Sustainability of nutrient management in grain production systems of south-west Australia
Martin Harries
A B , Ken C. Flower B and Craig A. Scanlan C D
+ Author Affiliations
- Author Affiliations
A Department of Primary Industries and Regional Development, Government of Western Australia, 20 Gregory Street, Geraldton, WA 6530, Australia.
B UWA School of Agriculture and Environment and UWA Institute of Agriculture, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
C Department of Primary Industries and Regional Development, Government of Western Australia, 75 York Road, Northam, WA 6401, Australia.
D SoilsWest, UWA School of Agriculture and Environment, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
E Corresponding author. Email: martin.harries@dpird.wa.gov.au
Crop and Pasture Science 72(3) 197-212 https://doi.org/10.1071/CP20403
Submitted: 13 October 2020 Accepted: 18 January 2021 Published: 25 March 2021
Journal Compilation © CSIRO 2021 Open Access CC BY-NC
Abstract
Balancing nutrient inputs and exports is essential to maintaining soil fertility in rainfed crop and pasture farming systems. Soil nutrient balances of land used for crop and pasture production in the south-west of Western Australia were assessed through survey data comprising biophysical measurements and farm management records (2010–15) across 184 fields spanning 14 Mha. Key findings were that nitrogen (N) inputs via fertiliser or biological N2 fixation in 60% of fields, and potassium (K) inputs in 90% of fields, were inadequate to balance exports despite increases in fertiliser usage and adjustments to fertiliser inputs based on rotations. Phosphorus (P) and sulfur (S) balances were positive in most fields, with only 5% returning losses >5 kg P or 7 kg S/ha. Within each of the three agroecological zones of the survey, fields that had two legume crops (or pastures) in 5 years (i.e. 40% legumes) maintained a positive N balance. At the mean legume inclusion rate observed of 20% a positive partial N budget was still observed for the Northern Agricultural Region (NAR) of 2.8 kg N/ha.year, whereas balances were negative within the Central Agricultural Region (CAR) by 7.0 kg N/ha.year, and the Southern Agricultural Region (SAR) by 15.5 kg N/ha.year. Hence, N budgets in the CAR and SAR were negative by the amount of N removed in ~0.5 t wheat grain, and continuation of current practices in CAR and SAR fields will lead to declining soil fertility. Maintenance of N in the NAR was achieved by using amounts of fertiliser N similar to other regions while harvesting less grain. The ratio of fertiliser N to legume-fixed N added to the soil in the NAR was twice that of the other regions. Across all regions, the ratio of fertiliser N to legume-fixed N added to the soil averaged ~4.0:1, a major change from earlier estimates in this region of 1:20 under ley farming systems. The low contribution of legume N was due to the decline in legume inclusion rate (now 20%), the low legume content in pastures, particularly in the NAR, and improved harvest index of lupin (Lupinus angustifolius), the most frequently grown grain legume species. Further quantifications of the effects of changing farming systems on nutrient balances are required to assess the balances more accurately, thereby ensuring that soil fertility is maintained, especially because systems have altered towards more intensive cropping with reduced legume production.
Keywords: fertiliser, land use, nutrient budget, nitrogen, organic carbon, rotation, soil fertility.
References
ABARES (2018) Farm survey data 2018. Australian Bureau of Agricultural and Resource Economics, Canberra, ACT. Available at: www.agriculture.gov.au/abares/research-topics/surveys/farm-survey-data (accessed 8 October 2020)ABARES (2019) Agricultural commodities and trade data. Australian Bureau of Agricultural and Resource Economics, Canberra, ACT. Available at: https://www.agriculture.gov.au/abares/research-topics/agricultural-commodities/agricultural-commodities-trade-data (accessed 8 October 2020)
ABS (2016) Agricultural commodities, Australia and state/territory 2015–16. Cat. no. 7121. Australian Bureau of Statistics, Canberra, ACT. Available at: https://www.abs.gov.au/AUSSTATS/abs@.nsf/DetailsPage/7121.02015-16?OpenDocument (accessed 8 October 2020)
Alexandratos N, Bruinsma J (2012) World agriculture towards 2030/2050: the 2012 revision. ESA Working Paper. Food and Agricultural Organization of the United Nations, Rome.
Anderson G, Fillery I, Dolling P, Asseng S (1998a) Nitrogen and water flows under pasture–wheat and lupin–wheat rotations in deep sands in Western Australia. 1. Nitrogen fixation in legumes, net N mineralisation, and utilisation of soil-derived nitrogen. Australian Journal of Agricultural Research 49, 329–344.
| Nitrogen and water flows under pasture–wheat and lupin–wheat rotations in deep sands in Western Australia. 1. Nitrogen fixation in legumes, net N mineralisation, and utilisation of soil-derived nitrogen.Crossref | GoogleScholarGoogle Scholar |
Anderson G, Fillery I, Dunin F, Dolling P, Asseng S (1998b) Nitrogen and water flows under pasture–wheat and lupin–wheat rotations in deep sands in Western Australia. 2. Drainage and nitrate leaching. Australian Journal of Agricultural Research 49, 345–362.
| Nitrogen and water flows under pasture–wheat and lupin–wheat rotations in deep sands in Western Australia. 2. Drainage and nitrate leaching.Crossref | GoogleScholarGoogle Scholar |
Anderson GC, Peverill KI, Brennan RF (2013) Soil sulfur–crop response calibration relationships and criteria for field crops grown in Australia. Crop & Pasture Science 64, 523–530.
| Soil sulfur–crop response calibration relationships and criteria for field crops grown in Australia.Crossref | GoogleScholarGoogle Scholar |
Angus JF (2001) Nitrogen supply and demand in Australian agriculture. Australian Journal of Experimental Agriculture 41, 277–288.
| Nitrogen supply and demand in Australian agriculture.Crossref | GoogleScholarGoogle Scholar |
Angus J, Grace P (2017) Nitrogen balance in Australia and nitrogen use efficiency on Australian farms. Soil Research 55, 435–450.
| Nitrogen balance in Australia and nitrogen use efficiency on Australian farms.Crossref | GoogleScholarGoogle Scholar |
Angus JF, Peoples MB (2012) Nitrogen from Australian dryland pastures. Crop & Pasture Science 63, 746–758.
| Nitrogen from Australian dryland pastures.Crossref | GoogleScholarGoogle Scholar |
Angus J, Van Herwaarden A, Heenan D, Fischer R, Howe G (1998) The source of mineral nitrogen for cereals in south-eastern Australia. Australian Journal of Agricultural Research 49, 511–522.
| The source of mineral nitrogen for cereals in south-eastern Australia.Crossref | GoogleScholarGoogle Scholar |
Angus J, Bolger T, Kirkegaard J, Peoples M (2006) Nitrogen mineralisation in relation to previous crops and pastures. Australian Journal of Soil Research 44, 355–365.
| Nitrogen mineralisation in relation to previous crops and pastures.Crossref | GoogleScholarGoogle Scholar |
Angus J, Bell M, McBeath T, Scanlan C (2020) Nutrient-management challenges and opportunities in conservation agriculture. In ‘Australian agriculture in 2020: from conservation to automation in the search for sustainability’. (Eds J Pratley, J Kirkegaard) pp. 221–237. (Agronomy Australia and Charles Sturt University: Wagga Wagga, NSW)
Asseng S, Anderson G, Dunin F, Fillery I, Dolling P, Keating B (1998) Use of the APSIM wheat model to predict yield, drainage, and NO3-leaching for a deep sand. Australian Journal of Agricultural Research 49, 363–378.
| Use of the APSIM wheat model to predict yield, drainage, and NO3-leaching for a deep sand.Crossref | GoogleScholarGoogle Scholar |
Baldock G (2019) Nitrogen and organic matter decline: what is needed to fix it? In ‘Research updates’. Adelaide, S. Aust. (Ed. I Longson) (Grains Research and Development Corporation: Canberra, ACT) Available at: https://grdc.com.au/resources-and-publications/grdc-update-papers/tab-content/grdc-update-papers/2019/02/nitrogen-and-soil-organic-matter-decline-what-is-needed-to-fix-it (accessed 8 October 2020)
Baldock G, Macdonald L, Farrell M, Welti N, Monjardino M (2018) Nitrogen dynamics in modern cropping systems. In ‘Research updates’. Adelaide, S. Aust. (Ed. I Longson) (Grains Research and Development Corporation: Canberra, ACT) Available at: https://grdc.com.au/resources-and-publications/grdc-update-papers/tab-content/grdc-update-papers/2018/02/nitrogen-dynamics-in-modern-cropping-systems (accessed 8 October 2020)
Batlle-Aguilar J, Brovelli A, Porporato A, Barry DA (2011) Modelling soil carbon and nitrogen cycles during land use change. A review. Agronomy for Sustainable Development 31, 251–274.
| Modelling soil carbon and nitrogen cycles during land use change. A review.Crossref | GoogleScholarGoogle Scholar |
Bell M, Strong W, Elliott D, Walker C (2013a) Soil nitrogen–crop response calibration relationships and criteria for winter cereal crops grown in Australia. Crop & Pasture Science 64, 442–460.
| Soil nitrogen–crop response calibration relationships and criteria for winter cereal crops grown in Australia.Crossref | GoogleScholarGoogle Scholar |
Bell MJ, Moody PW, Anderson GC, Strong W (2013b) Soil phosphorus–crop response calibration relationships and criteria for oilseeds, grain legumes and summer cereal crops grown in Australia. Crop & Pasture Science 64, 499–513.
| Soil phosphorus–crop response calibration relationships and criteria for oilseeds, grain legumes and summer cereal crops grown in Australia.Crossref | GoogleScholarGoogle Scholar |
Bell R, Reuter D, Scott B, Sparrow L, Strong W, Chen W (2013c) Soil phosphorus–crop response calibration relationships and criteria for winter cereal crops grown in Australia. Crop & Pasture Science 64, 480–498.
| Soil phosphorus–crop response calibration relationships and criteria for winter cereal crops grown in Australia.Crossref | GoogleScholarGoogle Scholar |
Blair N, Crocker GJ (2000) Crop rotation effects on soil carbon and physical fertility of two Australian soils. Australian Journal of Soil Research 38, 71–84.
| Crop rotation effects on soil carbon and physical fertility of two Australian soils.Crossref | GoogleScholarGoogle Scholar |
Bolger T, Pate J, Unkovich M, Turner N (1995) Estimates of seasonal nitrogen fixation of annual subterranean clover-based pastures using the 15N natural abundance technique. Plant and Soil 175, 57–66.
| Estimates of seasonal nitrogen fixation of annual subterranean clover-based pastures using the 15N natural abundance technique.Crossref | GoogleScholarGoogle Scholar |
Bolland M (2011) Plant nutrition. In ‘Soil guide: a handbook for understanding and managing agricultural soils’. (Ed. G Moore) (Department of Agriculture, Western Australia: Perth, W. Aust.)
BOM (2018) State of the climate 2018. Bureau of Meteorology, Australian Government, Canberra, ACT. Available at: http://www.bom.gov.au/state-of-the-climate/State-of-the-Climate-2018.pdf (accessed 8 October 2020)
Bowden B, Burgess S (1993) Estimating soil nitrogen status—ready reckoners. Technote No. 6/93. Western Australian Department of Agriculture, South Perth, W. Aust.
Brennan RF, Bell MJ (2013) Soil potassium–crop response calibration relationships and criteria for field crops grown in Australia. Crop & Pasture Science 64, 514–522.
| Soil potassium–crop response calibration relationships and criteria for field crops grown in Australia.Crossref | GoogleScholarGoogle Scholar |
Brennan RF, Bolland MDA, Ramm RD (2013) Changes in chemical properties of sandy duplex soils in 11 paddocks over 21 years in the low rainfall cropping zone of southwestern Australia. Communications in Soil Science and Plant Analysis 44, 1885–1908.
| Changes in chemical properties of sandy duplex soils in 11 paddocks over 21 years in the low rainfall cropping zone of southwestern Australia.Crossref | GoogleScholarGoogle Scholar |
Bullock DG (1992) Crop rotation. Critical Reviews in Plant Sciences 11, 309–326.
| Crop rotation.Crossref | GoogleScholarGoogle Scholar |
Carmody P (2015) Farmer attitudes to break crops 2008 to 2014: what has changed? In ‘Crop updates’. Perth, W. Aust. (Ed. I Longson) (Grains Institute of Western Australia: Perth, W. Aust.) Available at: http://www.giwa.org.au/pdfs/CR_2015/SORT/W14_Carmody_Paul_Grower_attitudes_to_break_crops_Paper_CU15W14_.pdf (accessed 8/10/2020)
Cassman KG, Grassini P (2020) A global perspective on sustainable intensification research. Nature Sustainability 3, 262–268.
| A global perspective on sustainable intensification research.Crossref | GoogleScholarGoogle Scholar |
Chan KY, Conyers M, Li G, Helyar K, Poile G, Oates A, Barchia I (2011) Soil carbon dynamics under different cropping and pasture management in temperate Australia: results of three long-term experiments. Soil Research 49, 320–328.
| Soil carbon dynamics under different cropping and pasture management in temperate Australia: results of three long-term experiments.Crossref | GoogleScholarGoogle Scholar |
Congreves K, Grant B, Campbell C, Smith W, VandenBygaart A, Kröbel R, Lemke R, Desjardins R (2015) Measuring and modeling the long‐term impact of crop management on soil carbon sequestration in the semiarid Canadian prairies. Agronomy Journal 107, 1141–1154.
| Measuring and modeling the long‐term impact of crop management on soil carbon sequestration in the semiarid Canadian prairies.Crossref | GoogleScholarGoogle Scholar |
Craswell ET, Grote U, Henao J, Vlek PL (2004) Nutrient flows in agricultural production and international trade: ecological and policy issues. ZEF Discussion Papers on Development Policy. Center for Development Research, Bonn. Available at: https://www.researchgate.net/publication/23516447_Nutrient_Flows_In_Agricultural_Production_And_International_Trade_Ecological_And_Policy_Issues
Davis AS, Hill JD, Chase CA, Johanns AM, Liebman M (2012) Increasing cropping system diversity balances productivity, profitability and environmental health. PLoS One 7, e47149
| Increasing cropping system diversity balances productivity, profitability and environmental health.Crossref | GoogleScholarGoogle Scholar | 23071739PubMed |
Donald C, Williams C (1954) Fertility and productivity of a Podzolic soil as influenced by subterranean clover and superphosphate. Australian Journal of Agricultural Research 5, 664–687.
| Fertility and productivity of a Podzolic soil as influenced by subterranean clover and superphosphate.Crossref | GoogleScholarGoogle Scholar |
Drinkwater LE, Wagoner P, Sarrantonio M (1998) Legume-based cropping systems have reduced carbon and nitrogen losses. Nature 396, 262–265.
| Legume-based cropping systems have reduced carbon and nitrogen losses.Crossref | GoogleScholarGoogle Scholar |
Ellington A, Reeves T, Boundy K, Brooke H (1979) Increasing yield and soil fertility with pasture/wheat/grain-legume rotations and direct drilling. In ‘Proceedings 49th Congress Australian and New Zealand Association for the Advancement of Science’. Vol. 2, p. 509.
Evans J, McNeill A, Unkovich M, Fettell N, Heenan D (2001) Net nitrogen balances for cool-season grain legume crops and contributions to wheat nitrogen uptake: a review. Australian Journal of Experimental Agriculture 41, 347–359.
| Net nitrogen balances for cool-season grain legume crops and contributions to wheat nitrogen uptake: a review.Crossref | GoogleScholarGoogle Scholar |
FAO (2020) FAOSTAT data. Food and Agriculture Organization of the United Nations, Rome. Available at: http://www.fao.org/faostat/en/#data (accessed 8 October 2020)
Gartrell JW, Glencross RN (1968) Copper, zinc and molybdenum fertilizers for new land crops and pastures: 1969. Journal of the Department of Agriculture Western Australia 9, 517–521.
Gill G (1996) Management of herbicide resistant ryegrass in Western Australia: research and its adoption. In ‘Proceedings 11th Australian Weeds Conference’. 30 September 1996. Melbourne, Vic. pp. 542–545. (Weed Science Society of Victoria Inc.: Melbourne, Vic.)
Harries M, Anderson G, Hüberli D (2015) Crop sequences in Western Australia: what are they and are they sustainable? Findings of a four-year survey. Crop & Pasture Science 66, 634–647.
| Crop sequences in Western Australia: what are they and are they sustainable? Findings of a four-year survey.Crossref | GoogleScholarGoogle Scholar |
Harries M, Flower KC, Scanlan CA, Rose MT, Renton M (2020) Interactions between crop sequences, weed populations and herbicide use in Western Australian broadacre farms: findings of a six-year survey. Crop & Pasture Science 71, 491–505.
| Interactions between crop sequences, weed populations and herbicide use in Western Australian broadacre farms: findings of a six-year survey.Crossref | GoogleScholarGoogle Scholar |
Heap J (2000) Increasing Medicago resistance to soil residues of ALS-inhibiting herbicides. PhD thesis, Adelaide University, SA, Australia.
Helyar K, Cullis B, Furniss K, Kohn G, Taylor A (1997) Changes in the acidity and fertility of a red earth soil under wheat–annual pasture rotations. Australian Journal of Agricultural Research 48, 561–586.
| Changes in the acidity and fertility of a red earth soil under wheat–annual pasture rotations.Crossref | GoogleScholarGoogle Scholar |
Hoyle FC, Baldock JA, Murphy DV (2011) Soil organic carbon: role in rainfed farming systems. In ‘Rainfed farming systems’. (Eds P Tow, I Cooper, I Partridge, C Birch) pp. 339–361. (Springer: Dordrecht, The Netherlands)
Hoyle FC, O’Leary RA, Murphy DV (2016) Spatially governed climate factors dominate management in determining the quantity and distribution of soil organic carbon in dryland agricultural systems. Scientific Reports 6, 31468
| Spatially governed climate factors dominate management in determining the quantity and distribution of soil organic carbon in dryland agricultural systems.Crossref | GoogleScholarGoogle Scholar | 27530805PubMed |
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 |
Kirkby CA, Richardson AE, Wade LJ, Conyers M, Kirkegaard JA (2016) Inorganic nutrients increase humification efficiency and C-sequestration in an annually cropped soil. PLoS One 11, e0153698
| Inorganic nutrients increase humification efficiency and C-sequestration in an annually cropped soil.Crossref | GoogleScholarGoogle Scholar | 27144282PubMed |
Kirkegaard J, Christen O, Krupinsky J, Layzell D (2008) Break crop benefits in temperate wheat production. Field Crops Research 107, 185–195.
| Break crop benefits in temperate wheat production.Crossref | GoogleScholarGoogle Scholar |
Kirkegaard JA, Peoples MB, Angus JF, Unkovich MJ (2011) Diversity and evolution of rainfed farming systems in southern Australia. In ‘Rainfed farming systems’. (Eds P Tow, I Cooper, I Partridge, C Birch) pp. 715–754. (Springer: Dordrecht, The Netherlands)
Kumar S, Meena RS, Lal R, Yadav GS, Mitran T, Meena BL, Dotaniya ML, EL-Sabagh A (2018) Role of legumes in soil carbon sequestration. In ‘Legumes for soil health and sustainable management’. (Eds RS Meena, A Das, GS Yadav, R Lal) pp. 109–138. (Springer: Singapore)
Lacoste M (2017) Assessing the performance of ‘comparative agriculture’ methods to determine regional diversity in Australian farming systems: methodological relevance and application in the Western Australian wheatbelt. PhD thesis, University of Western Australia, Perth, WA, Australia.
Lassaletta L, Billen G, Grizzetti B, Anglade J, Garnier J (2014) 50 year trends in nitrogen use efficiency of world cropping systems: the relationship between yield and nitrogen input to cropland. Environmental Research Letters 9, 105011
| 50 year trends in nitrogen use efficiency of world cropping systems: the relationship between yield and nitrogen input to cropland.Crossref | GoogleScholarGoogle Scholar |
Liu J, You L, Amini M, Obersteiner M, Herrero M, Zehnder AJ, Yang H (2010) A high-resolution assessment on global nitrogen flows in cropland. Proceedings of the National Academy of Sciences of the United States of America 107, 8035–8040.
| A high-resolution assessment on global nitrogen flows in cropland.Crossref | GoogleScholarGoogle Scholar | 20385803PubMed |
Llewellyn R, D’emden F, Kuehne G (2012) Extensive use of no-tillage in grain growing regions of Australia. Field Crops Research 132, 204–212.
| Extensive use of no-tillage in grain growing regions of Australia.Crossref | GoogleScholarGoogle Scholar |
Loi A, Howieson JG, Nutt BJ, Carr SJ (2005) A second generation of annual pasture legumes and their potential for inclusion in Mediterranean-type farming systems. Animal Production Science 45, 289–299.
| A second generation of annual pasture legumes and their potential for inclusion in Mediterranean-type farming systems.Crossref | GoogleScholarGoogle Scholar |
Luo Z, Wang E, Sun OJ (2010) Soil carbon change and its responses to agricultural practices in Australian agro-ecosystems: a review and synthesis. Geoderma 155, 211–223.
| Soil carbon change and its responses to agricultural practices in Australian agro-ecosystems: a review and synthesis.Crossref | GoogleScholarGoogle Scholar |
Mayfield A (Ed.) (2008) ‘Grain legume handbook.’ (South Australian Department of Agriculture: Adelaide, S. Aust.)
McDonald G (1989) The contribution of nitrogen-fertilizer to the nitrogen nutrition of rainfed wheat crops in Australia: a review. Australian Journal of Experimental Agriculture 29, 455–481.
| The contribution of nitrogen-fertilizer to the nitrogen nutrition of rainfed wheat crops in Australia: a review.Crossref | GoogleScholarGoogle Scholar |
McNeill AM, Fillery IRP (2008) Field measurement of lupin belowground nitrogen accumulation and recovery in the subsequent cereal–soil system in a semi-arid Mediterranean-type climate. Plant and Soil 302, 297–316.
| Field measurement of lupin belowground nitrogen accumulation and recovery in the subsequent cereal–soil system in a semi-arid Mediterranean-type climate.Crossref | GoogleScholarGoogle Scholar |
Norton R (2009) Grain nutrient concentrations: report on a survey from 70 NVT wheat sites. International Plant Nutrition Institute, Australia and New Zealand 5, 44–46.
Norton R, Armstrong R, Latta R, Dart L, Dang V, Tang C, Walker C, Christie R (2007) Long term experiments: nutrient balances and lessons in the Wimmera & Mallee. In ‘Proceedings Long term Nutrient Management Workshop’. 4–5 June 2007. Adelaide, S. Aust. (Nutrient Management Systems: Brisbane, Qld)
Owen MJ, Walsh MJ, Llewellyn RS, Powles SB (2007) Widespread occurrence of multiple herbicide resistance in Western Australian annual ryegrass (Lolium rigidum) populations. Australian Journal of Agricultural Research 58, 711–718.
| Widespread occurrence of multiple herbicide resistance in Western Australian annual ryegrass (Lolium rigidum) populations.Crossref | GoogleScholarGoogle Scholar |
Owen MJ, Martinez NJ, Powles SB (2014) Multiple herbicide-resistant Lolium rigidum (annual ryegrass) now dominates across the Western Australian grain belt. Weed Research 54, 314–324.
| Multiple herbicide-resistant Lolium rigidum (annual ryegrass) now dominates across the Western Australian grain belt.Crossref | GoogleScholarGoogle Scholar |
Peoples M, Baldock J (2001) Nitrogen dynamics of pastures: nitrogen fixation inputs, the impact of legumes on soil nitrogen fertility, and the contributions of fixed nitrogen to Australian farming systems. Australian Journal of Experimental Agriculture 41, 327–346.
| Nitrogen dynamics of pastures: nitrogen fixation inputs, the impact of legumes on soil nitrogen fertility, and the contributions of fixed nitrogen to Australian farming systems.Crossref | GoogleScholarGoogle Scholar |
Peoples MB, Swan AD, Goward L, Kirkegaard JA, Hunt JR, Li GD, Schwenke GD, Herridge DF, Moodie M, Wilhelm N (2017) Soil mineral nitrogen benefits derived from legumes and comparisons of the apparent recovery of legume or fertiliser nitrogen by wheat. Soil Research 55, 600–615.
| Soil mineral nitrogen benefits derived from legumes and comparisons of the apparent recovery of legume or fertiliser nitrogen by wheat.Crossref | GoogleScholarGoogle Scholar |
Planfarm, Bankwest (2016) Planfarm Bankwest benchmarks 2015–16. Planfarm & Bankwest Agribusiness Centre, Perth, W. Aust. Available at: http://agric.firstsoftwaresolutions.com/attachments/1215/Planfarm%20Bankwest%20Benchmarks%202015-2016%20full-report.pdf (accessed 5 February 2020)
Planfarm, Bankwest (2018) Planfarm Bankwest benchmarks 2017–18. Planfarm Pty Ltd & Bankwest Agribusiness Centre, Perth, W. Aust. Available at: https://www.bankwest.com.au/content/dam/bankwest/documents/business/insights/planfarm-bankwest-benchmark-2018.pdf (accessed 8 October 2020)
Puckridge DW, French RJ (1983) The annual legume pasture in cereal–ley farming systems of southern Australia: a review. Agriculture, Ecosystems & Environment 9, 229–267.
| The annual legume pasture in cereal–ley farming systems of southern Australia: a review.Crossref | GoogleScholarGoogle Scholar |
Rayment GE, Lyons DJ (2011) ‘Soil chemical methods: Australasia.’ (CSIRO Publishing: Melbourne, Vic.)
Reeves TG (2020) Is sustainable intensification of cropping systems achievable. In ‘Research updates’. Melbourne. (Ed. I Longson) (Grain Research and Development Corporation: Canberra, ACT) Available at: https://grdc.com.au/resources-and-publications/grdc-update-papers/tab-content/grdc-update-papers/2020/02/is-sustainable-intensification-of-cropping-systems-achievable
Reuter D, Robinson JB (1997) ‘Plant analysis: an interpretation manual.’ (CSIRO Publishing: Melbourne, Vic.)
Roper MM, Gupta V, Murphy DV (2010) Tillage practices altered labile soil organic carbon and microbial function without affecting crop yields. Soil Research 48, 274–285.
| Tillage practices altered labile soil organic carbon and microbial function without affecting crop yields.Crossref | GoogleScholarGoogle Scholar |
Russell JS (1980) Crop sequences, crop pasture rotations and soil fertility. In ‘Proceedings 1st Australian Agronomy Conference’. Lawes, Qld. (Ed. IM Wood) (Australian Society of Agronomy) Available at: http://www.agronomyaustraliaproceedings.org/images/sampledata/1980/invited/crop-sequences/russell.pdf
Scanlon TT, Doncon G (2020) Rain, rain, gone away: decreased growing-season rainfall for the dryland cropping region of the south-west of Western Australia. Crop & Pasture Science 71, 128–133.
| Rain, rain, gone away: decreased growing-season rainfall for the dryland cropping region of the south-west of Western Australia.Crossref | GoogleScholarGoogle Scholar |
Seymour M, Kirkegaard JA, Peoples MB, White PF, French RJ (2012) Break-crop benefits to wheat in Western Australia – insights from over three decades of research. Crop & Pasture Science 63, 1–16.
| Break-crop benefits to wheat in Western Australia – insights from over three decades of research.Crossref | GoogleScholarGoogle Scholar |
Therneau, T, Atkinson, B, (2019) rpart: Recursive Partitioning and Regression Trees. R package version 4.1-15. The R Foundation, Vienna.
Unkovich M, Pate J, Hamblin J (1994) The nitrogen economy of broadacre lupin in southwest Australia. Australian Journal of Agricultural Research 45, 149–164.
| The nitrogen economy of broadacre lupin in southwest Australia.Crossref | GoogleScholarGoogle Scholar |
Unkovich MJ, Baldock J, Peoples MB (2010) Prospects and problems of simple linear models for estimating symbiotic N2 fixation by crop and pasture legumes. Plant and Soil 329, 75–89.
| Prospects and problems of simple linear models for estimating symbiotic N2 fixation by crop and pasture legumes.Crossref | GoogleScholarGoogle Scholar |
Walsh MJ, Powles SB (2007) Management strategies for herbicide-resistant weed populations in Australian dryland crop production systems. Weed Technology 21, 332–338.
| Management strategies for herbicide-resistant weed populations in Australian dryland crop production systems.Crossref | GoogleScholarGoogle Scholar |
Walsh MJ, Powles SB (2014) Management of herbicide resistance in wheat cropping systems: learning from the Australian experience. Pest Management Science 70, 1324–1328.
| Management of herbicide resistance in wheat cropping systems: learning from the Australian experience.Crossref | GoogleScholarGoogle Scholar | 24318955PubMed |
Walsh MJ, Owen MJ, Powles SB (2007) Frequency and distribution of herbicide resistance in Raphanus raphanistrum populations randomly collected across the Western Australian wheatbelt. Weed Research 47, 542–550.
| Frequency and distribution of herbicide resistance in Raphanus raphanistrum populations randomly collected across the Western Australian wheatbelt.Crossref | GoogleScholarGoogle Scholar |
Wang G, Huang Y, Wang E, Yu Y, Zhang W (2013) Modeling soil organic carbon change across Australian wheat growing areas, 1960–2010. PLoS One 8, e63324
| Modeling soil organic carbon change across Australian wheat growing areas, 1960–2010.Crossref | GoogleScholarGoogle Scholar | 24386270PubMed |
Weaver DM, Wong MT (2011) Scope to improve phosphorus (P) management and balance efficiency of crop and pasture soils with contrasting P status and buffering indices. Plant and Soil 349, 37–54.
| Scope to improve phosphorus (P) management and balance efficiency of crop and pasture soils with contrasting P status and buffering indices.Crossref | GoogleScholarGoogle Scholar |
