Christina Birnbaum

PhD Candidate

Telephone: +61 (02) 9850 8160
Facsimile: +61 (02) 9850 8245

Email: christina.birnbaum[at]mq.edu.au

Building E8B 103

Department of Biological Sciences

Faculty of Science

Macquarie University

North Ryde, NSW, Australia, 2109

Background

I come from a small town in southern Estonia called Tartu. I spent six years there studying at the Estonian University of Life Sciences (www.emu.ee) where I completed my BSc (2005), MSc (incl. 5 months on a ERASMUS scholarship in Lublin Agrcicultural University, Poland) and started my Phd (2007). In October 2008 I relocated to Australia and started new doctoral studies with the PIREL group.

I have compiled an outdoor educational programme for elementary school classes and have twice co-organized a student camp called Summeracademy to promote sustainable lifestyles, organic food, maintainance of Estonian traditions, promoting co-operation and information exchange between farmers and students who study nature and agricultural sciences.

Acacia melanoxylon (Star swamp bushland, WA)

Lunchbreak in Augusta (WA)

Serpentine National Park, Western Australia

Tracking down roots of Acacia saligna (Esperance, WA)

Current Research

During next three to four years I will be focusing on effects of soil biota on invasive plant species. I am particularly interested in effects of soil biota on the growth of plant species in their new versus invaded range. We will be using Acacia sp. to test whether the soil biota has a positive or negative effect on a plant growth in its native compared to non-native range using standard feedback methods.
Some of the questions that I will be addressing with this study are:
- Are soil microorganisms predominantly responsible for the Acacias expansion into novel range?
- Could the establishment of Acacias in the novel range be attributed to mutualistic relations with soil microorganisms?
- Can microorganisms hinder the growth of Acacias in their native range but promote in the novel range?

Acacias have become weeds in some parts of Australia as well as in the world (Portugal, Israel, South Africa, United States and New Zealand). They form both N-fixing and mycorrhizal symbioses which help them grow successfully in nutrient-poor or disturbed (e.g. post-fire) soils. That is why they were widely used as dune stabilization plants in Mediterranean region (A. longifolia) and in South Africa (A. saligna). However, they have escaped the areas where they were originally planted and started to outcompete the native flora and modify the native soil systems. It is still widely unknown what the driving mechanism behind this success is. But we do know that some Acacias (e.g A. longifolia) can form easily N-fixing symbionts with wide range of root-nodule bacteria and this might be one of the many reasons for their success in novel areas. However recent studies from Portugal show that A. longifolia (Sydney golden wattle) was probably introduced as a seed or seedling with compatible rhizobia that facilitates A. longifolia growth and spread in the new range in Portugal compared to other native legumes. What is the role of rhizobia in Acacias invasion success within Australia is one of the many questions that I would like to address with my thesis. 

Previous Research

Over the last five years I have been investigating the distribution and growth dynamics of Solidago canadensis L. in Estonia. Since 2005 I have been compiling the Estonian alien invasive species dataset and factsheets for NOBANIS (North European and Baltic Network on Invasive Alien Species, www.nobanis.org) project. I have also represented Estonia in regular Nobanis international meetings. This experience has supported my increasing interest in invasion ecology.

Publications

Papers in prep:

 Birnbaum, C., Barrett, L.G., Thrall, P.H., Leishman, M.R. (2011) Mutualisms are not constrain cross-continental invasion success of acacias in Australia (submitted to Diversity and Distributions).

Birnbaum, C. et al. (2012) Diversity of nitrogen-fixing communities associating with invasive acacias in Australia (in prep).

Birnbaum, C. et al. (2012) Diversity of fungal communities associating with invasive acacias in Australia (in prep).

Book chapters:

Birnbaum, C. (2011). (Invited contribution). Book chapter on mink (Neovison vison): Zippy escapee from fur farms in ‘Environmental invaders - Invasive plants and animals in Europe’ (Haupt Verlag, Bern, Switzerland), pp. 173-180. 

Conference proceedings:

 Birnbaum, C., Leishman, MR. (2011). Cross-continental study on invasive Acacias in Australia: role of plant-soil feedbacks. In: Ecological Society of Australia 2011 Annual Conference Ecology in changing landscapes (book of abstracts). 21-25 November, Hobart, Australia. 

Birnbaum, C., Barrett, LG, Thrall, PH, Leishman, MR. (2011). Role of nitrogen fixing bacteria in the invasion success of Australian Acacias. In: EMAPi: 11th International Conference on the Ecology and Management of Alien Plant Invasions (book of abstracts). 30th August -3rd September, Szombathely, Hungary.

Birnbaum, C., Thrall, P. and M. Leishman (2010).  More is better? Rhizobial abundance and importance in invasion success of Acacias in Australia. In: Ecological Society of Australia 2010 Annual Conference Sustaining biodiversity – the next 50 years (book of abstracts). 4-10 December, Canberra, Australia. 

Birnbaum, C. (2008). Growth dynamics of Solidago canadensis L. In: Towards a synthesis: Neobiota book of abstracts: NEOBIOTA: 5th European Conference on Biological Invasions (book of abstracts), Prague (Czech Republic), 23-26. Sept. (Edit.). Pysek, P. & Pergl, J. Institute of Botany, Academy of Sciences of the Czech Republic, Průhonice, Czech Republic, 2008, 130.

Birnbaum, C. (2007). Distribution of the invasive Solidago canadensis L. in the vicinity of Tartu. In: Alien Species: Environment, Biorisks, Future: 5th Environment Symposium of the Maj and Tor Nessling Foundation (book of abstracts), 18-19 Jan 2007, Turku, Finland, 2007, 32.

Other:

Nobanis fact sheets, available on www.nobanis.org

Birnbaum, C. (2006). Invasive Alien Species Fact Sheet – Bunias orientalis.

Birnbaum, C. (2006). Invasive Alien Species Fact Sheet – Cercopagis pengoi.

Birnbaum, C. (2006). Invasive Alien Species Fact Sheet – Mustela vison.