This platform is composed of 16 independent experimental semi-closed units each hosting intact or reassembled ecosystems of to 1 tons (area 1 m², depth up to 1 m). This platform under natural light conditions both controls the environment of the ecosystems (T°C, HR, CO2, 13C CO2) and measures on line ecosystem and soil gas exchanges (CO2, H2O, CH3, N2O) and isotopes fractionation (C and O in CO2, N in N2O) in addition to environmental conditions.

Microcosms are small containers dedicated to aquatic microbial ecosystems studies from single populations to communities of bacteria, microalgae and other planktonic organisms. Currently, we have in our dedicated laboratories 13 chemostats (single glass vessels) for culturing bacteria and phytoplankton in sterile conditions and 4 double-system chemostats (paired system made out of two connected glass vessels) dedicated to the study of phyto- and zooplankton interactions and dynamics. All the systems can be used to run continuous cultures in a light and temperature controlled environment. Several facilities are also available to support the user’s work (laminar hood, flow-cytometer, autoclave, microscopes, oxygen and nutrients analyzers, see the analytical instrumentation section for more details). Moreover, we have 36 custom-made open-top aquatic microcosms dedicated to experimentation on aquatic ecosystems in the Ecolab environmental chambers. As much as 12 aquatic microcosms, made out of stainless steel, can be deployed in each climate chamber of the Ecolab system. Temperature, water mixing and irradiance can be precisely controlled inside each microcosm, and atmospheric conditions are precisely regulated. A flow-through respirometric system dedicated to accurate measurement of O2 and CO2 exchanges with the air and stable isotope (C12/C13 ratio of CO2 in the atmosphere) is under development, in order to perform measurements on ecosystems mass-balance.

Web interfaces have been developed to facilitate running experiments with research teams not permanently on site. They allow submitting proposals and defining precisely experimental set-ups; they also act as electronic lab-books and allow to view and retrieve data. Data are available on quasi real time (delay of a couple hours).

The Microcosms platform houses 13 identical and independent growth chambers. These growth chambers allow to experiment on a variety of ecological systems, from populations to small soil microcosms as well as with small ecosystems driven by photosynthetic organisms. These custom-made growth chambers have a volume of 2 m3 and a working area of 1 m2. They possess a unique external zenithal light compartment allowing the use of various types of lamps, such as plasma lamps or LED panels providing a light spectrum close to the sunlight one. These 13 chambers allow to condition the environment for temperature, relative humidity (including very low level through to dry air injection), CO2 (including pre-industrial level through injection of CO2 free air) and 13C for organic matter labelling. Gas exchange measurements (CO2, H2O, N2O and CH4 fluxes ) and isotopic fractionation (13C and 18O in CO2; 15N in N2O; 18O, 17O and 2H in H2O) can be done on separate microcosms conditioned in each chamber and connected to specific analysers (LiCor 6400, Picarro or Aerodyne laser analysers).

Each Ecolab includes a laboratory room and three identical closed environmental chambers, each of a volume around 13 m3, conditioned by independent technical bodies controlled from a centralized supervisor. At present, the Ecolab enables precise real-time programming of weather conditions (temperature, humidity, and precipitation), of the concentrations of some atmospheric gases (CO2 and O2, as well as O3 in three chambers) and of several artificial lighting conditions. It can produce climate conditions varying from cold polar environments to hot and humid tropical environment. It can regulate weather conditions accurately to simulate slow or sudden changes, and can independently change climate conditions from gas concentrations in the atmosphere. Each environmental chamber is equipped with a mesocosm to confine terrestrial or aquatic ecosystems. This mesocosm consists of a stainless steel tank with a double jacket and enables real-time control of thermal gradients in the ecosystem independently from the atmosphere. Artificial light can be provided by incandescent bulbs, plasma lamps or modular LED source depending on the research project. Rainfall is provided by sprinklers and the quantity and quality of rainfall can be controlled

This platform is composed of 12 independent experimental semi-closed units each hosting intact or reassembled ecosystems of to 10 tons (area 2, 4 or 5 m², depth up to 2 m). This platform under natural light conditions both controls the environment of the ecosystems (T°C, HR, CO2, 13C CO2) and measures on line ecosystem and soil gas exchanges (CO2, H2O, CH3, N2O) and isotopes fractionation (C and O in CO2, N in N2O) in addition to environmental conditions.

At the Ecotron IleDeFrance, an analytical platform is dedicated to water microbiology and biogeochemistry. At the Montpellier Ecotron, a portable gas sampling and analysis system is available as well as isotopes laser analysers.

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The Ecotrons services described above host various equipment to control the environment (e.g. air conditioning systems, gas analysers, light spectrometers, soil humidity sensors, soil matric potential regulator) as well as instruments to mesure ecosystem processes (e.g. gas and isotopes analysers, strain gauges). The analytical platforms hold flow cytometer, compact titration station, double beam spectrophotometer, continuous segmented flow analyser, ecoplate (IleDeFrance) and water isotope analyser in liquid and gaseous form, automated chamber for gas sampling and analysis (CO2, N2O, CH4) (Montpellier).