Surface soil acidity and fertility in the eastern Riverina and Western Slopes of southern New South Wales
B. J. Scott A B I , I. G. Fenton A C , A. G. Fanning D E , W. G. Schumann F G and L. J. C. Castleman HA NSW Department of Primary Industries, Agricultural Institute, PMB, Wagga Wagga, NSW 2650, Australia.
B Present address: EH Graham Centre for Agricultural Innovation (NSW Department of Primary Industries and Charles Sturt University), Faculty of Science and Agriculture, School of Agricultural and Veterinary Sciences, Charles Sturt University, Locked Bag 588, Wagga Wagga, NSW 2678, Australia.
C Present address: 160 Kincaid Street, Wagga Wagga, NSW 2650, Australia.
D South West Slopes Community Acid Soils Project, 1065 Waugh Road, Albury, NSW 2640, Australia.
E Present address: 9 Larissa Avenue, Ringwood, Vic. 3134, Australia.
F NSW Department of Primary Industries, PO Box 408, Queanbeyan, NSW 2620, Australia.
G Present address: Wine Policy Section, Department of Agriculture, Fisheries and Forestry, GPO Box 858, Canberra, ACT 2601, Australia.
H NSW Department of Primary Industries, 25 Anna Street, Urana, NSW 2645, Australia.
I Corresponding author. Email: bscott@csu.edu.au
Australian Journal of Experimental Agriculture 47(8) 949-964 https://doi.org/10.1071/EA05155x
Submitted: 1 June 2005 Accepted: 6 February 2007 Published: 16 July 2007
Abstract
This study, in southern New South Wales (NSW), examined the chemical properties of ~4700 surface soils in agricultural paddocks and recorded lime and gypsum inputs. The area was bounded approximately by Cootamundra in the north, the NSW/Victorian border in the south, extending to Tumbarumba in the east and to near Berrigan in the west. The long-term average annual rainfall ranged from ~420 mm in the west to a maximum of 1175 mm in the east. The data, collected between 1997 and 2003, were for the surface 20 cm of soil, in two 10-cm layers. The data were generated from a soil testing program conducted with farmers in the region. We grouped the soils into three zones based on a GPS location taken at the time of sampling. These zones were 1 (lower rainfall mixed farming), 2 (higher rainfall mixed farming) and 3 (long-term pasture). Acidic soils occurred across all three zones; however, the soils in zone 1 appeared to be less acidic than soils in the other two zones. We found that surface soils (0–10 cm) with soil pH in 1 : 5 soil : 0.01 mol/L calcium chloride (pHCa) ≤4.5 represented 27%, 57% and 54% for zones 1, 2 and 3, respectively. In addition, zone 1 had 74% of surface soils with a pHCa ≤ 5.0, and this was more acidic than previously reported. However, the surface soils in zone 1 had relatively low exchangeable aluminium (Alex) and had less acidic subsurface soils (10–20 cm), so that responses to lime application by pastures and crops may be less frequent or smaller than the surface soil pHCa alone may indicate. There was a higher frequency of acidic soils (pHCa ≤ 4.5) in the subsurface soils than in the surface soils in zones 2 (62 cf. 57%) and 3 (64 cf. 54%), suggesting that the acidity problem at this depth was a major problem. Low pHCa in the subsurface soil is known to be a constraint on crop yield. We found no evidence of the amendment of this soil depth when lime was applied and incorporated into the 0–10 cm depth, and economic amendment of acidity in the 10–20 cm depth remains unresolved.
Increased adoption of liming occurred in the late 1990s, and by 1997 the percentage of paddocks limed was 14.3%, 21.3% and 13.6% in zones 1 to 3, respectively. Soil pH buffering and long-term pHCa decline after liming were similar to rates reported in field experiments. The total quantities of lime applied were insufficient for soil amendment and maintenance of soil pHCa, particularly in the long-term pasture areas. The rate of soil acidification in the 0–20 cm depth in the average annual rainfall range of 525–625 mm was estimated to be 1.52 kmol H+/ha.year. This would require 76 kg lime/ha.year to neutralise. Sodic and saline soils occurred mainly in the lower rainfall cropping areas, and were more frequent in an area around the township of Lockhart. Half the gypsum applications were at low rates (≤0.5 t/ha), and were probably for sulfur application to canola. Some of the sodic soils were acidic (34% ≤ pHCa 4.5) so that the application of lime/gypsum mixes could be appropriate in the amendment of these soils. Soils in the pasture system had mean organic carbon content (OC%) of 2.42, compared to the cropping zones at 1.65 and 1.75%. OC% was related to annual average rainfall; the increase in OC% was 0.19% and 0.08% for each 100 mm of average annual rainfall for the surface and subsurface soil, respectively. A group of soils in the cropping areas had surface OC% ≤ 1.25% OC (zone 1, 12%; zone 2, 20%) and this could be the result of intensive cropping. Most soils (55–63%) were of moderate P status (P(Colwell), 21–60 µg/g). However, there was still a substantial group of soils (31–43%) of low P status (P ≤ 20 µg/g). Most surface soils in all zones (72–80%) were low to marginal in sulfur status (KCl 40, ≤10 mg S/kg). Sulfur deficiency has been identified in canola, and current practice in the cropping areas is for inputs of gypsum at low rates.
Additional keywords: ECEC, phosphorus, sodicity.
Acknowledgements
This research was funded by National Heritage Trust (NHT) through the South West Slopes Community Acid Soils Project, and by NSW Department of Primary Industries through Acid Soils Action Initiative. Soil analyses were conducted by Pivotest, now Incitec-Pivot.
We thank the chairman (Mr Peter Trescowthick) and committee of the South West Slopes Community Acid Soils group for making their data available to the authors. We thank the farmers (members of 27 Landcare groups) who cooperated in the South West Slopes Community Acid Soils Project and Acid Soil Action projects, and the local agronomists who contributed to the data collection and interpretation. We thank Sandra Maybury (NSW Dept Primary Industries), who entered the data for analysis, and Ian McGowen (Resource Information Unit, NSW Dept Primary Industries), who produced Fig. 1 and the underlying rainfall isohyets and rainfall outputs.
Anderson DL, Hendrick JG
(1983) Subsoil lime injector. Soil Science Society of America Journal 47, 337–339.
Blair GJ,
Chinoim N,
Lefroy RDB,
Anderson GC, Crocker GJ
(1991) A soil sulfur test for pastures and crops. Australian Journal of Soil Research 29, 619–626.
| Crossref | GoogleScholarGoogle Scholar |
Chan KY,
Heenan DP, So HB
(2003) Sequestration of carbon and changes in soil quality under conservation tillage on light-textured soils in Australia: a review. Australian Journal of Experimental Agriculture 43, 325–334.
| Crossref | GoogleScholarGoogle Scholar |
Chartres CJ,
Cumming RW,
Beattie JA,
Bowman GM, Wood JT
(1990) Acidification of soils on a transect from plains to slopes, south-western New South Wales. Australian Journal of Soil Research 28, 539–548.
| Crossref | GoogleScholarGoogle Scholar |
Colwell JD
(1963) The estimation of the phosphorus fertilizer requirements of wheat in southern New South Wales by soil analysis. Australian Journal of Experimental Agriculture and Animal Husbandry 3, 190–197.
| Crossref | GoogleScholarGoogle Scholar |
Conyers MK
(1986) The relationship between average annual rainfall and exchangeable aluminium in soils of south-eastern New South Wales. Australian Journal of Experimental Agriculture 26, 587–590.
| Crossref | GoogleScholarGoogle Scholar |
Conyers MK,
Scott BJ,
Fisher R, Lill L
(1995) Predicting the field performance of twelve commercial liming materials from southern Australia. Fertilizer Research 44(2), 151–161.
| Crossref | GoogleScholarGoogle Scholar |
Conyers MK,
Heenan DP,
Poile GJ,
Cullis BR, Helyar KR
(1996) Influence of dryland agricultural management practices on the acidification of a soil profile. Soil and Tillage Research 37, 127–141.
| Crossref | GoogleScholarGoogle Scholar |
Conyers MK,
Helyar KR, Poile GJ
(2000) pH buffering: the chemical response of acidic soils to added alkali. Soil Science 165, 560–566.
| Crossref | GoogleScholarGoogle Scholar |
Conyers MK,
Mullen CL,
Scott BJ,
Poile GJ, Braysher BD
(2003) Long term benefits of limestone applications to cereal crop yields in southern and central New South Wales. Australian Journal of Experimental Agriculture 43, 71–78.
| Crossref | GoogleScholarGoogle Scholar |
Dalal RC, Chan KY
(2001) Soil organic matter in rainfed cropping systems of the Australian cereal belt. Australian Journal of Soil Research 39, 435–464.
| Crossref | GoogleScholarGoogle Scholar |
Dolling PJ, Porter WM
(1994) Acidification rates in the central wheatbelt of Western Australia. 1. On a deep yellow sand. Australian Journal of Experimental Agriculture 34, 1155–1164.
| Crossref | GoogleScholarGoogle Scholar |
Dolling PJ,
Porter WM, Rowland IC
(1994) Acidification rates in the central wheatbelt of Western Australia. 2. On a sandy duplex soil. Australian Journal of Experimental Agriculture 34, 1165–1172.
| Crossref | GoogleScholarGoogle Scholar |
Ellington A
(1986) Effects of deep ripping, direct drilling, gypsum and lime on soils, wheat growth and yield. Soil and Tillage Research 8, 29–49.
| Crossref | GoogleScholarGoogle Scholar |
Gillman GP, Sumpter EA
(1986) Modification to the compulsive exchange method for measuring exchange characteristics of soils. Australian Journal of Soil Research 24, 61–66.
| Crossref | GoogleScholarGoogle Scholar |
Heenan DP,
Chan KY, Knight PG
(2004) Long-term impact of rotation, tillage and stubble management on the loss of soil organic carbon and nitrogen from a Chromic Luvisol. Soil and Tillage Research 76, 59–68.
| Crossref | GoogleScholarGoogle Scholar |
Helyar KR,
Cregan PD, Godyn D
(1990) Soil acidity in New South Wales – current pH values and estimates of acidification rates. Australian Journal of Soil Research 28, 523–537.
| Crossref | GoogleScholarGoogle Scholar |
Helyar KR,
Cullis BR,
Furniss K,
Kohn GD, Taylor AC
(1997) Changes in the acidity and fertility of red earth soil under wheat-annual pasture rotation. Australian Journal of Agricultural Research 48, 561–586.
| Crossref | GoogleScholarGoogle Scholar |
Hochman Z,
Osborne GJ,
Taylor PA, Cullis B
(1990) Factors contributing to reduced productivity of subterranean clover (Trifolium subterraneum L.) pastures on acidic soils. Australian Journal of Agricultural Research 41, 669–682.
| Crossref | GoogleScholarGoogle Scholar |
Jayawardane NS,
Barrs HD,
Muirhead WA,
Blackwell J,
Murray E, Kirchof G
(1995) Lime-slotting technique to ameliorate subsoil acidity in a clay soil. II. Effects on medic root growth, water extraction and yield. Australian Journal of Soil Research 33, 443–459.
| Crossref | GoogleScholarGoogle Scholar |
Noble AD,
Randall PJ, James TR
(1995) Evaluation of two coal-derived organic products in ameliorating surface and subsurface soil acidity. European Journal of Soil Science 46, 65–75.
| Crossref | GoogleScholarGoogle Scholar |
Osborne GJ,
Wright WA, Sykes J
(1978) Increasing soil acidity threatens farming system. Agricultural Gazette NSW 89, 21.
Scott BJ, Cullis BR
(1992) Subterranean clover pasture responses to lime application on the acid soils of southern New South Wales. Australian Journal of Experimental Agriculture 32, 1051–1059.
| Crossref | GoogleScholarGoogle Scholar |
Scott BJ,
Conyers MK,
Poile GJ, Cullis BR
(1997) Subsurface acidity and liming affect yield of cereals. Australian Journal of Agricultural Research 48, 843–854.
| Crossref | GoogleScholarGoogle Scholar |
Scott BJ,
Conyers MK,
Poile GJ, Cullis BR
(1999) Reacidification and reliming effects on soil properties and wheat yield. Australian Journal of Experimental Agriculture 39, 849–856.
| Crossref | GoogleScholarGoogle Scholar |
Scott BJ,
Ridley AM, Conyers MK
(2000) Management of soil acidity in long term pastures of south eastern Australia – a review. Australian Journal of Experimental Agriculture 40, 1173–1198.
| Crossref | GoogleScholarGoogle Scholar |
Smith CJ,
Goh KM,
Bond WJ, Freney JR
(1995) Effects of organic and inorganic calcium compounds on soil-solution pH and aluminium concentration. European Journal of Soil Science 46, 53–63.
| Crossref | GoogleScholarGoogle Scholar |
Walkley A, Black IA
(1934) An examination of the Degtjareff method for determining soil organic matter and a proposed modification of the chromic acid titration method. Soil Science 37, 29–38.
| Crossref | GoogleScholarGoogle Scholar |
Whitten MG,
Wong MTF, Rate AW
(2000) Amelioration of subsurface acidity in the south-west of Western Australia: downward movement and mass balance of surface incorporated lime after 2–15 years. Australian Journal of Agricultural Research 38, 711–728.
