Yves Caraglio

Climate Change Impact on Tree Architectural Development and Leaf Area

The response of forests to the forecasted increase in climate stress occurrence is considered a key issue in climate change scenarios [1]. Although forest productivity increased in most ecosystems during the 20th century [2,3], a review by Allen et al. [4] underlined an emerging trend of heat and drought induced forest decline and dieback at global scale. Several and generally combined physical and biological causes contribute to observed tree decline or die-off [4-7]. Apart extensive insect outbreaks [8], understanding the respective role of hydraulic failure and carbon starvation due to excessive or long lasting water stress is one of the major research goal in order to predict forest response to climate change [9].

Simulation of morphogenetical gradients using a minimal functional-structural plant model (FSPM)

Context: Architectural studies highlight recurrent morphogenetical gradients that are observed on some tree species. These morphogenetical gradients are linked to morphological trends among successive shoots throughout plant structure and ontogeny. This study aims at testing a potential origin of these gradients as the complex result of some core plant functions. It will be achieved through a minimalist mathematical modelling approach.

Plant growth architecture and production dynamics : A set of e-learning resources

FSPM Plant and crop models are popular in the research community and there is increasing interest in their applications, from yield prediction to crop management optimization. A wide range of approaches and their software implementation can be found in the literature, with a large diversity in modelling scale (from plant organ to plot levels) and scope (structural, functional or both), as well as generic or specific aim. However, most of these approaches rely on similar key assumptions and methods related to different disciplines: botany for plant structure, eco-physiology for production, statistics and dynamic system theory for parameter identification and estimation. Web disseminated plant and crop models learning supports are not numerous, often specific, and partial. We present here a set of e-learning resources, named “Plant growth architecture and production dynamics” which describes the main notions from plant morphology and architecture, eco-physiology and applied mathematics necessary to the understanding of most plant and crop models, and their typology. In this paper, after an overview of existing learning resources on plant and crop modelling which, we believe, might be of interest for the whole research community, we present the proposed resource, which uses the GreenLab model as illustration, organized as follows: •Five standalone introductive disciplinary resources: botanical notions, assumptions in eco-physiology, basis in data processing, introduction to models, introduction to GreenLab •An FSPM example in more details: GreenLab positioning, its basis, structure modelling, production modelling, and applications including model fitting and a study case •Tools: inline (for structure analysis and statistics), online (access to fitters for instance) and access to download simulators and their documentation •Glossary, bibliography, web site collection, and a pedagogic kit for instructors Supported by the French Sustainable Development Virtual University (UVED), the e-learning resource http://greenlab.cirad. fr/GLUVED/ was labelled after evaluation, with its 5 independent introductive learning chapters and its major course. These self-learning pedagogic chapters, written in English, can be combined or not, and share similar organization. Pages are indexed by website indexing tools that allow following the site activity and rate of visits.