Joint service unit : Ex & in situ experimental devices

Ecology is a young science. After a phase of census, observation and theorization, it is now necessary to move towards more experimental approaches that allow an integrated understanding of the processes that govern the impacts of global change and responses of biodiversity to these changes. The mission of the joint service unit “ex-in situ experimental de-vices” involves the setting-up and monitoring of experiments both in controlled conditions ex situ and in situ in natural environments for vegetation, terrestrial and marine animal models in order to clarify the dynamics and evolution of biodi-versity subjected to global changes such as e.g. global warming, modification of rainfall, pollution and biological invasions. It is also used as input for modelling these systems.

The joint service unit “Ex & in situ Experimental Devices” consists of four levels of experimental infrastructures.

Co-responsability
Laurence Affre & Thierry Gauquelin

Site Referents
Jardin, Serres, Phytotrons : Arne Saatkamp
CLIMED : Jean Philippe Mévy
O3HP : Mathieu Santonja
Aquariums : Carole Borchielini & Nicolas kaldonski

7 technical members
Lenka BROUSSET (TCN, AMU, 100%) – Arbois
Virgile CALVERT (TCE, AMU, 50%) - Station Marine d’Endoume
Sylvie DUPOUYET (AJT, AMU, 10%) – St Charles
Jean Philippe ORTS (AI, CNRS, 100%) – O3HP
Daniel PAVON (IGE, AMU, 100%) – Arbois
Hervé RAMONE (AI, Université Avignon) - Avignon
Marie-Dominique SALDUCCI (ASI, AMU, 10%) - St Charles

In natura

Infrastructures in natura

These infrastructures make it possible to manipulate ecosystems in order to simulate the reduction of precipitation pre-dicted by climate models in the Mediterranean.
• O3HP : The O3HP (Oak Observatory at OHP) experimental site is focussed on downy oak (Quercus pubescens) forests, one of the three flagship species and ecosystems of the French Mediterra-nean region and its functioning in the face of climate change. The system was set up, starting in 2009, at the Ob-servatoire de Haute Provence (OHP), and is organized around three elements : (i) a system of instrumented walk-ways, (ii) an original rain exclusion system covering approximately half of the plot (300 m2) and excluding around 35% of annual precipitation (iii) a network of sensors (temperature, moisture at different soil depth and in the can-opy as well as sap flow).
• CLIMED The CLIMED experimental site (2ha) located at the interface within the hills around Marseille offers an op-portunity to explore (i) the link between biodiversity and functioning of ecosystems, (ii) the susceptibility of species to climate change ; and (iii) the future of garrigue formations in the context of global change. This site encompasses a Mediterranean scrubland dominated by four shrubs species characteristic of garrigue vegetation, namely Quercus coccifera, Cistus albidus, Ulex parviflorus, Rosmarinus officinalis and Brachypodium retusum. This site is equipped with an automated weather station, temperature and humidity sensors and 93 rain exclusion devices installed in 2011 to test the influence of a decrease in precipitation which is 40% less rain under the devices on the structure and functioning of the garrigue ecosystem.

Experimental garden, greenhouses

Experimental garden, greenhouses and growth chambers

The experimental botanical garden at St Jerôme is equipped with an automated weather station and temperature and humidity sensors, several experimental surfaces and includes a collection of living plants, many of which are trees from Mediterranean basin. The three greenhouses at St Jerome are completed by two greenhouses at the Arbois and three at St Charles. This service unit includes 14 growht chambers which are used to control temperature, light and humidity con-ditions in order to study (i) the effect of environmental factors (water stress, temperature, pollution) on germination and growth, (ii) the importance of biotic interactions (competition, allelopathy, herbivory, pollination) on growth and repro-duction, (iii) the relationship between climatic factors of germination and in situ growth and in vitro developed models, and (iv) environmental variables relevant to the processes involved (air versus soil temperatures, precipitation versus soil water potential) as well as the relevenat spatio-temporal resolution for quantifying impacts on communities (monthly vs sub-hourly).

Aquariums

Aquariums

The marine station at Endoume (SME) is equipped with experimental natural sea-water aquariums allowing the breeding of several types of marine organisms. These aquariums also allow for experiments on thermo-tolerance, the impact of pollutants on organisms and their life cycle. The responses on living organisms are observed at different scales : morpho-logical, anatomical, genetic and epigenetic. Aquariums of artificial sea-water will allow to consider more controlled sys-tems (pH, temperature, photoperiod) for the separate analysis of the effect of the variation of different parameters. These aquariums are currently used for the breeding and manipulation of model organisms studied at the IMBE but will also allow us to attract researchers from other units wishing to work on living organisms. These ex situ approaches are com-plemented by in situ approaches carried out by the divers of the IMBE as part of the common diving service within the OSU Pythéas