Physical Sciences and Mathematics Commons^™

Microbial Nitrogen Limitation Increases Decomposition, Joseph M. Craine, Carl Morrow, Noah Fierer

Dartmouth Scholarship

With anthropogenic nutrient inputs to ecosystems increasing globally, there are long-standing, fundamental questions about the role of nutrients in the decomposition of organic matter. We tested the effects of exogenous nitrogen and phosphorus inputs on litter decomposition across a broad suite of litter and soil types. In one experiment, C mineralization was compared across a wide array of plants individually added to a single soil, while in the second, C mineralization from a single substrate was compared across 50 soils. Counter to basic stoichiometric decomposition theory, low N availability can increase litter decomposition as microbes use labile substrates to acquire …

Sheep Updates 2007 - Part 3, Andrew Ritchie, Edward Riggall, James Hall, Gus Rose, Johan Greeff, John Young, M. Alchin, M. Young, T. Johnson, John Lucy, Martin Staines, Tim Wiley, Rob Grima, Sandra Prosser, Matt Ryan, Geoff Moore, Tony Albertsen, Phil Barrett-Lennard, George Woolston, John Titerington, Sarah Knight, Brianna Peake

Sheep Updates

This session covers seven papers from different authors:

PROFITABILITY

1. Benchmarking demonstrates both the potential and realised productivity gains in the sheep and wool industry, Andrew Ritchie, Edward Riggall and James Hall, ICON Agriculture, Darkan

2. Improving sheep genetics will increase farm profitability, Gus Rose, Johan Greeff Department of Agriculture and Food Western Australia, John Young Farming Systems Analysis Service, WA

3. Meat, Merinos and making money in WA Pastoral Zone, M. Alchin, M. Young and T. Johnson, Department of Agriculture and Food Western Australia,

GRAZING

4. Nitrogen - farmers' friend or foe? John Lucy and Martin Staines, Department …

Crop Updates 2007 - Farming Systems, David Jeffries, A. Loi, B. J. Nutt, C. K. Revell, Yvette Oliver, Michael Robertson, Bill Bowden, Kit Leake, Ashley Bonser, Ian Maling, Bindi Isbister, Garren Knell, Alison Slade, David Stephens, Michael Meuleners, David Beard, Nicolyn Short, Rob Grima, Ingrid Richardson, Ruhi Ferdowsian, Geoff Bee, David Evans, Bob Gilkes, Senthold Asseng, Jim Dixon, Felicity Byrne, Mike Ewing, Dennis Van Gool, Louise Barton, Ralf Kiese, David Gatter, Klaus Butterbach-Bahl, Renee Buck, Christoph Hinz, Daniel Murphy, Cameron Weeks, Meredith Fairbanks, John Peirce, Brad Rayner, Sandy White, Paul Damon, Qifa Ma, Zed Rengel, Ed Barrett-Lennard, Meir Altman, Tracey M. Gianatti, Lindsay Bell, Ben Webb, Caroline Peek, Paul Sanford, Paul Blackwell, Glen Riethmuller, Darshan Sharma, Mike Collins, Frank D'Emden, David Hall, G. P. Manango, D. L. Steverson, Vanessa Stewart, Julie Roche, Peter Rutherford, Imma Farré, Ian Foster, Stephen Charles, Frances Hoyle, N. Milton, M. Osman, L. K. Abbott, W. R. Cookson, S. Darmawanto, Rob Sands, David Mccarthy, Paul Carmody, J. Russell, J. Eyres, G. Fosbery, A. Roe, Phil Nichols, Andrew Bathgate, Anne Wilkins

Crop Updates

This session covers forty papers from different authors:

1. Quality Assurance and industry stewardship, David Jeffries, Better Farm IQ Manager, Cooperative Bulk Handling

2. Sothis: Trifolium dasyurum (Eastern Star clover), A. Loi, B.J. Nutt and C.K. Revell, Department of Agriculture and Food

3. Poor performing patches of the paddock – to ameliorate or live with low yield? Yvette Oliver¹, Michael Robertson¹, Bill Bowden², Kit Leake³and Ashley Bonser³, CSIRO Sustainable Ecosystems¹, Department of Food and Agriculture², Kellerberrin Farmer³

4. What evidence is there that …

Species Richness And Soil Properties In Pinus Ponderosa Forests: A Structural Equation Modeling Analysis, Daniel C. Laughlin, Scott R. Abella, W. Wallace Covington, James B. Grace

Public Policy and Leadership Faculty Publications

Question: How are the effects of mineral soil properties on understory plant species richness propagated through a network of processes involving the forest overstory, soil organic matter, soil nitrogen, and understory plant abundance? Location: North-central Arizona, USA. Methods: We sampled 75 0.05-ha plots across a broad soil gradient in a Pinus ponderosa (ponderosa pine) forest ecosystem. We evaluated multivariate models of plant species richness using structural equation modeling. Results: Richness was highest at intermediate levels of understory plant cover, suggesting that both colonization success and competitive exclusion can limit richness in this system. We did not detect a reciprocal positive …

Impact Of More Intensive Grazing On Nitrogen And Phosphorus In Shallow Aquifers Of The Southern Perth Basin, D L. Bennett, Patrick Donnelly, Peter J. Tille

Resource management technical reports

This study reports on the nutrient content, pH and salinity of groundwater samples collected from the watertable and within the Superficial and the upper Leederville Aquifers from the Southern Perth Basin, south of Pinjarra, Western Australia. Sampling was undertaken to determine the impact of intensification of broadscale grazing on groundwater nutrients in the area.