Re-evaluating the contribution of summer fallow rain to wheat yield in southern Australia
J. R. Hunt A B and J. A. Kirkegaard A
+ Author Affiliations
- Author Affiliations
A CSIRO Sustainable Agriculture Flagship, PO Box 1600, Canberra, ACT 2600, Australia.
B Corresponding author. Email: james.hunt@csiro.au
Crop and Pasture Science 62(11) 915-929 https://doi.org/10.1071/CP11268
Submitted: 21 September 2011 Accepted: 24 October 2011 Published: 21 December 2011
Abstract
In southern Australia, summer fallow rain (SFR) has not traditionally been valued for winter crop production. Modern, higher yielding farming practices combined with a decade of below-average growing-season rainfall and a predicted increase in the proportion of summer rain under future climate patterns have stimulated a re-evaluation of this notion.
We used a widely validated crop simulation model (APSIM-Wheat) to quantify the potential value of SFR to wheat yield under contemporary farming practices using long-term climatic data at 37 locations throughout southern Australia.
The potential value of SFR was high, contributing on average 1.0 t/ha or 33% of water-limited attainable yield. Yield increases were due to both increased water use and increased water-use efficiency through higher harvest index. The contribution to yield varied significantly according to the rainfall distribution and soil type across sites. In central-west New South Wales, the equi-seasonal rainfall pattern, high soil water-holding capacity and variable spring rainfall resulted in SFR contributing up to 2.0 t/ha or 72% of mean simulated wheat yield. In contrast, in the north-western grain belt of Western Australia, SFR contributed as little as 0.1 t/ha or 3% of mean simulated yield due to strong Mediterranean rainfall pattern, low soil water-holding capacity and reliable growing-season rainfall. At all locations there was significant year-to-year variation in the simulated yield contribution of SFR. At a given site, soils with higher water-holding capacity in the surface tended to reduce summer fallow efficiency (proportion of summer rainfall stored at sowing) due to the failure of most summer rain to penetrate below the evaporation zone. Despite seasonal variability in yield contribution, interventions to preserve summer rainfall, such as strict summer weed control generated high return on investment (range 6–1328%; mean 733%). Risk of financial loss due to strict summer weed control varied across sites, with failure to achieve a return on investment occurring in 1–70% of years depending on location.
The proportion of annual rain falling during the summer fallow period in some locations has increased in the last 10 years and this forecast result of climate change is likely to increase the value of SFR to wheat production in the future.
Additional keywords: climate change, drought, fallow efficiency, water use, weeds.
References
Angus J, Good AJ (2004) Dryland cropping in Australia. In ‘Challenges and strategies for dryland agriculture. Vol. 32’. (Eds SC Rao, J Ryan) pp. 151–166. (Crop Science Society of America, American Society of Agronomy: Madison, WI)Bell LW, Kirkegaard JA, Swan A, Hunt JR, Huth NI, Fettell NA (2011) Impacts of soil damage by grazing livestock on crop productivity. Soil & Tillage Research 113, 19–29.
| Impacts of soil damage by grazing livestock on crop productivity.Crossref | GoogleScholarGoogle Scholar |
Browne C, Jones B (2008) How important is straw for yield of no-till crops on heavy soils in the low-rainfall southern Mallee? In ‘Global Issues Paddock Action. 14th Australian Agronomy Conference’. 21–25 September 2008, Adelaide, Australia. (Ed. M Unkovich) Available at: http://regional.org.au/au/asa/2008/concurrent/crop-agronomy/5832_brownec.htm#TopOfPag (accessed 19 July 2011).
Browne C, Hunt JR, Craig S, Whitbread A, Mowat D (2010) Improving winter crop productivity through increased capture and storage of summer fallow rain. In ‘Food Security from Sustainable Agriculture. 15th Australian Agronomy Conference’. 15–18 November 2010, Lincoln, New Zealand. (Eds H Dove, R Culvenor) Available at: www.regional.org.au/au/asa/2010/crop-production/soil-water/7005_brownec.htm (accessed 19 July 2011).
Carberry PS, Hochman Z, Hunt JR, Dalgliesh NP, McCown RL, Whish JPM, Robertson MJ, Foale MA, Poulton PL, van Rees H (2009) Re-inventing model-based decision support with Australian dryland farmers. 3. Relevance of APSIM to commercial crops. Crop & Pasture Science 60, 1044–1056.
| Re-inventing model-based decision support with Australian dryland farmers. 3. Relevance of APSIM to commercial crops.Crossref | GoogleScholarGoogle Scholar |
Cornish PS, Murray GM (1989) Low rainfall rarely limits wheat yields in southern New South Wales. Australian Journal of Experimental Agriculture 29, 77–83.
| Low rainfall rarely limits wheat yields in southern New South Wales.Crossref | GoogleScholarGoogle Scholar |
CSIRO and BOM (2007) ‘Climate change in Australia.’ (CSIRO: Canberra) Available at: www.climatechangeinaustralia.gov.au/resources.php (accessed 19 July 2011).
Dalgliesh NP, Foale MA, McCown RL (2009) Re-inventing model-based decision support with Australian dryland farmers 2. Pragmatic provision of soil information for field-specific simulation and for farmer decision making. Crop & Pasture Science 60, 1031–1043.
| Re-inventing model-based decision support with Australian dryland farmers 2. Pragmatic provision of soil information for field-specific simulation and for farmer decision making.Crossref | GoogleScholarGoogle Scholar |
Dolling PJ, Fillery IRP, Ward PR, Asseng S, Robertson MJ (2006) Consequences of rainfall during summer-autumn fallow on available soil water and subsequent drainage in annual-based cropping systems. Australian Journal of Agricultural Research 57, 281–296.
| Consequences of rainfall during summer-autumn fallow on available soil water and subsequent drainage in annual-based cropping systems.Crossref | GoogleScholarGoogle Scholar |
Felton W, Freebairn DM, Fettell NA, Thomas J (1987) Crop residue management. In ‘Tillage’. (Eds PS Cornish, JE Pratley) pp. 171–193. (Inkata Press: Melbourne)
Fischer RA (1987) Responses of soil and crop water relations to tillage. In ‘Tillage’. (Eds PS Cornish, JE Pratley) pp. 194–221. (Inkata Press: Melbourne)
Fischer RA, Armstrong JS (1990) Simulation of soil water storage and sowing day probabilities with fallow and no-fallow in southern New South Wales: II. Stochasticity and management tactics. Agricultural Systems 33, 241–255.
| Simulation of soil water storage and sowing day probabilities with fallow and no-fallow in southern New South Wales: II. Stochasticity and management tactics.Crossref | GoogleScholarGoogle Scholar |
Fischer RA, Armstrong JS, Stapper M (1990) Simulation of soil water storage and sowing day probabilities with fallow and no fallow in southern New South Wales: I. Model and long term mean effects. Agricultural Systems 33, 215–240.
| Simulation of soil water storage and sowing day probabilities with fallow and no fallow in southern New South Wales: I. Model and long term mean effects.Crossref | GoogleScholarGoogle Scholar |
Foley JL, Silburn DM (2002) Hydraulic properties of rain impact surface seals on three clay soils – influence of raindrop impact frequency and rainfall intensity during steady state. Australian Journal of Soil Research 40, 1069–1083.
| Hydraulic properties of rain impact surface seals on three clay soils – influence of raindrop impact frequency and rainfall intensity during steady state.Crossref | GoogleScholarGoogle Scholar |
Freebairn DM, Boughton WC (1981) Surface runoff experiments on the eastern Darling Downs. Australian Journal of Soil Research 19, 133–146.
| Surface runoff experiments on the eastern Darling Downs.Crossref | GoogleScholarGoogle Scholar |
Freebairn DM, Cornish PS, Anderson WK, Walker SR, Robinson JB, Beswick AR (2006) Management systems in climate regions of the world – Australia. In ‘Dryland agriculture. Vol. 23’. (Eds GA Peterson, PW Unger, WA Payne) pp. 837–878. (American Society of Agronomy, Inc., Crop Science Society of America, Inc., Soil Science Society of America, Inc.: Madison, WI)
French RJ, Schultz JE (1984) Water use efficiency of wheat in a Mediterranean-type environment: 1. The relationship between yield, water use and climate. Australian Journal of Agricultural Research 35, 743–764.
| Water use efficiency of wheat in a Mediterranean-type environment: 1. The relationship between yield, water use and climate.Crossref | GoogleScholarGoogle Scholar |
Fromm G, Grieger V (2002) The effect of summer weed management on subsequent grain yield and quality. In ‘13th Australian Weeds Conference’. 8–13 September 2002, Perth. (Eds H Spafford-Jacob, J Dodd, JH Moore) pp. 63–66. (Plant Protection Society of WA: Perth)
Gill BS, Jalota SK (1996) Evaporation from soil in relation to residue rate, mixing depth, soil texture and evaporativity. Soil Technology 8, 293–301.
| Evaporation from soil in relation to residue rate, mixing depth, soil texture and evaporativity.Crossref | GoogleScholarGoogle Scholar |
Golluscio RA, Sala OE, Lauenroth WK (1998) Differential use of large summer rainfall events by shrubs and grasses: a manipulative experiment in the Patagonian steppe. Oecologia 115, 17–25.
| Differential use of large summer rainfall events by shrubs and grasses: a manipulative experiment in the Patagonian steppe.Crossref | GoogleScholarGoogle Scholar |
GRDC (2007) ‘Investment plan (open and multi-stage tenders) 2008–2009.’ (GRDC: Canberra) Available at: www.grdc.com.au/uploads/documents/Investment%20Plan%20Open%20&%20Multistage%20Tender%20Final.pdf (accessed 19 July 2011).
Hatfield J, Sauer T, Prueger J (2001) Managing soil to achieve greater water use efficiency: a review. Agronomy Journal 93, 271–280.
| Managing soil to achieve greater water use efficiency: a review.Crossref | GoogleScholarGoogle Scholar |
Hillel D, Van Bavel CHM (1976) Simulation of profile water storage as related to soil hydraulic properties. Soil Science Society of America Journal 40, 807–815.
| Simulation of profile water storage as related to soil hydraulic properties.Crossref | GoogleScholarGoogle Scholar |
Hochman Z, Holzworth D, Hunt JR (2009a) Potential to improve on-farm wheat yield and WUE in Australia. Crop & Pasture Science 60, 708–716.
| Potential to improve on-farm wheat yield and WUE in Australia.Crossref | GoogleScholarGoogle Scholar |
Hochman Z, Van Rees H, Hochman Z, Van Rees H, Carberry PS, Hunt JR, McCown RL, Gartmann A, Holzworth D, Van Rees S, Dalgliesh NP, Long W, Peake AS, Poulton PL (2009b) Re-inventing model-based decision support with Australian dryland farmers: 4. Yield Prophet® helps farmers monitor and manage crops in a variable climate. Crop & Pasture Science 60, 1057–1070.
| Re-inventing model-based decision support with Australian dryland farmers: 4. Yield Prophet® helps farmers monitor and manage crops in a variable climate.Crossref | GoogleScholarGoogle Scholar |
Hunt JR (2006) The ecology of common heliotrope (Heliotropium europaeum L.) in a Mediterranean dry-land cropping system. PhD Thesis, The University of Melbourne, Australia.
Hunt JR, van Rees H, Hunt JR, van Rees H, Hochman Z, Carberry PS, Holzworth D, Dalgliesh NP, Brennan L, Poulton PL, van Rees S, Huth NI, Peake A (2006) Yield Prophet: an online crop simulation service. In ‘Ground-breaking stuff: 13th Australian Agronomy Conference’. 10–14 September 2006, Perth, W. Aust. (Eds NC Turner, T Acuna, RC Johnson) Available at: www.regional.org.au/au/asa/2006/concurrent/adoption/4645_huntj.htm (accessed 19 July 2011).
Hunt JR, Cousens RD, Knights SE (2009) Heliotropium europaeum only germinates following sufficient rainfall to allow reproduction. Journal of Arid Environments 73, 602–610.
| Heliotropium europaeum only germinates following sufficient rainfall to allow reproduction.Crossref | GoogleScholarGoogle Scholar |
Hunt JR, Swan A, Kirkegaard JA, Breust P, Peoples MB (2011) Do livestock reduce crop yields in conservation farming systems? In ‘5th World Congress on Conservation Agriculture’. 26–29 September 2011, Brisbane, Qld. pp. 382–383. (WCCA/FSD Local Organising Committee: Canberra)
Jeffrey SJ, Carter JO, Moodie KB, Beswick AR (2001) Using spatial interpolation to construct a comprehensive archive of Australian climate data. Environmental Modelling & Software 16, 309–330.
| Using spatial interpolation to construct a comprehensive archive of Australian climate data.Crossref | GoogleScholarGoogle Scholar |
Keating BA, Carberry PS, Hammer GL, Probert ME, Robertson MJ, Holzworth D, Huth NI, Hargreaves JNG, Meinke H, Hochman Z, McLean G, Verburg K, Snow V, Dimes JP, Silburn M, Wang E, Brown S, Bristow KL, Asseng S, Chapman S, McCown RL, Freebairn DM, Smith CJ (2003) An overview of APSIM, a model designed for farming systems simulation. European Journal of Agronomy 18, 267–288.
| An overview of APSIM, a model designed for farming systems simulation.Crossref | GoogleScholarGoogle Scholar |
Keen BA (1921) The evaporation of water from soil: II. Influence of soil type and manurial treatment. The Journal of Agricultural Science 11, 432–440.
| The evaporation of water from soil: II. Influence of soil type and manurial treatment.Crossref | GoogleScholarGoogle Scholar |
Kempenaar C, Groeneveld RMW, Uffing AJM (2006) Evaluation of Weed IT model 2006 MkII: spray volume and dose response tests. Note 418, Plant Research International B.V. Wageningen, October 2006.
Kirkegaard JA, Hunt JR (2010) Increasing productivity by matching farming system management and genotype in water-limited environments. Journal of Experimental Botany 61, 4129–4143.
| Increasing productivity by matching farming system management and genotype in water-limited environments.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXhtlShtLnL&md5=ce7a893bcc9799c027d3a4e09e152f60CAS |
Kirkegaard J, Lilley JM, Verburg K, Bond W (2007a) Fallow management, water storage and wheat yield in southern NSW. GRDC 2007 Adviser Update, Wagga Wagga. Available at: www.grdc.com.au/uploads/documents/cecc/CSO232/Attachment%204%20CSO232%20Final%20Report.pdf (accessed 20 July 2011).
Kirkegaard JA, Lilley JM, Howe GN, Graham JM (2007b) Impact of subsoil water use on wheat yield. Australian Journal of Agricultural Research 58, 303–315.
| Impact of subsoil water use on wheat yield.Crossref | GoogleScholarGoogle Scholar |
Lawson C, Sadras VO, Hooper P, McDonald G (2010) What influence does summer rainfall and stubble retention have on wheat production in southern farming systems? In ‘Food Security from Sustainable Agriculture: 15th Australian Agronomy Conference’. 15–18 November 2010, Lincoln, New Zealand. (Eds H Dove, R Culvenor) Available at: www.regional.org.au/au/asa/2010/crop-production/soil-water/7337_lawsoncs.htm (accessed 19 July 2011).
Lilley JM, Kirkegaard JA (2007) Seasonal variation in the value of subsoil water to wheat: simulation studies in southern New South Wales. Australian Journal of Agricultural Research 58, 1115–1128.
| Seasonal variation in the value of subsoil water to wheat: simulation studies in southern New South Wales.Crossref | GoogleScholarGoogle Scholar |
Lilley JM, Kirkegaard JA (2011) Benefits of increased soil exploration by wheat roots. Field Crops Research 122, 118–130.
| Benefits of increased soil exploration by wheat roots.Crossref | GoogleScholarGoogle Scholar |
Lilley JM, Kirkegaard J, Robertson MJ, Probert ME, Angus JF, Howe G (2003) Simulating crop and soil processes in crop sequences in southern NSW. In ‘Solutions for a Better Environment: 11th Australian Agronomy Conference’. 2–6 February 2003, Geelong. (Eds M Unkovich, GJ O’Leary) Available at: www.regional.org.au/au/asa/2003/c/12/lilley.htm (accessed 19 July 2011).
Lilley JM, Probert ME, Kirkegaard J (2004) Simulation of deep drainage under a 13-year crop sequence in southern NSW. In ‘4th International Crop Science Congress’. 26 September–1 October 2004, Brisbane, Australia. (Ed. RA Fischer) Available at: www.regional.org.au/au/asa/2004/poster/1/6/1306_lilleyjm.htm (accessed 19 July 2011).
Ludwig F, Milroy SP, Asseng S (2009) Impacts of recent climate change on wheat production systems in Western Australia. Climatic Change 92, 495–517.
| Impacts of recent climate change on wheat production systems in Western Australia.Crossref | GoogleScholarGoogle Scholar |
Meyer WS, Dugas WA, Barrs HD, Smith RCG, Fleetwood RJ (1990) Effects of soil type on soybean crop water-use in weighing lysimeters: 1. Evaporation. Irrigation Science 11, 69–75.
Moeller C, Asseng S, Berger J, Milroy SP (2009) Plant available soil water at sowing in Mediterranean environments – is it a useful criterion to aid nitrogen fertiliser and sowing decisions? Field Crops Research 114, 127–136.
| Plant available soil water at sowing in Mediterranean environments – is it a useful criterion to aid nitrogen fertiliser and sowing decisions?Crossref | GoogleScholarGoogle Scholar |
Mudge B, Whitbread A (2010) Making better decisions about crop rotations in low-rainfall environments: should stored moisture and the timing of the seeding opportunity influence this decision? In ‘Food Security from Sustainable Agriculture: 15th Australian Agronomy Conference’. 15–18 November 2010, Lincoln, New Zealand. (Eds H Dove, R Culvenor) Available at: www.regional.org.au/au/asa/2010/crop-production/sequence/6994_mudgeb.htm (accessed 11 July 2011).
Nicholls N (2006) Detecting and attributing Australian climate change: a review. Australian Meteorological Magazine 55, 199–211.
O’Leary GJ, Connor DJ (1997) Stubble retention and tillage in a semi-arid environment: 1. Soil water accumulation. Field Crops Research 52, 209–219.
| Stubble retention and tillage in a semi-arid environment: 1. Soil water accumulation.Crossref | GoogleScholarGoogle Scholar |
Oliver YM, Robertson MJ, Weeks C (2010) A new look at an old practice: benefits from soil water accumulation in long fallows under Mediterranean conditions. Agricultural Water Management 98, 291–300.
| A new look at an old practice: benefits from soil water accumulation in long fallows under Mediterranean conditions.Crossref | GoogleScholarGoogle Scholar |
Ortiz-Monasterio JI, Lobell DB (2007) Remote sensing assessment of regional yield losses due to sub-optimal planting dates and fallow period weed management. Field Crops Research 101, 80–87.
| Remote sensing assessment of regional yield losses due to sub-optimal planting dates and fallow period weed management.Crossref | GoogleScholarGoogle Scholar |
Osten V, Hashem A, Koetz E, Lemerle D, Pathan S, Wright G (2006) Impacts of summer fallow weeds on soil nitrogen and wheat in the southern, western and northern Australian grain regions. In ‘15th Australian Weeds Conference: Managing Weeds in a Changing Climate’. 24–28 September 2006, Adelaide. (Eds C Preston, JH Watts, ND Crossman) pp. 395–398. (Weed Management Society of South Australia Inc.: Adelaide)
Passioura JB, Angus J (2010) Improving productivity of crops in water-limited environments. Advances in Agronomy 106, 37–75.
| Improving productivity of crops in water-limited environments.Crossref | GoogleScholarGoogle Scholar |
Pook M, Lisson S, Risbey J, Ummenhofer CC, McIntosh P, Rebbeck M (2009) The autumn break for cropping in southeast Australia: trends, synoptic influences and impacts on wheat yield. International Journal of Climatology 29, 2012–2026.
| The autumn break for cropping in southeast Australia: trends, synoptic influences and impacts on wheat yield.Crossref | GoogleScholarGoogle Scholar |
Priestley C, Taylor RJ (1972) Assessment of surface heat flux and evaporation using large-scale parameters. Monthly Weather Review 100, 81–92.
| Assessment of surface heat flux and evaporation using large-scale parameters.Crossref | GoogleScholarGoogle Scholar |
Rallison R (1980) Origin and evolution of the SCS runoff equation. In ‘Proceedings of the Symposium on Watershed Management’. pp. 912–924. (American Society of Civil Engineering: Boise, ID)
Rebetzke GJ, Richards RA, Fettell NA, Long M, Condon AG, Forrester RI, Botwright TL (2007) Genotypic increases in coleoptile length improves stand establishment, vigour and grain yield of deep-sown wheat. Field Crops Research 100, 10–23.
| Genotypic increases in coleoptile length improves stand establishment, vigour and grain yield of deep-sown wheat.Crossref | GoogleScholarGoogle Scholar |
Ridge PE (1986) A review of long fallows for dryland wheat production in southern Australia. The Journal of the Australian Institute of Agricultural Science 52, 37–44.
Sadras V, Rodriguez D (2007) The limit to wheat water-use efficiency in eastern Australia. II. Influence of rainfall patterns. Australian Journal of Agricultural Research 58, 657–669.
| The limit to wheat water-use efficiency in eastern Australia. II. Influence of rainfall patterns.Crossref | GoogleScholarGoogle Scholar |
Schultz JE (1972) The effect of surface treatments on soil water storage and yield of wheat. Australian Journal of Experimental Agriculture and Animal Husbandry 12, 299–305.
| The effect of surface treatments on soil water storage and yield of wheat.Crossref | GoogleScholarGoogle Scholar |
Scott BJ, Eberbach PL, Evans J, Wade LJ (2010) ‘EH Graham Centre Monograph No. 1: stubble retention in cropping systems in Southern Australia: benefits and challenges.’ (Industry and Investment NSW: Wagga Wagga) Available at: www.csu.edu.au/research/grahamcentre/ (accessed 19 July 2011).
Smith IN, McIntosh P, Ansell TJ, Reason CJC, McInnes K (2000) Southwest Western Australian winter rainfall and its association with Indian Ocean climate variability. International Journal of Climatology 20, 1913–1930.
| Southwest Western Australian winter rainfall and its association with Indian Ocean climate variability.Crossref | GoogleScholarGoogle Scholar |
Verburg K, Bond W (2003) ‘Use of APSIM to simulate water balances of dryland farming systems in south eastern Australia.’ (CSIRO Land and Water: Canberra) Available at: www.clw.csiro.au/publications/technical2003/tr50-03.pdf (accessed 19 July 2011).
Verburg K, Bond W, Hunt JR (2010) Variable soil water accumulation under fallow management: explanation using a pulse paradigm. In ‘Food Security from Sustainable Agriculture: 15th Agronomy Conference’. 15–18 November 2010, Lincoln, New Zealand. (Eds H Dove, R Culvenor) Available at: www.regional.org.au/au/asa/2010/crop-production/soil-water/7177_verburgk.htm (accessed 11 July 2011).
Verburg K, Bond W, Hunt JR (2011) Fallow management in dryland agriculture: explaining soil water accumulation using a pulse paradigm. Field Crops Research (in press).
Verdon-Kidd DC, Kiem AS (2009) Nature and causes of protracted droughts in southeast Australia: comparison between the Federation, WWII, and Big Dry droughts. Geophysical Research Letters 36, L22707
| Nature and causes of protracted droughts in southeast Australia: comparison between the Federation, WWII, and Big Dry droughts.Crossref | GoogleScholarGoogle Scholar |
Ward P, Whisson K, Micin S, Zeelenberg D, Milroy S (2009) The impact of wheat stubble on evaporation from a sandy soil. Crop & Pasture Science 60, 730–737.
| The impact of wheat stubble on evaporation from a sandy soil.Crossref | GoogleScholarGoogle Scholar |
