Justine Edwards - PhD Student

School of Plant Biology (M090)
University of Western Australia
Crawley WA 6009
AUSTRALIA

telephone     +61 8 6488-7923
fax               +61 8 6488-7925
email           jgedward@cyllene.uwa.edu.au

B Sc (Env. Sci) (Hons), Murdoch University, 1993

Research interests

•root architecture
•fine root distribution and turn over,
•plasticity of root growth and development in response to environmental variables

PhD Thesis :  Root development and plasticity in Eucalyptus, Casuarina and Pinus species

Supervisors: Prof Mark Adams (UNSW), Dr Tina Bell (DSE, Victoria) , Dr Pauline Grierson (UWA) and Dr John McGrath (Forest Products Commission, WA).
Funding: ARC Linkage grant with Dept. of Environment and Conservation, UWA small grant with Dr Pauline Grierson

Project summary 

This research is quantifying the plasticity of root architecture of a range of tree species in response to environmental variables. 

(i) Root architecture of juveniles grown in contrasting media (sand and vermiculite) were examined for differences in root architecture and plasticity. Root systems have been harvested intact and root architecture quantified by scanning the complete root system and measuring topological and geometrical values using BranChing software (Plant and Soil (1992) 140: 145-149).

(ii) I have quantified the structural root architecture of mature trees grown in contrasting field environments - a dry, nutrient poor site and a moist nutrient rich site.  Mature trees were excavated by hand and roots greater than 2mm mapped in 3D using a Polhemus FASTRACK electromagentic digitiser with a long range transmitter. Patterns of the structural roots have been analysed using AMAPmod software to investigate species differences, site differences and species site interactions.

(iii) I have measured fine root biomass and turnover of the same tree species at both sites above using contrasting methods. Fine root biomass and turnover has been measured using sequential coring soil coring in conjunction with a ¹⁵N tracer technique (Oecologia 1997 112: 300-304) and a compartment respiration model (Soil Biology & Biochemistry 1998 30: 961-968).  Species differences, interactions with environmental variables and a comparison of the three different techniques have been investigated.

This research is now being finalised for publication.
 
 

Publications and conference abstracts

Recent conference presentations

2003
Edwards J  Field-based 3D digitising of woody root architecture – techniques and results. Proceedings Third International Symposium Dynamics of Physiological Processes of Woody Roots.  Perth, Australia Sep 29-Oct 3, p 36.

Edwards JG, Adams MA, Bell TL and Grierson PF   Fine root production and turn over in Pinus  and Eucalyptus species – an evaluation of methods. Proceedings Third International Symposium Dynamics of Physiological Processes of Woody Roots.  Perth, Australia Sep 29-Oct 3, p 123.

Graham J, Edwards, JG, Livesley SJ, Landman PA, and Grierson PF Root anatomy and architecture in relation to water use by Melaleuca argentea W. Fitz. Proceedings Third International Symposium Dynamics of Physiological Processes of Woody Roots.  Perth, Australia Sep 29-Oct 3, p 128.

2001
Plasticity of root growth and architecture in Eucalyptus and Pinus species. 6th ISRR Symposium. Roots: the Dynamic Interface Between Plants and the Earth. Nagoya, Japan, 2001

1999
Plasticity of root architecture in juvenile tree species. Ecological Society of America Annual Meeting, Spokane, Washington, USA, 1999.

Architectural plasticity of juvenile tree roots. (Poster). Second International Symposium - Dynamics of Physiological Processes in Woody Roots. Nancy, France, 1999.

Other publications of interest

Utility of simple site classifications for predicting Eucalyptus globulus productivity. Australian and New Zealand Soils Conference, Melbourne, Australia, 1996.

Site evaluation for Eucalyptus globulus in south-western Australia for improved productivity and water uptake. 4th National Conference and Workshop on the Productive Use and Rehabilitation of Saline Lands, Albany, Australia, 1996.

Principles of site evaluation and selection for integrating tree species into the farming environment.  Agriculture Dept., University of Western Australia, Perth, Australia, 1997.

Site evaluation and selection for tree species in the wool belt of Western Australia. Master TreeGrowers Course, Kojonup, Australia, 1999.

Useful Links

Plant Architecture Information Systems (PAIS)
Below Ground Research at York