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Research Project Summaries Climate Change Research Program Nitrous Oxide Research Program

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Research Project Summaries

Contents

Overview ....................................................................................................... 4

Climate Change Research Program ................................................................ 6

Nitrous Oxide Research Program ................................................................................... 6

Integrated data and synthesis framework for reducing nitrous oxide emissions from Australian agricultural soils .................................................................................................. 7

Reducing nitrous oxide emissions from sugarcane lands .................................................. 11

Decreasing nitrous oxide emissions in high rainfall cropping systems ........................ 13

Enhanced efficiency fertilisers as mitigation tools for reducing greenhouse gas emissions from intensive agricultural systems ...................................................................... 16

Fertiliser management strategies for decreasing on-farm greenhouse gas emissions ................................................................................................................................................................... 18

The potential of inhibitors for the mitigation of nitrous oxide emissions from animal productions systems in south-eastern Australia .................................................... 20

Mitigating nitrous oxide emissions from soils using pulses and improved nitrogen management ......................................................................................................................................... 22

Reducing nitrous oxide emissions from irrigated grains-cotton farming systems .. 25

Round 1 of Filling the Research Gap ............................................................. 28

Overview .................................................................................................................... 29

National Agricultural Nitrous Oxide Research Program ................................................ 29

Managing an integrated, data synthesis and modelling research network for reducing nitrous oxide emissions from Australian soils ..................................................... 29

National coordination of an integrated, data synthesis and modelling network for reducing nitrous oxide emissions from Australian soils ..................................................... 29

Mitigation of indirect greenhouse gases in intensive agricultural production systems with the use of inhibitors ............................................................................................... 30

Reducing nitrous oxide emissions from applied nitrogen with nitrification inhibitors: Identification of the key drivers of performance ............................................. 30

The use of inhibitors to improve nitrogen cycling and reduce nitrous oxide losses from intensively grazed pasture systems ................................................................................. 30

Does increasing soil carbon in sandy soils increase soil nitrous oxide emissions from grain production? .................................................................................................................... 31

Quantifying nitrous oxide losses and nitrogen use efficiency in grains cropping systems on clay soils with contrasting soil carbon status and land management .... 31



An integrated assessment of management practices for reducing nitrous oxide emission and improving nitrogen use efficiency for subtropical dairy systems ....... 31

The effect of fertiliser nitrogen breakdown inhibitors and nitrogen rate on greenhouse gas emissions, nitrate leaching and nitrogen use efficiency in intensive dairy pasture systems in hot dry climates ................................................................................ 31

Effective management practices to reduce nitrous oxide emissions from sugarcane soils .......................................................................................................................................................... 32

Options for reducing nitrous oxide emissions from the New South Wales dryland grains industry .................................................................................................................................... 32

Improving nitrous oxide abatement in high rainfall cropping systems ........................ 32

Assessing opportunities for mitigating greenhouse gas emissions from irrigated broad-acre cropping systems in the southern Murray-Darling Basin ........................... 33

Improved carbon and greenhouse gas outcomes through better understanding and management of soils and plant inputs at the farm scale ..................................................... 33

Advanced process level understanding of factors controlling gaseous nitrogen partitioning to reduce nitrous oxide losses from Australian agricultural soils ......... 33

Characterising nitrous oxide emissions from nitrification ................................................ 33

Development of a low-emission nitrogen fertiliser based on slow release of ammonium from clay-modified activated charcoal .............................................................. 34

National Agricultural Greenhouse Gas Modelling Program .......................................... 34

Potential soil carbon sequestration in Australian grain regions and its impact on soil productivity and greenhouse gas emissions ................................................................... 34

Facilitation of improvement in systems modelling capacity for Carbon Farming Futures .................................................................................................................................................... 34

Whole farm systems analysis of greenhouse gas abatement options for the southern Australian grazing industries ..................................................................................... 35

Overview



Overview

The Climate Change Research Program (CCRP), which ended on 30 June 2012, funded research projects and on-farm demonstrations to help prepare Australia’s primary industries for climate change. Research focused on reducing greenhouse gas emissions, improving soil management and climate change adaptation, and involved projects that will lead to practical management solutions for farmers and industries.

Over four years the Australian Government invested $46.2 million in over 50 large scale collaborative research, development and demonstration projects. Total investment under the program was over $130 million and included contributions from research providers, industry groups, universities and state governments. A breakdown of the allocated government funding is below:

Reducing Emissions from Livestock Research Program—$11.3 million Nitrous Oxide Research Program—$4.7 million Soil Carbon Research Program—$9.6 million National Biochar Initiative—$1.4 million Adaptation Research Program—$11.5 million Demonstration on-farm or by food processors—$7.7 million.

Research through the CCRP has increased our understanding of the sources of agricultural emissions and the potential for emission reduction and carbon sequestration. This information has underpinned the development of the first approved methodology under the Carbon Farming Initiative and has contributed valuable data for a number of methodologies currently under consideration. This will enable farmers to generate additional on-farm income through selling carbon offsets into domestic and international carbon markets.

Filling the Research Gap, part of the $429 million Carbon Farming Futures Program under the $1.7 billion Land Sector Package, is building on research undertaken through the CCRP. Research projects are targeting current gaps around abatement technologies and practices identified through the CCRP, and will continue to support the development of offset methodologies that land managers can use to participate in the Carbon Farming Initiative.

The following summaries highlight the key findings from nitrous oxide research undertaken through the CCRP as well as related projects being funded through Round 1 of Filling the Research Gap. This information should be used by potential applicants to guide applications in climate change research for agriculture under Round 2 of Filling the Research Gap.

Potential applicants are advised to contact the lead organisations for each project for further information and are encouraged to refer to the Filling the Research Gap Research Strategy (July 2012-June 2017).

http://www.daff.gov.au/climatechange/carbonfarmingfutures/ftrg/filling-the-research-gap-july-2012-to-june-2017

Overview



Climate Change Research Program




Nitrous Oxide Research Program




Integrated data and synthesis framework for reducing nitrous oxide emissions from Australian agricultural soils

Lead organisation Queensland University of Technology

Consortium member organisations The following organisations participated in the Nitrous Oxide Research Program (NORP) through funding and/or conducting research projects: Grains Research and Development Corporation Dairy Australia Sugar Research and Development Corporation Cotton Research and Development Corporation Incitec Pivot Queensland University of Technology The University of Melbourne The University of Western Australia Department of Primary Industries, Victoria Department of Science, Information Technology, Innovation and the Arts (formerly Department of Education and Resource Management) NSW Department of Primary Industries University of New England

Objectives

reduce uncertainty regarding the magnitude of nitrous oxide (N2O), as well as methane (CH4) and carbon dioxide (CO2), emitted in response to management practices through the synthesis of emissions data collected at multiple locations across Australia, aligned with high resolution climate, soil, plant growth and management information

develop an objective national assessment of automatic chamber sampling with detailed manual sampling techniques

develop the capacity to compare management dependent N2O emissions from diverse industries, agricultural systems, soils and climates, collected at plot and field scales

use information from the comparisons above to develop objective, evidence based mitigation practices and systems that are consistent with adaptation strategies

increase capacity to improve the accuracy of simulation models and the agriculture component of Australia’s national greenhouse gas inventory.

Location Brisbane, Queensland

Key activities The NORP is a network of automated field sites and laboratory investigations assessing greenhouse gas emissions data in response to nitrogen management and the use of




inhibitors to reduce net N2O emissions across Australia’s agricultural production systems, including grain, cotton, dairy and sugarcane. Activities, findings and conclusions at the seven main field sites are summarised individually. In addition to the activities at the seven main field sites, the NORP examined the spatial variability of greenhouse gas emissions and developed a state-of-the-art web portal and database which provides researchers, growers and policy makers access to new information. The NORP also undertook preliminary simulation activities to test the accuracy of the DayCent model (the daily time-step version of the Century model) and explore its utility to extrapolate N2O mitigation strategies.

Findings/Conclusions Emissions of N2O across Australia’s diverse soils and agricultural systems varied widely, from coarse textured cropping soils of Western Australia (50 g N2O-N ha-1 annum-1) to high rainfall fertile pastures of southern Victoria and cane systems of northern Queensland (with episodes > 1 kg N2O-N ha-1 day-1). Land use and farming systems history have a major impact on N2O emissions, particularly the interaction with carbon (C) availability and especially when soil moisture levels are high (and conducive to denitrification). For example, in high rainfall southern Victoria, annual N2O emissions from cropped soils which have just come out of pasture may exceed 35 kg N2O-N, with no application of additional nitrogen (N). Similarly, in trash retained cane systems of northern Queensland emissions, N2O emissions average 16 kg N2O-N/annum. In high rainfall pastures, the combination of fertile soils that have a high organic carbon and N content and a restricted drainage system created ideal conditions for N2O production. With respect to cane, even though the topsoil C levels are relatively low (1 per cent), the high C inputs from the cane itself plays a critical role in fuelling the denitrification process which produces N2O under saturated conditions. These studies highlight the need for improved soil management to reduce the incidence of periodic waterlogging which results in denitrification. Incorporating a grain-legume in a crop rotation in the western grains region can lower greenhouse gas (GHG) emissions by up to 35 per cent per tonne of wheat through decreased CO2 emissions from the production, transport and hydrolysis of urea. The ability to substitute grain-legume fixed N for synthetic N fertiliser has also been confirmed in NORP rain fed cropping studies in eastern New South Wales. Liming acidic cropping soils in Western Australia may decrease N2O emissions resulting from nitrification following summer/autumn rainfall events, plus increased CH4 uptake throughout the year. Liming will only decrease total GHG from wheat production if decreased soil N2O emissions and increased CH4 uptake is not off-set by increased CO2 resulting from the production, transport and dissolution of the applied lime. The surface application of the nitrification inhibitor dicyandiamide (DCD) can reduce N2O emissions from urine applied to soils under dairy production in the high rainfall




zone of Victoria by 35 to 45 per cent when applied either directly after urine deposition or about a month before urine deposition. Inhibitor effects may last 10 - 30 days longer when applied in autumn compared to late winter/spring, highlighting the importance of soil temperature on the longevity of effects. Application of DCD after each urine deposition reduced emissions by about 75 per cent, although application costs would make this cost prohibitive. DCD application did not appear to show a response in pasture production and hence there may not be adequate incentive for producers to use DCD. In cane production systems of northern Queensland, 8-20 kg N2O-N ha-1 was lost during a 12 month sugarcane crop. The N2O emission factor of fertiliser N ranged from 4.0 to 6.6 per cent, which is several times higher than the international average of 1 per cent. In cane production systems, the addition of the nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) in urea reduced N2O emissions by 34 per cent. As much as 8.2 kg N2O-N ha-1 is lost from bare soil and soybean cropped soils during a seven-month sugarcane fallow period. These high N2O emissions indicate significant N nutrient losses and overall reduced N use efficiency. Growing soybean during the fallow period in a cane system supplied approximately 110 kg N ha-1 and presented an effective means to reduce N fertiliser application rate and possibly N2O emissions, although in this experiment N2O emissions increased substantially following soybean residue incorporation into soil. In addition to high N2O emissions, high CH4 emissions occurred during the wet seasons when the soil was under waterlogged conditions for prolonged periods. Overall, N2O emissions from irrigated cropping systems of southern Queensland appeared to be lower than the current emission factor for irrigated cotton (0.5 per cent) used in Australia’s national greenhouse gas inventory. The NORP rain fed emissions studies in eastern New South Wales (Tamworth) also indicated that the current emission factors for dryland cereals should be reduced. However, a single emission factor might not be appropriate for highly fertilised crops, particularly those under irrigation as emission factors have been shown to increase with the amount of N fertiliser applied. The use of the nitrification inhibitor DMPP with urea showed a marked capacity to reduce N2O fluxes during irrigated cereal production in southern Queensland, reducing N2O emissions by more than 60 per cent in a maize experiment at Kingaroy. However, the typically low N2O emissions found in irrigated crop production in southern Queensland means the overall GHG mitigation potential is limited to < 1.0 t CO2-e ha-1 yr-1. For a winter cereal crop, the risk of high N2O emissions is greatest between application of the fertiliser at sowing and its uptake by the growing crop over the ensuing months post-planting. In contrast, the period after grain harvest, during summer and autumn when the decomposing legume crop residues mineralise, is the high risk period for N2O emissions after the legume crop.




Results showed that across nine soil types, the nitrification inhibitors DCD and DMPP reduced nitrate production by up to 80 per cent and N2O emissions by 8 - 83 per cent. The range of reductions achieved was influenced by soil type and temperature, with greater reduction at lower soil temperature. The effect of temperature on the efficacy of the inhibitors was also dependent upon soil type. No individual physical or chemical soil parameter was identified as being more important for the performance of the inhibitor. Spatial variation studies on the influence of soil chemistry on N2O emissions identified both top soil water and nitrate levels as potential predictors of N2O emissions in a field situation. Both variables can be measured non-destructively in the field, with electrical conductivity providing an estimate of soil nitrate. Model simulations using DayCent displayed a high degree of parity between predicted and observed results from sites across the NORP network. This provides confidence in the further use of this model for extrapolation of the NORP field data across regions, including the development of N management strategies for mitigation of N2O emissions. The automated systems used in NORP significantly reduce uncertainty (compared to manual, periodic sampling); increase accessibility under rainfall and waterlogged conditions (when denitrification normally occurs); and are essential for integrating daily fluxes, thus eliminating significant errors associated with daily fluctuations in temperature. The automated systems provide the data foundation for accurate model calibration and testing. New systems have been installed at four additional sites (Narrabri—irrigated cotton, Griffith—irrigated wheat, Wollongbar—biochar, Gympie—dairy) with industry funding.

Related projects funded under Round 1 of Filling the Research Gap All National Agricultural Nitrous Oxide Research Program projects

Publications

1. Grace, P 2011, ‘Influence of sample timing and frequency on annual estimates of N2O, Nitrous Oxide Chamber Methodology Guidelines’, presented at the Global Research Alliance on Agricultural Greenhouse Gases meeting, Christchurch, New Zealand, 9-10 May.

2. Grace, P 2010, ‘Reducing nitrous oxide emissions’, paper presented at Farming Ahead (Kondinin Group), Sydney, 22 September.

3. Grace, P 2011, ‘Reducing agricultural N2O emissions and sustaining productivity’, paper presented at Greenhouse 2011, Cairns, 4-8 April.

4. Grace, P 2011, ‘The Australian Nitrous Oxide Research Program’, paper presented at the Climate Change Research Strategy for Primary Industries Conference, Melbourne, 15-17 February.

5. Grace, P, Barton, L, Chen, D, Eckard, R, Hely, S, Kelly, K, et. al. 2010, ‘The Australian Nitrous Oxide Research Program’, Proceedings 19th World Congress of Soil Science, Congress Symposium 4; Greenhouse gases from soils, IUSS, Gilkes, R, Prakongkep, N. (Eds.), Brisbane, pp. 247-248.




6. Grace, P, Robertson, G & Butterbach-Bahl, K 2011, ‘The impact of crop management and rotation sequences on greenhouse gas emissions from temperate and tropical soils’, paper presented at the ASA-CSSA-SSSA Annual Meeting, San Antonio, Texas, 16-19 October.

7. Scheer, C, Grace, P, Rowlings, D & Cammarano, S 2010, ‘Effect of irrigation management on nitrous oxide emissions from winter wheat’, Proceedings of the 2010 Annual Meeting of the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Long Beach, California.

8. Scheer, C, Grace, P, Rowlings, D & Payero, J 2012, ‘Nitrous oxide emissions from irrigated wheat in Australia: Impact of irrigation management’, Plant and Soil (accepted for publication).

9. Scheer, C, Grace, P, Rowlings, D & Payero, J 2012, ‘Soil N2O and CO2 emissions from cotton in Australia under varying irrigation management’, Soil Biology and Biochemistry (accepted for publication).

Further publications detailing the results of this research are in preparation and will be available.

Reducing nitrous oxide emissions from sugarcane lands

Lead organisation Department of Science, Information Technology, Innovation and the Arts (formerly Department of Education and Resource Management)

Consortium member organisations BSES Ltd Grains Research and Development Corporation Sugar Research and Development Corporation

Objectives

examine the effects of soybean cropping on nitrous oxide (N2O) emissions during the fallow period and the subsequent sugar cane cropping year

investigate the efficacy of the nitrification inhibitor DMPP (3,4-dimethylpyrazole phosphate) in reducing N2O emissions from nitrogen fertiliser

quantify annual N2O and methane (CH4) fluxes to provide data for the national greenhouse gas inventory.

Location Mackay, Queensland

Key activities The experiment was conducted during a fallow period followed by a sugarcane cropping year. Two contrasting management regimes, bare fallow and soybean cropping, were compared during the fallow period. In the succeeding sugarcane cropping, the bare fallowed soil received three different nitrogen fertilisation treatments: no fertiliser application and urea applied at 150 kg nitrogen/ha with or without addition of a nitrification inhibitor. The soybean cropped soil received either zero or 75 kg nitrogen/ha as urea.




Due to initially dry weather, followed by high rainfall and flooding, soybean was sown late and had low grain yields. As a consequence, soybean grains were not harvested, and the soybean residues were incorporated into reformed beds. Sugarcane was planted in late July 2010, treated according to the management regimes described above and harvested in July 2011. Fluxes of N2O and CH4 were monitored throughout the experimental period using both automatic and manual gas sampling chambers. Soybean grain and biomass yields and the sugarcane yield were also assessed.

Findings/Conclusions The results suggest that Australian sugarcane cropping systems can be a significant source of N2O emissions, and the researchers believe further investigation is required to identify the most effective mitigation strategies for this industry. The present study confirmed that the rate of fertiliser nitrogen (N) application under legume rotation is generally much lower than under continuous sugarcane cropping or bare fallow, as legume crops fix N from the atmosphere and supply N to the succeeding crop. In addition, soybean rotation can improve soil health and fertility and provide extra income to growers from grain sale. However, in this study soybean fallow also significantly increased N2O emissions during the late stage of the fallow period, particularly in the months following incorporation of the soybean biomass. Particular soybean residue management practices that could reduce nitrous oxide emissions and maximise nitrogen use efficiency by sugarcane crops have not yet been identified or developed. Emissions of N2O following urea application (150 kg N/ha) accounted for 4.5 per cent of the fertiliser nitrogen applied. Addition of the nitrification inhibitor DMPP in urea reduced N2O emissions by 34 per cent. However, the efficacy of nitrification inhibitors is affected by soil properties and environmental conditions. The researchers therefore suggest that the effectiveness of this technique should be assessed in other areas under different climatic conditions. Substantial CH4 emissions occurred during both fallow and cropping periods, with cumulative CH4 emissions similar between fallow and fertilisation regimes. High CH4 emissions are generally created under prolonged waterlogged conditions; given the unusually wet weather during the experimental periods, this result is not predictive of methane emissions from other soil and climatic conditions. Further research would be required to verify whether significant CH4 emissions would occur in other soil and climate conditions across sugarcane cropping regions.

Related projects funded under Round 1 of Filling the Research Gap

Effective management practices to reduce nitrous oxide emissions from sugarcane soils—Department of Science, Information Technology, Innovation and the Arts—Weijin Wang. Funding of $1 000 000 ex GST




Reducing nitrous oxide emissions from applied nitrogen with nitrification inhibitors: Identification of the key drivers of performance—The University of Melbourne—Deli Chen. Funding of $500 000 ex GST

Improved carbon and greenhouse gas outcomes through better understanding and management of soils and plant inputs at the farm scale—The University of Sydney—Mark Adams. Funding of $700 000 ex GST

Characterising nitrous oxide emissions from nitrification—CSIRO—Ryan Farquharson. Funding of $144 398 ex GST

Advanced process level understanding of factors controlling gaseous nitrogen partitioning to reduce nitrous oxide losses from Australian agricultural soils—Queensland University of Technology—Clemens Scheer. Funding of $498 761 ex GST

Publications

1. Anonymous, 2011, ‘Cutting greenhouse gases and saving on fertiliser costs’, Queensland Country Life, 1 December,

< http://qcl.farmonline.com.au/news/state/sugar/general/cutting-greenhouse-gases-and-saving-on-fertiliser-costs/2377898.aspx?storypage=1>

2. Wang, W & Dalal, R 2010, ‘Assessment of the Boundary Line Approach for Predicting N2O Emission Ranges from Australian Agricultural Soils’, Proceedings of the 19th World Congress of Soil Science, Brisbane, 1-6 August.

3. Wang, W, Dalal, R, Reeves, S, Butterbach-Bahl, K & Kiese, R 2011, ‘Greenhouse gas fluxes from an Australian subtropical cropland under long-term contrasting management regimes’, Global Change Biology, no. 17, pp. 3089-3101.

4. Wang, W, Salter, B, Reeves, S, Brieffies, T & Perna, J 2011, ‘Greenhouse Gas Emissions from Sugarcane Soil: Effects of Legume Crop Rotation and Nitrification Inhibitor Application’, The 33rd Australian Society of Sugar Cane Technologists (ASSCT) Conference, Mackay, 4-6 May.

5. Wang, W, Salter, B, Reeves, S, Brieffies, T & Perna, J 2012, ‘Nitrous oxide emissions from a sugarcane soil under different fallow and nitrogen fertiliser management regimes’, Proceedings of the Conference of Australian Society of Sugar Cane Technologists (ASSCT), Cairns, 1-5 May.


Decreasing nitrous oxide emissions in high rainfall cropping systems

Lead organisation Department of Primary Industries, Victoria

Consortium member organisations Grains Research and Development Corporation

Objectives Significant greenhouse gas emissions may occur through land use change from pasture to cropping as cropping expands in the southern Victorian high rainfall zone. Nitrous

http://qcl.farmonline.com.au/news/state/sugar/general/cutting-greenhouse-gases-and-saving-on-fertiliser-costs/2377898.aspx?storypage=1

http://qcl.farmonline.com.au/news/state/sugar/general/cutting-greenhouse-gases-and-saving-on-fertiliser-costs/2377898.aspx?storypage=1




oxide (N2O) emissions equivalent to 17 tonnes carbon dioxide/hectare/year have been measured when a high fertility legume pasture in the southern high rainfall zone was sprayed out and cropped with wheat. This project aimed to test management options for reducing the large N2O emissions that can occur during the transition from legume rich pasture to cropping cereals by: comparing direct drilling of wheat to conventional cultivation trialling application of the nitrification inhibitor dicyandiamide (DCD), including

testing whether the use of DCD could increase the nitrogen available in the soil for plant use.

Location Hamilton research station farm in western Victoria, on a site with a long history of improved pasture.

Key activities A permanent mixed ryegrass/phalaris/sub-clover pasture was sprayed to eradicate the grass and promote legume dominance. The soil was prepared for a wheat crop using either no-till or conventional tillage. DCD was also applied, giving four treatments for growing winter wheat: direct drilling, without nitrification inhibitor conventional full tillage, without nitrification inhibitor direct drilling, with DCD applied to the soil conventional full tillage, with DCD applied to the soil. DCD was applied at the end of autumn, just prior to winter rainfall. N2O release from the soil, as well as carbon dioxide levels, were measured using automatic gas collection chambers connected to a tuneable diode laser. The chambers were shifted around the plot sites every two weeks to minimise disruption to the normal growing pattern of the crop. Crop yield and N content, soil nitrate dynamics, soil moisture and soil temperature were monitored in order to understand the underlying drivers of N2O emissions in the different management systems. The experiment was repeated over two years to measure the effect of different weather on the cropping treatments.

Findings/Conclusions Very large emissions of N2O were measured in two relatively wet years with cumulative N2O emissions of 35 kg N/ha in the first monitoring year and 13 kg N/ha in the second monitoring year across all treatments. While estimates of annual N2O emissions over 30 kg N/ha are not unknown, they are generally recorded at sites where N fertiliser has been liberally applied. No N fertiliser was applied in this experiment and the only source of N was from the breakdown of the former pasture. The high level of N2O emissions was most likely the result of a combination of factors: The high rainfall in the region encouraged plenty of legume fixation of N under the

previous clover and grass pasture and this formed high levels of organically fixed N in the soil.




Soil N was further increased by spraying out the grass and encouraging clover growth in the clean-up phase in the year before cropping.

Soil at the site was relatively acid, which can increase N2O emissions. The soil at the Hamilton site has a perched water table, meaning that heavy clay in

the subsoil slows down drainage. This causes the soil to stay wet after rain for longer which creates optimum conditions for the production of N2O.

Mitigation options tested (reduced tillage and nitrification inhibitor spray) appeared to have a limited effect on reducing N2O emissions. Reducing tillage by direct drilling the seed, or spraying DCD nitrification inhibitor onto the soil, did not significantly reduce N2O emissions in the first year of the project.


Improving nitrous oxide abatement in high rainfall cropping systems—Department of Primary Industries, Victoria—Rob Harris. Funding of $1 415 000 ex GST

Options for reducing nitrous oxide emissions from the NSW dryland grains industry—NSW Department of Primary Industries—Graeme Schwenke. Funding of $1 603 371 ex GST


Mitigation of indirect greenhouse gases in intensive agricultural production systems with the use of inhibitors—The University of Melbourne—Helen Suter. Funding of $576 446 ex GST

The use of inhibitors to improve nitrogen cycling and reduce nitrous oxide losses from intensively grazed pasture systems—Department of Primary Industries, Victoria—Kevin Kelly. Funding of $700 000 ex GST

Publications

1. Officer, S, Kelly, K, Kearney, G & Graham, J 2011, ‘Mitigating effect of tillage practice and a nitrification inhibitor on nitrous oxide emissions after conversion from pasture to cropping; preliminary results after one year of continuous monitoring by automatic chambers’, paper presented at the ASA-CSSA-SSSA Annual Conference, San Antonio, Texas, 17-19 October.

2. Officer, S, Kearney, G, Kelly, K & Graham, J 2012, ‘Large nitrous oxide emissions after conversion from pasture to cropping in temperate south eastern Australia’, paper presented at the SSA-NZSSS Conference, Hobart, Tasmania, 2-7 December.


More information on the project can be found on the Primary Industries Climate Challenges Centre website at http://piccc.org.au/research/projects/nitrous-oxide/cropping

http://piccc.org.au/research/projects/nitrous-oxide/cropping

http://piccc.org.au/research/projects/nitrous-oxide/cropping




Enhanced efficiency fertilisers as mitigation tools for reducing greenhouse gas emissions from intensive agricultural systems

Lead organisation The University of Melbourne

Consortium member organisations Incitec Pivot Fertilisers Grains Research and Development Corporation

Objectives

identify the most promising enhanced efficiency fertilisers for improving nitrogen (N) fertiliser efficiency which are potentially suitable for the identified agricultural industries and regions in Australia

develop practical guidelines for use of enhanced efficiency fertilisers in the targeted industries for mitigation of nitrous oxide (N2O) emissions.

Location The University of Melbourne (laboratory components) and a commercial farm in Murroon, southwest Victoria (field components)

Key activities Laboratory and field experiments were used to investigate the potential for enhanced efficiency fertilisers to mitigate N2O emissions. The laboratory experiments examined the impact of different factors (soil, climate and inhibitor) on the efficacy of enhanced efficiency fertilisers that incorporated the nitrification inhibitors dicyandiamide (DCD), 3,4-dimethylpyrozole phosphate (DMPP) and nitrapyrin. A total of nine chemically and physically different soils were examined, including three from sugarcane growing regions, one from the central New South Wales grain producing region, three pasture soils and two pasture soils converted to cropping. The field experiment enabled a field validation of the results seen in the laboratory by measuring nitrogen transformations, N2O emissions and biomass production with different enhanced efficiency fertilisers. Field trials were conducted on ryegrass and had two components. The first, on a large area, compared ammonia (NH3) loss from top dressed granular urea, Green Urea (containing Agrotain, a urease inhibitor), urea ammonium nitrate (UAN) applied as a solution in water, and urea applied as a fine particle spray (FPA). The second component was a small plot trial comparing outcomes following applications of granular urea, urea with nitrification inhibitors (DMPP, DCD, UAN, FPA) and Green Urea. Factors assessed were N2O emissions, soil mineral N, biomass production and N content, and fate of the applied N.

Findings/Conclusions Nitrification inhibitors were found to reduce N2O emissions from a range of soils and agricultural industries under different climatic conditions by up to 90 per cent. Use of Green Urea instead of granular urea reduced NH3 loss by 68 per cent.




The impact of the urease inhibitor was found to be highly climate dependent. Emissions of N2O increased with the use of Green Urea in a field trial. This result highlights the need for targeting application of enhanced efficiency fertilisers. Sugarcane production has been identified as an enterprise with high N inputs where the use of nitrification inhibitors can reduce direct and indirect N2O emissions (from nitrate leaching). Results from three sugarcane soils (two from Mackay and one from Pin Gin) showed that N2O emissions could be reduced by up to 75 per cent and that industries that apply urea to the soil surface would gain the greatest benefit from the use of Green Urea. The greatest reductions in N2O emissions were observed in pasture soils, sugarcane soils and soils converted from pasture to grain. The effectiveness of the inhibitor to reduce N2O emissions decreased with increasing temperature, but this effect was also dependent upon the soil type.



Mitigation of indirect greenhouse gases in intensive agricultural production systems with the use of inhibitors—The University of Melbourne—Helen Suter. Funding of $576 446 ex GST


Development of a low-emission nitrogen fertiliser based on slow release of ammonium from clay-modified activated charcoal—University of Newcastle—Scott Donne. Funding of $300 000 ex GST

Publications

1. Suter, H, Chen, D & Li, H 2011, ‘Nitrification inhibitors to reduce N2O emissions from Australian farming systems’, paper presented at the Climate Change Research Strategy for Primary Industries Conference, Melbourne, 15-17 February.

2. Suter, H, Chen, D, Li, H, Edis, R & Walker, C 2010, ‘Comparison of the ability of the nitrification inhibitors DCD and DMPP to reduce nitrification and N2O emissions from nitrogen fertilisers’, paper presented at the 19th World Congress of Soil Science, Soil Solutions for a Changing World, Brisbane, 1-6 August.

3. Suter, H, Chen, D, Li, H, Edis, R & Walker, C 2010, ‘Reducing N2O emissions from nitrogen fertilisers with the nitrification inhibitor DMPP’, paper presented at the 19th World Congress of Soil Science, Soil Solutions for a Changing World, Brisbane, 1-6 August.

4. Suter, H, Chen, D & Sultana, H 2012, ‘Use of the nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) to reduce N2O emissions from pastures in southern Australia’, paper presented at the FAO/IAEA Symposium: Managing Soils for Food Security and Climate Change Adaptation and Mitigation, Vienna, Austria, 23-27 July.




5. Suter, H, Chen, D & Turner, D 2012, ‘Stabilised nitrogen fertilisers to reduce greenhouse gas emissions and improve nitrogen use efficiency in Australian agriculture’, paper presented at the FAO/IAEA Symposium: Managing Soils for Food Security and Climate Change Adaptation and Mitigation, Vienna, Austria, 23-27 July.

6. Suter, H, Chen, D, Walker, C & Davies, R 2012, ‘The potential for inhibitor stabilised nitrogen fertilisers to mitigate direct and indirect greenhouse gas emissions in agriculture’, 16th Australian Agronomy Conference, University of New England, 14-18 October (Abstract submitted).

7. Suter, H, Sultana, H, Davies, R, Mahoney, M & Chen, D 2011, ‘A field study on the impact of the nitrification inhibitor DMPP on N2O emissions from a pasture in south western Victoria’, paper presented at the Climate Change Research Strategy for Primary Industries Conference, Melbourne, 15-17 February.

8. Suter, H, Sultana, H, Walker, C, Davies, R & Chen, D 2012, ‘Use of nitrification inhibitors to reduce N2O emissions from southern pastures’, 16th Australian Agronomy Conference, University of New England, 14-18 October (Abstract submitted).


Fertiliser management strategies for decreasing on-farm greenhouse gas emissions

Lead organisation The University of Western Australia

Consortium member organisations Department of Agriculture and Food, Western Australia Grains Research and Development Corporation

Objectives Develop and verify farm management strategies for decreasing on-farm greenhouse gas (GHG) emissions resulting from the use of nitrogen fertiliser in rain-fed grain growing areas in Australia. Specifically, the project investigated whether on-farm carbon dioxide (CO2) emissions from urea could be decreased by substituting urea with grain-legume (lupin) fixed nitrogen (N), and if on-farm nitrous oxide (N2O) emissions could be decreased by raising soil pH via liming.

Location Wongan Hills Research Station, Western Australia

Key activities The project quantified and compared GHG emissions from a lupin-wheat rotation and wheat-wheat rotation, and also investigated the impact of liming on GHG emissions from both rotations. The study incorporated N2O and methane (CH4) emissions measured during a two year field study with a life cycle analysis that accounted for all GHG emissions from grains production. The analysis enabled calculation of the amount




of CO2-equivalents produced per hectare per year and per tonne of wheat for both cropping rotations, with or without soil lime.

Findings/Conclusions Incorporating a grain-legume (lupin) in a crop rotation can lower total GHG emissions from wheat production. Including lupin in the cropping rotation lowered emissions by up to 56 per cent on a per hectare per year basis, or by up to 35 per cent per tonne of wheat. Incorporating lupins in the cropping rotation decreased CO2 emissions from the production, transport and hydrolysis of urea. The extent to which incorporating grain-legumes in cropping rotations lowers emissions will depend upon the amount of urea that is saved by substituting grain-legume fixed nitrogen for synthetic nitrogen fertiliser. In rain fed cropping systems that receive annual N fertiliser inputs, liming acidic cropping soils may decrease N2O emissions following summer/autumn rainfall events, plus increase CH4 uptake throughout the year. In the wheat-wheat rotation, liming decreased N2O emissions from summer/autumn rainfall by up to 30 per cent and increased CH4 uptake by 79 per cent. Liming cropping soils will only decrease total GHG emissions from wheat production if decreased soil N2O emissions and increased CH4 uptake is not off-set by increased CO2 resulting from the dissolution of the applied lime. This study has shown that incorporating a grain-legume in a crop rotation is one strategy for lowering GHG emissions from wheat production in rain-fed cropping systems. Soil liming shows potential for decreasing soil N2O emissions following summer/autumn rainfall events. However, further research is required to determine the broader applicability of this approach and to assess CO2 emissions resulting from the application of lime to land.


Does increasing soil organic carbon in sandy soils increase soil nitrous oxide emissions from grain production?—The University of Western Australia—Louise Barton. Funding of $707 221 ex GST

Publications

1. Barton, L 2010, ‘Lupins and lime monitored in an effort to lower emissions’, Grains Research and Development Corporation Ground Cover, May-June.

2. Barton, L 2010, ‘Soil N2O fluxes are low from a grain-legume crop grown in a semi-arid climate’, paper presented at 19th World Congress of Soil Science, Brisbane, 1-6 August.

3. Barton, L 2011, ‘Greenhouse gas emissions from food and biofuel production: Contribution of soil N2O emissions’, paper presented at Climate Change Research Strategy for Primary Industries Conference, Melbourne,15-17 February.

4. Barton, L, Biswas, W, Butterbach-Bahl, K, Kiese, R, Carter, D & Murphy, D 2011, ‘The contribution of soil N2O emissions to the carbon footprint of wheat and biodiesel production in Western Australia’, Western Australia Soil Science Conference, Busselton, Western Australia, 23-24 September.

5. Barton, L, Butterbach-Bahl, K, Kiese, R & Murphy, DV 2010, ‘Three years of continuous nitrous oxide emissions from a cropped soil in a semi-arid climate (Australia)’, online poster presented at the ASA-CSSA-SSSA Conference, Long Beach, California, USA, 31 October-4 November.




6. Barton, L, Butterbach-Bahl, K, Kiese, R & Murphy, DV 2011, ‘Nitrous oxide fluxes from a grain-legume crop (narrow-leafed lupin) grown in a semi-arid climate’, Global Change Biology, vol. 17, pp. 1153-1166.

7. Barton, L, Murphy, D, Kiese, R & Butterbach-Bahl, K 2010, ‘Soil nitrous oxide and methane fluxes are low from a bioenergy crop (canola) grown in a semi-arid climate’, Global Change Biology Bioenergy, vol. 2, pp. 1-15.

8. Biswas, W, Barton, L & Carter, D 2011, ‘Biodiesel production in a semi-arid environment—a life cycle assessment approach’, Environmental Science and Technology, vol. 45, pp. 3069-3074.

9. Grains Research and Development Corporation, 2012, ‘Greenhouse gas emissions from grain production', published in the Grains Research and Development Corporation’s 'Top Paddock' series, March.

10. Grains Research and Development Corporation, 2012, 'Using legumes to reduce nitrogen loss and nitrous oxide emissions', published in the Grains Research and Development Corporation’s 'Top Paddock' series, March.

11. Li, Y, Barton, L & Chen, D 2012, ‘Simulating response of N2O emissions to fertiliser N application and climatic variability from a rain-fed and wheat-cropped soil in Western Australia’, Journal of Science of Food and Agriculture, vol. 92, pp. 1130-1143.


The potential of inhibitors for the mitigation of nitrous oxide emissions from animal productions systems in south-eastern Australia

Lead organisation Department of Primary Industries, Victoria

Consortium member organisations Dairy Australia

Objectives

to demonstrate and quantify the mitigation potential of inhibitors to reduce direct nitrous oxide (N2O) emissions from urine deposition

to define the mitigation potential and the timing of inhibitor applications required to optimise efficacy

to define the impact on pasture dry matter (DM) production and nutritive characteristics through the use of inhibitors.

Location A core site was established at DemoDAIRY, a community owned research and demonstration dairy farm near Terang in southwest Victoria. Five additional sites in southwest Victoria were also sampled.

Key activities This project used an automated chamber system linked to a Fourier Transform Infrared (FTIR) spectrometer to intensively study N2O emissions from urine patches in




southwest Victoria, using a range of application timings of both urine and the nitrification inhibitor dicyandiamide (DCD). The same treatments were applied across a range of rainfall and soil types, with sites being monitored for soil mineral nitrogen fractions and DM production. Two major experiments, each with two parts, examined aspects of the application of DCD in late winter and late autumn on N2O emissions from urine patches. In the first experiment, DCD was applied either one month before or immediately after urine was applied. In the second experiment, urine was applied up to five months after DCD application. Each of the experiments had 4 to 6 sites where the same treatments were applied using ‘synthetic urine’ and were assessed for the impact of treatment on yield and soil mineral nitrogen content. A third experiment was shorter in duration and examined the impact of nitrification inhibitors on N2O emissions following urea fertiliser application.

Findings/Conclusions A single application of DCD in late winter or late autumn reduced N2O emissions by 35 - 45 per cent when DCD was applied up to three months prior to urine application, or immediately after urine application. Emissions of N2O were further reduced when DCD was applied after each of multiple urine applications. A single application of DCD had minimal effects on pasture production. Applying a nitrification inhibitor with fertiliser (urea) also reduced nitrous oxide emissions, but again did not improve dry matter yield. This research provided further evidence that nitrification inhibitors do reduce N2O emissions under conditions experienced in southwest Victoria. However, the small and inconsistent DM production response to DCD application in association with urine deposition or fertiliser application suggests that DCD does not lead to a measureable increase in pasture production. As such, improvements in dry matter production are not likely to provide an incentive for industry to surface apply DCD. The use of nitrification inhibitors to reduce N2O emissions has potential for development of a methodology under the Carbon Farming Initiative. However, preliminary estimates indicate the cost of application far outweighs the likely returns at the current carbon price. The researchers noted that findings on the impacts of inhibitors on N2O emissions and production should be verified and investigated under a wider range of soil type and conditions.






An integrated assessment of management practices for reducing nitrous oxide emissions and improving nitrogen use efficiency for subtropical dairy systems—Queensland University of Technology—David Rowlings. Funding of $500 000 ex GST

The effect of fertiliser nitrogen breakdown inhibitors and nitrogen rate on greenhouse gas emissions, nitrate leaching and nitrogen use efficiency in intensive dairy pasture systems in hot dry climates—NSW Department of Primary Industries—Graham Denney. Funding of $731 614 ex GST

Reducing nitrous oxide emissions from applied nitrogen with nitrification inhibitors through identification of the key drivers of performance—The University of Melbourne—Deli Chen. Funding of $500 000 ex GST

Publications

1. Huggins, T, Kelly, K, Suter, H & Eckard, R 2011, ‘Is it commercially viable to use dicyandiamide on a commercial dairy farm in south-western Victoria?’, paper presented at Climate Change Research Strategy for Primary Industries Conference, Melbourne, 14-17 February.

2. Kelly, K, Ward, G, Officer, S, Huggins, T & Eckard, R 2011, ‘Can we reduce nitrous oxide emissions from animal production systems?’, paper presented at Climate Change Research Strategy for Primary Industries Conference, Melbourne, 14-17 February.

3. Primary Industries Climate Challenges Centre, 2012, ‘The potential of inhibitors for the mitigation of nitrous oxide emissions from animal production systems in south-eastern Australia’, <http://piccc.org.au/research/projects/nitrous-oxide/inhibitors>

4. Primary Industries Climate Challenges Centre, 2012, ‘Reducing nitrous oxide emissions from agriculture’, <http://piccc.org.au/resource/fact-sheets/198>


Mitigating nitrous oxide emissions from soils using pulses and improved nitrogen management

Lead organisation University of New England

Consortium member organisations NSW Department of Primary Industries Grains Research and Development Corporation

Objectives To measure and compare the soil nitrous oxide (N2O) emissions from a range of dryland crops and crop rotations in the northwest New South Wales grains region. In particular, the research focused on the N2O emissions associated with the growth of annual legume species, the subsequent breakdown of their residues and the uptake of their residual nitrogen by a following wheat crop.

http://piccc.org.au/research/projects/nitrous-oxide/inhibitors

http://piccc.org.au/research/projects/nitrous-oxide/inhibitors

http://piccc.org.au/resource/fact-sheets/198




Location Tamworth, northwest New South Wales

Key activities Two crop rotation experiments were conducted on a cracking clay soil representative of the dominant soil type used for grain growing in Australia’s northeast grains region. The first experiment compared the soil N2O emissions from four cropping rotations representative of commercial farming practice in the region: (T1) canola+N_wheat+N_barley+N (= high N treatment) (T3) chickpea_wheat+N_barley (T4) chickpea_wheat_chickpea (= low N treatment) (T5) chickpea_sorghum+N. The experiment was laid out in a randomised block design with each crop rotation treatment replicated four times. Emissions of N2O from the soil were monitored 7-8 times per day for a year using an automated system of chambers connected to a gas chromatograph. Mineral N concentration in the soil and the uptake of N into plant biomass were also monitored. The second experiment compared the soil N2O emissions from three commonly grown winter legumes (chickpea, fababean and fieldpea) with canola, and oilseed. These crops were followed by wheat, either with or without N fertiliser added. The experiment was laid out in a randomised block design with each legume treatment replicated four times. Emissions of N2O from the soil were assessed using manual chamber measurements at least once per week over much of the entire experimental period, less often during extended dry periods. Mineral N concentration in the soil and the uptake of N into plant biomass were also monitored.

Findings/Conclusions The timing of N2O loss from fertiliser application to winter cereal crops and from nitrogen input to the soil-plant system through legume N2 fixation are different, and should be considered separately in assessing mitigation options for the grains industry. For a winter cereal crop, greatest emissions occur between application of the fertiliser at sowing and uptake of fertiliser nitrogen by the growing crop over the ensuing months. In contrast, N2O emissions during legume growth in a dryland crop rotation are small to nil; the risk of high emissions occurs in the period after grain harvest, during summer and autumn when the decomposing legume crop residues mineralise. Heavy rainfall and saturated soils in either of these two periods can trigger emission losses. The oilseed canola is a N-rich crop that is not a legume, but produces crop residues as high in their N content as the legumes trialled. This means that it too can generate significant quantities of mineral N that may be denitrified to N2O under suitable conditions. In comparison with chickpea, canola mineralisation began earlier, as its leaves dropped as the plant matured. Higher N2O losses were observed from the post-harvest canola than the post-harvest chickpea, because more mineralisation had already taken place by the end of the calendar year when constant heavy rainfall triggered emission losses.




Australia uses an emission factor of 0.3 per cent for fertilised dryland winter cereals in compiling the national greenhouse gas emissions inventory. In this study, emission factors for fertilised dryland winter cereals were higher than the figure of 0.3 per cent when unseasonally wet conditions in winter led to immediate losses after application, and lower than the national figure when conditions were drier than normal. Based on this the researchers believe the national figure is probably a reasonable assumption for fertiliser applied to winter crops in this region. Growing legume crops in rotation with cereals may not reduce direct N2O emissions, but their ability to fix atmospheric N2 reduces the need for N fertiliser, both for the legume crop and following cereal crops. This results in a significant reduction in the greenhouse gases emitted during the production and transport of the N fertiliser. Findings in this research indicated that the emissions factor of one per cent currently in use for legume crops in Australia’s greenhouse gas emissions inventory is probably too high. While emissions factor results varied with the legume crop and its N2 fixation performance in the study, most were below one per cent.




Effective management practices to reduce nitrous oxide emissions from sugarcane soils—Department of Science, Information Technology, Innovation and the Arts—Weijin Wang. Funding of $1 000 000 ex GST

Improved carbon and greenhouse gas outcomes through better understanding and management of soils and plant inputs at the farm scale—The University of Sydney—Mark Adams. Funding of $700 000 ex GST

Publications

1. 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, vol. 63, no. 4, pp. 319-329.

2. Schwenke, G, Brock, P & Herridge, D 2011, ‘Nitrogen fixing legumes in farming systems reduce greenhouse gas emissions’, paper presented at the 17th Nitrogen Fixation Congress, Fremantle, Western Australia, 27 November-1 December.

3. Schwenke, G, Haigh, B, McMullen, G, Brock, P & Herridge, D 2012, ‘Nitrous oxide - an indicator of N loss?’, GRDC Grains Research Update, Dubbo, pp. 120-121.

4. Schwenke, G, Haigh, B, McMullen, G & Herridge, D 2010, ‘Soil nitrous oxide emissions under dryland N-fertilised canola and N2-fixing chickpea in the northern grains region, Australia’, paper presented at the 19th World Congress of Soil Science: Soil Solutions for a Changing World, Brisbane, 1-6 August.

5. Schwenke, G, Herridge, D, McMullen, K, Haigh, B & Baker, K 2011, ‘Emission of nitrous oxide from a cracking clay soil used to grow canola and chickpea in the northern grains




region’, paper presented at the Climate Change Research Strategy for Primary Industries Conference, Melbourne, 15-17 February.

6. Schwenke, G, Herridge, D, McMullen, K, Haigh, B & Baker, K 2011, ‘Nitrous oxide emissions from dryland cropping soil in northwest NSW’, paper presented at Primary Industries Innovation Centre Rural Climate Change Solutions Symposium, Armidale, 3-4 May.

7. Schwenke, G, Herridge, D, McMullen, K, Haigh, B & Leedham, K 2012, ‘Legumes in crop rotations reduce nitrous oxide emissions compared to fertilised non-legume rotations’, paper presented at the International Symposium on Managing Soils for Food Security and Climate Change Adaptation and Mitigation, Vienna, Austria, 23-26 July.


Reducing nitrous oxide emissions from irrigated grains-cotton farming systems

Lead organisation Queensland University of Technology

Consortium member organisations Grains Research and Development Corporation

Objectives Develop and verify strategies for decreasing on-farm greenhouse gas (GHG) emissions resulting from the use of nitrogen fertiliser in irrigated cotton-grains farming systems. In particular, the project investigated how nitrous oxide (N2O) emissions could be decreased through improved irrigation and fertiliser management and the use of nitrification inhibitors.

Location Queensland government research stations at Kingsthorpe and Kingaroy, Queensland

Key activities This project quantified and compared GHG emissions from a wheat-cotton (Kingsthorpe) rotation and wheat-corn (Kingaroy) rotation. Research at the Kingsthorpe station investigated the impact of irrigation intensity and fertiliser rates on the emissions of N2O. Research at the Kingaroy station investigated the impact of fertiliser rates and the use of nitrification inhibitors on the emissions of N2O. The agronomic performance of the different treatments was also quantified and used to estimate the N2O intensity of the cropping system (amount of N2O emitted per tonne of crop yield produced).

Findings/Conclusions N2O emission factors for irrigated cotton-grains systems in these studies ranged from 0.1 to 0.6 per cent of total nitrogen (N) applied. This is considerably lower than the Intergovernmental Panel on Climate Change (IPCC) default value (1 per cent of N




applied) and in many instances lower than the emission factor for irrigated cotton used in compiling Australia’s national GHG inventory (0.5 per cent of N applied). Highest N2O emissions occurred after rainfall or irrigation events and the amount of irrigation water applied influenced the magnitude of the emission pulse. Management practices with the potential to reduce N2O emissions from irrigated cropping systems include avoiding large irrigation volumes after fertilisation or when the soil mineral N content is high, as well as avoiding large applications of fertiliser N before planting. Applying the nitrification inhibitor 3,4 dimethylpyrazole phosphate (DMPP) with urea reduced N2O fluxes by more than 60 per cent during the corn season in Kingaroy. The researchers concluded that future work should focus on increasing the N use efficiency of a system by better matching crop N demand to soil N supply (avoiding large single applications of N fertiliser) and optimising the N2O intensity of production through irrigation management.

Small irrigation volumes in regular intervals or when the available water content is depleted will limit large pulses of soil N2O emissions but will maintain production by helping to avoid plant water stress, reducing the N2O intensity of a cropping system.


Advanced process level understanding of factors controlling gaseous nitrogen partitioning to reduce nitrous oxide losses from Australian agricultural soils—Queensland University of Technology—Clemens Scheer. Funding of $498 761 ex GST

Characterising nitrous oxide emissions from nitrification—CSIRO—Ryan Farquharson. Funding of $144 398 ex GST


Publications

1. Grace, P, Barton, L, Chen, D, Eckard, R, Hely, S, Kelly, K, et. al. 2010, ‘The Australian Nitrous Oxide Research Program’, Proceedings 19th World Congress of Soil Science, Congress Symposium 4; Greenhouse gases from soils, IUSS, Gilkes, RJ, Prakongkep, N (Eds.), Brisbane, pp. 247-248.

2. Scheer, C, Grace, P, Rowlings, D & Cammarano, S 2010, ‘Effect of irrigation management on nitrous oxide emissions from winter wheat’, paper presented at the Annual Meeting of the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Long Beach, California, 31 October-3 November.

3. Scheer, C, Grace, P, Rowlings D & Payero, J 2012, ‘Nitrous oxide emissions from irrigated wheat in Australia: Impact of irrigation management’, Plant and Soil, vol. 359, no. 1-2, pp. 351-362.

4. Scheer, C, Grace, P, Rowlings, D & Payero, J 2012, ‘Soil N2O and CO2 emissions from cotton in Australia under varying irrigation management’, Soil Biology and Biochemistry (Submitted).




Round 1 of Filling the Research Gap




Overview

Filling the Research Gap supports research into emerging abatement technologies, strategies and innovative management practices that reduce greenhouse gas emissions from the land sector, store soil carbon and enhance sustainable agricultural practices.

A total of 57 successful projects are being undertaken under Round 1 of the program. These projects share $47 million in Australian Government funding over the years 2011–12 to 30 June 2015 and are grouped into five sub-programs:

National Livestock Methane Program National Agricultural Manure Management Program National Agricultural Nitrous Oxide Research Program National Soil Carbon Program National Agricultural Greenhouse Gas Modelling Program.

The following projects are been funded under Round 1 of Filling the Research Gap to participate in the National Agricultural Nitrous Oxide Research Program and the National Agricultural Greenhouse Gas Modelling Program. Descriptions of all successful Round 1 projects are available at http://www.daff.gov.au/climatechange/carbonfarmingfutures/ftrg.

National Agricultural Nitrous Oxide Research Program

Managing an integrated, data synthesis and modelling research network for reducing nitrous oxide emissions from Australian soils—Grains Research and

Development Corporation—Martin Blumenthal. Funding of $400 000 ex GST

This project will provide the overall management and reporting linkages between the Department of Agriculture, Fisheries and Forestry and researchers selected through the Filling the Research Gap Program in the delivery of the National Agricultural Nitrous Oxide Research Program.

National coordination of an integrated, data synthesis and modelling network for reducing nitrous oxide emissions from Australian soils—

Queensland University of Technology—Peter Grace. Funding of $1 992 259 ex GST

This project aims to deliver a suite of mitigation strategies to reduce nitrous oxide emissions from Australian agricultural soils which embrace the synergies of the soil carbon and nitrogen cycles, increase nitrogen use efficiency, long-term productivity and profitability. This will be achieved through complementary laboratory and field studies, data integration, synthesis and modelling under the management of the Grains Research

http://www.daff.gov.au/climatechange/carbonfarmingfutures/ftrg




and Development Corporation. The project will close research gaps, improve modelling capability and link relevant rural research, demonstration and extension programs.

Mitigation of indirect greenhouse gases in intensive agricultural production systems with the use of inhibitors—The University of Melbourne—Helen Suter.

Funding of $576 446 ex GST

This project will quantify the mitigation of ammonia volatilisation from nitrogen fertilisers in intensive agricultural production systems (dairy, vegetables) resulting from the use of inhibitors. Micrometeorological techniques will be used to measure ammonia volatilisation. It will also obtain a nitrogen mass balance through the use of 15N labelled fertilisers on collaborative field sites, and to provide data to improve the capability of nitrogen models to simulate ammonia volatilisation. The data on the potential mitigation of ammonia volatilisation by inhibitors, and nitrogen mass balance are essential for establishing methodologies to reduce indirect nitrous oxide emission.

Reducing nitrous oxide emissions from applied nitrogen with nitrification inhibitors: Identification of the key drivers of performance—The University of

Melbourne—Deli Chen. Funding of $500 000 ex GST

This project aims to quantify reductions in nitrous oxide emissions through use of nitrification inhibitors that have different properties in a variety of climatic conditions and soils. It will determine why the inhibitors work only in some soils and develop algorithms describing inhibitor impact on nitrous oxide emissions for existing models. It will also verify model predictions using field trials. The project will lead to a clear set of soil and environmental factors for determining the potential of nitrification inhibitors for decreasing nitrous oxide emissions across a range of soils and climates while using less nitrogen and maintaining yield.

The use of inhibitors to improve nitrogen cycling and reduce nitrous oxide losses from intensively grazed pasture systems—Department of Primary

Industries, Victoria—Kevin Kelly. Funding of $700 000 ex GST

This project will address both productivity and emission mitigation implications of inhibitor use in dairy systems in south eastern Australia. The project will evaluate the potential of nitrification inhibitors to reduce direct emissions from urine on pasture. It will examine the impact of feeding the inhibitor dicyandiamide to livestock, and evaluate the mitigation potential of inhibitor coated inorganic fertiliser applied to pastures in dairy systems. It will also evaluate the efficacy of inhibitors with re-use of dairy effluent streams on farm. Project outputs will contribute significantly to the development of methodologies for recognition of emission offsets by the use of inhibitors under the Carbon Farming Initiative.




Does increasing soil carbon in sandy soils increase soil nitrous oxide emissions from grain production?—The University of Western Australia—Louise

Barton. Funding of $707 221 ex GST

The project will investigate if increasing the amount of carbon stored in the soil will alter emissions of nitrous oxide, affect crop production or alter the amount of nitrogen fertiliser needed to produce a profitable crop. Understanding how increasing soil carbon effects soil nitrous oxide emissions and crop production will enable us to assess the suitability of soil carbon sequestration for abating greenhouse gas emissions from land.

Quantifying nitrous oxide losses and nitrogen use efficiency in grains cropping systems on clay soils with contrasting soil carbon status and land management—Queensland Alliance for Agriculture and Food Innovation / University

of Queensland—Mike Bell. Funding of $1 598 997 ex GST

Declining soil organic matter and mineralisable nitrogen reserves characterise grain cropping soils in Queensland. Management responses include increasing fertiliser nitrogen use or increasing soil organic matter and mineralisable nitrogen with pasture leys, manures and more frequent use of leguminous species. The effectiveness of these strategies on sustainably and efficiently meeting system nitrogen demand, maintaining or improving soil carbon stocks and minimising losses of nitrous oxide have not been determined. This project will quantify the effects of these strategies on fertiliser nitrogen requirement, gaseous nitrogen losses and soil carbon status.

An integrated assessment of management practices for reducing nitrous oxide emission and improving nitrogen use efficiency for subtropical dairy systems—Queensland University of Technology—David Rowlings. Funding of

$500 000 ex GST

This project will determine the fate of applied nitrogen fertiliser to a subtropical dairy production system at the paddock and farm scales and examine the effectiveness of methane, nitrous oxide and nitrogen loss mitigation strategies. This study will produce high quality datasets and whole-farm modelling, costs/benefits of mitigation, and practical strategies for developing Carbon Farming Initiative offset methodologies to reduce nitrous oxide and methane emissions whilst maintaining productivity.

The effect of fertiliser nitrogen breakdown inhibitors and nitrogen rate on greenhouse gas emissions, nitrate leaching and nitrogen use efficiency in intensive dairy pasture systems in hot dry climates—NSW Department of

Primary Industries—Graham Denney. Funding of $731 614 ex GST

This project will quantify the effect of fertiliser nitrogen breakdown inhibitors and nitrogen fertiliser rate on greenhouse gas emissions, nitrate leaching and nitrogen use efficiency. Two field experiments will be undertaken using automated chambers to provide high resolution emission data. The research site at Camden, New South Wales is




representative of the hot-dry climate of a large part of New South Wales and northern Victorian dairying. This research will generate scientifically defensible data on the effect of inhibitors and applied nitrogen rate on greenhouse gas emissions for hot-dry dairying environments that will contribute to development of offset methodologies for the dairy industry under the Carbon Farming Initiative.

Effective management practices to reduce nitrous oxide emissions from sugarcane soils—Department of Science, Information Technology, Innovation and the

Arts—Weijin Wang. Funding of $1 000 000 ex GST

This project will identify best management practices for mitigating nitrous oxide emissions in sugarcane production. The research will use state-of-the-art approaches including automatic gas sampling chambers, big manual chambers, stable isotope tracing and modelling to provide robust scientific data and evidence-based advice. Environmentally effective and economically efficient mitigation strategies for different ecological conditions and management regimes will be identified and communicated to stakeholders through strong government and industry participation. These activities will help promote low-emission farming practices in the sugar industry.

Options for reducing nitrous oxide emissions from the New South Wales dryland grains industry—NSW Department of Primary Industries—Graeme

Schwenke. Funding of $1 603 371 ex GST

This project will reduce nitrous oxide emissions from dry land grains cropping in northern and southern New South Wales through improving the nitrogen use efficiency of applied nitrogenous fertiliser, substituting fertiliser nitrogen with legume-derived nitrogen and modification to soil tillage. Treatments will include split application of fertiliser nitrogen, fertiliser containing inhibitors, and tillage by rotation practices. Measurements of nitrous oxide will be field based, primarily using automated GHG sampling chambers. Results will be modelled to improve capability for predicting nitrous oxide emissions from dry land cropping. Project outputs will contribute to the development of Carbon Farming Initiative methodologies for more efficient nitrogen fertiliser use.


This project will improve our understanding of the interactions between management, soil carbon and nitrogen and their contribution to productivity and nitrous oxide emissions. Management strategies that manipulate soil carbon to reduce nitrous oxide whilst delivering adequate nitrogen to meet crop demand following pasture will be assessed. Crop response to different nitrogen fertiliser management strategies (including inhibitors) and nitrous oxide emissions will be measured across a range of soils. This knowledge will facilitate the development of new Carbon Farming Initiative offset methodologies that help landholders simultaneously achieve greater nitrogen fertiliser use efficiencies and reduced nitrous oxide emissions in high rainfall environments.




Assessing opportunities for mitigating greenhouse gas emissions from irrigated broad-acre cropping systems in the southern Murray-Darling Basin—CSIRO—Wendy Quayle. Funding of $750 000 ex GST

This project will quantify year-round greenhouse gas, water and nutrient fluxes in irrigated, broad-acre cropping systems of the southern Murray Darling Basin. Current and emerging irrigation, fertiliser and stubble management practices with and without chemical inhibitors to mitigate greenhouse gas emission from these rotations will be investigated. Fluxes will be monitored using automated chambers over crops in weighing lysimeters and manual chambers and eddy covariance methods at field sites. The datasets will be used to calibrate and validate models. The result will be a framework for predicting greenhouse gas emissions in irrigated broad-acre cultivation for use in mitigation strategy development and inventory accounting.

Improved carbon and greenhouse gas outcomes through better understanding and management of soils and plant inputs at the farm scale—

The University of Sydney—Mark Adams. Funding of $700 000 ex GST

This project will develop methodologies for auditable quantification of carbon-equivalent benefits of management practices. Practices will include tillage and incorporation of legumes in crop rotations and pastures, with emphasis on the effects of management on soil structure and chemistry of soil organic matter. Methodologies include farm- or paddock-scale (flux) measures of carbon dioxide, methane and nitrous oxide as well as soil carbon sequestration. Outcomes of this phase of research will be incorporated into newly developed models that include temperature and moisture regimes determined using remote sensing. Final outcomes will be predictive tools that can be applied to the major cropping and grazing regions of New South Wales.

Advanced process level understanding of factors controlling gaseous nitrogen partitioning to reduce nitrous oxide losses from Australian agricultural soils—

Queensland University of Technology—Clemens Scheer. Funding of $498 761 ex GST

This project will improve the level of understanding of the interaction of the carbon and nitrogen cycles on nitrous oxide emissions, specifically the variation in the nitrous oxide to nitrogen ratio during emissions events. The partitioning between nitrous oxide and nitrogen gas emissions is influenced by soil moisture, carbon and nitrogen availability, and is a major area of uncertainty when predicting nitrous oxide emissions in response to management. Models are absolutely critical for the development and verification of practical abatement strategies to reduce nitrous oxide emissions under the Carbon Farming Initiative.

Characterising nitrous oxide emissions from nitrification—CSIRO—Ryan

Farquharson. Funding of $144 398 ex GST

This project will improve understanding and modelling of nitrous oxide emissions from nitrification by measuring potential nitrification rates and nitrous oxide emissions in




laboratory incubations of a range of soils from various production systems. The assumption that a constant proportion of nitrified nitrogen is emitted as nitrous oxide will be tested and updated model algorithms will be provided. This will allow improvement of models that in future may underpin the development and assessment of mitigation strategies.

Development of a low-emission nitrogen fertiliser based on slow release of ammonium from clay-modified activated charcoal—The University of

Newcastle—Scott Donne. Funding of $300 000 ex GST

This is a one year proof of concept project to further develop a novel nitrogen fertiliser that limits availability of substrate for denitrification. High emission agro-climatic regions are typified by high soil carbon and nitrogen input in high rainfall or irrigated zones (e.g. dairy, sugarcane, subtropical horticulture). By reducing the rate of nitrogen release to plants, via controlled desorption of ammonium from clay-modified activated carbon, the substrate for denitrification can be limited without reducing crop productivity. The fertiliser will be tested in controlled and field conditions, and data made available for Carbon Farming Initiative methodology development.

National Agricultural Greenhouse Gas Modelling Program

Potential soil carbon sequestration in Australian grain regions and its impact on soil productivity and greenhouse gas emissions—CSIRO—Enli Wang. Funding

of $639 283 ex GST

This project will define soil organic carbon (SOC) sequestration potential and identify management practices that benefit both productivity and SOC stocks. It will use the farming systems model APSIM (Agricultural Production Systems Simulator), together with measurements to identify agricultural practices that increase SOC, quantify SOC sequestration potential across Australian grain regions, assess the vulnerability of sequestered carbon to subsequent changes in management and climate, and investigate the impacts of SOC change on carbon-nitrogen cycling, productivity and greenhouse gas emissions.

Facilitation of improvement in systems modelling capacity for Carbon Farming Futures—CSIRO—Andrew Moore. Funding of $629 816 ex GST

This project aims to eliminate any inconsistencies in modelling activities across Filling the Research Gap (FtRG). It will ensure that models are developed and applied consistently in FtRG, and that they embody the best scientific understanding of methane, nitrous oxide and soil carbon fluxes. A series of workshops and comparative studies will result in more robust and consistent abatement predictions and increased human capacity for modelling.




Whole farm systems analysis of greenhouse gas abatement options for the southern Australian grazing industries—The University of Melbourne—Richard

Eckard. Funding of $537 902 ex GST

This project will conduct whole farm systems analysis of a range of nitrogen, carbon and energy efficiency and greenhouse gas abatement strategies for the dairy, sheep and southern beef industries. Each strategy will be analysed in a whole farm systems context, including methane, nitrous oxide, soil carbon, productivity plus the interactions between these. The outcomes from the project will be evaluated options: for reducing emissions intensity, improving farm profitability and/or further development into Carbon Farming Initiative offset methods.

The ‘Biosphere’ Graphic Element The biosphere is relevant to the work we do and aligns with our mission—we work to sustain the way of life and prosperity for all Australians. We use this shape as a recognisable symbol across our collateral.

For more information please contact:

Research and Adaptation Policy

Department of Agriculture, Fisheries and Forestry GPO Box 858 Canberra ACT 2601

Phone 1800 108 760

Email [email protected]

daff.gov.au/ccrp

http://www.daff.gov.au/climatechange/australias-farming-future/climate-change-and-productivity-research

research project summaries - agriculture · research project summaries overview the climate change...

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