Physical Sciences and Mathematics Commons^™

Farm Gate Nutrient Balances In South West Western Australia – An Overview, Rebecca Ovens, David Weaver, Nardia Keipert, Simon Neville, Robert Summers, Martin Clarke

Conference papers and presentations

Farm-gate nutrient budgets can be used to identify the efficiency of nutrient use within and between individual enterprises and catchments, and may be used to represent a component of the risk that particular landuses represent to water quality. Over the past 5 years, more than 400 farm-gate nutrient balance audits have been conducted across a range of catchments and landuses in southwest Western Australia (WA). Values for nutrient use efficiency and surpluses across landuses and catchments are reported. Patterns of nitrogen and phosphorus signatures closely reflect one another across landuses, though nitrogen input, output and surplus values are consistently higher …

Land Use Influences The Spatiotemporal Controls On Nitrification And Denitrification In Headwater Streams, Clay P. Arango, J. L. Tank

All Faculty Scholarship for the College of the Sciences

N and C cycles in headwater streams are coupled, and land use can modify these cycles by increasing N availability and removing riparian vegetation. To increase our understanding of how land use modifies the controls on N cycling, we quantified rates of 2 microbial N transformations in a total of 18 agricultural and urban streams (with and without riparian buffers) for 3 y to examine how riparian vegetation and land use influence sediment nitrification and denitrification. Nitrification rates were highest in agricultural streams in late spring. Nitrification was not related to streamwater NH₄⁺ concentrations but was positively related …

Crop Updates 2008 - Farming Systems, John De Majnik, Paul Meibusch, Vince Logan, Louise Barton, Wahid Biswas, Daniel Carter, Nicolyn Short, Jodie Bowling, Glen Riethmuller, James Fisher, Moin Salam, Stephen Davies, Jim Dixon, Dennis Van Gool, Alison Slade, Bob Gilkes, Megan Abrahams, Caroline Peek, Daniel Gardiner, Kari-Lee Falconer, David Hall, Jeromy Lemon, Harvey Jones, Yvette Oliver, Tania Butler, Michael Robertson, Stephen Carr, Chris Gazey, David York, Joel Andrews, Michael Simeoni, G. Peter Mangano, Svetlana Micic, Dave Gartner, Adam Clune, Matthew Morell, Adam Umbers, Angelo Loi, Brad Nutt, Clinton Revell, Geoff Kew, Vivien Vanstone, Ali Bhatti, Ming Pei You, Imma Farre, Bill Bowden, Henry Smolinski, Jane Speijers, John Bruce, David Mccarthy, Gary Lang, David Rees, Rob Grima, John Young, Ross Kingwell, Chris Oldham, Derk Bakker, Ian Foster, David Beard, Wen Chen, Richard Bell, Ross Brennan, Art Diggle, Reg Lunt, Qifu Ma, Zed Rengel, Tim Hilder, Dusty Severtson, Shahajahan Miyan, Sam Clune, Barb Sage, Tenielle Martin, Chris Newman, Neal Dalgliesh, Caroline Peak, Andrew Blake, Megan Ryan, Richard Bennett, Tim Colmer, Daniel Real, Jiyan Pang, Lori Kroiss, Dion Nicol, Tammy Edmonds-Tibbett, Ron Mctaggart, Sean Kelly, Helen Hunter

Crop Updates

This session covers thirty nine papers from different authors:

PLENARY

1. Developments in grain end use, Dr John de Majnik, New Grain Products, GRDC, Mr Paul Meibusch, New Farm Products and Services, GRDC, Mr Vince Logan, New Products Executive Manager, GRDC

PRESENTATIONS

2. Global warming potential of wheat production in Western Australia: A life cycle assessment, Louise Barton1, Wahid Biswas2 and Daniel Carter3, 1School of Earth & Geographical Sciences, The University of Western Australia, 2Centre of Excellence in Cleaner Production, Division of Science and Engineering, Curtin University of Technology, 3Department of Agriculture and …

Crop Updates 2008 - Cereals, Christine Zaicou, Shahajahan Miyan, Brenda Shackley, Steve Penny, Sarah Ellis, Darshan Sharma, Blakely Paynter, Jeff Russell, Andrea Hills, Glen Riethmuller, Bill Bowden, Paul Blackwell, Harmohinder Dhammu, Vince Lambert, Chris Roberts, David Cox, Sally Cox, Jeremy Lemon, Paul Damon, Zed Rengel, Geoff Thomas, Ciara Beard, Anne Smith, Kith Jayasena, Sean Kelly, Rob Loughman, Bill Macleod, Raj Malik, Ravjit Khangura, Vivien Vanstone, Colin Hanbury, Mehreteab Aberra, Gordon Masnish, Brenda Coutts, Geoff Strickland, Monica Kehoe, Dustin Severtson, Roger Jones, Dominie Wright, Megan Jordan, Xinhua He, Eli Manyol, Song-Ai Nio, Imran Malik, Tina Botwright-Acuña, Len Wade, Nigel Metz, Linda Price, Dean Diepeveen, Leisa Armstrong, Peter Clarke, Doug Abrecht, Rudi Appels, Matthew Bellgard

Crop Updates

This session covers twenty four papers from different authors:

WHEAT AGRONOMY

1. Wheat variety performance in the Northern Agricultural Region in 2007, Christine Zaicou, Department of Agriculture and Food

2. Wheat variety performance on the Central Agricultural Region in 2007, Shahajahan Miyan, Department of Agriculture and Food

3. Response of wheat varieties to sowing time in the Great Southern and Lakes Region in 2007, Brenda Shackley and Steve Penny, Department of Agriculture and Food

4. Wheat variety performance in the South Coastal Region in 2007, Sarah Ellis, Department of Agriculture and Food

5. Flowering dates of wheat varieties in Western …

Interactions Between Changing Pco2, N2 Fixation, And Fe Limitation In The Marine Unicellular Cyanobacterium Crocosphaera, Fei-Xue Fu, Margaret R. Mulholland, Nathan S. Garcia, Aaron Beck, Mark E. Warner, Sergio A. Sañudo, David A. Hutchins

OES Faculty Publications

We examined the physiological responses of steady-state iron (Fe)-replete and Fe-limited cultures of the biogeochemically critical marine unicellular diazotrophic cyanobacterium Crocosphaera at glacial (19 Pa; 190 ppm), current (39 Pa; 380 ppm), and projected year 2100 (76 Pa; 750 ppm) CO₂ levels. Rates of N₂ and CO₂ fixation and growth increased in step with increasing partial pressure of CO₂ (pCO₂), but only under Fe- replete conditions. N₂) and carbon fixation rates at 75 Pa CO₂ were 1.4-1.8-fold and 1.2-2.0-fold higher, respectively, relative to those at present day and glacial pCO_{2 …}