Effects of gypsum and legumes on soil pH and soil organic C - Exp 2


Research organisatons
Funding source

Trial details

Researcher(s) Suzanne Holbery (ex (SARDI)
Roy Latta (ex (SARDI)
Glenn McDonald (UoA)
Pichu Rengasamy (ex (SARDI)
Ian Richter (SARDI)
Ehsan Tavakkoli (ex UoA)
Year(s) 2014
Contributor SARDI Minnipa Agricultural Centre
Trial location(s) Minnipa Agricultural Centre, SA
Effects of gypsum and legumes on soil pH and soil organic C - Exp 2 locations

To examine the effect of gypsum on soil pH and soil C and whether changes in soil pH could alter productivity of the following cereal crops.

Key messages

Applying gypsum can reduce soil pH and lower the concentration of dissolved organic carbon (C) to 30 cm depth within a year. Soils with pH > 9 will benefit most from gypsum. The solubilisation of soil organic C increased markedly at pH above 8.5. The availability of aluminium (Al) in soil increases at pH above 9. There was no significant effect of gypsum on the biomass or yields of crops within 2 years.

Lead research organisation University of Adelaide
Host research organisation SARDI Minnipa Agricultural Centre
Trial funding source DAWR 1203.014
Related program National Soil Carbon Program

The work was funded by the Australian Department of Agriculture through the Filling the Research Gap under National Soil Carbon Program

Other trial partners Not specified
Download the trial report to view additional trial information


Crop type Wheat
Treatment type(s)
  • Fertiliser: Rate
  • Soil amelioration: Type
Trial type Experimental
Trial design Replicated

Minnipa Agricultural Centre 2014

Sow date Not specified
Harvest date Not specified
Plot size 10m x 3m
Plot replication 3
Download the trial report to view additional method/treatment information

Download results

Trial results Table 1

# Variety
Treatment 1
Protein (%) pH 0-10cm (pH) pH 20-30cm (pH) Grain yield (t/ha) pH 10-20cm (pH)
1 Wheat:Mace Gypsum rate 0 t/ha 9.6 8.98 9.1 3.4 9.02
1 Wheat:Mace Gypsum rate 2.5 t/ha 9.5 8.79 8.94 3.13 8.89
2 Wheat:Mace Gypsum rate 5 t/ha 9.4 8.59 8.9 3.04 8.8
2 Wheat:Mace
3 Wheat:Mace
3 Wheat:Mace

Grain yield t/ha


pH 0-10cm pH


pH 10-20cm pH


pH 20-30cm pH


Protein %

Observed trial site soil information
Trial site soil testing
Not specified
Soil conditions
Trial site Soil texture
Minnipa Agricultural Centre, SA Calcareous red sandy loam
Derived trial site soil information
Australian Soil Classification Source: ASRIS
Trial site Soil order
Minnipa Agricultural Centre, SA Calcarosol
Soil Moisture Source: BOM/ANU
Average amount of water stored in the soil profile during the year, estimated by the OzWALD model-data fusion system.
Year Minnipa Agricultural Centre SA
2014 359.2mm
2013 293.9mm
2012 327.9mm
2011 370.8mm
2010 361.5mm
2009 368.6mm
2008 286.4mm
2007 291.5mm
2006 325.4mm
2005 292.1mm
2004 289.8mm
2003 302.0mm
2002 301.6mm
2001 343.8mm
2000 351.6mm
National soil grid Source: CSIRO/TERN
NOTE: National Soil Grid data is aggregated information for background information on the wider area
Actual soil values can vary significantly in a small area and the trial soil tests are the most relevant data where available

Soil properties



Minnipa Agricultural Centre SA 2014

Observed climate information

Rainfall trial gsr (mm) 290mm

Derived climate information

Minnipa Agricultural Centre SA


Some data on this site is sourced from the Bureau of Meteorology

SILO weather estimates sourced from https://www.longpaddock.qld.gov.au/silo/
Jeffrey, S.J., Carter, J.O., Moodie, K.B. and Beswick, A.R. (2001). Using spatial interpolation to construct a comprehensive archive of Australian climate data , Environmental Modelling and Software, Vol 16/4, pp 309-330. DOI: 10.1016/S1364-8152(01)00008-1.

Trial last modified: 10-09-2019 15:18pm AEST