Research

My present research interests concern the chemical, physical and biological properties of soil with particular focus on soil hydrophobicity (or water repellency) and the factors which influence its measurement, expression, abatement, destruction and recurrence. This phenomenon influences the delayed onset of water infiltration into affected soils reducing storage capacity and promoting surface run-off and/or evaporation. Recently atomic force microscopy (AFM) has been used to examine the distribution of surface mechanical properties on soil mineral particle surfaces and this has been used to infer the distribution and strength of adhesion of adsorbed organic material on particle specimens drawn from both hydrophilic and hydrophobic soils. It is hoped to extend the range of investigations to examine the extent to which micro-organisms (and their by-products) within soils influence hydrophobicity.
 
The heating of surface soils as a result of wild fire, or the use of fire as a land management tool, has a variety of interesting effects on soil chemistry leading to a redistribution of hydrophobicity (and changes in its persistence) within the soil column and a potential wide variety of outcomes dependent on subsequent meteorological conditions. A detailed examination of the carbon balance associated with wildfire is also in progress.

Selected publications

• Robert Bryant, Changes in organic compound composition in soil following heating to maximum soil water repellency under anoxic conditions, Environmental Chemistry, 2012, 9, 4, [DOI: 10.1071/en11122]
• Robert Bryant, Reaction of soil water repellency to artificially induced changes in soil pH, Geoderma, 2010, [DOI: 10.1016/j.geoderma.2010.06.005]
• Robert Bryant, Raindrop Impact: A Neglected but Potentially Major Contributor to Particle Mobilization in Soils, Soil Science Society of America Journal, 2010, [DOI: 10.2136/sssaj2009.0245]
• Robert Bryant, Investigation of Surface Properties of Soil Particles and Model Materials with Contrasting Hydrophobicity Using Atomic Force Microscopy, Environmental Science & Technology, 2009, [DOI: 10.1021/es900158y]
• R. Bryant, S. H. Doerr, G. Hunt, S. Conan, Effects of soil compaction on soil surface water repellency Soil Use and Management, 2007, pp.238-244, [ISBN:1475-2743], [DOI: 10.1111/j.1475-2743.2007.00088.x]
• Robert Bryant, Effects of heating and post-heating equilibration times on soil water repellency, 2005, pp.261:267, [ISBN:0004-9573], [DOI: 10.1071/SR04092 0004-9573/05/030261]
• Robert Bryant, The effect of oxygen deprivation on soil hydrophobicity during heating, 0, pp.457:474, [ISBN:1049-8001], [DOI: 10.1071/WF05035 1049-8001/05/040449]
• Robert Bryant, Engineering Output - DOI Lookup fails, 0, [DOI: 10.1021/es02319a]

Teaching

• EG-100 - Chemical Process Principles (12/13)

Research theses supervised

PhD

• 2010 - Long-term carbon capture by biochar in European soils (2nd Supervisor: Professor Frances Street-Perrott)
• 2009 - Strategies for enhanced valorisation of organic wastes (2nd Supervisor: Dr. Robert Lovitt)
• 2006 - Soil water repellency: comparison between individual particles and bulk properties (2nd Supervisor: Dr. Christopher Wright)

MRes

• 2005 - Evaluation of Laser Scanning Confocal Microscopy in the Investigation of Soils. (2nd Supervisor: Professor Stephen Wilks)

MSc

• 2008 - Investigation of the Thermal Characteristics of an Anila Biomass Gassifier Stove
• 2008 - Characteristics of biochar by experimental methods