Job opportunities

Post-doctoral fellowship at INRA, Bordeaux (France)

APPLICATION CLOSED

A global assessment of tree diversity effects on leaf insect herbivory: from patterns to mechanisms

Keywords: Associational effects, Biodiversity, Forest, Herbivory, TreeDivNet

We are looking for a post-doc fellow with interest in plant-insect interactions for a 12 months contract in Bordeaux from January to December 2018.

– Deadline for application, September 30 –

The area of planted forests is expanding worldwide, but 99% of them are tree monocultures. Yet, tree diversity is increasingly acknowledged to support several ecosystem functions and deliver associated ecosystem services (ES, Gamfeldt et al. 2013, van der Plas et al. 2016). One main ES is the regulation of damage caused by insect herbivores (Guyot et al. 2016). Trees are generally more resistant to insect herbivores in mixed forests than in monocultures (Castagneyrol et al. 2014), but there are examples showing the opposite (Schuldt et al. 2015).

Climate is a poorly studied factor likely responsible for discrepancies among existing studies on diversity-resistance relationships (Kambach et al. 2016). Several studies reported that the strength of biotic interactions (Moles et al. 2011, Rodríguez-Castañeda 2013) in general and plant-insect interactions (Kozlov et al. 2015b, Moreira et al. 2015, Abdala-Roberts et al. 2016) in particular change along large scale climatic gradients. Resulting effects of climate on herbivory may be due to the direct effects of climate – being precipitations or temperatures – on herbivores or indirect effects through plant anti-herbivore defences (Zvereva and Kozlov 2006, Jactel et al. 2012). As such, climate may influence the strength and direction of tree diversity effects on herbivory. In the current context of climate change, there is thus an urgent need to better understand how climate may drive tree diversity effects on tree-herbivore interactions.

In 2017, birch leaves (Betula pendula) were collected in eight sites of the tree diversity network (TreeDivNet, Verheyen et al. 2016) where tree diversity was experimentally manipulated. Sites are distributed across Europe and North America along a 17° latitudinal gradient covering most of the climatic gradients naturally experienced by Betula pendula (Atkinson 1992). This unprecedented coverage will allow testing the interactive effects of climate and tree diversity on both insect herbivory and anti-herbivore defences in birch leaves. In addition in 3 sites (ORPHEE, FORBIO, IDENT Cloquet) water supply has been manipulated, which enables experimentally testing the interactive effect of one climatic factor (precipitation) and tree diversity on insect herbivory.

We will take care of estimating herbivory on birch leaves before the contract starts so that the post-doc fellow (PDF) will be offered a dataset ready to be analysed. Analyses of foliar chemical traits will be initiated in autumn as well but may last a few weeks after the contract starts. During the first 6 months, most of PDF’s work will thus consist in analyzing the data and writing a scientific paper.

This work is embedded within a larger project aiming to study interactive effects of tree diversity and climatic factors on below- and above-ground processes to which the PDF will be associated. Co-workers in the research group at INRA BIOGECO manage the ORPHEE experiment which is part of TreeDivNet. They have strong expertise in tree-insect interactions. They are currently leading related projects on tree-tree-insect interactions to which the PDF could be associated.

We are looking for PDF familiar with the biodiversity and ecosystem functioning framework with interest and experience in plant-insect interactions. Excellent skills in statistical analyses will be appreciated.

Applicants should send a detailed CV (2 pages max.) and up to two support letters, not later than 30 September 2017. Documents will be sent by e-mail* to Bastien Castagneyrol (see below). All documents must be sent as pdf files, and be formatted as NAME_Surname_XXX.pdf, where XXX is CV, supportletter1 or supportletter2.

We will short list applicants and offer them skype interview around mid-October 2017.

Further inquiries, please contact Bastien Castagneyrol (bastien.castagneyrol@inra.fr) and/or Hervé Jactel (herve.jacetl@inra.fr).

Merci !!

* There is no need to attach a motivation letter, but please make sure that you explain why you apply and why you are qualified in your e-mail.

References

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