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Graham Schwenke

Research interests

  • Soil nitrogen cycling in productive agriculture
  • Gaseous losses of ammonia and nitrous oxide from cropping soils
  • Soil organic matter management in farming systems and post-mining environments
  • Sustainable management of cropping soils
  • Impacts of agricultural inputs on soil biology
  • Subsoil constraints to dryland cropping systems
  • Crop nutrition management
  • Soil health
  • Legume nitrogen fixation


Graeme Schwenke is a senior research scientist based at the Tamworth Agricultural Institute, working in a range of soils-related research and extension activities focused on the northwest NSW cropping region.

He joined NSW Agriculture* in 1994 as a project officer to investigate the effects of zero-tillage and pulse legume rotations on soil organic matter dynamics in northern NSW cropping systems, and in northern Pakistan.

Subsequent research areas have included: measuring nitrogen fixation in pulse crops; emerging issues for crop nutrition for high-yielding cropping systems; management of subsoil constraints to crop production; effects of agricultural inputs on soil biology; understanding risk factors affecting nitrogen volatilisation from local soils; and soil health training for farmers; managing nitrous oxide emissions from dryland and irrigated cropping; and improving fertiliser nitrogen use efficiency in irrigated cotton.

Graeme has over 20 years scientific research experience in Australia, plus significant overseas project experience in Pakistan and Nepal. Graeme has written or contributed to many scientific journal papers, conference papers, magazine articles, workshop training materials and project results books.

*NSW Department of Primary Industries was formed on July 1, 2004 through an amalgamation of NSW Agriculture, NSW Fisheries, State Forests of NSW, and the NSW Department of Mineral Resources.


B.Agr.Sc. (Hons 1) – major in Land Resource Management. University of Queensland
Ph.D – Soil organic matter dynamics in the post-mining landscape at Weipa, north Queensland. University of Queensland.

Current projects

  • “More profit from nitrogen - enhancing nutrient use efficiency in cotton” (Cotton Research and Development Corporation and Australian Department of Agriculture)
  • “Determining optimum nitrogen strategies for abatement of emissions for different irrigated cotton systems” (Cotton Research and Development Corporation and Australian Department of Agriculture)
  • “ Deep placement of nutrients” (The University of Queensland, and Grains Research and Development Corporation)

Recent publications

Schwenke GD, Herridge D, Haigh BM, Rowlings D, Scheer C, McMullen G (2016) Greenhouse gas (N2O and CH4) fluxes under nitrogen-fertilised dryland wheat and barley on sub-tropical Vertosols: risk, rainfall, and alternatives. Soil Research 54(5), 634-650.

Schwenke GD, Haigh BM (2016) The interaction of seasonal rainfall and nitrogen fertiliser rate on soil N2O emission, total N loss and crop yield of dryland sorghum and sunflower grown on sub-tropical Vertosols. Soil Research 54(5), 604-618.

Mielenz H, Thorburn P, Harris R, Officer S, Li G, Schwenke G, Grace P (2016) Nitrous oxide emissions from grain production systems across a wide range of environmental conditions in eastern Australia. Soil Research 54(5), 659-674.

Li G, Conyers M, Schwenke G, Hayes R, Liu D, Lowrie A, Poile G, Oates A, Lowrie R (2016) Tillage does not increase nitrous oxide emissions under dryland canola (Brassica napus L.) in a semi-arid environment of south-eastern Australia. Soil Research 54(5), 512-522.

Rabbi SMF, Tighe M, Delgado-Baquerizo M, Cowie A, Robertson F, Dalal R, Page K, Crawford D, Wilson BR, Schwenke G, McLeod M, Badgery W, Dang YP, Bell M, O’Leary G, Liu DL, Baldock J (2015) Climate and soil properties limit the positive effects of land use reversion on carbon storage in Eastern Australia. Scientific Reports 5, 17866.

Schwenke GD, Simpfendorfer SR, Collard BCY (2015) Confirmation of chloride deficiency as the cause of leaf spotting in durum wheat grown in the Australian northern grains region. Crop and Pasture Science 66(2), 122-134.

Schwenke GD, Herridge DF, Scheer C, Rowlings DW, Haigh BM, McMullen KG (2015) Soil N2O emissions under N2-fixing legumes and N-fertilised canola: A reappraisal of emissions factor calculations. Agriculture, Ecosystems & Environment 202(1), 232-242.

Schwenke GD, Manning W, Haigh BM (2014) Ammonia volatilisation from nitrogen fertilisers surface-applied to bare fallows, wheat crops and perennial-grass-based pastures on Vertosols. Soil Research 52(8), 805-821.

Rabbi SMF, Tighe M, Cowie A, Wilson BR, Schwenke G, McLeod M, Badgery W, Baldock J (2014) The relationships between land uses, soil management practices, and soil carbon fractions in South Eastern Australia. Agriculture, Ecosystems & Environment 197(0), 41-52.

Begum N, Guppy C, Herridge D, Schwenke G (2014) Influence of source and quality of plant residues on emissions of N2O and CO2 from a fertile, acidic Black Vertisol. Biology and Fertility of Soils 50, 499–506.

Schwenke G. D., McLeod M. K., Murphy S. R., Harden S., Cowie A. L., Lonergan V. E. (2013) The potential for sown tropical perennial grass pastures to improve soil organic carbon in the North-West Slopes and Plains of New South Wales. Soil Research 51, 726–737.

McLeod M. K., Schwenke G. D., Cowie A. L., Harden S. (2013) Soil carbon is only higher in the surface soil under minimum tillage in Vertosols and Chromosols of New South Wales North-West Slopes and Plains, Australia. Soil Research 51, 680–694.

Begum N, Guppy C, Herridge D, Schwenke G (2013) Influence of source and quality of plant residues on emissions of N2O and CO2 from a fertile, acidic Black Vertisol. Biology and Fertility of Soils:1-8.

Brock P, Madden P, Schwenke G, Herridge D (2012) Greenhouse gas emissions profile for 1 tonne of wheat produced in Central Zone (East) New South Wales: a life cycle assessment approach. Crop and Pasture Science 63, 319-329

Dang YP, Dalal RC, Buck SR, Harms B, Kelly R, Hochman Z, Schwenke GD, Biggs AJW, Ferguson NJ, Norrish S, Routley R, McDonald M, Hall C, Singh DK, Daniells IG, Farquharson R, Manning W, Speirs S, Grewal HS, Cornish P, Bodapati N, Orange D (2010) Diagnosis, extent, impacts, and management of subsoil constraints in the northern grains cropping region of Australia. Soil Research 48, 105–119.


The Soil Unit at the Tamworth Agricultural Institute is certified under ISO 9001:2008 by BSI under certificate number FS 603588

BSI certification

Professional associations

Member of Soil Science Australia, the peak body for professional, academic and technical soil scientists across Australia.

Fields of research (ANZ standard research classification)

  • 050305 Soil Physics
  • 050303 Soil Biology
  • 050304 Soil Chemistry (excl. Carbon Sequestration Science)
  • 050302 Land Capability and Soil Degradation
  • 070306 Crop and Pasture Nutrition
  • 050205 Environmental Management
  • 050207 Environmental Rehabilitation
  • 079902 Fertilisers and Agrochemicals (Application etc.)straints management

Keyword/phrase list of research interests

  • Soil organic matter
  • Soil management
  • Crop nutrition
  • Subsoil constraints management
  • Salinity
  • Nitrous oxide emissions
  • Ammonia volatilisation
  • Soil health

Contact details

Email graeme.schwenke@dpi.nsw.gov.au
Phone: (02) 6763 1137
Mobile: 0418 636 421
Location: Tamworth Agricultural Institute