POST-DOCTORAL POSITION OPEN in
ECOLOGY Maintenance of plant species diversity within forest metacommunities: patterns and processes associated to fragmentation among contrasted landscapes Open at the Jules Verne University of Picardy (UPJV) - Plant biodiversity Lab (FRANCE). Amiens city (North France, ca. 150 km north to Paris) - Prof. Guillaume DECOCQ Deadline for application: December 10th, 2009 Duration: 1 year, starting in January 2010. Requirements: The successful candidate is expected to have an experience in theoretical ecology, including mechanisms behind local species assemblages (a diversity), from niche-based to neutral models of species coexistence, as well as in metapopulation/metacommunity models. He/she is expected to have a publication record showing his/her skill to write high quality scientific papers, and capability to conduct statistical analysis with field data. The ability to use the R package and skills to conduct randomization tests is expected. The ability to conduct sophisticated statistical methods, such as multivariate models (e.g. Structural equation modelling), spatial statistics (e.g. PCNM) and Bayesian statistics will increase the candidates competitiveness. Background: Habitat fragmentation is recognized as one of the most important threat to biodiversity worldwide. This process has been extensively studied within the theoretical frameworks of Island biogeography and Metapopulation dynamics, both assuming that suitable habitat patches are isolated from one another by hostile habitats. The emergence of the metacommunity concept has provided a new framework to tackle unanswered questions relating to processes that pattern species assemblages at multiple spatial and temporal scales. In the special case of forest metacommunities, local plant diversity (i.e., at the patch scale) is affected by internal and external variables. Among internal variables patch area and patch age are well known to influence species richness through colonization/extinction processes, as predicted by the species-area relationship (SAR) and the species-time relationship (STR), respectively. External variables affecting forest plant species richness mostly relate to the surrounding landscape and its history, e.g. the spatio-temporal isolation of patches in a changing matrix. Fragmentation effects encompass the pure loss of habitat, the size reduction of the resulting remnant habitats, and the increasing spatial isolation of fragments, all three factors affecting population viability, dispersion, and long-term persistence of plant species. However, local extinction of species can occur with a substantial delay following habitat loss or degradation. Such extinction debts represent a challenge for biodiversity conservation across a wide range of taxa and ecosystems. Species with long generation times, such as many forest plant species, and populations near their extinction threshold are most likely to have an extinction debt. Although many studies support its existence, extinction debt is difficult to detect in natural communities. Also, quantifying an extinction debt remains challenging and accurate analytical methods are still to be developed. Moreover, the dynamic nature of metacommunities in both space and time has to be better taken into account to assess e.g. rescue effects that prevent local extinctions. Related to this topic is the question of the optimal size of a forest patch to ensure biodiversity conservation. Although recently rediscovered in the context of the study of nestedness of communities, the Single Large Or Several Small (SLOSS) controversy is an old idea which needs to be revisited within a macroecological framework, incorporating land use changes at multiple spatial and temporal scales. Mission: Confronting the results of empirical studies (already available) to predictions from various theoretical models; more specifically: - measuring the extinction debt across contrasted forest metacommunities by using different approaches (incl. testing how well the results from empirical studies fit the prediction of niche- based and neutral models of species assemblages); analyzing the importance of the landscape matrix and its history - revisiting the SLOSS controversy (Single Large or Several Small) within the framework of forest fragments; Research group: the position is offered at the Plant biodiversity Lab, within the research unit Dynamiques des Systèmes Anthropisés (JE 2532 DSA). Researches focus on plant biodiversity patterns and processes, especially in forest ecosystems that are under human influence. The post-doc will join a group working on the spatio-temporal dynamics of forest metacommunities and the relation between a, b and g diversity at multiple spatial and temporal scales. He will handle both empirical and simulation data, contribute to field work, and supervise some students. He will have a full autonomy in conducting his research activities. Salary: ca. 1800-2000 net per month Applications for the fellowship including a CV, a cover letter describing why the project interests you, and the names and e-mail addresses of referees are to be sent to: Prof. Guillaume DECOCQ ([email protected]) University of Picardy Jules Verne - Plant Biodiversity Lab, 1 rue des Louvels, F-80037 Amiens Cedex, France. Tel/Fax: +33 (0)322 827 761 (website currently unavailable)
