TRANSITIONAL RED BROWN EARTHS, LOVEDAY ET AL. (1966) ................................................................................................................ 75 TABLE 6-19 RANGES OF 1500 kPA MOISTURE CONTENTS (M 3/M3) FOR TRANSITIONAL RED BROWN EARTHS,

LOVEDAY ET AL. (1978).................................................................................................. 75

TABLE 6-20 1500 kPA MOISTURE CONTENTS (M 3/M3) OF TRANSITIONAL RED BROWN EARTHS ............... 76 TABLE 6-21 STATISTICAL DATA RELATING TO 1500 kPA VOLUMETRIC MOISTURE CONTENT STUDIES ON TRANSITIONAL RED BROWN EARTHS .............................................................................................. 77

TABLE 6-22 10 kPA MOISTURE CONTENTS (M 3/M3) OF TRANSITIONAL RED BROWN EARTHS AS MEASURED BY LOVEDAY ET AL.

(1966) ........................................................................................................... 78

TABLE 6-23 10 kPA VOLUMETRIC MOISTURE CONTENTS (M 3/M3) OF TRANSITIONAL RED BROWN EARTHS ...................................................................................................................................................... 78 TABLE 6-24 STATISTICAL DATA RELATING TO 10 kPA VOLUMETRIC MOISTURE CONTENT (M 3/M3) STUDIES ON TRANSITIONAL RED BROWN EARTHS .......................................................................... 79

TABLE 6-25 MEAN ELECTRICAL CONDUCTIVITIES (MS/CM) OF TRANSITIONAL RED BROWN EARTHS LOVEDAY ET AL. (1978)................................................................................................................. 80 TABLE 6-26 STATISTICAL DATA RELATING TO ELECTRICAL CONDUCTIVITY (MS/CM) OF TRANSITIONAL RED BROWN EARTHS ...................................................................................................................... 82

TABLE 6-27 ESP OF TRANSITIONAL RED BROWN EARTHS ....................................................................... 83 TABLE 6-28 STATISTICAL DATA RELATING TO ESP OF TRANSITIONAL RED BROWN EARTHS .................. 84 TABLE 7-1 HYDRAULIC CONDUCTIVITIES (MM/DAY) OF SUB-PLASTIC SOILS OF THE UPPER HILLSLOPES, AFTER VAN DER LELIJ (1974). ....................................................................................................... 86

XI

TABLE 7-2 PARTICLE SIZE DISTRIBUTIONS OF SOILS OF THE LOWER HILLSLOPES .................................... 87 TABLE 7-3 BULK DENSITIES OF SOILS OF THE LOWER HILLSLOPES .......................................................... 88 TABLE 7-4 HYDRAULIC CONDUCTIVITIES (MM/DAY) OF SOILS OF THE LOWER HILLSLOPES, AFTER VAN DER LELIJ (1974)........................................................................................................................... 91

TABLE 7-5 10 AND 1500 kPA VOLUMETRIC MOISTURE CONTENTS OF JONDARYAN LOAM, TALSMA (1963) ........................................................................................................................................... 93 TABLE 7-6 PARTICLE SIZE DISTRIBUTION OF PLASTIC SOILS OF THE PLAINS, AFTER SINCLAIR ET AL (1994) ...................................................................................................................................................... 94 TABLE 7-7 MEAN BULK DENSITIES (KG/M3) OF INTACT CORES (0 – 5 CM) AT DISTANCES AWAY FROM THE VINE ROW FOR PLASTIC SOILS OF THE PLAINS ................................................................................ 95

TABLE 7-8 HYDRAULIC CONDUCTIVITIES (MM/DAY) OF SUB SOIL PLASTIC SOILS OF THE PLAINS, AFTER VAN DER LELIJ (1974). .................................................................................................................. 96

TABLE 7-9 RANGES OF PARTICLE SIZE DISTRIBUTION FOR PLASTIC SOILS OF THE PLAINS LOVEDAY ET AL. (1966) ........................................................................................................................................... 97 TABLE 7-10 RANGES OF PARTICLE SIZE FOR SOILS OF THE PLAINS, LOVEDAY ET AL. (1978) .................. 97 TABLE 7-11 PARTICLE SIZE DISTRIBUTION OF SOILS OF THE PLAINS – NORMAL ...................................... 98 TABLE 7-12 STATISTICAL DATA RELATING TO SIZE ANALYSIS OF PLASTIC SOILS OF THE PLAINS – NORMAL, IN THE 0-0.1 M LAYER.................................................................................................... 98

TABLE 7-13 STATISTICAL DATA RELATING TO PARTICLE SIZE ANALYSIS OF SOILS OF THE PLAINS – NORMAL, IN THE 0.2-0.3 M LAYER................................................................................................. 99

TABLE 7-14 DENSITIES OF PLASTIC SOILS OF THE PLAINS – NORMAL (KG/M3) ...................................... 101 TABLE 7-15 HYDRAULIC CONDUCTIVITY (MM/DAY) OF SOILS OF THE PLAINS – NORMAL, VAN DER LELIJ AND TALSMA (1977) ................................................................................................................... 104

TABLE 7-16 POTENTIAL GRADIENT AND HYDRAULIC CONDUCTIVITY OF TWO SOILS OF THE PLAINS – NORMAL, DURING PONDING, VAN DER LELIJ (1974).................................................................... 105

TABLE 7-17 1500 kPA MOISTURE CONTENTS (M 3/M3) OF NORMAL SOILS OF THE PLAINS ...................... 106 TABLE 7-18 STATISTICAL DATA RELATING TO STUDIES ON 1500 kPA VOLUMETRIC MOISTURE CONTENTS FOR NORMAL PLAINS SOILS.......................................................................................................... 107

TABLE 7-19 10 kPA VOLUMETRIC MOISTURE CONTENTS OF PLASTIC SOILS OF THE PLAIN .................... 108 TABLE 7-20 STATISTICAL DATA RELATING TO FIELD CAPACITIES OF PLASTIC SOILS OF THE PLAINS ..... 109 TABLE 7-21 ELECTRICAL CONDUCTIVITIES (MS/CM) OF PLASTIC SOILS OF THE PLAINS LOVEDAY ET AL. (1978) ......................................................................................................................................... 109 TABLE 7-22 ESP OF NORMAL PLAINS SOILS .......................................................................................... 110 TABLE 8-1 RANGES OF PARTICLE SIZE DISTRIBUTION FOR SANDS OVR CLAY SOILS LOVEDAY (1966) .. 111 TABLE 8-2 RANGES OF PARTICLE SIZE DISTRIBUTION FOR SANDS OVER CLAY SOILS LOVEDAY ET AL. (1978) ......................................................................................................................................... 112 TABLE 8-3 PARTICLE SIZE DISTRIBUTION OF SOLODIZED SOLONETZ SOILS ........................................... 113 TABLE 8-4 STATISTICAL DATA RELATING TO PARTICLE SIZE ANALYSIS OF SOLODIZED SOLONETZ SOILS, 0-0.1 M ........................................................................................................................................ 114

XII

TABLE 8-5 STATISTICAL DATA RELATING TO PARTICLE SIZE ANALYSIS OF SOLODIZED SOLONETZ SOILS, 0.2-0.3 M ..................................................................................................................................... 114 TABLE 8-6 BULK AND AGGREGATE DENSITIES OF SANDS OVER CLAY SOILS ......................................... 116 TABLE 8-7 POTENTIAL GRADIENT AND HYDRAULIC CONDUCTIVITY OF A SANDS OVER CLAY SOIL DURING PONDING...................................................................................................................................... 119

TABLE 8-8 MEAN HYDRAULIC CONDUCTIVITIES (MM/DAY) OF SANDS OVER CLAY SOILS IN THE MIRROOL IRRIGATION AREA, VAN DER LELIJ (1974)................................................................... 120 TABLE 8-9 VOLUMETRIC WATER CONTENTS AT 1500 kPA FOR SANDS OVER CLAY .............................. 121 TABLE 8-10 ANALYSIS OF MOISTURE CONTENTS AT 1500 kPA FOR SANDS OVER CLAY ....................... 122 TABLE 8-11 VOLUMETRIC WATER CONTENTS AT 10 kPA ..................................................................... 123 TABLE 8-12 ANALYSIS OF MOISTURE CONTENTS AT 10 kPA................................................................. 124 TABLE 8-13 ELECTRICAL CONDUCTIVITY OF SANDS OVER CLAY SOILS (MS/CM).................................. 124 TABLE 8-14 ESP OF SANDS OVER CLAY SOILS ...................................................................................... 125 TABLE 9-1 HYDRAULIC CONDUCTIVITY (MM/DAY) OF A DEEP SANDY SOIL .......................................... 127 TABLE 10-1 TYPICAL VALUES OF PROPERTIES OF SELF MULCHING CLAYS ............................................ 132 TABLE 10-2 TYPICAL VALUES OF PROPERTIES OF HARD SETTING CLAYS .............................................. 133 TABLE 10-3 TYPICAL VALUES OF PROPERTIES OF TRANSITIONAL RED BROWN EARTHS ........................ 136 TABLE 10-4 TYPICAL VALUES OF PROPERTIES OF SOILS OF THE LOWER HILLSLOPES ............................ 138 TABLE 10-5 TYPICAL VALUES OF PROPERTIES OF SUBPLASTIC SOIL OF THE HILLSLOPES ...................... 139 TABLE 10-6 TYPICAL VALUES OF NORMAL SOILS OF THE PLAINS .......................................................... 141 TABLE 10-7 TYPICAL VALUES OF PROPERTIES OF SOLODIZED SOLONETZ SOILS .................................... 144 TABLE 10-8 TYPICAL VALUES OF PROPERTIES OF DEEP SANDS ............................................................. 144

XIII

1

INTRODUCTION

The Murrumbidgee Irrigation Area (MIA) and Coleambally Irrigation Area (CIA) lie on the north eastern region of the Riverine plain. This is part of the Murray Darling Basin, the major catchment area of New South Wales. The MIA and CIA are irrigated from water diverted from the Murrumbidgee River, supplied by large catchment dams located in the Snowy Mountains. A locality map is shown in figure 1.1.

Figure 1-1 Location of the MIA and CIA

Soils are essential for farming, and knowledge of soil physical properties is essential to manage and utilise soils to their full extent. The MIA and CIA are reliant on farming enterprises for income, hence knowledge of soil physical properties is important, not only

1

in design and establishment of irrigation systems, but also for managing and sustaining the farming systems using predictive models and research.

This review has been undertaken to bring together soil physical property data for the MIA and CIA, previously documented in published and unpublished forms, into a single publication and to establish, where possible, general ranges of soil physical properties within soil groups which have similar characteristics.

Information on soil physical properties can be difficult and time consuming to locate, in many cases the information being located in unpublished reports and technical memorandums which are difficult to access. Therefore, there existed a need to update this information and compile it into a more useable format.

2

2

OBJECTIVES

The objectives of this review were to: 1/ Determine what data was available for soil properties in the MIA and CIA. 2/ Determine the soil physical data most useful to end users. 3/ Compile the available data. 4/ Determine characteristic values for properties of soils.

3

3.1

METHODOLOGY

Identification of important soil properties

The soil properties reviewed in this report were selected by correspondence with likely end users (e.g. surveyors, engineers, researchers and resource managers) of the data, and through verbal discussion with relevant CSIRO staff, Griffith. The initial facsimile survey sent to likely end users is included as appendix 1.

The survey tried to identify particular soil physical properties which were of importance to users of the data, and asked participants to place soil physical properties into three categories. These were: •

major importance;

•

secondary importance;

•

not important;

Responses to the surveys were received from seven people also listed in appendix 1. Responses varied considerably between correspondents, from which it was decided to review soil properties in four major areas, which were:

3

1/ Soil physical composition •

Particle size analysis

•

Bulk density

•

Porosity

2/ Water movement •

Infiltration

•

Hydraulic conductivity

3/ Water retention/moisture characteristic •

Available water

•

Moisture characteristic

4/ Soil salinity/sodicity •

Electrical conductivity

•

Exchangeable sodium percentage

The properties chosen above are the most important for irrigated agriculture in terms of water movement and retention.

Particle size distribution influences qualities such as infiltration, moisture and nutrient retention, drainage and soil susceptibility to erosion. Knowledge of the particle size distribution can also give a general indication of other soil properties which may not be known, such as hydraulic conductivity and moisture characteristics.

The bulk density of soil is important as excessively high bulk densities inhibit root penetration and impede drainage. Infiltration and permeability rates are also affected by bulk density.

Porosity refers to the nature and amount of voids between and within particles. An abundance of large air filled pores is associated with stable aggregates and a productive 4

soil. Porosity also has an effect on other soil properties such as infiltration and hydraulic conductivity.

Infiltration is a particularly important soil property and serves as a guide to the most appropriate method of irrigation. It is also important in irrigation design and has a major control on size of basin or length of furrow and the optimum rate of water application. Hydraulic conductivity is used to assess waterlogging problems and as the basis of designing in-field and regional drainage. Knowledge of hydraulic conductivity is also particularly important in assessing possible problems due to high watertables.

Water retention and moisture characteristics of soils indicate the capacity of a soil to retain water for plants. Irrigation scheduling depends on the amount of water available to plants and schedules are based on the amount of water available in particular soils. Measurements of available water are generally taken as the difference in water content of the soil between field capacity and permanent wilting point. Field capacity may be defined as the amount of water held in the soil after drainage under gravity, Dent and Young (1981). In freely draining soils field capacity is reached within a few hours of saturation. In silts and clays equilibrium is reached only after a considerable time. For most crops the lower limit of available water, permanent-wilting point, corresponds to a soil water tension of 1500 kPa.

Electrical conductivity measurements were included in order to assess the soils possible salinity problems. It should be remembered however that soil salinity can change rapidly, it can be reduced by leaching, or can increase by rising groundwater or inadequate drainage.

Exchange sodium percentages were also included in the review to assess sodicity, which has a great influence on the stability of the soil and hence hydraulic conductivity and soil moisture retention.

5

3.1.1

Data collection and selection

In determining available data relating to soil physical properties in the MIA and CIA, initial searches were conducted on an unpublished soil database being constructed by Mr. Geoff Beecher at NSW Agriculture, Yanco. The database contained 691 references to soil studies undertaken in the NSW Riverina. Key search words included each selected soil property along with associated terms such as Murrumbidgge Irrigation Area, Coleambally Irrigation Area, soil properties, soil characteristics, soil groups and relevant authors along with other associated terms. Selected papers were then analysed and those which documented physical soil properties were collected. Searches of the CSIRO Structured Information Manager (SIM) database were also made using the keywords mentioned above.

The results from the searches of SIM and Mr Beechers database were then compiled and manual searches made on the bibliography of each paper for further references. Sources of reference material relating to soil properties were also asked for in the fax survey of potential users of the review, however responses were limited.

Reports and papers were chosen based on the suitability of the material for inclusion in the review. This was determined on a number of factors:

1/ Accurate identification of the soil type, so that the data could be associated with a particular soil group. In some cases information on particular soil properties was found however this information was not linked to a particular soil type.

2/ Soil properties over a range of soil types or a large number of soil properties, in one paper, were used in the review for one particular soil type.

3/ The purpose of the study was considered, studies which were undertaken for the sole purpose of determining soil properties, were chosen in preference to those, which measured limited soil properties to support other research. 6

4/ The methodology used to measure particular soil properties was also considered when reviewing data and emphasis was placed on collecting reports which were comparable on a property basis. For example only electrical conductivities of 1:5 solution extracts were collected.

5/ The relative importance of the soil e.g. area covered, economical importance, was considered.

In total 78 references of published literature were collected and used in this review along with some unpublished data from CSIRO staff.

3.1.2

Geomorphology of the Area

The MIA and CIA both lie on the Riverine plain of south eastern Australia across which the Lachlan, Murrumbidgee, and Murray rivers flow. This alluvial plain is built up of sediments from ancient streams. These sedimentary deposits are interbedded with wind blown clay deposits known as parna, Butler and Hutton, (1956).

Butler and Hutton (1956) indicated the occurrence of three periods of parna deposition, each being followed by a period of soil development. Between each parna deposition there was a sporadic deposition of riverine materials associated with erosion, but lack of soil development on these indicated that the riverine phases were followed closely by the next parna deposition. The lowest and hence oldest deposition and soil forming phase is called the Cocoparra, van Dijk (1958). The next deposition of parna and its associated riverine material is called Barellan. The final deposition forms the greater part of the present day land surface and is called the Widgelli parna and its related riverine material is called Hanwood. Within the MIA a characteristic phase of the Widgelli parna occurs, known as the Tabbita phase .

7

Highly differentiated soils occur on the parna layer and these include brown solodized soils in the dune zones, red-brown earths on the hills, and red-brown earths and grey and brown soils of heavy texture on the riverine plains. The variation in soil types is caused by belts of riverine alluvium of varying width traversing the parna, variations in depth of the Widgelli parna sheet, fuluviatile-colluvial modifications of varying degree, differences in age of fluviatile deposits and drainage conditions which determine the main characteristics of the landscape and its soils, van Dijk (1961). A schematic diagram of the characteristic sequence of soils on the Widgelli parna is shown in figure 3.1.

Figure 3-1 Diagrammatic scheme of the characteristic sequence of soils on the Widgelli parna

3.1.3

Description and classification of the soils

The above investigation of the geomorphology of the area and review of the soil surveys by van Dijk (1958), Stannard (1970), Taylor and Hooper (1938) and van Dijk (1961), revealed that although there were at least 94 different soil types mapped within the CIA and MIA, the soils could be grouped together based on morphological similarity and recurrent patterns of associations. The soils of the area were found to fit into the 8

following five broad soil groups, which were then subdivided on prominent soil characteristics. These 5 groups were: 1. Clays 2. Red Brown Earths 3. Transitional red brown earths Red Brown Earths 4. Sands over Clay 5. Deep Sands

Typical properties of each of the soil groups are shown in Table 3.1.

3.1.3.1 Clays

There are both grey and brown clays which have been kept together, however, two sub groups have been made. Those with crumbly calcareous surface horizons (self-mulching clays) and those with massive non-calcareous surface soils (hard setting clays).

A) Self-mulching clays

These crumbly soils show virtually no change in texture from the surface downward with approximately 50-60% clay throughout. The fine aggregation of the surface soil gives the “self-mulching” property and is usually best developed when dry. In some instances the surface soil may be somewhat crusted but usually the crust is easily broken up. All soil profiles have in common very aggregated and dense subsoil.

Van Dijk and Talsma (1964) found that lime percentages for the upper limit of 10 gilgai soils were found to vary between 0.5% and 2%, occasionally reaching 3.5%, with slightly higher figures for the deeper sub soil. Table 3.1 shows a typical profile of a self-mulching clay.

9

B) Hard setting clays

The texture of their dense surface clay horizons is slightly lighter than that of the subsoil; lime concentrations are only encountered in small quantities below 0.45 m. The main soil type representing this sub group is Riverina clay.

3.1.3.2 Red-brown earths

This group comprises soils with a texture contrast profile, with a loamy or sandy surface soil more than 0.1 m deep, changing abruptly to clay subsoil. The surface soil may have a weakly developed bleached zone in the lower part, while the subsoil is relatively dense to well structured and may be subplastic. A typical profile is shown in table 3.1. An important characteristic of these soils is a property called subplasticity. Subplastic clays were described by Butler (1976) who stated: ‘These clays have the consistence properties of gravels, sands or loams; indeed the farmers refer to them as gravels and in their influence on drainage they seem to behave as gravels. During the manipulation of field texturing their apparent clayiness increases progressively until, at the end of five minutes it fully corroborates the mechanical analysis figures for heavy clay’. The property of subplasticity when highly developed imparts to the particular soil high mechanical and chemical stability and hence great resistance to puddling or dispersion. The implication is that abnormal cementation of particles occurs, McIntyre (1976).

Butler (1976) found that subplastic soils seem to be associated with aeolian clay (parna) mantles of regional extent, but not all exposures of parna are subplastic: those on the flatter and poorly drained sites are fully plastic. He also found a variation in the subplasticity with the age of the parna: there are three successive parna mantles and the stratigraphically older ones expressed a higher degree of subplasticity than the younger ones, Butler (1976).

10

In the MIA subplasticity in the soil types is found to be strongly related to success in irrigated horticulture, Talyor and Hooper, (1938). Therefore a red-brown earth, which has subplastic properties, is markedly different to a red-brown earth, which is plastic, the chemical and physical properties differ greatly. In order to group soils, which have similar physical and chemical properties a greater degree of differentiation between redbrown earths was required.

Subdivision of subplasticty was done by van Dijk (1958) who defined four degrees:

1/ First degree sub plasticity (SP1): The material works up by one textural grade during kneading for a few minutes, e.g. from loam to clay loam, or from light to medium clay.

2/ Second degree sub plasticity (SP11): The material works up by two or more textural grades, e.g. from loam to medium clay.

3/ Third degree subplasticity (SP111): The material feels like grit or coarse sand and can be puddled by hand only with great difficulty to show its real texture. e.g. medium clay A fourth degree of subplasticity has also been noted for highly sub plastic materials SP111+.

These degrees of subplasticity have been used in this report to further differentiate between red-brown earth soil types.

A high degree of subplasticity occurs only with good internal drainage. The same material may exhibit normal plastic properties or subplasticity of any degree depending on the drainage conditions. Therefore soils on hillslopes have a higher degree of subplasticity than similar soils of the plains. Subplastic soils of a lower degree may develop on the plains due to smaller micro relief or a thinner underlying parna layer which is particularly permeable and allows freer drainage of the upper soil layers, however red-brown earths of the plains rarely exceed a subplasticity degree greater than SP(1), van Dijk (1958). The relationship between the degree of subplasticity and drainage

11

conditions is shown in figure 3.2. This shows the relationship between subplasticity and topography in the Bingar parna layer, which underlies the Tabbita parna layer.

Figure 3-2 Relationship of subplasticity to topography in the Bingar parna. SP(1), first degree subplasticity; SP(11), second degree subplasticity; SP(111), third degree subplasticity; SP(111+), hardpan; NP, normal plasticity

Therefore three subgroups of red-brown earths were established using subplasticity degrees as defined by van Dijk (1958). These sub groups were soils of the hillslopes, soils of the lower hillslopes and soils of the plains. The soils of the plains have further been divided into those with a lighter subsoil, which may be slightly subplastic and those with normal subsoil which are fully plastic.

12

Subplastic soils of the upper hillslopes have subplasticity degrees of SP(111) and SP(111+), while subplastic soils of the lower hillslopes have subplasticty degrees between SP(11) and SP(111). Plastic soils of the plains, which have a lighter subsoil, correspond to a subplasticty degree of SP(1), while the normal subsoil subgroup are fully plastic.

3.1.3.3 Transitional red-brown earths

Transitional red brown earths are soils between clays and red-brown earths. The depth of the surface horizon of this group is only 0.08-0.1 m. The distribution of lime in the subsoil is similar to that of red brown earth’s and there is sometimes gypsum in the deep subsoil, particularly in the west of the CIA, van Dijk and Talsma (1964). The transitional red brown earths are the dominant soils of the plains, occurring in the highest proportion in the western and south western sections of the CIA.

3.1.3.4 Sands over clay

The soils of this group are solodized solonetz soils, having a marked texture contrast between light surface soils and heavy subsoils. The surface soils are quite variable in texture but are mostly sandy and the subsoils are generally very dense clays. The depth of the A horizon is variable from 0.13-0.6 m, with 0.2-0.3 m being the most common. Some surface horizons have a pronounced bleached zone in the lower part.

The characteristic feature of this group is the dense, coarsely structured clay subsoil. Under dry conditions this tough clay may be broken by wide vertical cracks into columns with a rounded top and these columns are frequently capped with a thin bleached sandysilty layer which is very brittle and powdery when dry, van Dijk and Talsma, (1964).

13

3.1.3.5 Deep sandy soil

The surface sand of these profiles is usually more than 0.9 m deep and the color is relatively uniform brown or pale grey-brown. A few centimeters at the surface are somewhat darker owing to the accumulation of organic matter and the brown color of the subsoil usually becomes more yellow with depth. The subsoil may contain several clay bands or a single sandy clay layer, there are sometimes slight amounts of lime and there may be bleached and cemented zones. Some profiles are undifferentiated sand to a depth of 3-4.5 m and more. The majority of the deep sands are of aeolian origin and occur as high and low dunes.

14

Table 3-1 Descriptions of the soil categories Feature

Selfmulching

Hard setting Red-brown Transitional Sands over Deep sands clays

earths

clays

red brown

Clay

earths redbrown earths

Topsoil

Self-

Hard setting Loam

mulching Depth

5-15cm

5cm or less

10-25cm

Loam to clay Sand to loam

loam

Less than

25-100cm

10cm

Subsoil

Heavy clay

Heavy clay

Heavy clay

Heavy clay

with lime

Sand

100cm or more

Cemented

Mottled

clayey sand clayey sand above a

grading to

mottled

light clay

medium clay Deep

Medium clay Medium clay, Sandy clay,

Medium clay, Medium

subsoil

with

often

often with

clay

(1-2m)

concretionar crystalline

micaceous

crystalline

sometimes

gypsum

becoming

y lime

often with

gypsum

Light clay

more sandy with depth Example

Yooroobla clay

Riverina clay Cobram loam

(After personal communication, Muirhead 1998)

15

Willbriggie

Danberry

Sandmount

loam

sand

sand

3.2

Soil types sorted into soil groups

All the soils of the CIA and MIA as surveyed by van Dijk (1958), Stannard (1970), Taylor and Hooper (1938) and van Dijk (1961) have been placed in the following groups. The horticultural soils are shown with an ‘H’ and the codes following some soils are the Northcote codes (Northcote, 1979) to which the soils have been mapped by various authors.

1) Clays:

1a) Self mulching clays: Coleambally Clay

Ug5.24, Ug5.28

Gogeldrie Clay Gundaline Clay Toganmain clay Wunnamurra Clay

Ug5.24, Ug 5.28, Ug5.34

Yooroobla Clay.

Ug 5.34

These clays have a heavier surface texture and calcareous surface horizon which breaks down to small aggregates under wetting and drying

1b) Hard setting clays: Billabong Clay Crommelin Clay Goolgumbla Clay Riverina Clay.

Ug5.6, Ug5.5

Wandook Clay

16

These are clays which have the texture of their dense surface horizons slightly lighter than that of the subsoil. Lime concentrations are not encountered until depths below 0.45 m

2) Red Brown Earths:

2a) Soils of the upper hillslopes: Ballingall loam

H

Lakeview loam

H

Merungle loam

H

Tharbogang loam

H

Wyangan loam

H

These soils have subplasticity classes SP(111) and SP(111+)

2b) Soils of the lower hillslopes: Bilbul clay loam

H

Griffith clay loam

H

Hanwood sandy loam and loam

H

Jondaryan loam and clay loam

H

Stanbridge sandy loam and loam

H

Yenda sandy loam and loam

H

Type 9

H

These soils have subplasticity classes SP(11) and SP(111)

2c) Soils of the plains: Subplastic group: Bilbul loam

H

Fivebough sandy loam

H

Griffith loam

H

17

Mirrool loam

H

Willimbong loam

H

Yoogali loam

H

Thulablin clay loam

These are plastic soils of the plains with subplasticity SP(1), the lighter subsoil group

Normal group: Beelbangera clay loam Camarooka clay loam

H

Camarooka sandy loam

H

Leeton clay loam

H

Types 8,12,13

H

Birganbigill clay loam Birganbigil sandy loam

Dr1.13, Dr1.33, Dr2.23

Birarbigill loam Bundure loam Cobram sandy loam

Dr2.23

Danberry clay loam Finley loam Marah sandy loam Moira loam Mundiwa sandy loam Thulabin loam Thulabin sandy loam

Dr2.23

Tuppal loam Willbriggie loam

Dr1.33

These are plastic soils of the plains without subplasicity, they are the ‘normal’ subsoil group

18

3) Transitional Red Brown Earths: Coree loam Coree clay loam Marah loam

Dr2.13

Marah clay loam

Dr2.13, Dr2.33

Morago clay Morago clay loam Mundiwa clay loam Tuppal clay Tuppal clay loam

Dd1.33, Dy2.3

Willbriggie clay

Dr2

Willbriggie clay loam

Dr1.13, Dr2.13, Db1.1, Db1.13

Yamma loam

These are transitional red brown earths between grey and brown clays and the red brown earths

4) Sands over clay: Boona sandy loam Cobram sandy loam Danberry sand Danberry sandy loam Danberry loamy sand

Db2.33

Finley sandy loam Hyandra sandy loam

H

Mycotha sand Pullega sand Pullega loamy sand Tenningerie sand Tenningerie sandy loam Thulabin sand

19

Tubbo sand Types 7,10,14

H

Wamoon sand Whymoul sand Whymoul loamy sand Yambil sandy loam

H

Yandera loam

H

Yandera sandy loam

H

These are soils which have marked texture contrast between light surface soils and heavy cemented subsoils

5) Deep Sandy Soils: Banna sand

H

Banandera sand Boona sand Eulo sand Jurambula sand Sandmount sand Utona sand Yarangery sand

These are soils which have a surface sand profile deeper than 1m.

20

3.3 Data analysis

3.3.1

Particle size analysis

Studies of particle size analysis rarely specified the method used, however where possible the methods used have been recorded with the associated data and included in the results section of this review. Most studies undertaken included the analysis of coarse sand (CS), fine sand (FS), silt (Si) and clay (C). Clay size fractions are commonly taken to be 0.2 mm. In some cases only limited data such as the clay content was given with no indication of silt of sand size fractions and in others sand fractions have simply been given rather than coarse and fine sand fractions. Ranges of coarse sand, fine sand, silt and clay have been compiled in most cases to depths of 0.3 m and comparisons of these results undertaken with average values, standard deviations, coefficient of variation, medians and geometric means. At depths greater than 0.3 m results from specific studies have been listed.

3.3.2

Bulk density and porosity

Density values have been recorded with associated moisture contents were possible, however in many studies moisture contents were not reported. In sandier soils moisture content does not affect bulk density dramatically but in clay soils the effect is more pronounced. In one particular study by Loveday et al. (1966) volumetric moisture contents have been calculated from aggregate densities, not bulk densities. In some cases for particular soil groups bulk density data was not plentiful hence aggregate densities were recorded. It should be noted that the bulk density of aggregates will be greater than that of the soil due to pore spaces between the clods Marshall and Holmes, (1979). All bulk densities have been converted to units of kg/m3.

21

Studies that undertook porosity measurements were difficult to find however, one major study undertaken by Loveday et al. (1966) contained a number of porosity measurements taken at various sites in the CIA. This report has been included as appendix 2.

3.3.3

Infiltration

Infiltration of water into soils had been measured in numerous ways using different instrumentation. The method used to measure infiltration was documented together with the results. Infiltration measurements included in this report have come largely from ponding of the soil over extended time periods. Measurements of infiltration on dry soil were not well represented, and is difficult to measure particularly on cracking clay soils. Infiltration measurements have been converted to units of mm/day.

3.3.4

Hydraulic conductivity

Measurements of hydraulic conductivity were made in either the field or laboratory. Laboratory measurements were on either packed cores or on undisturbed cores taken from the soil profile. Field measurements were taken through the use of infiltration data and potential measurements made by tensiometers or piezometers. The results section of hydraulic conductivity have been divided into field and laboratory sections, with specific methods noted. Hydraulic conductivities have been reported in units of mm/day.

3.3.5

Moisture characteristics

Studies of moisture characteristics were varied with different interpretations on what value of suction best represents permanent wilting point and field capacity. There was also a large variation of units used to represent suctions. All measurements of suction were converted to units of kilopascals (kPa) which is equivalent to a kilonewton per square meter (kN/m2). Units commonly used were Bars and these were converted using 22

1Bar = 10 5 Pascals and pF which was converted by kPa = (10 pF/100)*9.8. It was assumed that 1500 kPa suctions were representative of permanent wilting point and 10 kPa suctions representative of field capacity. Measurements of field capacities and permanent wilting points were also taken using direct field measurements, moisture contents of the soil when plants showed moisture stress and moisture contents of the soil after irrigation. All moisture content measurements have been converted to a volumetric basis (m3/m3) using associated bulk density measurements. In the particular case of moisture contents at 10 and 1500 kPa suctions measured by Loveday et al. (1966) moisture contents have been converted to a volumetric basis using aggregate densities not bulk densities.

3.3.6

Electrical conductivities

Measurements of electrical conductivities have been restricted to those measured in a 1:5 water suspensions and are reported in mS/cm, equivalent to dS/m.

3.3.7

Exchangeable sodium percentage

Exchangeable sodium percentage (ESP) was not commonly reported in the literature, however in one particular report by Loveday et al. (1978) a number of measurements of exchangeable cations were undertaken. From these measurements exchangeable sodium percentage (ESP) was calculated from the following formula given in Dent and Young (1987). ESP = (exchangeable Na*100)/ CEC

where CEC is the cation exchange capacity and all measurements are in milliequivalents per litre. The data from the various reports found are reported in the following sections according to the grouping reported earlier. 23

4

SELF MULCHING CLAYS

4.1 Physical Composition

4.1.1.1 Particle size analysis

Loveday et al. (1966) conducted particle size analysis for two self-mulching clays, Wunnamurra and Yooroobla clay, on five different sites in the CIA. Particle size analysis was undertaken using normal mechanical analysis. Sodium tripolyphoshate was used as the dispersing agent and silt and clay contents were determined using a plummet balance. Three different depths were analysed, with these being 0-0.025, 0.025-0.1 and 0.2-0.3 m. Ranges of particle size distributions are shown in table 4.1.

Table 4-1 Ranges of particle size distribution for self-mulching clays (Loveday et al. 1966) P a rticle size CS % FS % Si % C%

0 -0 .0 2 5 m Low High 4 15 7 52

9 28 15 72

D epth (m) 0.025 -0.1 m Low High 3 15 8 51

9 27 16 72

0.2-0.3 m Low High 3 15 7 60

18 24 15 73

Loveday et al. (1978) also conducted particle size analysis on four MIA self-mulching clays, Wunnamurra, Gogeldrie, Coleambally and Yooroobla clays. Particle size analysis was undertaken using normal mechanical analysis methods. Sodium tripolyphosphate was used as the dispersing agent and silt and clay contents were determined using the plummet balance. Samples from seven sites were taken at two depths, 0-0.1 m and 0.20.3 m. Ranges of particle size distribution are shown in table 4.2.

24

Table 4-2 Ranges of particle size distribution for self-mulching clays (Loveday et al. (1978)

Particle s iz e CS % FS % Si % C %

D e p th (m ) 0 - 0 .1 m 0 .2 -0 .3 m Low H ig h Low H ig h 5 22 6 53

15 27 12 63

4 20 6 59

9 25 11 68

van der Lelij and Talsma (1977) also determined clay contents of self mulching clay soils and found a mean clay content of Yooroobla, Gogeldrie and Wunnamurra clays of 63 % at depths of 0.2-0.3 m during investigation of infiltration of self mulching clays. Christen (1994) also undertook particle size analysis on a Wunnamurra clay located in the MIA during investigations into mole drainage. Particle size analysis was carried out at depth intervals of 0.1-0.16 and 0.55-0.7 m. Results from the study are presented in table 4.3.

Stace et al. (1968) published particle size analysis data undertaken by Sleeman for a Yooroobla clay located in the MIA to a 1.8 m depth. Results from the study are shown in table 4.3.

Lattimore et al. (1994) also undertook particle size analysis on a Gogeldrie clay located in the MIA. Results from the particle size analysis are shown in figure 4.3. Smith (unpublished) also determined particle size analysis of a Wunnamurra clay at 0.1 m intervals to a 1 m depth. Results from the study are presented in table 4.3. Average particle size distribution with depth as calculated from all samples is shown in figure 4.1.

25

Table 4-3 Particle size analysis of self mulching clays Soil Type Yooroobla clay

CS % FS % Si % C%

0.025 8 23 11 59

5 16 10 69

6 16 10 69

Loveday 1966 (average 2)

CS % FS % Si % C%

8 23 12 57

9 20 9 62

Loveday 1978

Wunnamurra CS % clay FS % Si % C%

10 25 9 57

7 22 7 65

Loveday 1978 (average 3)

Coleambally clay

CS % FS % Si % C%

8 24 10 58

6 22 9 64

Loveday 1978 (average 2)

Yooroobla clay

CS % FS % Si % C%

6 26 10 58

5 24 10 61

Loveday 1978

Yooroobla clay

CS % FS % Si % C

7 6 6 20 19 19 6 4 4 55 62 63

Wunnamurra CS % clay FS % Si % C% Gogeldrie clay

5 17 10 68

Depth (m) Author 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.2 1.3 1.5 1.7 1.8 7 7 Loveday 22 19 1966 12 11 (average 3) 60 63

5 19 5 63

4 19 8 65

9 7 4 4 5 27 26 26 25 26 9 8 10 9 7 51 54 56 57 54

Wunnamurra CS % clay FS % Si % C%

8 7 7 9 8 5 6 7 6 6 27 22 21 22 21 22 22 22 22 22 15 14 15 14 15 18 17 15 16 17 50 57 57 55 55 55 55 56 55 55

Wunnamurra CS % clay FS % Si % C%

7 22 14 57

Gogeldrie Clay

8 20 12 60

CS % FS % Si % C%

6 15 10 70 8 18 8 66

Smith

Christen 1994

10 18 10 62

26

Stace 1968

Lattimore 1994

The bracketed average in the author column indicates how many sites were surveyed and results shown are the average of those sites for that particular soil type.

% 0

10

20

30

40

50

60

70

0 Average Coarse sand Average Fine sand

0.2 0.4 Depth (m)

0.6 0.8

Average Silt

1 1.2

Average Clay

1.4 1.6 1.8 2

Figure 4-1 Average particle size distribution with depth for self mulching clays

Analysis of all particle size distributions of all studies at depths between 0-0.1 m and 0.20.3 m has been undertaken. Statistical analysis of particle size distribution is listed between 0-0.1 m depths in table 4.4 and for 0.2-0.3 m depths in table 4.5. Figures 4.2 and 4.3 shown cumulative probability distributions of the particle size analysis in the 0-0.1 and 0.2-0.3 m depth layers.

Table 4-4 Statistical data relating to particle size analysis of self mulching clays in the 0-0.1 m layer

Average Lowest value Highest value Standard deviation Coeffiecient of variation M edian Geomean Number of samples

CS % 7 3 15 2 33 7 7 50

27

FS % 21 15 28 4 18 21 21 50

Si % 11 6 16 2 22 11 10 50

C% 61 50 72 6 9 61 61 50

Table 4-5 Statistical data relating to particle size analysis of self mulching clays in the 0.2-0.3 m layer

CS % 6 3 18 3 43 6 6 30

Probability of Exceedence

Ave ra ge va lue Low e st value H ig he st va lue Standard devia tio n C oe f f ic ie nt o f variatio n M e dia n Geomean N um be r of o f sam ple s

FS % 19 14 25 3 15 20 19 30

Si % 10 6 15 2 23 10 10 30

1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0

C % 65 59 73 4 6 64 65 30

Coarse Sand Fine Sand Silt Clay

0

10

20

30

40

50

60

70

80

%

Figure 4-2 Cumulative probability distribution of particle size of self mulching clays in the 0-0.1 m layer

28

Probability of exceedence

1 0.9 0.8 0.7

Coarse Sand

0.6

Fine Sand

0.5 0.4

Silt

0.3 0.2

Clay

0.1 0 0

10

20

30

40

50

60

70

80

%

Figure 4-3 Cumulative probability distribution of particle size of self mulching clays in the 0.2-0.3 m layer

4.1.1.2 Bulk density

Bulk density analysis for self-mulching clays has been undertaken by Loveday et al. (1978) for Wunnamurra, Gogeldrie, Coleambally and Yooroobla clays. The bulk density data was obtained from post irrigation sampling of soils from large area farms in the MIA. Seven different sites were used with 2 samples being taken at each site. Variation in bulk densities ranged from a low of 1240 kg/m3 at 0-0.1 m depth to 1620 kg/m3 at 0.60.8 m depth. Moisture contents at sampling were not given however the soil was sampled at a post irrigation stage.

Bulk density determinations were also carried out by Christen (1994) for a Wunnamurra clay at depths between 0.01 to 0.16 m and 0.55 to 0.7 m, bulk density was found to be 1400 kg/m3 and 1510 kg/m3 for the respective depths. McIntyre et al. (1976) also conducted bulk density determination at a depth greater than 0.8 m on a self mulching clay located in the MIA and found the bulk density at 3m to be 1850 kg/m3. 29

Loveday et al. (1966) also undertook aggregate density measurements on five sites consisting of Wunnamurra and Yooroobla clays. Aggregate densities were determined at 10 kPa and moisture contents reported in table 4.6.

Table 4-6 Bulk densities of self mulching clays S oil Type

0 .0 2 5

De p th (m ) 0 .4 0 .6

Au th o r

0 .1

0 .2

0 .3

0 .8

3

G o g e ld rie c la y

1245

1500

1495

1540

1570

1585

L o v e da y 1978

W u n n a m u rra c la y

1272

1402

1402

1476

1505

1517

(a v e ra ge 3 )

Co le a m b a lly c la y

1248

1440

1448

1488

1523

1540

(a v e ra ge 2 )

Y o o ro o b la c la y

1250

1350

1430

1520

1560

1530

W u n n a m u rra c la y

1400

1510

1650

S e lf m u lc h in g c la y

C hris te n 1994 1850

L o v e da y 1976

Y o o ro o b la c la y

{1 3 8 0 } {1 4 2 3 } {1 4 3 8 } {1 4 7 3 } [0 .3 4 9 ] [0 .3 7 1 ] [0 .3 9 5 ]

L o v e da y 1966 (a v e ra ge 3 )

W u n n a m u rra c la y

{1 2 6 8 } {1 3 0 5 } {1 3 7 8 } {1 3 6 3 } [0 .3 8 4 ] [0 .4 0 4 ] [0 .4 1 6 ]

(a v e ra ge 2 )

* Aggregate densities are shown in {}. Moisture contents are shown in [ ]

Statistical analysis of bulk densities of self mulching clays to a 0.8 m depth from results in the above studies are presented in table 4.7 and variation of bulk density with depth is shown in figure 4.4.

30

Table 4-7 Statistical analysis of bulk density data of self mulching clays (kg/m3) Depth (m) Average Lowest Highest Standard Coefficient Median value value value deviation of variation

1268 1427 1435 1490 1534 1537

0-0.1 0.1-0.2 0.2-0.3 0.3-0.4 0.4-0.6 0.6-0.8

1130 1350 1360 1450 1460 1470

1400 1510 1520 1530 1650 1620

79 59 52 25 48 42

6 4 4 2 3 3

Geomean No. of samples

1250 1430 1450 1490 1520 1530

1267 1430 1439 1491 1531 1533

14 13 13 13 15 13

B u lk D e n s it y ( k g / m 3 ) 1000 0

1100

1200

1300

1400

1500

1600

0 .1 0 .2

Depth (m)

0 .3 0 .4 0 .5 0 .6 0 .7 0 .8 0 .9

Figure 4-4 Bulk density variation with depth for self mulching clays

31

1700

1800

4.1.2

Water Movement

4.1.2.1 Infiltration studies

Infiltration studies have been carried out by van der Lelij and Talsma (1977) during prolonged ponding of soil at various sites in the MIA and CIA on Yooroobla, Wunnamurra and Gogeldrie clays. Infiltration rates during ponding were measured at 16 sites using large, buffered ring infiltrometers for each field. Measurements were restricted to infiltration between 1-16 weeks. Mean cumulative infiltration for the 16 sites varied from 12 mm at 2 weeks to 148 mm at 16 weeks, with the curve being slightly S shaped as shown in the figure 4.5. Mean infiltration rate near the end of ponding was calculated to be 1.4 mm/day.

Figure 4-5 Mean cumulative infiltration curves for clays taken from van der Lelij and Talsma (1977)

32

Talsma and Van der Lelij (1976) also carried out infiltration studies in the CIA on a Wunnamurra clay. Both small ring infiltrometers and large buffered infiltrometers were used to measure infiltration over a seven week period. Results from the three large ring infiltrometers had a median value of 3.7 mm/day between 50-125 days after ponding and for the small ring 1.6 mm/day. Mean infiltration rates over most of the ponding period were found to fluctuate considerably.

4.1.2.2 Hydraulic conductivity

Laboratory measurement

Studies on hydraulic conductivities of self mulching clays have been undertaken by Loveday et al. (1978) for four self mulching clays, Wunnamurra, Gogeldrie, Coleambally and Yooroobla. Ground soil was repacked into columns and saturated hydraulic conductivity measured with a falling head permeameter. Saturated hydraulic conductivities between 0-0.2 m depths have been measured at both 24 and 48 hr periods, 10 samples from seven different sites were taken in the study. Average values of recorded saturated hydraulic conductivitys are listed in table 4.8 along with a cumulative probability distribution of the data for both 24 and 48 hr time periods in figure 4.6.

Table 4-8 Statistical analysis of hydraulic conductivities of self mulching clays (mm/day) Time 24hr 48hr

Average value 42 37

Lowest value 24 24

Highest value 64 49

Standard deviation 18 14

Coefficien of variation 42 38

33

Median Geomean 38 44

38 34

No. of samples 10 10

Probability of exceedence

1

0.75

0.5

24 hr 48 hr

0.25

0 0

10

20

30

40

50

60

70

Hydraulic conductivty (mm/day)

Figure 4-6 Cumulative probability distribution of hydraulic conductivity

Field measurements

Hydraulic conductivity during prolonged ponding of self-mulching clays were undertaken by van der Lelij and Talsma (1977). Hydraulic conductivities were calculated from infiltration rates and potential gradients. Topsoil (0-0.45 m) unsaturated hydraulic conductivitys as calculated by infiltration and potential gradient measurements at 16 sites on self mulching clays gave an average hydraulic conductivity of 2.7 mm/day over a period of 10-100 days during ponding of the soil average potential gradient was found to be 0.73. Subsoil (1.2-1.5 m) saturated hydraulic conductivities for the study gave an average value of 1.11 mm/day at a potential gradient of 1.8, again calculated from infiltration measurements and potential gradients. Hydraulic conductivity at 100 days after ponding at one site on a self mulching clay was estimated to a 3 m depth from measurements of infiltration rate and potential gradient measured at the site. Results are presented in table 4.9, taken from van der Lelij and Talsma (1977).

34

Table 4-9 Hydraulic conductivity for self mulching clay during ponding (mm/day) D e p th in t e r v a l (m ) 0 -0 .5 0 .5 -1 1 -1 .5 1 .5 -2 2 -3 .0 5

G r a d ie n t

H y d r a u lic c o n d u c t iv it y (m m /d a y )

0 .0 6 0 .1 6 0 .9 4 1 .7 6 0 .8 6

2 0 .8 7 .8 1 .3 0 .7 1 .5

Hydraulic conductivities of a Wunnamurra clay, Talsma and Van der Lelij (1976), were also estimated using measurements of infiltration and piezometer readings. Hydraulic conductivity was found to vary between 0.5 and 9.7 mm/day measured at depths between 0.2 and 0.3 m with mean moisture potentials of –0.61 and –0.48 m at respective depths of 0.2 and 0.4 m, during a study of prolonged ponding of the soil on 16 sites. Hydraulic conductivity of a slurried top soil from the site was also conducted and ranged between 8.9 mm/day and 1.4 mm/day for respective depths of 0.02 m to 0.22 m.

4.1.3

Water Retention / Moisture Characteristic

Studies relating to moisture characteristics of self-mulching clay profiles have been undertaken by Loveday et al. (1977). Available water was calculated from the difference between capacity to hold water between 10 kPa and 1500 kPa suctions. The study was undertaken on five sites, which included Wunnamurra and Yooroobla clays. Available water for the five samples taken ranged between 0.08-0.10 m for the top 0.6 m with an average of 0.094 m of available water for the top 0.6 m of soil. Loveday et al. (1966) also undertook moisture characteristic studies on five sites in the CIA on Wunnamurra and Yooroobla clays. Moisture contents at 10 kPa and at 1500 kPa were determined, and the difference used as an approximation to available moisture. Clods were used for the 10 kPa determination and 1500 kPa moisture contents were determined using sieved soil in a pressure membrane. Available water was then estimated from the aggregate densities and 10 kPa and 1500 kPa moisture contents. The average available water for the five sites 35

was found to be 0.037 m for the top 0.3 m depth, with the highest recorded value being 0.046 m and the lowest 0.027 m for the top 0.3 m.

Field determinations of permanent wilting points and field capacity of a Wunnamurra clay have been undertaken by Loveday et al. (1977). Moisture contents were taken when the crop showed signs of moisture stress and then again after irrigation, figure 4.7. The difference between the two moisture contents was taken to represent the available water. 1500 kPa moisture content were also undertaken on the profiles, figure 4.7, taken from Loveday et al. (1977).

Figure 4-7 Volumetric moisture content profiles of a Wunnamurra clay

Measurements of moisture contents at 1500 kPa suctions were also made by Loveday et al. (1966) at depths of 0-0.025, 0.025-0.1 and 0.2-0.3 m. Volumetric water contents from these measurements were then calculated from aggregate densities and volumetric water contents. Volumetric water contents varied from 0.2-0.30 m3/m3 in the 0-0.025 m layer, 0.2-0.3 m3/m3 in the 0.025-0.1 m layer and 0.23-0.34 m3/m3 in the 0.2-0.3 m layer.

36

Stace et al. (1968) also compiled moisture content determinations at 1500 kPa suctions measured by Sleeman on a Yooroobla clay in the MIA. Results are shown in table 4-10. Loveday et al. (1978) also determined moisture contents at 1500 kPa suctions for Wunnamurra, Gogeldrie, Coleambally and Yooroobla clays located at seven sites in the MIA, Table 4.11 shows all the data found in this study.

Statistical data relating to all 1500 kPa moisture contents is shown in table 4.12 along with variation of moisture content with depth from all studies at 1500 kPa shown in figure 4.8.

Table 4-10 Ranges of 1500 kPa moisture contents (m3/m3) of self mulching clays, Loveday et al. (1978)

Volumetric water content

0-0.1 m Low High

0.2-0.3 m Low High

Depth (m) 0.3-0.4 m Low High

0.4-0.6 m Low High

0.231

0.264

0.268

0.294

0.288

0.323

37

0.335

0.352

0.6-0.8 m Low High

0.28

0.356

Table 4-11 1500 kPa volumetric moisture contents of self mulching clays 0.025 0.230

0.1 0.245

Depth (m) 0.3 0.4 0.266

0.282

0.284

0.303

Gogeldrie clay

0.242

0.268

0.283

0.296

0.291

Loveday 1978

Wunnamurra clay

0.259

0.296

0.320

0.330

0.339

(average 3)

Coleambally clay

0.267

0.295

0.298

0.315

0.323

(average 2)

Yooroobla clay

0.231

0.271

0.293

0.315

0.319

Yooroobla clay

0.23

0.23

0.25

Yooroobla clay

Wunnamurra clay

Author 0.6

0.8 Loveday 1966 (average 3) (average 2)

0.27

Stace 1968

Table 4-12 Statistical analysis of volumetric water contents at 1500 kPa Depth (m)

0.025 0.1 0.3 0.4 0.6 0.8

Average Lowest value value

0.251 0.256 0.283 0.301 0.315 0.325

0.207 0.229 0.230 0.250 0.270 0.280

Highest Standard Coefficient value deviation of variation

0.301 0.323 0.341 0.335 0.352 0.356

0.032 0.022 0.026 0.026 0.022 0.020

12.56 8.70 9.02 8.70 6.91 6.30

38

Median

0.251 0.255 0.281 0.299 0.312 0.326

Geomean

0.249 0.255 0.282 0.300 0.315 0.324

No. of samples

10 25 25 15 15 14

0

Moisture Content (m 3/m 3) 0.1 0.2 0.3

0.4

0

Depth (m)

0.2

0.4

0.6

0.8

Figure 4-8 Variation of volumetric water contents at 1500 kPa for self-mulching clays

Determinations of 10 kPa moisture contents were carried out by Loveday et al. (1966) at five sites on Wunnamurra and Yooroobla clays. Moisture contents at 10 kPa suctions were measured at depths of 0-0.025, 0.025-0.1 and 0.2-0.3 m in order to approximate the field capacity of the soils. Moisture contents ranged from 0.32-0.40 m3/m3 in the 0-0.025 m layer, 0.33-0.43 m3/m3 in the 0.025-0.1 m layer and 0.38-0.43 m3/m3. Stace et al. (1968) also compiled 10 kPa moisture content determinations measured by Sleeman in the MIA. Results from the study are shown in table 4.13.

39

Table 4-13 10 kPa volumetric moisture contents of self mulching clays Depth (m) 0.2

Soil type

0.025

0.1

Yooroobla clay

0.349

0.371

0.395

Loveday 1966 (average 3)

Wunnamurra clay

0.384

0.404

0.416

(average 2)

0.37

Yooroobla clay

0.33

0.3

0.39

0.6

Author

0.4

Stace 1968

Statistical data relating to 10 kPa moisture contents for all mentioned studies is shown in table 4.14 along with variation of volumetric moisture content at 10 kPa suction with soil depth, also shown in figure 4-9.

Table 4-14 Statistical analysis of volumetric water contents at 10 kPa Depth (m) Average Lowest value value 0.025 0.1 0.2 0.3 0.6

0.363 0.382 0.330 0.402 0.4

0.321 0.33 0.33 0.383

Highest Standard Coefficien value deviation of variation 0.397 0.429 0.33 0.427

0.0224 0.0257

6.19 6.73

0.0142

3.54

40

Median

0.363 0.383 0.33 0.403

Geomean No. of samples 0.362 0.382 0.33 0.402

10 11 1 11 1

0

0.1

Moisture Content (m3/m3) 0.2 0.3

0.4

0.5

0

Depth (m)

0.2

0.4

0.6

0.8

Figure 4-9 Variation of volumetric water contents at 10 kPa for self-mulching clays

4.1.4

Soil Salinity/Sodicity

Electrical conductivities for self mulching clay profiles have been undertaken by Loveday et al. (1978) for Wunnamurra, Yooroobla, Coleambally and Gogeldrie clays on seven sites in the MIA. Electrical conductivity analysis was undertaken in a 1:5 water suspension on ten samples from the sites at depths of 0.1, 0.2, 0.3, 0.4, 0.6 and 0.8 m. Loveday et al. (1983) also undertook electrical conductivity analysis on four self mulching clays to 0.8 m. Variation of electrical conductivity with depth is shown in figure 4.10.

41

EC (mS/cm) 0

0.5

1

1.5

2

2.5

0

Depth (m)

0.2

0.4

0.6

0.8

Figure 4-10 Electrical conductivity variation with depth for self mulching clays

Exchangeable sodium percentages (ESP) of self mulching clays have been calculated from exchangeable cation data recorded by Loveday et al. (1966) and Loveday et al. (1978). Loveday et al. (1966) determined exchangeable cations at profile depths of 00.025, 0.025-0.1 and 0.2-0.3 m on five sites of Yooroobla and Wunnamurra clays located in the CIA. ESP ranged from 0.08-0.6 % in the 0-0.025 m layer, 0.06-3.96 % in the 0.025-0.1 m layer and 0.48-3.96 % in the 0.2-0.3 m layer.

Loveday et al. (1978) also determined exchangeable cations for Wunnamurra, Yooroobla, Gogeldrie and Coleambally clays at seven sites in the MIA. ESP was calculated from these results at 0-0.1 and 0.2-0.3 m depths and ranged from 0.055-6.6 % in the 0-0.1 m layer and 1.03-15.6 % in the 0.2-0.3 m layer. ESP for the various soil type is shown in table 4.15.

Variation of ESP with depth for all the above mentioned studies is shown in figure 4.11 and statistical analysis of all studies in table 4.16.

42

Table 4-15 ESP for self-mulching clays Soil Type

0.025

Depth (m) 0.1

0.3

Author

Yooroobla clay

0.48

0.80

1.90

Loveday 1966 (average 3)

W unnam urra clay

0.26

0.92

2.51

Loveday 1966 (average 2)

W unnam urra clay

2.94

10.16

Loveday 1978 (average 3)

Gogeldrie clay

0.59

1.55

Loveday 1978

Yooroobla clay

4.40

3.72

Loveday 1978

Coleambally clay

2.24

4.73

Loveday 1978 (average 2)

ESP

Depth (m)

0

5

10

15

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4

Figure 4-11 ESP variation with depth for self mulching clays

43

20

25

Table 4-16 Analysis of ESP data of self mulching clays Depth Average (m) value 0.025 0.1 0.3

0.35 1.62 3.92

Lowest value 0.08 0.055 0.48

Highest Standard Coefficient Median Geomean No. of value deviation of variation samples 0.6 6.6 15.6

0.244 1.745 3.828

44

70.43 107.67 97.65

0.46 1.06 2.36

0.25 0.86 2.72

5 33 34

5

HARD SETTING CLAYS

5.1.1

Physical Composition

5.1.1.1 Particle size analysis

Loveday et al. (1978) conducted particle size analysis on a Riverina clay located in the MIA on a large area farm. The sampled site was in an annual pasture phase of the cereal (rice, wheat, barley) pasture rotation. Two determinations of particle size distribution were made at depths between 0-0.1 and 0.2-0.3 m, results from the study are shown in table 5.1. Loveday et al. (1983) also conducted particle size analysis on four hard setting clays located in the MIA and CIA. Individual names of the clays were not given however it was indicated that the particular clays were hard setting not self mulching. Particle size distributions for this study however were only conducted at 0-0.1 m depths. Particle size distribution ranged from 4-6 % coarse sand, 19- 32 % fine sand, 14-20 % silt and 36-55 % clay. Average values are given in table 5.1.

Table 5-1 Particle size distribution of hard setting clays Soil Type

Depth (m) 0.1 0.3

Hard setting clays

CS % FS % Si % C%

6 28 18 48

Riverina Clay

CS % FS % Si % C%

6 20 12 62

Author Loveday 1983 (average 4)

3 20 11 66

Loveday 1978

45

5.1.1.2 Bulk density

Bulk density analysis of hard setting clays has been undertaken by Loveday et al. (1978) at depths between 0-0.8 m at one site in the MIA on Riverina clay. Two replicates were taken post irrigation, with cores of 0.046 m diameter, Table 5.2.

Loveday and Scotter (1966) also undertook bulk density determinations on Riverina and Billabong clays at 3 sites in the MIA. Bulk densities were determined on 0.051 m diameter cores taken after the sites had been irrigated. Bulk densities ranged between 1290-1430 kg/m3 for 0-0.1 m depths and between 1510-1580 kg/m3 for 0.2-0.3 m depths, table 5.2.

Sharma (1971) also measured bulk densities of a Billabong clay at depths of 0.1, 0.3, 0.4 and 0.6 m. Bulk densities were determined from core samples of 0.048 m diameter which were collected three days after irrigation. Results from the study are shown in table 5.2. Variation of bulk density with depth for hard setting clays is shown in figure 5.1.

Table 5-2 Bulk densities of hard setting clays Soil Type

Depth (m) 0.3 0.4

Author

0.1

0.2

Riverina clay

1130

1270

Riverina clay

1320

1510

Loveday and Scotter

Billabong clay

1390

1565

(average 2)

Billabong clay

1510

1540

1350

1410

1580

46

0.6

0.8

1515

1480

1570

Loveday 1978

Sharma 1972

Bulk density 1000

1200

1400

1600

1800

0

Depth (m)

0.2 0.4 0.6 0.8

Figure 5-1 Variation of bulk density with depth for hard setting clays

5.1.1.3

Porosity

Loveday and Scotter (1966) have undertaken aggregate porosity measurements of a Billabong clay during an investigation into the emergence response of subterranean clover. Total porosity was determined on air-dried surface clods at the conclusion of the experiment and was found to be 0.26 m3/m3.

Sedgley (1962) also conducted porosity determinations on a Billabong clay. Porosity was calculated from E = (1-(Wod/ρsVod).100 where E is porosity, Wod the weight of oven dry soil, Vod the volume of oven dry soil and ρs the density of solid particles assumed to be 2.65. Volumes of soil samples were determined using the kerosene displacement technique. Seven samples from a 0.1-0.15 m layer gave a mean porosity of 0.343 m3/m3 with a standard deviation of 0.002.

47

5.1.2

Water Movement

5.1.2.1 Hydraulic conductivity

Laboratory measurements

Hydraulic conductivity measurements were undertaken by Sharma (1971) for a Billabong clay. The hydraulic conductivity of uniformly packed 1-2 mm air dry aggregates was measured with a falling head permeameter. The value of hydraulic conductivity was recorded at 4 hr intervals for a 24 hr period on aggregates from three depths in the profile. Mean hydraulic conductivitys at the end of the 24 hr period are shown in table 5.3.

Table 5-3 Hydraulic conductivity of a Billabong clay (Sharma 1972) Aggregate sample depths

0-0.075 0.075-0.15 0.15-0.3 0.3-0.45

Hydraulic conductivity after 24 hr (mm/day)

1440 29 4 6

Loveday et al. (1978) also undertook laboratory determinations of saturated hydraulic conductivity for a hardsetting clay, Riverina clay, on two samples taken at depths between 0-0.2 m in the Warrawidgee area of the MIA. Ground soil was packed into columns and saturated hydraulic conductivity measured with a falling head permeameter. Hydraulic conductivitys for the two samples at 24 hr periods were found to be 3.84 mm/day and at 48 hrs were 2.64 mm/day.

48

5.1.3

Water Retention/Moisture Characteristic

Determinations of available water for hard setting clays have been undertaken by Loveday et al. (1977) for a Riverina clay. Only one determination was made and the available water in the profile was found to be 0.058 m for the top 0.6 m of soil as calculated from the difference between post and pre irrigation samplings. Loveday and Scotter (1966) also undertook available water measurements on Riverina and Billabong clays located in the Warrawidgee area of the MIA. Available water for the top 0.4 m of soil was calculated from laboratory measurements of moisture contents of aggregates at 10 kPa (field capacity) and 1500 kPa (wilting point) from depths of 0-0.03, 0.03-0.1, 0.1-0.2, 0.2-0.3 and 0.3-0.4 m. Three determinations were made and the available water to a 0.4 m depth was found to be 0.05 and 0.054 m for the two sites on Billabong clays and 0.056 m for the Riverina clay.

Field determinations of moisture contents at permanent wilting points and field capacity of hard settings clays has been undertaken by Loveday et al. (1977) for two hardsetting clays, Billabong and Riverina. Moisture content determinations were obtained initially when the crops grown on the various sites showed moisture stress and again after irrigation. The difference between the two measured moisture curves of the soil was taken to represent the available water in the soil profile.

The results for the permanent wilting point moisture contents when plants showed initial signs of stress are shown in table 5.4, along with 1500 kPa moisture contents which were determined from laboratory measurements on the same Riverina clay profile. Loveday et al. (1978) also undertook laboratory determinations of 1500 kPa moisture contents of a Riverina clay located in the MIA. Two replicates were taken at the site and the mean 1500 kPa moisture content is shown in table 5.4. Moisture content profiles are shown in figure 5.2.

49

Table 5-4 Permanent wilting point volumetric moisture contents for hard setting clays Soil Type

0.05

0.075

Billabong clay

{0.1}

Riverina clay

{0.17} {0.18}

0.1 {0.21}

0.22

Riverina clay

0.15

Depth (m) 0.2 0.25 0.3

0.35

{0.26}

0.4

0.6

0.8

{0.29} {0.31}

{0.22}

{0.23}

{0.27}

{0.29}

0.275

0.28

0.29

0.3

0.258

Riverina clay

Author

0.301

0.32

Loveday 1977

0.349 0.295

Values determined from moisture contents in the field are shown in brackets.

Volumetric moisture content (m3/m3)

Depth (m)

0

0.1

0.2

0.3

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8

0.4

F ield 1500 kPa

Figure 5-2 Various volumetric moisture contents at permanent wilting point.

50

Loveday 1978

Field capacity determinations as found by Loveday et al. (1977) on Billabong and Riverina clays from moisture content sampling after irrigation are shown in table 5.5 and also graphically in figure 5.3.

Table 5-5 Volumetric moisture content measurements at field capacity for hard setting clays Soil Type

0.05

Billabong clay

0.31

Riverina clay

0.47

0.075

0.1

Depth (m) 0.15 0.25

0.33

0.32

0.42

0.38

0.3

Author 0.35

0.4

0.6

0.32

0.32

0.3

Loveday 1977

0.29

V olumetric moisture content (m3/m3) 0

0.1

0.2

0.3

0.4

0.5

0

Depth (m)

0.1 0.2 0.3 0.4 0.5 0.6

Figure 5-3 Variation of volumetric moisture contents at field capacity for hard setting clays

Soil moisture characteristic curves for a Billabong clay have also been constructed by Sharma (1971) over a range of water potentials, figure 5.4.

51

Figure 5-4 Soil moisture characteristic curve for a Billabong clay taken from Sharma (1971)

5.1.4

Soil Salinity/Sodicity

Electrical conductivity determinations for hard setting clay profiles have been undertaken by Loveday et al. (1978) on a Riverina clay and by Sharma (1966) for a Billabong clay, table 5.6. Measurements of exchangeable cations have been undertaken by Loveday et al. (1978) for a Riverina clay located in the MIA. ESP was calculated to be 8.2 % in the 00.1 m layer and 12.45 % in the 0.2-0.3 m layer.

Table 5-6 Electrical conductivities of hard setting clays Soil Type Billabong clay Riverina clay

0.075

0.1

0.246

0.15

0.2

Depth (m) 0.3 0.4

0.373

0.135

0.749

0.135

0.18

52

Author 0.45

0.6

1.173 2.613

0.255 0.315

1.49

0.8 Sharma 1971 Loveday 1978

6

TRANSITIONAL RED BROWN EARTHS

6.1.1

Physical Composition

6.1.1.1 Particle size analysis

Loveday et al. (1978) conducted particle size analysis on four transitional red brown earths, Willbriggie clay, Willbriggie clay loam, Marah loam, and Marah clay loam located on large area farms in the MIA. The studies were undertaken on 13 different sites with two samples being taken per site up to 20 m apart. Particle size analysis was undertaken using normal mechanical analysis. Sodium tripolyphoshate was used as the dispersing agent and silt and clay contents were determined using a plummet balance. Two different depths were analysed, being 0-0.1 and 0.2-0.3 m. Ranges of particle size distributions for transitional red brown earths measured in the study are shown in table 6.1.

Table 6-1 Ranges of particle size analysis for transitional red brown earths, Loveday et al. (1978) D e p th (m ) P a r t ic le s iz e CS % FS % Si % C %

Low

0 -0 . 1 H ig h 5 28 6 21

Low 24 55 17 57

0 .2 - 0 . 3 H ig h 2 17 4 51

15 30 12 73

Loveday et al. (1966) also conducted particle size analysis on three transitional red brown earths, Willbriggie clay loam, Willbriggie loam and Tuppal clay loam at 9 sites in the CIA. Particle size analysis was undertaken using the same method as specified above.

53

Samples from the nine sites were taken from three different depths, being 0-0.025, 0.0250.1 and 0.2-0.3 m, table 6.2.

Table 6-2 Ranges of particle size distribution for transitional red brown earths, Loveday et al. (1966). Depth (m) Particle size

0-0.025 Low

0.025-0.1

High

Low

0.2-0.3

High

Low

High

CS %

10

20

8

21

3

12

FS %

28

43

25

42

11

21

Si %

13

21

14

22

5

12

C%

19

46

17

49

61

76

Loveday et al. (1970) also undertook particle size determinations on Marah clay loam during an investigation into soil and cotton responses to tillage. Particle size analysis was undertaken at three depth ranges, being 0-0.05, 0.1-0.2 and 0.5-0.6 m, table 6.3. Blackwell et al. (1990) reported particle size analysis for a Mundiwa clay loam located in the Whitton area of the MIA, table 6.3. Clay contents of a Marah clay loam have also been determined by Jayawardane et al. (1984) to a 1 m depth from soil samples taken at Benerembah. Clay contents only were determined at 0.1 m depth intervals, in table 6.3. Kowalik et al. (1977) also determined only clay contents of a Marah clay loam at Benerembah in the MIA, table 6.3.

During investigations into mole drainage in the MIA, Christen (1994) also undertook particle size analysis on two transitional red brown earths, Morago and Mundiwa clay loams located in the Whitton area, table 6.3.

54

Soil analysis undertaken on bore holes on transitional red brown has also been carried out on a Willbriggie clay loam located in the CIA to depths of 3 m by Sleeman and Stanad (1983). Particularly high clay contents were found. Results from the analysis are presented in table 6.3.

Unpublished particle size analysis on two transitional red brown earth soils Willbriggie clay and Mundiwa clay loam was provided by Mr. David Smith, CSIRO Griffith. Particle size distributions were determined at 0.1 m intervals to a depth of 1.4 m for the Mundiwa clay loam profile and to a 1 m depth for the Willbriggie clay loam profile. Both profiles were located in the MIA and results are presented in table 6.3, with the Mundiwa clay loam analysis is an average of three replicates.

Average coarse sand, fine sand, silt and clay percentages from all of the above studies are shown graphically in figure 6.1.

Data analysis of particle size distributions in the 0-0.1 and 0.2-0.3 m layers for all transitional red brown earths profiles is shown in tables 6.4 and 6.5 respectively. Cumulative probability distributions for particle size distributions of transitional red brown earths has also been undertaken for depth ranges between 0-0.1 and 0.2-0.3 m are shown in figures 6.2 and 6.3 respectively.

55

0

20

% 40

60

80

0 0.5 Co arse sand

Depth (m)

1 1.5

Fine sand

2 Silt

2.5 Clay

3 3.5

Figure 6-1 Average particle size distribution with depth for transitional red brown earths

56

Table 6-3 Particle size distribution of transitional red brown earths Soil Type

Depth (m ) 0.025 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

Author 1

1.1 1.2 1.3 1.4 1.5 2.5

3

W illbriggie clay loam

CS % FS % Si % C%

15 36 18 31

14 34 18 34

6 15 7 71

Loveday 1966 (average 5)

Tuppal clay loam

CS % FS % Si % C%

15 32 16 37

14 30 17 39

7 16 10 68

(average 2)

W illbriggie loam

CS % FS % Si % C%

20 39 20 22

17 36 21 26

7 14 8 72

(average 2)

W illbriggie clay loam

CS % FS % Si % C%

14 36 11 38

7 23 6 65

Loveday 1978 (average 8)

W illbriggie clay

CS % FS % Si % C%

7 32 9 54

3 21 5 71

Marah clay loam

CS % FS % Si % C%

11 36 15 40

4 24 10 62

(average 2)

Marah loam

CS % FS % Si % C%

14 49 14 24

7 22 5 67

(average 2)

Marah clay loam

CS % FS % Si % C%

11 43 21 25

Mundiwa clay loam

Sand % Si % C%

60 24 17

Mundiwa clay loam

CS % FS % Si % C%

22 35 18 24

13 22 14 51

11 19 14 57

10 19 14 57

10 19 13 58

12 20 13 56

13 21 12 52

14 21 13 51

14 22 12 52

11 21 14 54

W illbriggie clay

CS % FS % Si % C%

14 44 11 31

9 33 11 47

7 28 10 55

7 29 10 55

8 32 9 51

9 30 10 51

9 30 12 50

9 27 14 50

10 32 12 46

10 29 14 47

Marah clay loam

C%

44

54

59

56

52

49

47

46

45

46

4 20 10 66

3 24 15 58

Loveday 1970

26 14 62

Blackw ell 1990

57

9 21 14 56

47

8 20 15 58

8 20 15 56

8 21 15 56

Smith unpublished

50

Jayaw ardane 1983

Marah clay loam

C%

38

60

54

47

Willbriggie clay loam

CS % FS % Si % C%

2 17 6 78

2 14 5 82

3 18 8 76

Marago clay loam

CS % FS % Si % C%

13 33 9 45

5 17 16 63

Mundiwa clay loam

CS % FS % Si % C%

21 39 24 17

8 12 15 65

3 20 3 79

45

49

3 20 5 78

3 20 10 72

50

4 20 11 70

Kowalik 1978

9 18 9 70

12 14 8 67

Sleeman and Stannard 1983 Christen 1994

Table 6-4 Statistical data relating to particle size analysis of transitional red brown earths for the 0-0.1 m layer Av erage v alue Lowest v alue Highest v alue Standard dev iation Coeffient of v ariation Median Geom ean No. of samples

CS % 14 5 24 4 27 14 13 73

FS % 36 25 55 5 15 36 35 73

Si % 16 6 22 4 25 16 15 73

C% 36 17 57 9 24 35 35 73

Table 6-5 Statistical data relating to particle size analysis of transitional red brown earths for the 0.2-0.3 m layer Average value Lowest value Highest value Standard deviation Coefficient of variation Median Geomean No. of samples

CS % 6 2 15 3 45 6 6 53

FS % 20 11 30 5 25 20 19 53

Si % 7 4 12 2 28 7 7 53

58

C% 67 51 76 6 8 68 67 53

Probability of exceedence

1

0.75

Coarse Sand Fine Sand

0.5

Silt 0.25 Clay 0 0

10

20

30

40

50

60

%

Figure 6-2 Cumulative probability distribution of particle size for transitional red brown earths in the 0-0.1 m layer

Probability of exceedence

1

0.75 Coarse Sand Fine Sand

0.5

Silt 0.25 Clay

0 0

20

40

60

80

%

Figure 6-3 Cumulative probability distribution of particle size for transitional red brown earths in the 0.2-0.3 m layer

59

6.1.1.2 Bulk density

Determinations of bulk density for transitional red brown earths has been undertaken by Loveday et al. (1978) for four transitional red brown earth soils, Willbriggie clay, Willbriggie clay loam, Marah loam and Marah clay loam at 15 sites in the MIA. Two samples were taken from each site and bulk densities were recorded to 0.8 m. Moisture contents were not given. Samples were obtained from post irrigation coring of sites in the annual pasture phase of the cereal (rice, wheat, and barley) - pasture rotation. Cores of 0.046 m diameter were used for sampling. Results from the study are presented in table 6.6.

Cai et al. (1994) also undertook bulk density determinations for a Mundiwa clay loam during the modeling of leaching and recharge. Bulk density was found to vary between 1370 kg/m3 at a 0-0.1 m depth and 1530 kg/m3 at a 1-2.4 m depth, table 6.6. Bulk density determinations have been undertaken to 4.6 m by Kowalik et al. (1978) on a Marah clay loam located at Benerembah in the MIA. Bulk density was found to vary between 1460 kg/m3 at 0.2-0.3 m, to 1800 kg/m3 at a depth of 4.6 m, table 7.6. Loveday et al. (1970) undertook bulk density determinations on Marah sandy clay loams and Marah clay at depths between 0-0.1 m and 0.2-0.3 m. Measurements were taken on 4 cores, each of 0.051 m diameter, after irrigation of the soil, table 7.6. During a preliminary sampling of the Whitton common Loveday et al. (1984) also measured bulk density of a Mundiwa clay loam at three profile depths on two sites. Five cores of 0.075 m diameter and 0.6 m long were used to determine the mean bulk density at each of the three depths. Mean bulk densities of the two sites at respective depths were then calculated, table 6.6. Determinations of bulk density were also undertaken by Christen (1994), table 6.6.

Talsma (1963) also determined bulk density measurements on a Tuppal clay located in the MIA during investigations into the control of saline groundwater. Results from the study are presented in table 6.6.

60

Statistical data relating to bulk densities of transitional red brown earths calculated from the previously mentioned studies is shown in table 6.7 the variation of bulk density with depth to 0.8 m for transitional red brown earths is shown in figure 6.4.

61

Table 6-6 Bulk densities of transitional red brown earths Soil Type

0.05 0.1

0.2

0.3

0.4

Depth (m) 0.6 0.8 1.1

Author 1.5

2

3.2

4.6

Willbriggie clay loam

1383 1497 1456 1506 1528 1536

Loveday 1978 (average 7)

Marah loam

1415 1558 1405 1448 1503 1540

(average 2)

Willbriggie clay

1230 1450 1375 1445 1505 1505

Marah clay loam

1363 1493 1475 1535 1578 1590

Mundiwa clay loam

1370 1430 1430 1450 1450 1500

1460

Marah clay loam

1630 1630 1620

Marah fine sandy clay loam

1460

1570

Marah clay

1380

1510

Mundiwa clay loam

1545 [0.25]

1430 [0.39]

1530

1680 1710 1860 1800

Cai 1994

Kowalik 1978

Loveday 1970 (average 2)

1455 [0.29]

Loveday 1984 (average 2) Christen 1994

Marago clay loam

1360

1460

Mundiwa clay loam

1360

1460

Tuppal clay

1440

1490

(average 2)

1470 1580 1590

62

Talsma 1963

B ulk D ensity (kg/m3)

1 00 0

1 20 0

1 40 0

1 60 0

1 80 0

2 00 0

0

Depth (m)

0.2

0.4

0.6

0.8

Figure 6-4 Variation of bulk density with depth for transitional red brown earths

Table 6-7 Statistical data relating to bulk densities of transitional red brown earths (kg/m3) Depth (m) 0.05 0.1 0.2 0.3 0.4 0.6 0.8 1.1 1.5 2 3.2 4.6

Average Lowest value value 1545 1369 1480 1444 1495 1528 1541 1599 1600 1710 1860 1800

1180 1310 1340 1370 1390 1440 1580 1530

Highest Standard Coefficient of Median Geomean No. of value deviation variation samples

1620 1630 1560 1630 1630 1640 1619 1680

93 75 63 68 64 56 20 75

7 5 4 5 4 4 1 5

63

1545 1375 1460 1450 1500 1540 1540 1599 1590

1545 1366 1478 1443 1493 1526 1540 1599 1599

1 30 31 30 30 31 31 3 3 1 1 1

6.1.1.3 Porosity

Porosity measurements of transitional red brown earths have been undertaken by McIntyre et al. (1982). Total porosity was estimated from the initial bulk density and corrected for measured final vertical swelling on two sites of Marah clay loam at Benerembah in the MIA after the site had been ponded, table 6.8.

Table 6-8 Porosity of Marah clay loam as found by McIntyre et al. (1982) D e p th (m ) 0 0 0 0 1 1 1 2 2 2 3 3 4

.1 .2 5 .5 5 .8 5 .5 .7 5 .1 .7 .3 .9 .5

P o r o s it y P lo t 1 P lo t 2 0 .5 0 .5 0 .4 8 0 .4 5 0 .4 2 0 .4 2 0 .4 2 0 .4 0 .4 0 .3 9 0 .3 8 0 .3 8 0 .3 8 0 .3 6 0 .3 7 0 .3 6 0 .3 4 0 .3 6

Loveday et al. (1966) also conducted determinations on total porosity and air filled porosity at nine sites in the CIA consisting of Willbriggie clay loam Willbriggie loam, and Tuppal clay loam. Measurements were made on core samples of 0.0372 and 0.0496 m diameter taken from a depth of between 0-0.1 m. Cores were taken at 24 hr and 48 hr periods after the plots had received 50mm of water, table 6.9.

64

Table 6-9 Porosity measurements of transitional red brown earths (m3/m3). Loveday et al. (1966) P o ro s ity

T o ta l p o ro s ity a f te r 2 4 h r A ir f ille d p o ro s ity a f te r 2 4 h r T o ta l p o ro s ity a f te r4 8 h r A ir f ille d p o ro s ity a f te r 4 8 h r

Range A v e ra g e

Low

Hig h

0 .5 1 0 .2 9 0 .5 0 0 .3 1

0 .4 4 0 .2 1 0 .2 9 0 .2 2

0 .6 0 .4 8 0 .5 9 0 .3 4

Total porosity determinations were also undertaken by Talsma (1963), the amount of water held at saturation was used to measure total porosity to a depth of 1.6 m, table 6.10.

Table 6-10 Total porosity of Tuppal clay (m3/m3), Talsma (1963) D e p th (m ) 0 0 0 0 1 1

-0 .2 .4 .7 -1 .3

T o t a l p o r o s it y 0 0 0 0 0 0

.2 -0 .4 5 5 -0 .7 -1 .3 -1 .6

.4 .4 .4 .4 .4 .4

3 3 5 1

Determinations of aggregate porosity have also been made by Loveday and Scotter (1966) for aggregates of Willbriggie clay loams. Total porosity was determined on airdry surface aggregates and was found to vary between 0.33-0.45 m3/m3.

65

6.1.2

Water Movement

6.1.2.1 Infiltration studies

McIntyre et al. (1982) conducted infiltration studies on a bare, ponded Marah clay loam at Benerembah in the MIA. Short-term infiltration measurements on the control were undertaken with three ring infiltrometers and also estimated from soil moisture changes during the ponding period. The control plot had a ploughed layer of heterogeneous material consisting of dry clods and finer soil. Short term infiltration on the control plot was found to vary dramatically, figure 6.5, the rather large shorter term infiltration recorded by the second infiltrometer was caused by water breakthrough to a crack.

Figure 6-5 Short-term infiltration during ponding on an initially dry soil

Rapid flow through infiltrometer two was caused by a water break through to a crack. However, the rapid flow ceased after 90 min and the infiltration was similar to the other infiltrometers after 90 min. Long term infiltration for the control plot during ponding was determined by measurements form two ring infiltrometers. Mean cumulative infiltration 66

was found to be 276mm for a 379-day period. Infiltration rates during ponding were found to be 5.3 mm/day during the first week of ponding, 1 mm/day from 2-5 weeks and 0.7 mm/day after a 16-week period.

van der Lelij and Talsma (1977) also undertook infiltration determinations on Willbriggie and Mundiwa clay loams in both the MIA and CIA irrigation areas. Studies of infiltration during prolonged ponding were made with 23 infiltrometers on several sites. The distribution of infiltration totals within transitional red brown earths as measured at the 23 sites is shown in figure 6.6 for a 2-16 week period from the start of permanent ponding.

Figure 6-6 Frequency distribution of infiltration totals measured over a 2-16 week period of permanent ponding on transitional red brown earths (van der Lelij and Talsma 1977)

Mean cumulative infiltration from the 23 infiltrometers over a 16-week period is shown in figure 6.7. Mean infiltration rate at the end of 16 weeks was found to be 0.25 mm/day.

67

Figure 6-7 Cumulative infiltration for transitional red brown earths as measured by van der Lelij and Talsma (1977)

Loveday et al. (1984) also undertook infiltration measurements on a Mundiwa clay loam at two sites in the Whittion area of the MIA. Two plots were ponded with water for a one-week period and then drained and covered for several days before sampling. Infiltration rates were determined using 0.3 m diameter rings at the surface and at surfaces exposed at 0.3 and 0.6 m depths after the rings had stood ponded for 24 hours. Four determinations of infiltration rate were made at the three depths for the two soil profiles. Mean infiltration rates are shown in table 6.11.

Table 6-11 Infiltration rates (mm/day) as measure by Loveday et al. (1984) Depth (m) surface 0.3 0.6

Infiltration rate (mm/day) 16.8 2.7 7.1

68

6.1.2.2 Hydraulic conductivity

Laboratory measurements

Laboratory determinations of saturated hydraulic conductivity on transitional red brown earth soils have been carried out by Loveday et al. (1978) at nine sites in the MIA, consisting of Willbriggie clay loams, Willbriggie clays, Marah clay loams and Marah loams. Saturated hydraulic conductivity was determined on ground soil repacked into columns taken from the sites at 0-0.2 m depths. Two samples were taken from each site and saturated hydraulic conductivity’s measured after 24 and 48-hour periods. Results from the study are presented in table 6.12 together with a cumulative probability distribution shown in figure 6.8.

Table 6-12 Statistical data relating to saturated hydraulic conductivities of transitional red brown earths as determined by Loveday et al. (1978) Time

24 hr 48 hr

Average Lowest value value

20 14

4 3

Highest value

65 57

Standard Coefficient Median deviation of variation

18 16

90 109

69

14 8

Geomean

14 9

No. of samples

12 12

Probability of exceedence

1

0.75

24hr

0.5

48hr

0.25

0 0

50 100 Hydraulic conductivity (mm/day)

150

Figure 6-8 Cumulative probability distributions of hydraulic conductivities of transitional red brown earths, after Loveday et al. (1978)

Loveday et al. (1970) also undertook hydraulic conductivity determinations on a Marah clay loam located in the MIA. Eight cores of 0.073 m diameter and 0.05 m long were taken from a 0.05-0.1 m depth on a Marah clay loam, which had been ploughed. Mean equilibrium hydraulic conductivity was found to be 166 mm/day with a standard error of 72 mm/day. Six core samples were also taken from a 0.3-0.35 m depth and mean hydraulic conductivity was found to be 5.52 mm/day with a standard error of 8.64 mm/day, highlighting the difference between surface and subsoil hydraulic conductivity after cultivation.

Saturated hydraulic conductivity determinations of a Mundiwa clay loam have been undertaken by Loveday et al. (1984) on two sites in the Whitton area. Two plots were ponded with water for a one week period and drained and covered for several days before sampling. Six cores of 0.075 m diameter and 0.05 m long were taken at three profile depths and results for the two plots are shown in table 6.13.

70

Table 6-13 Saturated hydraulic conductivity (mm/day) measured by Loveday et al. (1984) Depth (m)

0-0.05 0.3-0.35 0.6-0.65

Average

Plot 1 Low

1189